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authorRoger Frank <rfrank@pglaf.org>2025-10-14 20:08:31 -0700
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+The Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever. You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Arteriosclerosis and Hypertension:
+ with Chapters on Blood Pressure, 3rd Edition.
+
+Author: Louis Marshall Warfield
+
+Release Date: October 12, 2011 [EBook #37675]
+
+Language: English
+
+Character set encoding: ISO-8859-1
+
+*** START OF THIS PROJECT GUTENBERG EBOOK ARTERIOSCLEROSIS AND HYPERTENSION: ***
+
+
+
+
+Produced by Bryan Ness, Julia Neufeld and the Online
+Distributed Proofreading Team at http://www.pgdp.net (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+
+Transcriber's Notes: Passages in italics are indicated by _underscores_.
+
+Passages in bold are surrounded by =.
+
+Small caps have been replaced by ALL CAPS.
+
+
+
+
+ERRATUM
+
+
+Page 75, Figure shown is not the Brown sphygmomanometer described in the
+text, but the Baumanometer manufactured by W. A. Baum Co., Inc., New
+York. It is claimed that the Baumanometer is made with particular care
+and hence the readings are said to be more accurate than other mercury
+instruments. It is apparently a good instrument. The author has had no
+personal experience with it.
+
+
+
+
+ ARTERIOSCLEROSIS
+
+ AND
+
+ HYPERTENSION
+
+ With Chapters on Blood Pressure
+
+ BY
+
+ LOUIS M. WARFIELD, A.B., M.D., (Johns Hopkins),
+ F.A.C.P.
+
+ FORMERLY PROFESSOR OF CLINICAL MEDICINE, MARQUETTE UNIVERSITY MEDICAL
+ SCHOOL; CHIEF PHYSICIAN TO MILWAUKEE COUNTY HOSPITAL; ASSOCIATE
+ MEMBER ASSOCIATION AMERICAN PHYSICIANS; MEMBER AMERICAN
+ ASSOCIATION PATHOLOGISTS AND BACTERIOLOGISTS;
+ AMERICAN MEDICAL ASSOCIATION, ETC., FELLOW
+ AMERICAN COLLEGE OF PHYSICIANS
+
+ _THIRD EDITION_
+
+ ST. LOUIS
+
+ C. V. MOSBY COMPANY
+
+ 1920
+
+ COPYRIGHT, 1912, 1920, BY C. V. MOSBY COMPANY
+
+
+ _Press of
+ C. V. Mosby Company
+ St. Louis_
+
+
+ TO
+
+ MY MOTHER
+
+ THIS VOLUME IS AFFECTIONATELY
+
+ DEDICATED
+
+
+
+
+PREFACE TO THIRD EDITION
+
+
+Several years have elapsed since the appearance of the second edition of
+this book. During this time there has been considerable experimentation
+and much writing on arteriosclerosis. The total of all work has not been
+to add very much to our knowledge of the etiology of arterial
+degeneration. Points of view and opinions change from time to time. It
+is so with arteriosclerosis. In this edition arteriosclerosis is not
+regarded as a disease with a definite etiologic factor. Rather it is
+looked upon as a degenerative process affecting the arteries following a
+variety of causes more or less ill defined. It is not considered a true
+disease. Possibly syphilitic arteritis may be viewed as an entity, the
+cause is known and the lesions are characteristic.
+
+Much new material and many new figures have been added to this edition.
+Some rearranging has been done. The chapter on Blood Pressure has been
+much expanded and some original observations have been included. The
+literature has been selected rather than indiscriminately quoted. Much
+that is written on the subject is of little value.
+
+It has always seemed to the author that there is not enough of the
+personal element in medical writings. At the risk of being severely
+criticized, he has attempted to make this book represent largely his own
+ideas, only here and there quoting from the literature.
+
+New chapters on Cardiac Irregularities Associated with Arteriosclerosis,
+and Blood Pressure in Its Clinical Application have been added.
+
+The fact that the book has passed through two editions is very
+gratifying and seems to show that it has met with favor. The author
+takes this opportunity of thanking those who have loaned him
+illustrations. Wherever figures are borrowed due credit is given.
+
+It is hoped that the kind of reception accorded to the first and second
+editions will also not be withheld from this present edition.
+
+ LOUIS M. WARFIELD.
+
+ Milwaukee, Wisc.
+
+
+
+
+PREFACE TO THE SECOND EDITION
+
+
+In this second edition so many changes and additions have been made that
+the book is practically a new one. All the chapters which were in the
+previous edition have been carefully revised. Two chapters, "Pathology"
+and "Physiology," have been completely rewritten and brought up to date.
+It was thought best to add some references for those who had interest
+enough to pursue the subject further. These references have been
+selected on account of the readiness with which they may be procured in
+any library, public or private. Two new chapters have been added--one on
+"The Physical Examination of the Heart and Arteries," the other on
+"Arteriosclerosis in Its Relation to Life Insurance," and it is hoped
+that these will add to the practical value of the book.
+
+Arteriosclerosis can scarcely be considered apart from blood pressure,
+and in the view expressed within, with which some may not concur, high
+tension is considered to be a large factor in the production of
+arteriosclerosis. As the data on blood pressure have increased, the
+importance of it has become more evident. The chapter on "Blood
+Pressure" has been wholly rewritten, expanded so as to give a
+comprehensive grasp of the essential features, and several illustrations
+have been added in order to elucidate the text more fully. The chief
+objects in view were to make clear to the physician the technique and
+the necessity for estimating both systolic and diastolic pressures.
+
+The author is grateful for the kindly reception accorded the first
+edition. No one is more keenly aware of the imperfections than he. The
+necessity for a second edition is taken to mean that the book has found
+a place for itself and has been of use to some.
+
+The author hopes that this new edition will fulfill adequately the
+purpose for which he prepared the book--namely, as a practical guide to
+the knowledge and appreciation of a most important and exceedingly
+common disease.
+
+ LOUIS M. WARFIELD.
+
+ Milwaukee, May, 1912.
+
+
+
+
+PREFACE TO THE FIRST EDITION
+
+
+It is hoped that this small volume may fill a want in the already
+crowded field of medical monographs. The author has endeavored to give
+to the general practitioner a readable, authoritative essay on a disease
+which is especially an outcome of modern civilization. To that end all
+the available literature has been freely consulted, and the newest
+results of experimental research and the recent ideas of leading
+clinicians have been summarized. The author has supplemented these with
+results from his own experience, but has thought it best not to burden
+the contents with case histories.
+
+The stress and strain of our daily life has, as one of its consequences,
+early arterial degeneration. There can be no doubt that arterial disease
+in the comparatively young is more frequent than it was twenty-five
+years ago, and that the mortality from diseases directly dependent on
+arteriosclerotic changes is increasing. Fortunately, the almost
+universal habit of getting out of doors whenever possible, and the
+revival of interest in athletics for persons of all ages, have to some
+extent counteracted the tendency to early decay. Nevertheless, the
+actual average prolongation of life is more probably due to the very
+great reduction in infant mortality and in deaths from infectious and
+communicable diseases.
+
+The wear and tear on the human organism in our modern way of living is
+excessive. Hard work, worry, and high living all predispose to
+degenerative changes in the arteries, and so bring on premature old age.
+The author has tried to emphasize this by laying stress on the
+prevention of arteriosclerosis rather than on the treatment of the fully
+developed disease.
+
+No bibliography is given, as this is not intended as a reference book,
+but rather as a guide to a better appreciation and understanding of a
+most important subject. It has been difficult to keep from wandering off
+into full discussions of conditions incident to and accompanied by
+arteriosclerosis, but, in order to be clear in his statements and
+complete in his descriptions, the author has to invade the fields of
+heart disease, kidney disease, brain disease, etc. It is hoped, however,
+that these excursions will serve to show how intimately disease of the
+arteries is bound up with diseases of all the organs and tissues of the
+body.
+
+Some authors have been named when their opinions have been given. Thanks
+are extended also to many others to whom the writer is indebted, but of
+whom no individual mention has been made.
+
+The author also takes this opportunity of expressing his appreciation of
+the kindness of Dr. D. L. Harris, who took the microphotographs, and to
+the publishers for their unfailing courtesy and consideration.
+
+ LOUIS M. WARFIELD.
+
+ St. Louis, August, 1908.
+
+
+
+
+CONTENTS
+
+
+ PAGE
+
+ CHAPTER I
+
+ ANATOMY 25
+
+ Introduction, 25; Definition, 26; General Structure of
+ the Arteries, 27; Arteries, 29; Veins, 30; Capillaries, 31.
+
+ CHAPTER II
+
+ PATHOLOGY 32
+
+ Syphilitic Aortitis, 44; Experimental Arteriosclerosis, 50;
+ Arteriosclerosis of the Pulmonary Arteries, 63; Sclerosis
+ of the Veins, 64.
+
+ CHAPTER III
+
+ PHYSIOLOGY OF THE CIRCULATION 65
+
+ Blood Pressure, 68; Blood Pressure Instruments, 70; Technic,
+ 80; Arterial Pressure, 85; Normal Pressure Variations, 88;
+ The Auscultatory Blood Pressure Phenomenon, 90; The Maximum
+ and Minimum Pressures, 94; Relative Importance of the
+ Systolic and Diastolic Pressures, 97; Pulse Pressure, 100;
+ Blood Pressure Variations, 102; Hypertension, 106;
+ Hypotension, 117; The Pulse, 123; The Venous Pulse, 123;
+ The Electrocardiogram, 126.
+
+ CHAPTER IV
+
+ IMPORTANT CARDIAC IRREGULARITIES ASSOCIATED WITH
+ ARTERIOSCLEROSIS 131
+
+ Auricular Flutter, 131; Auricular Fibrillation, 133;
+ Ventricular Fibrillation, 138; Extrasystole, 138;
+ Heart Block, 140.
+
+ CHAPTER V
+
+ BLOOD PRESSURE IN ITS CLINICAL APPLICATIONS 147
+
+ Blood Pressure in Surgery, 147; Head Injuries, 148; Shock
+ and Hemorrhage, 148; Blood Pressure in Obstetrics, 152;
+ Infectious Diseases, 153; Valvular Heart Disease, 155;
+ Kidney Disease, 155; Other Diseases, Liver, Spleen,
+ Abdomen, etc., 156.
+
+ CHAPTER VI
+
+ ETIOLOGY 157
+
+ Congenital Form, 157; Acquired Form, 159; Hypertension,
+ 159; Age, Sex, Race, 161; Occupation, 162; Food Poisons,
+ 163; Infectious Diseases, 163; Syphilis, 165; Chronic
+ Drug Intoxications, 166; Overeating, 167; Mental Strain,
+ 168; Muscular Overwork, 169; Renal Disease, 169; Ductless
+ Glands, 171.
+
+ CHAPTER VII
+
+ THE PHYSICAL EXAMINATION OF THE HEART AND ARTERIES 172
+
+ Heart Boundaries, 172; Percussion, 174; Auscultation,
+ 176; The Examination of the Arteries, 177; Estimation
+ of Blood Pressure, 179; Palpation, 180; Precautions When
+ Estimating Blood Pressure, 181; The Value of Blood
+ Pressure, 181.
+
+ CHAPTER VIII
+
+ SYMPTOMS AND PHYSICAL SIGNS 183
+
+ General, 183; Hypertension, 185; The Heart, 188; Palpable
+ Arteries, 189; Ocular Signs and Symptoms, 190; Nervous
+ Symptoms, 191.
+
+ CHAPTER IX
+
+ SYMPTOMS AND PHYSICAL SIGNS 194
+
+ Special, 194; Cardiac, 195; Renal, 199; Abdominal or
+ Visceral, 201; Cerebral, 203; Spinal, 205; Local or
+ Peripheral, 207; Pulmonary Artery, 209.
+
+ CHAPTER X
+
+ DIAGNOSIS 210
+
+ Early Diagnosis, 210; Differential Diagnosis, 215;
+ Diseases in Which Arteriosclerosis is Commonly Found, 216.
+
+ CHAPTER XI
+
+ PROGNOSIS 218
+
+ CHAPTER XII
+
+ PROPHYLAXIS 224
+
+ CHAPTER XIII
+
+ TREATMENT 229
+
+ Hygienic Treatment, 230; Balneotherapy, 233; Personal
+ Habits, 234; Dietetic Treatment, 235; Medicinal, 238;
+ Symptomatic Treatment, 245.
+
+ CHAPTER XIV
+
+ ARTERIOSCLEROSIS IN ITS RELATION TO LIFE INSURANCE 249
+
+ CHAPTER XV
+
+ PRACTICAL SUGGESTIONS 256
+
+
+
+
+ILLUSTRATIONS
+
+
+ FIG. PAGE
+
+ 1. Cross section of a large artery 28
+
+ 2. Cross section of a coronary artery 36
+
+ 3. Arteriosclerosis of the thoracic and abdominal aorta 39
+
+ 4. Arteriosclerosis of the arch of the aorta 40
+
+ 5. Normal aorta 41
+
+ 6. Radiogram showing calcification of both radial and ulnar
+ arteries 42
+
+ 7. Syphilitic aortitis of long standing 44
+
+ 8. Diagrammatic representation of strain hypertrophy 48
+
+ 9. Strain hypertrophy 49
+
+ 10. Cross section of small artery in the mesentery 56
+
+ 11. Enormous hypertrophy of left ventricle 58
+
+ 12. Aortic incompetence with hypertrophy and dilatation of
+ left ventricle 61
+
+ 13. Cook's modification of Riva-Rocci's blood pressure
+ instrument 72
+
+ 14. Stanton's sphygmomanometer 73
+
+ 15. The Erlanger sphygmomanometer with the Hirschfelder
+ attachments 74
+
+ 16. Desk model Baumanometer 75
+
+ 17. Faught blood pressure instrument 76
+
+ 18. Rogers' "Tycos" dial sphygmomanometer 77
+
+ 19. Detail of the dial in the "Tycos" instrument 78
+
+ 20. Faught dial instrument 79
+
+ 21. Detail of the dial of the Faught instrument 79
+
+ 22. The Sanborn instrument 80
+
+ 23. Method of taking blood pressure with a patient in sitting
+ position 81
+
+ 24. Method of taking blood pressure with patient lying down 82
+
+ 25. Observation by the auscultatory method and a mercury
+ instrument 84
+
+ 26. Observation by the auscultatory method and a dial instrument 85
+
+ 27. Schema to illustrate decrease in pressure 86
+
+ 28. Chart showing the normal limits of variation in systolic
+ blood pressure 89
+
+ 29. Tracing of auscultatory phenomena 94
+
+ 30. Tracing of auscultatory phenomena 95
+
+ 31. Clinical determination of diastolic pressure, fast drum 96
+
+ 32. Clinical determination of diastolic pressure, slow drum 96
+
+ 33. Venous blood pressure instrument 121
+
+ 34. New venous pressure instrument 122
+
+ 35. Events in the cardiac cycle 124
+
+ 36. Simultaneous tracings of the jugular and carotid pulses 125
+
+ 37. Jugular and carotid tracings 125
+
+ 38. Right side of the heart showing distribution of the
+ two vagus nerves 127
+
+ 39. Normal electrocardiogram 128
+
+ 40. Auricular flutter 132
+
+ 41. Auricular fibrillation 134
+
+ 42. Auricular fibrillation 134
+
+ 43. Pulse deficit 135
+
+ 44. Ventricular fibrillation 137
+
+ 45. Auricular extrasystoles 139
+
+ 46. Ventricular extrasystole 139
+
+ 47. Delayed conduction 141
+
+ 48. Partial heart block 141
+
+ 49. Complete heart block 142
+
+ 50. Alternating periods of sinus rhythm and
+ auriculoventricular rhythm 144
+
+ 51. Auriculoventricular or "nodal" rhythm 144
+
+ 52. Influence of mechanical pressure on the right vagus nerve 144
+
+ 53. Schematic distribution of right and left vagus 145
+
+ 54. Blood pressure record from a normal reaction to ether 149
+
+ 55. Chart showing the method of recording blood pressure
+ during an operation 150
+
+ 56. Method of using blood pressure instrument during operation 151
+
+ 57. Finger-tip palpation of the radial artery 178
+
+ 58. Finger-tip palpation of the radial artery 178
+
+ 59. Aneurysm of the heart wall 196
+
+ 60. Large aneurysm of the aorta eroding the sternum 198
+
+
+
+
+ARTERIOSCLEROSIS AND HYPERTENSION
+
+
+
+
+CHAPTER I
+
+ANATOMY
+
+
+With the increased complexity of our modern life comes increased wear
+and tear on the human organism. "A man is as old as his arteries" is an
+old dictum, and, like many proverbs, the application to mankind today
+is, if anything, more pertinent than it was when the saying was first
+uttered. Notwithstanding the fact that the average age of mankind at
+death has been materially lengthened--the increase in years amounting to
+fourteen in the past one hundred years of history--clinicians and
+pathologists are agreed that the arterial degeneration known as
+arteriosclerosis is present to an alarming extent in persons over forty
+years of age. Figures in all vital statistics have shown us that all
+affections of the circulatory and renal systems are definitely on the
+increase. "Arterial diseases of various kinds, atheroma, aneurysm, etc.,
+caused 15,685 deaths in 1915, or 23.3 per 100,000. This rate, although
+somewhat lower than the corresponding ones for 1912 and 1913, is higher
+than that for 1914, and is very much higher than that for 1900, which
+was 6.1."
+
+The great group of cases of which cardiac incompetence, aneurysm,
+cerebral apoplexy, chronic nephritis, emphysema, and chronic bronchitis
+are the most frequent and important appear as terminal events in which
+arteriosclerosis has probably played an important part.
+
+Thus, in the sense in which we speak of tuberculosis or pneumonia as a
+distinct disease, we can not so designate the diseased condition of the
+arteries.
+
+Arteriosclerosis is not a disease =sui generis=. It is best viewed as a
+degeneration of the coats of the arteries, both large and small
+resulting in several different more or less distinct types.
+
+These types blend one into the other and in the same patient all types
+may be found. Thus the sclerosis of the arteries is the result of a
+variety of causes, none of which is definitely known in the sense of a
+bacterial disease. As we shall see later, one type of arteriosclerosis
+has a special pathology and etiology, the syphilitic arterial changes.
+
+Bearing in mind that arteriosclerosis (called by some "arteriocapillary
+fibrosis," by others "atherosclerosis") is not a true disease, it may,
+for convenience be defined as a chronic disease of the arteries and
+arterioles, characterized anatomically by increase or decrease of the
+thickness of the walls of the blood vessels, the initial lesion being a
+weakening of the middle layer caused by various toxic or mechanical
+agencies. This weakness of the media leads to secondary effects, which
+include hypertrophy or atrophy of the inner layer--and not infrequently
+hypertrophy of the outer layer--connective tissue formation and
+calcification in the vessels, and the formation of minute aneurysms
+along them. The term arteriocapillary fibrosis has a broader meaning,
+but is a cumbersome phrase, and conveys the idea that the capillary
+changes are an essential feature of the process, whereas these are for
+the most part secondary to the changes in the arteries. The veins do not
+always escape in the general morbid process, and when these are affected
+the whole condition is sometimes called vascular sclerosis or
+angiosclerosis.
+
+Upon the anatomical structure of the arteries depends, as a rule, the
+character and extent of the arteriosclerotic lesions. For the clear
+comprehension of the process, it is necessary to keep in mind the
+essential histological differences between the aorta and the larger and
+smaller branches of the arterial tree.
+
+The vascular system is often likened to a central pump, from which
+emanates a closed system of tubes, beginning with one large
+distributing pipe, which gives rise to a series of tubes, whose number
+is constantly increasing at the same time that their caliber is
+decreasing in size. From the smallest of these tubes, larger and larger
+vessels collect the flowing blood, until, at the pump, two large trunks
+of approximately the same area as the one large distributing trunk empty
+the blood into the heart, thus completing the circle. This is but a
+rough illustration, and, while possibly useful, takes into account none
+of the vital forces which are constantly controlling every part of the
+distributing system.
+
+
+General Structure of the Arteries
+
+The aorta and its branches are highly elastic tubes, having a smooth,
+glistening inner surface. When the arteries are cut open, they present a
+yellowish appearance, due to the large quantity of elastic tissue
+contained in the walls. The elasticity is practically perfect, being
+both longitudinal and transverse. The essential portion of any blood
+vessel is the endothelial tube, composed of flat cells cemented together
+by intercellular substance and having no stomata between the cells. This
+tube is reinforced in different ways by connective tissue, smooth muscle
+fibers, and fibroelastic tissue. Although the gradations from the larger
+to the smaller arteries and from these to the capillaries and veins are
+almost insensible, yet particular arteries present structural characters
+sufficiently marked to admit of histological differentiation.
+
+The whole vascular system, including the heart, has an endothelial
+lining, which may constitute a distinct inner coat, the tunica intima,
+or may be without coverings, as in the case of the capillaries. The
+intima (Fig. 1) consists typically of endothelium, reinforced by a
+variable amount of fibroelastic tissue, in which the elastic fibers
+predominate. The tunica media is composed of intermingled bundles of
+elastic tissue, smooth muscle fibers, and some fibrous tissue. The
+adventitia or outer coat is exceedingly tough. It is usually thinner
+than the media, and is composed of fibroelastic tissue. This division
+into three coats is, however, somewhat arbitrary, as in the larger
+arteries particularly it is difficult to discover any distinct
+separation into layers.
+
+[Illustration: Fig. 1.--Cross section of a large artery showing the
+division into the three coats; intima, media, adventitia. The intima is
+a thin line composed of endothelial cells. The wavy elastic lamina is
+well seen. The thick middle coat is composed of muscle fibers and
+fibroelastic tissue. The loose tissue on the outer (lower portion of
+cut) side of the media is the adventitia. (Microphotograph, highly
+magnified.)]
+
+The muscular layer varies from single scattered cells, in the
+arterioles, to bands of fibers making up the body of the vessel in the
+medium-sized arteries and veins.
+
+There is elastic tissue in all but the smallest arteries, and it is also
+found in some veins. It varies in amount from a loose network to dense
+membranes. In the intima of the larger arteries the elastic tissue
+occurs as sheets, which under the microscope appear perforated and
+pitted, the so-called fenestrated membrane of Henle.
+
+The nutrient vessels of the arteries and veins, the vasa vasorum, are
+present in all the vessels except those less than one millimeter in
+diameter. The vasa vasorum course in the external coat and send
+capillaries into the media, supplying the outer portion of the coat and
+the externa with nutritive material. The nutrition of the intima and
+inner portion of the media is obtained from the blood circulating
+through the vessel. Lymphatics and nerves are also present in the middle
+and outer layers of the vessels.
+
+
+Arteries
+
+The structure of the arteries varies notably, depending upon the size of
+the vessel. A cross section of the thoracic aorta reveals a dense
+network of elastic fibers, occupying practically all of the space
+between the single layer of endothelial cells and the loose elastic and
+connective tissue network of the outer layer. Smooth muscle fibers are
+seen in the middle coat, but, in comparison with the mass of elastic
+tissue, they appear to have only a limited function.
+
+In a cross section of the radial artery one sees a wavy outline of
+intima, caused by the endothelium following the corrugations of the
+elastica. The endothelium is seen as a delicate line, in which a few
+nuclei are visible. The media is comparatively thick, and is composed of
+muscle cells, arranged in flat bundles, and plates of elastic tissue.
+Between the media and the externa the elastic tissue is somewhat
+condensed to form the external elastic membrane. The adventitia varies
+much in thickness, being better developed in the medium-sized than in
+the large arteries. It is composed of fibrous tissue mixed with elastic
+fibers.
+
+"Followed toward the capillaries, the coats of the artery gradually
+diminish in thickness, the endothelium resting directly upon the
+internal elastic membrane so long as the latter persists, and afterward
+on the rapidly attenuating media. The elastica becomes progressively
+reduced until it entirely disappears from the middle coat, which then
+becomes a purely muscular tunic, and, before the capillary is reached,
+is reduced to a single layer of muscle cells. In the precapillary
+arterioles the muscle no longer forms a continuous layer, but is
+represented by groups of fiber cells that partially wrap around the
+vessel, and at last are replaced by isolated elements. After the
+disappearance of the muscle cells the blood vessel has become a true
+capillary. The adventitia shares in the general reduction, and gradually
+diminishes in thickness until, in the smallest arteries, it consists of
+only a few fibroelastic strands outside the muscle cells." (Piersol's
+Anatomy.)
+
+The large arteries differ from those of medium size mainly in the fact
+that there is no sharp line of demarcation between the intima and the
+media. There is also much more elastic tissue distributed in firm
+bundles throughout the media, and there are fewer muscle fibers, giving
+a more compact appearance to the artery as seen in cross section. The
+predominance of elastic tissue permits of great distention by the blood
+forced into the artery at every heartbeat, the caliber of the tube being
+less markedly under the control of the vasomotor nerves than is the case
+in the small arteries, where the muscle tissue is relatively more
+developed. The adventitia of the large arteries is strong and firm, and
+is made up of interlacing fibroelastic tissue, of which some of the
+bundles are arranged longitudinally.
+
+
+Veins
+
+The walls of the veins are thinner than those of the arteries; they
+contain much less elastic and muscular tissue, and are, therefore, more
+flaccid and less contractile. Many veins, particularly those of the
+extremities, are provided with cup-like valves opening toward the heart.
+These valves, when closed, prevent the return of the blood to the
+periphery and distribute the static pressure of the blood column. The
+bulgings caused by the valves may be seen in the superficial veins of
+the arm and leg. There are no valves in the veins of the neck, where
+there is no necessity for such a protective mechanism, gravity sufficing
+to drain the venous blood from the cranial cavity.
+
+
+Capillaries
+
+These are endothelial tubes in the substance of the organs, the tissue
+of the organ giving them the necessary support. They are the final
+subdivisions of the blood vessels, and the vast capillary area offers
+the greatest amount of resistance to the blood flow, thus serving to
+slow the blood stream and allowing time for nutritive substances or
+waste products to pass from and to the blood. Usually the capillaries
+are arranged in the form of a network, the channels in any one tissue
+being of nearly uniform size, and the closeness of the mesh depending
+upon the organ.
+
+As far back as 1865, Stricker observed contraction of the capillaries.
+This observation was apparently forgotten until revived again by Krogh
+recently. The latter finds that the capillaries are formed of cells
+which are arranged in strands encircling the vessel. The capillaries are
+rarely longer than 1 mm., and, according to Krogh, are capable of
+enormous dilatation.
+
+The rate of flow through any capillary area is very inconstant, and the
+usual explanation has been that the capillaries were endothelial tubes
+the blood flow of which was dependent upon the contraction or dilatation
+of the terminal arterioles. The actual fact that in an observed
+capillary area some capillaries are empty renders the above explanation
+untenable. The color of a tissue depends upon the state of filling of
+the capillaries with blood.
+
+It would seem that all the evidence now leads us to believe that the
+capillaries themselves are contractile and it is even possible that they
+may be under vasomotor control. If the anatomic structure as stated
+above, is correct, it would take but a slight contraction of the
+encircling cell to shut off completely the capillary. When the enormous
+capillary bed is considered, it is not inconceivable that circulating
+poisons may act on large areas and produce a true capillary resistance
+to the onflow of blood which might express itself, if long continued, in
+actual hypertrophy of the heart.
+
+
+
+
+CHAPTER II
+
+PATHOLOGY
+
+
+The whole subject of the pathology of arteriosclerosis has been much
+enriched by the study of the experimental lesions produced by various
+drugs and microorganisms upon the aortas of rabbits. Simple atheroma
+must not be confused with the lesions of arteriosclerosis. The small
+whitish or yellowish plaques so frequently seen on the aorta and its
+main branches, may occur at any age, and have seemingly no great
+significance. Such plaques may grow to the size of a dime or larger, and
+even become eroded. They represent fatty degeneration of the intima
+which, at times, has no demonstrable cause; at times follows in the
+course of various diseases, and undoubtedly is due to disturbances of
+nutrition in the intima. Except for the remote danger of clot formation
+on the uneven or eroded spot, these places are of no special
+significance, and are not to be confused with the atheroma of nodular
+sclerosis.
+
+The lesions of arteriosclerosis are of a different character. It has
+been customary to differentiate three types: (1) nodular; (2) diffuse;
+(3) senile. It must be understood that this is not a classification of
+distinct types. As a rule in advanced arteriosclerosis, lesions
+representing all types and all grades are found. The nodular type,
+however, may occur in the aorta alone, the branches remaining free. This
+is most often found in syphilitic sclerosis where the lesion is confined
+to the ascending portion of the arch of the aorta.
+
+The retrogressive changes of advancing years can not be rightly termed
+disease, yet it becomes necessary to regard them as such, for the senile
+changes, as we shall see, may be but the advanced stages of true
+arteriosclerosis. Much depends on the nature of the arterial tissue and
+much on the factors at work tending to injure the tissue. A man of
+forty years may therefore have the calcified, pipe stem arteries of a
+man of eighty. Our parents determine, to great extent, the kind of
+tissue with which we start life. The arteries are elastic tubes capable
+of much stretching and abuse. In the aorta and large branches there is
+much elastic tissue and relatively little muscle. When the vessels have
+reached the organs, they are found to be structurally changed in that
+there is in them a relatively small amount of elastic tissue but a great
+deal of smooth muscle. This is a provision of nature to increase or
+decrease the supply of blood at any point or points.
+
+The aorta and the large branches are distributing tubes only. It is
+after all in the arterioles and smaller arteries that the lesions of
+arteriosclerosis do the most damage. A point to be emphasized is that
+the whole arterial system is rarely, if ever, attacked uniformly. That
+is, there may be a marked degree of sclerosis in the aorta and coronary
+arteries with very little, if any, change in the radials. On the
+contrary, a few peripheral arteries only may be the seat of disease. A
+case in point was seen at autopsy in which the aorta in its entirety and
+all the large peripheral branches were absolutely smooth. In the brain,
+however, the arteries were tortuous, hard, and were studded with miliary
+aneurysms. It is not possible to judge accurately the state of the whole
+arterial system by the stage of the lesion in any one artery; but on the
+whole one may say that an undue thickening of the radial artery
+indicates analogous changes in the mesenteric arteries and in the aorta.
+
+So far as the anatomical lesions in the aorta and branches are
+concerned, there is much uniformity even though the etiologic factors
+have been diverse. The only difference is one of extent. To Thoma we owe
+the first careful work on arteriosclerosis. He regarded the lesion in
+arteriosclerosis as one situated primarily in the media; there is a lack
+of resistance in this coat. His views are now chiefly of historical
+interest. As the author understands him, he considered a rupture in the
+media to be the cause of a local widening and consequently the blood
+could not be distributed evenly to the organ which was supplied by the
+diseased artery or arteries. Moreover, there was danger of a rupture at
+the weak spot unless this were strengthened. It was essential for the
+even distribution of blood that the lumen be restored to its former
+size. Nature's method of repair was a hypertrophy of the subintimal
+connective tissue and the formation of a nodule at that point. The
+thickening was compensatory, resulting in the establishment of the
+normal caliber of the vessel. Thoma showed that by injecting an aorta in
+the subject of such changes, with paraffin at a pressure of 160 mm. of
+mercury, these projections disappeared and the muscle bulged externally.
+He recognized the fact that the character of the artery changed as the
+years passed, and to this form he gave the name, primary
+arteriosclerosis. To the group of cases caused by various poisonous
+agents, or following high peripheral resistance and consequent high
+pressure, he gave the name, secondary arteriosclerosis. This is a useful
+but not essential division, as the changes which age and high tension
+produce may not be different from those produced in much younger persons
+by some circulating poison. And most important to bear in mind,
+octogenarians may have soft, elastic arteries.
+
+As the body ages, certain changes usually take place in the arteries
+leading to thickening and inelasticity of their walls. This is a normal
+change, and in estimating the palpable thickening of an artery, such as
+the radial, the age of the individual must always be considered.
+
+Thayer and Fabyan, in an examination of the radial artery from birth to
+old age, found that, in general, the artery strengthens itself, as more
+strain is thrown upon it, by new elastica in the intima and connective
+tissue in the media and adventitia. Up to the third decade there is
+only a strengthening of the media and adventitia. During the third and
+fourth decades there is also distinct connective tissue thickening in
+the intima. "In other words, the strain has begun to tell upon the
+vessel wall, and the yielding tube fortifies itself by the connective
+tissue thickening of the intima and to a lesser extent of the media." By
+the fifth decade the connective tissue deposits in the intima are
+marked, there is an increase of fibrous tissue upon the medial side of
+the intima and, in lesser degree, throughout the media. "Finally, in
+these sclerotic vessels degenerative changes set in, which are somewhat
+different from those seen in the larger arteries, consisting, as they
+do, of local areas of coagulation necrosis with calcification,
+especially marked in the deep layers of the connective tissue
+thickenings of the intima, and in the muscle fibers of the media,
+particularly opposite these points. These changes may ... go on to
+actual bone formation." The mesenteric artery differs in some respects
+from the radial, but in the main, the changes brought about by age are
+the same. Thayer and Fabyan note two striking points of difference: "(1)
+calcification is apparently much less frequent than in the radials; (2)
+in several cases plaques were seen with fatty softening of the deeper
+layers of the intima and superficial proliferation--a picture which we
+have never seen in the radial." (See Fig. 2.)
+
+[Illustration: Fig. 2.--Cross-section of a coronary artery, x50, showing
+nodular sclerosis. Note the heaping up of cells in the intima, the
+fracture of the elastica, and the destruction of the media beneath the
+nodule. The primary lesion evidently was in the media. The thickened
+intima is the effort on the part of nature to heal the breach. At such
+places as shown here aneurysms may form. (Microphotograph.)]
+
+Aschoff's studies of the aorta show that, "in infancy the elastic laminæ
+of the media stand out sharply defined, well separated from each other
+by the muscle layers, which are well developed.... From childhood there
+is to be observed a slowly progressive increase in the elastic elements
+of the media. Not only do the individual lamellæ seen in cross-sections
+become thicker, but also they afford an increasing number of fine
+secondary filaments feathering off from these and crossing the muscle
+layer, so that now they are no longer sharply defined, but more ragged
+upon cross-section. This progressive increase attains its maximum at or
+about the age of thirty-five, and from now on for the next fifteen
+years the condition is relatively stationary. After fifty there is to be
+observed a slowly progressive atrophy of the elastica. The media becomes
+obviously thinner and presumably weaker." (Adami.) It has also been
+found (Klotz) that after the age of thirty-five, the muscle of the media
+begins to exhibit fatty degeneration which after fifty years is well
+marked. The fatty degeneration may then give place to a calcareous
+infiltration or the fibers may undergo complete absorption. It would
+appear that the thinning of the aortic media is due not so much to the
+atrophy of the elastic tissue as to that of the muscle tissue. The
+elastic tissue does lose its specific property and the artery thus
+becomes practically a connective tissue tube.
+
+Scheel has made very careful measurements of the ascending, the
+thoracic, and the abdominal aorta, and the pulmonary artery. He found
+that from birth to sixty years, the aorta became progressively wider and
+lost its elasticity. The pulmonary changed little, if at all, after
+thirty to forty years, and where before it was wider than the aorta, it
+now was found to be smaller. In chronic nephritis both were widened. The
+continuous increase of width and length of the aorta stands in reverse
+relationship to the elasticity of its walls.
+
+Although the division of the lesions into nodular, diffuse, and senile
+has been the usual one, it is better to separate three groups into (1)
+nodular, (2) diffuse or senile, and (3) syphilitic. There is more known
+about the histology of the syphilitic form and the lesions which consist
+of puckerings and scars seen on opening an aorta just above the valves,
+and on the ascending portion of the arch are characteristic. A
+macroscopic examination suffices in most cases for a definite diagnosis.
+
+In the nodular form the lesions are found on the aorta and large
+branches particularly at or near the orifices of branching vessels.
+These nodules may increase in size, forming rather large, slightly
+raised plaques of yellowish-white color. They are, as a rule,
+irregularly scattered throughout the aorta and branches and tend to be
+more numerous and larger in the abdominal aorta. The initial lesion is
+in the media, consisting of an actual dissolution of this coat with
+rupture of the elastic fibers and infiltration with small round cells.
+There is thus a weak spot in the artery. Hypertrophy of the intimal
+cells takes place, layer upon layer being added in an attempt to
+strengthen the vessel at the injured place. Coincidently with this,
+there is thickening by a connective tissue growth in the adventitia. The
+process begins, at least in syphilis, around the terminals of the vasa
+vasorum. It will be recalled that the blood supply of the inner portion
+of the media comes from within the vessel itself. As the intimal growth
+increases, the blood supply is cut off. The inevitable result is
+softening of the portion farthest from the lumen of the vessel. As a
+rule there has been a sufficient growth of connective tissue in the
+media and adventitia to repair the damage done to the media. This
+softening and dissolution gives rise to a granular debris composed of
+degenerated cells and fat. This is the so-called atheromatous abscess.
+There are no leucocytes as in ordinary pus. These "abscesses" are
+frequent and in rupturing leave open ulcers with smooth bases, the
+atheromatous ulcer. A further change which often takes place is
+calcification of the bases of the ulcers and calcification of the
+softened spots before rupture takes place. This only occurs in advanced
+cases. (See Fig. 3.)
+
+[Illustration: Fig. 3.--Arteriosclerosis of the thoracic and abdominal
+aorta, showing irregular nodules, atheromatous plaques, denudation of
+the intima, thin plates of bone scattered throughout with spicules
+extending into the lumen of the vessel. Note the contraction of the
+openings of the large branches, the rough appearance of the aorta and
+the greater degree of sclerosis of the upper two-thirds, i. e., of the
+aorta above the diaphragm. This aorta in the recent state was much
+thickened and almost inelastic.]
+
+[Illustration: Fig. 4.--Arteriosclerosis of the arch of the aorta.
+Numerous calcified plaques, thickening and curling of the aortic valves,
+giving rise to insufficiency of the aortic valves. The aortic ring is
+rigid and not much dilated. (Milwaukee County Hospital.)]
+
+[Illustration: Fig. 5.--Normal aorta. Compare with Fig. 3. Note the
+perfectly smooth, glossy appearance of the intima. The openings of all
+the intercostal arteries are distinctly seen. In the recent state this
+artery was highly elastic, capable of much stretching both transversely
+and longitudinally.]
+
+Rather contrary to what one would expect, there are no new capillaries
+advancing from the media to the intima in the nodular form of
+arteriosclerosis, consequently there is no granulation tissue to heal
+and leave scars. It must be borne in mind that these changes rarely, if
+ever, are the only ones found throughout the arterial system.
+Nevertheless, the manifold changes, as will be shown within, appear to
+be but stages of one primary process.
+
+The character of the changes which are known as diffuse arteriosclerosis
+seems to have, at first sight, little in common with those of the
+nodular sclerosis. The aorta may or may not have plaques of nodular
+sclerosis, while the arteries, such as the radial or temporal, may be
+beaded or pipe stem in hardness. In spite of these far advanced
+peripheral lesions the aorta may appear smooth but it is markedly
+dilated, particularly the thoracic portion, it is noticeably thinned
+even on macroscopic examination, it has elongated as evidenced by its
+slight tortuosity, and it has lost the greater part of its elasticity.
+The abdominal aorta is not so extensively affected, although this, too,
+shows some elongation and slight thinning. This is considered by some
+pathologists to be the uncomplicated form of the so-called senile
+arteriosclerosis. It is more of the nature of a degenerative change, it
+is true, but, as will be shown later, it has its beginnings, at times,
+in comparatively young persons and its etiology is not simple. This
+type has been studied most carefully by Moenckeberg, who showed that on
+the large branches of the aorta there were depressions due to a
+degeneration of the middle coat. These depressions encircled the vessel
+to a greater or lesser extent, causing small bulgings at such places
+and giving to the vessel a beaded appearance. On viewing such an artery
+held to the light, the sacculated spots are seen to be much thinner than
+the contiguous normal artery. Associated with such changes in the aorta
+and large branches is marked sclerosis of the smaller arteries. Intimal
+fibrosis is common, together with hypertrophy and fibrosis of the middle
+coat. Not infrequently periarterial thickening is also seen.
+Calcification of the media is found and is said to be preceded by
+hypertrophy of the middle coat.
+
+Pure cases of this, the so-called Moenckeberg type, are seen but seldom.
+Most commonly there are nodules and plaques in the aorta and large
+branches together with thinning and sacculation of other portions of the
+vessels' walls. While the two processes appear at a glance to be so
+different from each other, it is possible for them to have a common
+origin. The initial lesion is in the media but the resulting sclerotic
+changes depend upon the kind of vessel, the strength of the coats, the
+pressure in the vessel, and other causes.
+
+Thus the sclerosis of the radials of such an extent that these arteries
+are easily palpable, appears to be a different process from that of the
+sclerosis in the aorta, yet fundamentally it is the same. The difference
+lies in the anatomic structure of the two vessels, and possibly also in
+the degree of stretching and strain to which the vessels are subjected
+at every heart beat. In the radial artery the media as usual is affected
+first. The muscle cells undergo degeneration and either marked
+thickening takes place or sacculation results, depending upon the
+severity of the exciting cause. Calcification of the media is common.
+This occasionally takes the form of rings encircling the vessel, and
+gives to the examining finger the sensation of feeling a string of fine
+beads. There may be calcification of the subintimal tissue without
+deposits of lime salts in the media, but this is more commonly found in
+the larger arteries. When the calcification occurs in plates through the
+media, the well known pipe stem vessel is produced. (Fig. 6.)
+
+[Illustration: Fig. 6.--Radiogram of a man aged seventy-five, showing
+calcification of both radial and ulnar arteries.]
+
+The senile sclerosis found in old people is usually a combination of the
+Moenckeberg type in the large and medium-sized arteries, and the nodular
+type in the aorta, leading eventually to calcareous intimal deposits,
+and widened, elongated, inelastic aorta.
+
+
+=Syphilitic Aortitis=
+
+[Illustration: Fig. 7.--Syphilitic aortitis of long standing. The aortic
+valves are curled and thickened, the heart is enlarged and the cavity of
+the left ventricle is dilated. (Milwaukee County Hospital.)]
+
+The seat of election of the syphilitic poison is in the aorta just above
+the aortic valves, Fig. 7, and in the ascending portion of the arch.
+There are semitranslucent, hyaline-like plaques which have a tendency to
+form into groups and, instead of undergoing an atheromatous change as
+in the ordinary nodular form of arteriosclerosis, they are prone to scar
+formation with puckering, so that macroscopically the nature of the
+process may, as a rule, be readily diagnosed. Microscopically the
+process is found to be a subacute inflammation of the media, which has
+been called a mesaortitis. There is marked small celled infiltration
+around some of the branches of the vasa vasorum and there appears to be
+actual absorption of the tissue elements of the middle coat. This is
+accompanied by hypertrophy of the intimal tissue. There follows
+degeneration in the deeper portions of this new tissue and new
+capillaries are formed which have their origin in the inflammatory area
+in the media. As is everywhere the case throughout the body, granulation
+tissue in the process of healing contracts and forms scars. This
+explains the scar formation in the aorta. When the process is more
+acute, instead of there being a reparative attempt on the part of the
+intima, there is actual stretching of the wall at the weakened spot and
+there results an aneurysmal dilatation. =Spirochetæ pallidæ= have been
+found in the degenerated media and in small gummata which were situated
+beneath the intima. Within the past years it has been found that a large
+percentage of patients with cardiovascular disease give the Wassermann
+reaction. In cases of aortic insufficiency, the reaction is present in
+almost every case. This is in marked contrast to the cases of diffuse
+endocarditis where the reaction is rarely present.
+
+According to Adami the effects of syphilis upon the aorta are the
+following: (1) the primary disturbance is a granulomatous, inflammatory
+degeneration of the media; (2) this leads to a local giving way of the
+aorta; (3) if this be moderate it results in a strain hypertrophy of the
+intima and of the adventitia, with the development of a nodose intimal
+sclerosis; (4) if it be extreme, there results, on the contrary, an
+overstrain atrophy of the intima and aneurysm formation; (5) the intimal
+nodosities are here not of an inflammatory type and are nonvascular,
+although, with the progressive laying down of layer upon layer of
+connective tissue on the more intimal aspect of the intima, the earlier
+and deeper-placed layers of new tissue gain less and less nourishment,
+and so are liable to exhibit fatty degeneration and necrosis; (6) these
+products of necrosis exert a chemotactic influence upon the nearby
+vessels of the medial granulation tissue, with, as a result, (a) a
+secondary and late entrance of new vessels into the early and
+deeply-placed atheromatous area, (b) absorption of the necrotic
+products, (c) replacement by granulation tissue, (d) contraction of the
+granulation tissue, and (e) depression and scarring of the sclerotic
+nodules so characteristic of syphilitic sclerosis.
+
+In the smaller arteries and arterioles the arteriosclerotic process
+appears on superficial examination to be a different process from that
+in the aorta and large arteries, but the difference is only apparent. It
+will be recalled that there is relatively much more muscle tissue in the
+arterioles than in the large arteries. The size, of course, is much
+less. Large nodular plaques are not possible. The atheromatous
+degeneration is not marked. In the smaller muscular arteries is seen the
+intimal proliferation, the stretching of the Moenckeberg type, and the
+calcification of the media rather than the intima. The media is thinned
+beneath the marked intimal proliferation so that the artery exhibits
+translucent areas when held to the light. Again, there is seen
+degeneration of the muscle and replacement by connective tissue with or
+without hypertrophy of the intima. In the arterioles three kinds of
+changes occur: a muscular hypertrophy; a fibrosis of all the coats; or a
+marked proliferation of the intimal endothelium. The last two are
+probably the same process, the connective tissue having its origin in
+the proliferated endothelial cells. Such a deposition of layer upon
+layer of cells in an arteriole and the resulting fibrosis leads to the
+condition of disappearance of the lumen of the vessel, endarteritis
+obliterans. This obliterating endarteritis is not, of course, due alone
+to syphilis. Syphilis is only a type of poison which produces such
+changes as have been described above. It is in the organs such as the
+kidney, liver, spleen, and intestines that one sees the most perfect
+examples of this obliterating endarteritis. Endarteritis deformans is a
+term applied to the condition of the arteries as a result of irregular
+thickenings and deposits of lime salts in the walls. These changes give
+rise to marked tortuosity of the vessels.
+
+Occasionally such an obliterating process takes place in a larger
+artery. A thrombus forms and by a process of central softening, new
+channels permeate the thrombus, thus restoring to some extent the
+function of the vessel.
+
+That the same process leads at one time to thinning and at another time
+to thickening of the arterial walls has been noted above. Prof. Adami
+holds that the regular development of layer upon layer of new connective
+tissue is non-inflammatory. He calls it a "strain hypertrophy." It is
+analogous to the localized hypertrophy of bone where the muscle tendons
+are attached, as is so frequently seen in athletes. The increased
+tension on connective tissue, provided that it is not overstrained,
+leads to its overgrowth, but only when there is sufficient nourishment.
+Such conditions are adequately fulfilled in the arteries. When a local
+giving way under pressure occurs in the media, the intima is put on the
+stretch (see Fig. 8), and there results a hypertrophy of the intima
+until the volume of the new tissue and the resistance which this affords
+to the mean distending force, balances the loss sustained by the
+weakened media. When the balance is struck, the hypertrophy is arrested.
+The youngest tissue is thus found directly beneath the endothelium. Now
+should this local weakening of the media have an acute origin, instead
+of a stimulus to growth there is overstrain, and there is, in
+consequence, not hypertrophy but atrophy. The beginning process is here
+a mesaortitis, but the acuteness of the poison, and the pressure from
+within the artery so stretches the artery that there is no compensatory
+hypertrophy, but a thinning, and the ground is prepared for aneurysmal
+dilatation or pouching.
+
+[Illustration: Fig. 8.--I, media weakened at M' with overgrowth of
+intima filling in the depression. II, with postmortem rigor and
+contraction of the muscles of the media and removal of the blood
+pressure from within, the stretched media at M'' contracts; the intimal
+thickening thus projects into the arterial lumen. (After Adami.)]
+
+Again, one not infrequently encounters intimal nodosities when the
+underlying media appears of normal thickness. The explanation of this
+apparent exception is that the media in the living aorta is actually
+thinned, but the layers of subintimal tissue deposited over the weak
+spot due to strain hypertrophy become bulged inward when the pressure is
+relieved, as at postmortem. The media has not lost all of its elasticity
+(see Fig. 9), hence it contracts and there is the appearance of a nodule
+on the intima beneath which is a media equal in thickness to that of the
+healthy surrounding media.
+
+[Illustration: Fig. 9.--Schematic representation of the increased strain
+brought to bear upon the cells of the intima, Int., when the media,
+Med., undergoes a localized expansion through relative weakness. (After
+Adami.)]
+
+The essential lesion in arteriosclerosis of the aorta and large arteries
+is a degeneration in the middle coat. This may be brought about by a
+variety of poisons circulating in the body. In syphilis, for example,
+the initial lesion has been shown to be a mesaortitis. The media seems
+to be dissolved, the artery is consequently thinned, there is actual
+depression along the level of the vessel. The elastic fibers disappear
+and small-celled infiltration takes its place. The intima hypertrophies,
+layer upon layer being added in an attempt to restore the strength of
+the vessel. There is also, as a rule, rather pronounced hypertrophy of
+the adventitia.
+
+
+=Experimental Arteriosclerosis=
+
+Within the past few years many workers have attempted by various means,
+to produce arterial lesions in animals, chiefly rabbits and dogs. The
+present status is somewhat chaotic, some affirming and some denying that
+arterial changes follow the various methods employed. Following the
+injection of small, repeated doses of adrenalin over a certain period of
+time, changes occur in the arteries of rabbits which are
+arteriosclerotic in type, the essential lesion being a degeneration of
+the muscular and elastic tissue of the media with the consequent
+production of aneurysm in the vessel. This is said by some to be quite
+like the type of arteriosclerosis in man which has been so well
+described by Moenckeberg. The degenerations in the arteries following
+the experimental lesions are of the nature of a fatty metamorphosis, and
+later proceed to calcification. Barium chloride, digitalin,
+physostigmin, nicotin and other substances, as well as adrenalin, have
+been found to exert a selective toxic action on the muscle cells of the
+middle coat of the aorta. The infundibular portion of the pituitary
+body, the portion which is developed from the infundibulum of the brain,
+possesses an internal secretion, which, injected intravenously, causes a
+marked rise of blood pressure and slowing of the heart beat. So far as I
+know, this active principle of the gland has not been used in an attempt
+to produce experimentally the lesions of arteriosclerosis.
+
+Wacker and Hueck succeeded in producing aortic disease in rabbits which
+they considered to be in many points quite like human arteriosclerosis.
+They injected the rabbits intravenously with cholesterin. They feel that
+this is of great importance in view of the fact that exercise (muscle
+metabolism) dyspnea, certain poisons, as well as adrenalin, and even
+adrenal extirpation occasion a high cholesterin content of the blood.
+Anitschow's experiments are confirmatory. He fed rabbits on large
+amounts of cholesterin-containing substances (yolk of egg, brain
+tissue) and pure cholesterin and found changes in the intima and inner
+portion of the media consisting of fatty infiltration between the muscle
+and elastic fibres, advent of small round cells and large phagocytic
+cells containing fat droplets of cholesterin esters. The elastic fibres
+were dissolved, broken up into fibrillæ and these seemed to be absorbed.
+The internal elastic lamina as such disappeared and the inner layer of
+the aorta fused with the middle coat. He considers these changes to be
+quite analogous to those found in human aortas.
+
+Oswald Loeb produced changes in the arteries of rabbits by feeding them
+sodium lactate (lactic acid). His controls fed on other acids became
+cachectic, but showed no arterial changes. He further found that in 100
+gm. of human blood there was normally from 15 to 30 mg. of lactic acid.
+After heavy work, he found as much as 150 gm. He considers that after
+adrenalin or nicotin injections, the function of the liver is so
+disturbed that lactic acid is not bound. The arteriosclerosis is
+actually due to the presence of free lactic acid in the circulation. He
+succeeded, also, in producing lesions of the intima in a dog fed for a
+long time on protein poor diet, plus lactic acid and sodium lactate.
+
+Another investigator, Steinbiss, fed rabbits on animal proteins only, a
+diet totally foreign to their natural habits. He succeeded, however, in
+keeping some alive for three months. He also tried various substances
+and in the general conclusions says that no aortic changes could be
+produced in animals kept in natural living conditions by any mechanical
+means, increase of blood pressure, digital compression, hanging by hind
+legs, etc. In infectious diseases, especially septic, widespread
+sclerotic changes occurred in the aorta. A most suggestive conclusion in
+this "the most important result of feeding rabbits with animal proteins
+is, along with a constant glycosuria, disease of the aorta and
+peripheral arteries which is identical with changes in the aorta
+produced by injections of adrenalin. The degree of disease of the
+circulatory system increases with the duration of the experiment."
+
+By a small addition of vegetable to the protein diet, the lives of the
+animals were prolonged at will. With this modification of the
+experiment, the findings in the vessel walls were noticeably altered.
+The changes affected chiefly the intima, to less degree the media, and
+histologically were very much like human intimal disease.
+
+I have been unable to produce the slightest arterial lesions in rabbits
+by intravenous injections of lead. Frothingham had no success feeding
+animals with lead. In a study of autopsy material from persons up to 40
+years, who died of infectious disease, he found changes in the arteries
+of those who had succumbed to infection with the pus cocci or to very
+severe infectious disease. These changes were, however, localized, and
+were not like those of the general diffuse arteriosclerosis.
+
+Adler has recently reported experiments on dogs, to which he fed or
+injected intravenously various substances supposed to induce
+arteriosclerotic changes. He was unable to find any arterial lesions
+comparable to human arteriosclerosis.
+
+The difficulty experienced by experimenters is not surprising when the
+character of the changes is considered. Arteriosclerosis is not an acute
+process. In its very nature, it is of months' or years' standing, the
+specific changes are of slow growth, and more in the nature of
+degeneration. It would seem that a very careful study of the histories
+of those with arteriosclerosis and a final examination upon the actual
+tissue might eventually give us data for the etiology.
+
+The most frequent site of disease in these experimental lesions is the
+thoracic aorta, and it is there also that the most severe changes are
+seen. While the toxic action is felt in the vessels all over the body,
+the lesions are, as a rule, scattered and small. The thoracic aorta
+stands the brunt of the high pressure, and this combined with the
+poisonous action of the drug or drugs, results in the formation of a
+fusiform aneurysmal dilatation which stops at the diaphragmatic opening.
+The aortic opening in the diaphragm seems to act as a flood gate,
+allowing only a certain amount of blood to flow through, and thus the
+abdominal aorta is protected to a great extent from the deleterious
+effects of increased pressure. Focal degenerative lesions are, however,
+found in the abdominal aorta.
+
+Changes somewhat analogous to those found in the human aorta as the
+result of intimal proliferations, are produced in animals by the toxins
+of the typhoid bacillus and the Streptococcus pyogenes. Clinically,
+Thayer and Brush have found that the arteries of those who have
+recovered from an attack of typhoid fever are more palpable than the
+arteries of average individuals of equal age who have never had the
+disease.
+
+Experimentally, the changes caused by the toxins above noted are
+proliferations of cells in the intima and subintimal tissues, and a
+breaking up of the internal elastic laminæ into several parallel layers
+which stretch themselves among the proliferating cells. The diphtheria
+toxin, on the contrary, produces a lesion more like that caused by
+adrenalin. All pathologists are not agreed as to whether the
+experimental lesions produced by blood pressure raising drugs are
+similar to the arteriosclerotic changes in the arteries of man.
+
+Some of the work on rabbits has been discredited for the reason that
+arteriosclerosis appears spontaneously in about fifteen per cent of all
+laboratory rabbits. Furthermore, comparatively young rabbits have been
+found with arteriosclerosis. O. Loeb, however, denies this. He has
+examined in the course of eight years 483 healthy rabbits and never
+found arterial changes. The spontaneous lesions can not be distinguished
+histologically from those due to adrenalin. They differ macroscopically
+in that the lesion is usually limited to a few foci near the origin of
+the aorta.
+
+Lesions produced by the drugs enumerated above represent one type of
+experimental arteriosclerosis. More interesting and important are the
+experiments which seem to show that high tension alone is capable of
+producing lesions in arteries which in all respects correspond to
+Adami's strain hypertrophy and overstrain theory. It has been shown that
+when a portion of vein is placed under conditions of high arterial
+pressure, as in a transplantation of a portion of vein into a carotid
+artery, the vein undergoes marked connective tissue hypertrophy which
+includes all the coats. This is evidently strain hypertrophy. Again, it
+has been demonstrated that by suspending a previously healthy rabbit by
+the hind legs for three minutes daily over a period of three to four
+months, there results hypertrophy of the heart with thinning and
+dilatation of the arch and the upper part of the thoracic aorta. No
+change was found in the abdominal aorta. The carotids, however, were
+larger than normal and they showed typical intimal sclerosis with
+connective tissue thickening.
+
+Neither I nor others have been able to confirm this experiment, so it is
+very doubtful whether mechanical pressure alone can produce true
+arteriosclerosis. Some evidence is adduced to bear on this point,
+however, in the fact that sclerosis of the pulmonary artery follows
+often upon mitral stenosis. Yet we do not know but that factors other
+than pressure alone produce the arteriosclerotic change in such cases,
+so we are forced back on our conclusion expressed above; viz., that
+experiments on animals fail to sustain the purely mechanical origin of
+arteriosclerosis.
+
+The changes in the intima constitute the effort on the part of nature to
+repair a defect in the vessel wall which is to compensate for the
+weakened media and the widened lumen. This applies only to true
+arteriosclerosis, not to the condition produced experimentally by the
+toxin of the typhoid bacillus, for example.
+
+When an artery loses its elasticity and begins to have connective tissue
+deposited in its walls, the pressure of the blood stretches the vessel
+which is now no longer capable of retracting when the pulse wave has
+passed, and, in consequence, the artery is actually lengthened. This
+necessarily causes a tortuosity of the vessel which can be easily seen
+in such arteries as the temporals, brachials, radials, and other
+arteries near the surface of the skin.
+
+The exact mechanism of increase of blood pressure is not satisfactorily
+explained. The smaller arteries all over the body are supplied with
+vasoconstrictor and vasodilator nerve fibers from the sympathetic
+nervous system. Normally when an organ is actively functionating the
+vessels are widely dilated and the flow of blood is rapid. Among the
+many factors which influence blood pressure and blood supply must be
+reckoned the psychic.
+
+We know that normally there is a certain resistance offered to the
+propulsion of blood through the arteries by the contraction of the
+heart. This tonus is essential to the maintenance of an equalized
+circulation. The muscular arterioles throughout the body by their tonus
+serve to keep up the normal blood pressure and to distribute the blood
+evenly to the various organs. Contraction of a large area of arterioles
+increases the blood pressure and, strangely enough, the arteries respond
+to increased arterial pressure, not by dilatation, but by contraction.
+It would appear that rise of blood pressure tends to throw increased
+work upon the musculature of the arterioles. This may be sufficient only
+to cause them to hypertrophy, but further strain may easily lead to
+exhaustion and to dilatation. "As a result strain hypertrophy of the
+intima shows itself with thickening, and it may also be of the
+adventitia, resulting in chronic periarteritis. And now with continued
+degeneration of the medial muscle in those muscular arteries, fibrosis
+of the media may also show itself. I would thus regard muscular
+hypertrophy of the arteries and fibrosis of the different coats as
+different stages in one and the same process. Whether these peripheral
+changes are the more marked, or the central, depends upon the relative
+resisting power of the elastic and muscular arteries of the individual
+respectively." (Adami.)
+
+[Illustration: Fig. 10.--Cross-section of a small artery in the
+mesentery. Note that the vessel appears capable of being much widened.
+The internal elastic lamina is thrown into folds somewhat resembling the
+convolutions of the brain. Note also that the middle coat of the artery
+is composed almost entirely of muscle. The enormous number of such
+vessels in the mesentery and intestines explains the ability of the
+splanchnic area to accommodate the greater part of the blood in the
+body. Universal constriction of these vessels would naturally render the
+intestines anemic. The vasomotor control of these vessels plays an
+important rôle in the distribution of the blood. Small arteries in the
+skin and in other organs, possibly the brain, have a similar function.
+(Microphotograph, highly magnified.)]
+
+It is conceivable that in one section of the body the vessels may be
+markedly contracted, but if there is dilatation in some other part there
+will be no increased work on the part of the heart, and theoretically,
+there should be no rise of blood pressure. The vascular system, however,
+while likened to a system of rubber tubes, must be regarded as a very
+live system, every subsystem having the property of separate control.
+
+For blood tension to be raised all over the body, conditions must favor
+the generalized contraction of a large area of arterioles. Some authors
+consider that the so-called viscosity of the blood also is a factor in
+the causation of increased tension. The usual cause for the high tension
+is probably the presence in the blood of some poisonous substance.
+
+It is held by some authors that the great splanchnic area is capable of
+holding all the blood in the body and in respect of its liability to
+arteriosclerosis, it is second only to the aorta and coronary arteries.
+The enormous area of the skin vessels could probably contain most of the
+blood. The tone of the vasoconstrictor center controls the distribution
+of blood throughout the body. The fact that the vessels in the
+splanchnic area are frequently attacked by sclerotic changes means, as a
+rule, increase of work for the heart.[1] The resistance offered to the
+passage of the blood must be great and signifies that, for blood to
+travel at the same rate that it did before the resistance set in, more
+power must be expended in its propulsion. In other words, the heart must
+gradually become accustomed to the changed conditions, and, as a result
+of increased work, the muscle hypertrophies. (See Fig. 11.)
+
+ [1] Longcope and McClintock, however, conclude that permanent
+ constriction of the superior mesenteric artery and celiac axis, as well
+ as gradual occlusion of one or both of these vessels, may be present in
+ dogs for at least five months without giving rise to definite and
+ constant elevation of blood pressure or to hypertrophy of the heart.
+ Further, they have been unable to find at autopsy on man a definite
+ association between sclerosis of the abdominal aorta and great
+ splanchnic vessels and cardiac hypertrophy.
+
+[Illustration: Fig. 11.--Enormous hypertrophy of left ventricle probably
+due to prolonged increased peripheral resistance. Note that the whole
+anterior surface of the heart is occupied by the left ventricle. The
+right ventricle does not appear to be much affected. x2/3.]
+
+In diffuse arteriosclerosis accompanied by chronic nephritis the heart
+is always hypertrophied. This is a result, not a cause of the
+condition. In the pure type, there is hypertrophy only of the left
+ventricle without dilatation of the chamber. The muscle fibers are
+increased in number and in size, and there are frequently areas of
+fibrous myocarditis due to necrosis caused by insufficient nutrition of
+parts of the muscle. In these cases the coronary arteries share in the
+generalized arteriosclerotic process. The openings of the arteries
+behind the semilunar valves may be very small. There is often thickening
+and puckering of the aortic valves and of the anterior leaflet of the
+mitral valve leading, at times, to actual insufficiency of the orifice.
+Later, when the heart begins to weaken, there is dilatation of the
+chambers and loud murmurs result, caused by the inability of the
+nondistensible valves to close the dilated orifices. Until the
+compensation is established, it is impossible to say whether or not true
+insufficiency is present.
+
+In senile arteriosclerosis there is the physiologic atrophy of the media
+to be reckoned with. This change has already been referred to. When such
+degeneration has taken place, the normal blood pressure may be
+sufficient to cause stretching of the already weakened media with or
+without hypertrophy of the intima. The arteries may be so lined with
+deposits of calcareous matter that they appear as pipe stems. More
+frequently there are rings of calcified material placed closely together
+or irregular beading, giving to the palpating finger the impression of
+feeling a string of very fine beads. The arteries are often tortuous,
+hard, and are absolutely nondistensible. At times no pulse wave can be
+felt.
+
+The larger arteries such as the brachials and femorals are most
+affected. The walls become thinned and show cracks, and areas
+apparently, but not actually denuded of intima. Yellowish-white,
+irregular, raised plaques are scattered here and there. Interspersed
+among these areas are irregularly shaped clean-cut ulcers having as a
+rule a smooth base, and frequently on the base is a thin plate of
+calcified matter. The color of these denuded areas is usually brownish
+red or reddish brown. White thrombi may be deposited on these areas. The
+danger of an embolus plugging one of the smaller arteries is great and
+probably happens more often than we think. The collateral circulation is
+able to supply the thrombosed area. Should the thrombus be on the
+carotid arteries, hemiplegia may result from cerebral embolism. On
+microscopic examination of the arteries there is seen extreme
+degeneration of all the coats, the degeneration of the media leading
+almost to an obliteration of that coat. On seeing such arteries as these
+one wonders how the circulation could have been maintained and the
+organs nourished. Senile atrophy of the internal organs naturally goes
+hand in hand with such arterial changes.
+
+There is, as a rule, no increase in arterial tension; on the contrary,
+the pressure is apt to be low. This is readily understood when the heart
+is seen. This organ is small, the muscle is much thinned, it is flabby
+and of a brownish tint, the so-called "brown atrophy." Microscopically,
+there is seen to be much fragmentation of the fibers with a marked
+increase of the brown pigment granules which surround the cell nuclei.
+Cases are seen, however, in which blood pressure increases as the
+patient grows older. The hearts in such cases are more or less
+hypertrophied and show extensive areas of fibroid myocarditis.
+
+From what has been said, it follows that hypertension alone may be the
+cause of arteriosclerosis; that certain poisons in the blood which
+attack the media and cause it to degenerate and weaken cause
+arteriosclerosis without increased blood pressure; that the normal blood
+pressure may be, for the artery which is physiologically weakened in an
+individual over fifty, really hypertension, and arteriosclerosis may
+result. Our observations lead us to believe that the process is at
+bottom one and the same. The different types noted clinically depend
+upon the nature of the etiologic factors and the kind of arterial tissue
+with which the individual is endowed. This view at least brings some
+order out of previous chaos, and corresponds well with our present
+knowledge of the disease.
+
+There are many cases of arteriosclerosis which lead to definite
+interference with the closure of the valves of the heart, particularly
+the aortic and the mitral. It has been said that puckerings of the
+valves frequently occur (Fig. 12). This arteriosclerotic endocarditis at
+times leads to very definite heart lesions, chiefly aortic or mitral
+insufficiency, or both with, at times, murmurs of a stenotic character
+at the base. There is rarely true aortic stenosis, however. The murmur
+is caused by the passage of the blood over the roughened valves and into
+the dilated aorta. Aortic stenosis is one of the rarest of the valvular
+lesions affecting the valves of the left heart, and should be diagnosed
+only when all factors, including the typical pulse tracings, are taken
+into consideration.
+
+[Illustration: Fig. 12.--Aortic incompetence with hypertrophy and
+dilatation of left ventricle, the result of arteriosclerosis affecting
+the aortic valves. Note how the valves have been curled, thickened, and
+shortened, the edges of valves being a half inch below the upper points
+of attachment. The anterior coronary artery is shown, the lumen
+narrowed. (Reduced one-half.)]
+
+The kidneys, as a rule, show extensive sclerosis. They are small, firm,
+and contracted and not always to be differentiated from the contracted
+kidneys of chronic inflammation. The lesions of the arteriosclerotic
+kidney are due to narrowing and eventual obstruction of the afferent
+vessels. The organs are usually bright red or grayish red in color. At
+times there is marked fatty degeneration of cortex and medulla, giving
+to them a yellowish streaking. The capsule is here and there adherent,
+the cortex is much thinned and irregular. The surface presents a
+roughly granular appearance. The glomeruli stand out as whitish dots
+and the sclerosed arteries are easily recognized, as their walls are
+much thickened. The process does not, as a rule, affect the whole kidney
+equally, but rather affects those portions corresponding to the
+interlobular arteries. The replacement of the normal kidney tissue by
+connective tissue and the resulting contraction of this latter tissue
+leads to the formation of scars. As the process is not regular, the
+scarring is deeper in some places than in others, with the result that
+localized rather sharply depressed areas appear on the surface. The
+pelvis is relatively large and is filled with fat. The renal artery is
+often markedly sclerosed and the whole process may be due to localized
+thickening of the artery, or as part of a general arteriosclerosis. The
+latter is the more frequent. Microscopically, it is seen that the
+tubules are atrophied, the Bowman's capsules are, as a rule, thickened,
+and the glomeruli are shrunken or have been replaced by fibrous tissue.
+In places they have fallen out of the section. There is marked
+proliferation of connective tissue in cortex and medulla. The arterioles
+are thickened, the sclerosis being either of the intima or media or of
+both. There is even occlusion of many arterioles.
+
+Changes in other organs as the result of arteriosclerosis of their
+afferent vessels occur, but are not so characteristic as in the kidney.
+In the brain the result of gradual thickening of the arterioles is a
+diminished blood supply, softening of the portion supplied by the
+artery, and later a connective tissue deposit. The occurrence of thrombi
+is favored and, now and again, a thrombus plugs an artery which supplies
+an important and even vital part of the brain. The arteries of the brain
+are end arteries, hence there is no chance for collateral circulation.
+It is therefore evident how serious a result may follow the disturbance
+in or actual deprivation of blood supply to any of the brain centers or
+to the internal capsule.
+
+
+=Arteriosclerosis of the Pulmonary Arteries=
+
+There have been a number of cases of sclerosis of the pulmonary
+arteries, either alone, or associated with general systemic
+arteriosclerosis.
+
+A primary and a secondary form are recognized, the former in conjunction
+with congenital malformations of the heart, the latter as the result of
+severe infection or of mitral stenosis. These two causes seem to be the
+most important in the production of the arterial changes. The cases thus
+far described have revealed widespread thickening of the pulmonary
+arteries. If one may judge by the description of the pathologic changes,
+the condition is quite similar to that produced in a vein by
+transplantation along the course of an artery. The diffuse form with
+connective tissue thickening of all coats has been generally described.
+There is also obliterating endarteritis of the smaller vessels. In the
+etiology of the condition severe infection seems to play a prominent
+rôle. The constant presence of right ventricular hypertrophy is
+interesting, the heart dullness extends, as a rule, far to the right of
+the sternum. In some of the cases no demonstrable changes were observed
+in the bronchial arteries or in the pulmonary veins.
+
+Sanders has described a case of primary pulmonary arteriosclerosis with
+hypertrophy of the right ventricle.
+
+Recently Warthin[2] has reported a case of syphilitic sclerosis of the
+pulmonary artery which places the lesion in exactly the same category as
+that of syphilis in the systemic arteries. There was also aneurysm of
+the left upper division present and, to settle the etiologic nature of
+the process, Spirochete pallida were found in the wall of the aneurysm
+sac and in that of the pulmonary artery. The microscopic picture in the
+pulmonary artery could not be told from that in a syphilitic aorta.
+
+ [2] Warthin, A. S.: Am. Jour. Syph., 1918, i, 693.
+
+
+=Sclerosis of the Veins=
+
+Phlebosclerosis not infrequently occurs with arteriosclerosis. It is
+seen in those cases characterized by high blood pressure. Such increased
+pressure in the veins is due, for example, to cirrhosis of the liver
+which affects the portal circulation, or to mitral stenosis which
+affects the pulmonary veins. The affected vessels are usually dilated.
+The intima shows compensatory thickening especially where the media is
+thinned. As a rule all the coats are involved in the connective tissue
+thickening. Occasionally hyaline degeneration or calcification of the
+new-formed tissue is seen. "Without existing arteriosclerosis the
+peripheral veins may be sclerotic usually in conditions of debility, but
+not infrequently in young persons." (Osler.)
+
+In many cases of arteriosclerosis, the pathologic changes are not
+confined to the arteries, but are found in the veins as well as in the
+capillaries. Such cases could be called angiosclerosis.
+
+
+
+
+CHAPTER III
+
+PHYSIOLOGY OF THE CIRCULATION
+
+
+No attempt will be made to cover the entire subject of the physiology of
+the circulation. Only in so far as it relates to arteriosclerosis and
+blood pressure and has a bearing on the probable explanation of blood
+pressure phenomena will it be discussed.
+
+"The heart and the blood vessels form a closed vascular system,
+containing a certain amount of blood. This blood is kept in endless
+circulation mainly by the force of the muscular contractions of the
+heart; but the bed through which it flows varies greatly in width at
+different parts of the circuit, and the resistance offered to the moving
+blood is very much greater in the capillaries than in the large vessels.
+It follows, from the irregularities in size of the channels through
+which it flows, that the blood stream is not uniform in character
+throughout the entire circuit--indeed, just the opposite is true. From
+point to point in the branching system of vessels the blood varies in
+regard to its velocity, its head of pressure, etc. These variations are
+connected in part with the fixed structure of the system and in part are
+dependent upon the changing properties of the living matter of which the
+system is composed." (W. H. Howell.)
+
+If the vascular system were composed of a central pump, projecting at
+every stroke a given amount of liquid into a series of rigid tubes, the
+aggregate cross sections of which were equal to the cross section of the
+main pipe, then the velocity at the openings would be the same as at the
+source (making allowances for friction). The problem would then be a
+simple one. In the circulation of the blood no such simple condition
+obtains. The capillary beds is an enormous area through which the blood
+flows slowly. From the time the blood is thrown into the aorta the
+velocity begins to diminish until it reaches its minimum in the
+capillaries. In no two persons is the initial velocity at the heart the
+same, nor in the same person is it the same at all times of day. The
+size of the heart, the actual strength of the muscle, the amount of
+blood ejected at every beat, and the size and elasticity of the aorta
+are some of the factors which determine the velocity of blood at the
+aortic orifice. When to these factors are added the differences in
+arterial tissue, the activity or resting stage of the various organs,
+etc., the question becomes exceedingly complicated. In spite of these
+many disturbing elements, attempts more or less successful have been
+made to estimate the velocity of the blood in animals. Thus, in the
+carotid of the horse the velocity was found to be 300 mm. per second
+(Volkman) and 297 mm. (Chauveau); in the carotid of the dog, 260 mm.
+(Vierordt). In the jugular vein of the dog Vierordt found the velocity
+to be 225 mm. per second. These figures do not represent the actual
+velocity of the blood in all horses or all dogs, but they do give us
+some general idea of the rate of flow of the blood. For man it has been
+calculated that the velocity in the aorta is about 320 mm. per second.
+The velocity is not uniform in the large arteries, where at every heart
+beat there is a sudden increase followed by a decrease as the heart goes
+into diastole. The farther away from the heart the measurements are made
+the more even is the flow.
+
+Observations by W. H. Luedde with the Zeiss binocular corneal microscope
+on the rate of flow in the conjunctival capillaries must modify somewhat
+our former conceptions. He finds that "The rate varies in the different
+arteries, capillaries, and veins from a barely perceptible motion to a
+little more than 1 mm. per second. Further, some parts of the capillary
+network are ordinarily supplied with blood elements only occasionally.
+This is shown by the passage of a column of corpuscles along a certain
+line, followed after an interval of seconds, during which no corpuscles
+pass, by another column in the same line as before."
+
+The vessels of the conjunctiva probably are quite like superficial
+vessels in the skin and mucous membranes. Therefore, we must be free to
+admit that the circulation in them is not absolutely steady. Luedde
+found further that in syphilitics there were tortuosities,
+irregularities, minute aneurysmal dilatations and even obliterations of
+capillaries. Some of the changes occurred as early as one month after
+infection.
+
+The rate in the capillaries of man is estimated to be between 0.5 mm.
+and 0.9 mm. per second. As the blood is collected into the veins and the
+bed becomes smaller, the velocity increases until at the heart it is
+almost the same as in the aorta. That the velocity could not be exactly
+the same is evident from the fact that the cross section of the veins,
+which return the blood to the right auricle, is greater than is the
+cross section of the aorta.
+
+The volume of the bed is subject to rapid and wide fluctuations, which
+are dependent on many causes, both physiologic and pathologic. The call
+of an actively functionating organ or group of organs causes a widening
+of a more or less extensive area, and the velocity necessarily varies.
+In states of great relaxation of the vessels there may be a capillary
+pulse. In order to force blood at the same rate through dilated vessels
+as through normal vessels, there must be more blood or there must be a
+more rapid contraction of the central pump. What actually happens, as a
+rule, is an increase in the rate of the heart beat. There are
+conditions--such, for example, as aortic insufficiency--where actually
+more blood is thrown into the circulation at every beat, so that the
+rate is not changed.
+
+It has been calculated that the average amount of blood thrown into the
+aorta at every systole of the heart is from 50 to 100 c.c. This is
+forcibly ejected into a vessel already filled (apparently) with blood.
+In order to accommodate this sudden accession of fluid, the aorta must
+expand. The aortic valves close, and during diastole the blood is forced
+through the vascular system by the forcible, steady contraction of the
+highly elastic aorta. Other large vessels which branch from the aorta
+also have a part in this steady propulsion of blood. From seventy to
+eighty times a minute the aorta is normally forcibly expanded to
+accommodate the charge of the ventricle. It is not difficult to
+understand the great frequency of patches of sclerosis in the arch when
+these facts are borne in mind.
+
+What relationship the viscosity of the blood has to the rate and volume
+of flow is not fully understood. As yet there is not much known about
+the subject, and no one has devised a satisfactory means of measuring
+the viscosity. It is thought by some that an increased viscosity assists
+in producing an increased amount of work for the heart.
+
+
+=Blood Pressure=
+
+Blood pressure is the expression used for a series of phenomena
+resulting from the action of the heart. As every heart beat is actual
+work done by the heart in overcoming resistance to the outflow of blood,
+this force is approximately measurable in a large artery such as the
+brachial. It has been determined that the pressure in the brachial
+artery is almost equal to the intraventricular pressure in the left
+ventricle. In animals it is easy to attach manometers to the carotid
+artery and to measure the blood pressure accurately. Formerly the method
+consisted in attaching a tube and allowing the blood to rise in the
+tube. The height to which the blood rose measured the maximum pressure.
+This is a crude method and has been replaced by the U-tube of mercury
+with connection made to the artery by saline or Ringer's solution. This
+apparatus is familiar to all physiologists.
+
+In man the measurement is most conveniently made from the brachial
+artery. There is some difference in the pressure in the femoral and the
+brachial and some use both arteries. However, the difficulty of
+adjusting instruments to the upper leg, the great force which must be
+used to compress the femoral artery and the relative inaccessibility of
+the leg as compared to the arm, make the leg an inconvenient part for
+use in blood pressure determinations. It is not to be recommended.
+
+Blood pressure is a valuable aid in diagnosis and of material help in
+many cases in prognosis, but it is not infallible neither can it be used
+alone to diagnose a case. Blood pressure is only one of many links in a
+chain of evidence leading to diagnosis. It has been badly used and much
+abused. It has been condemned unjustly when it did not furnish _all_ the
+evidence. It has been made a fetish and worshipped by both doctors and
+patients. A sane conception of blood pressure must be widely
+disseminated lest we find it being discarded altogether.
+
+Blood pressure consists of more than the estimation of the systolic
+pressure. The blood pressure picture consists of (1) the systolic
+pressure, (2) the diastolic pressure, (3) the pulse pressure which is
+the difference between the systolic and diastolic pressure, (4) the
+pulse rate. Expressed in the literature it should read thus: 120-80-40;
+72. That tells the whole story in a brief, accurate form. This is
+recommended in history reporting. It must be ever kept in mind that a
+blood pressure reading represents the work of the heart at the _moment
+when it was taken_. Within a few minutes the pressure may vary up or
+down. There is no normal pressure as such, but an average pressure for
+any group of people of the same age living under similar conditions. The
+habit of speaking of any systolic figure as normal should be broken. A
+pressure picture may be normal but a systolic reading, whatever it may
+be, is not accurately designated as normal. This distinction is worth
+insisting upon.
+
+
+=Blood Pressure Instruments=
+
+There are several instruments which are in common use for the purpose of
+recording blood pressure in man.
+
+Historically, the determination of blood pressure for man began with the
+attempt of K. Vierordt in 1855 to measure the blood pressure by placing
+weights on the radial pulse until this was obliterated. The first useful
+instrument, however, was devised by Marcy in 1876. He placed the hand in
+a closed vessel containing water connected by tubing with a bottle for
+raising the pressure and by another tube with a tambour and lever for
+recording the size of the pulse waves. He maintained that when pressure
+on the hand was made, the point where oscillations of the lever ceased
+was the maximal pressure, the point where the oscillations of the
+recording lever was largest, was the minimal pressure.
+
+This pioneer work was practically forgotten for twenty-five years. It
+was not until 1887 that V. Basch devised an instrument which was used to
+some extent. This instrument recorded only maximum pressure. It
+consisted of a small rubber bulb filled with water communicating with a
+mercury manometer. The bulb was pressed on the radial artery until the
+pulse below it was obliterated and the pressure then read off on the
+column of mercury. V. Basch later substituted a spring manometer for the
+mercury column. Potain modified the apparatus by using air in the bulb
+with an aneroid barometer for recording the pressure. These instruments
+are necessarily grossly inaccurate. Moreover, they do not record the
+diastolic pressure.
+
+In 1896 and 1897 further attempts were made to record blood pressure by
+the introduction of a flat rubber bag encased in some nonyielding
+material, which was placed around the upper arm. Riva-Rocci used silk,
+while Hill and Barnard used leather. The latter used a bulb or Davidson
+syringe to force air into the cuff around the arm and palpated the
+radial artery at the wrist, noting the point of return of the pulse
+after compression of the upper arm, and reading the pressure on a column
+of mercury in a tube.
+
+Except that the width of the cuff has been increased from 5 cm. to 12
+cm., this is the general principle upon which all the blood pressure
+instruments now in use are based. Most of the apparatuses make use of a
+column of mercury in a U-tube to record the millimeters of pressure. As
+the mercury is depressed in one arm to the same extent as it is raised
+in the other arm the scale where readings are made is .5 cm. and the
+divisions represent 2 mm. of mercury but are actually 1 mm. apart.
+
+The cuff was made 12 cm. in diameter because it was shown (v.
+Recklinghausen) that with narrow cuffs much pressure was dissipated in
+squeezing the tissues. Janeway has shown that with the use of the 12 cm.
+cuff accurate values are obtained independently of the amount of muscle
+and fat around the brachial artery. In other words if an actual systolic
+blood pressure of 140 mm. is present in two individuals, the one with a
+thin arm, the other with a thick arm, the instrument will record these
+pressures the same where a 12 cm. arm band is used. We need have no fear
+of obtaining too high a reading when we are taking pressure in a stout
+or very muscular individual. Janeway also was the first to call
+attention to the fact that the diastolic or minimal pressure was at the
+point where the greatest oscillation of the mercury took place. This is
+difficult to estimate in many cases as the eye can not follow slight
+changes in the oscillation when the pressure in the cuff is gradually
+reduced. Practically this is the case in small pulses.
+
+The Riva-Rocci instrument was modified by Cook. (See Fig. 13.) He used a
+glass bulb containing mercury into which a glass tube projected. The
+bulb was connected by outlet and tubing to the cuff and syringe. The
+glass tube was marked off in centimeters and millimeters and for
+convenience was jointed half way in its length. The instrument could be
+carried in a box of convenient size. This instrument is fragile and more
+cumbersome, although lighter in weight, than others and is very little
+used at present.
+
+[Illustration: Fig. 13.--Cook's modification of Riva-Rocci's blood
+pressure instrument.]
+
+Stanton's instrument (Fig. 14) is practically Cook's made more rigid in
+every way but without the jointed tube. The cuff has a leather casing,
+the pressure bulb is of heavy rubber, the glass tube in which the
+mercury rises is fixed against a piece of flat metal and there are
+stopcocks in a metal chamber introduced between the bulb and mercury
+with which to regulate the in- and out-flow of air. The pressure can be
+gradually lowered conveniently without removing the pressure bulb.
+
+[Illustration: Fig. 14.--Stanton's sphygmomanometer.]
+
+The most accurate mercury manometer is that of Erlanger. (Fig. 15.) The
+instrument is bulky and is not practicable for the physician in
+practice. The principle is that used by Riva-Rocci. There is an extra
+T-tube introduced between the manometer and air bulb connecting with a
+rubber bulb in a glass chamber. The oscillations of this are
+communicated to a Marey tambour and recorded on smoked paper revolving
+on a drum. There is a complicated valve which enables the operator to
+reduce the pressure with varying degrees of slowness. The mercury is
+placed in a U-tube with a scale alongside it. The instrument is
+expensive and not as easy to manipulate as its advocates would have us
+believe. Hirschfelder has added to the usefulness (as well as to the
+complexity) of the Erlanger instrument, by placing two recording
+tambours for the simultaneous registering of the carotid and venous
+pulses. In spite of its complexity and necessary bulkiness, very
+valuable data are obtained concerning the auricular contractions.
+
+[Illustration: Fig. 15.--The Erlanger sphygmomanometer with the
+Hirschfelder attachments by means of which simultaneous tracings can be
+obtained from the brachial, carotid, and venous pulses.]
+
+One of the best of the mercury instruments is the Brown
+sphygmomanometer. In this (Fig. 16) the mercury is in a closed,
+all-glass tube so that it can not spill under any sort of manipulation.
+It is in this sense "fool-proof." The cuff, however, is poorly
+constructed. It is too short and there are strings to tie it around the
+arm. I have found that this causes undue pressure in a narrow circle and
+renders the reading inaccurate. In the clinic we use this mercury
+instrument with a long cuff like that provided by the Tycos instrument.
+
+[Illustration: Fig. 16.--Desk model Baumanometer.]
+
+The Faught instrument (Fig. 17) is larger than the Brown, but is less
+easily broken and is not too cumbersome to carry around. The
+substitution of a metal air pump for the rubber makes the apparatus more
+durable.
+
+[Illustration: Fig. 17.--The Faught blood pressure instrument. An
+excellent instrument which is quite easily carried about and is not
+easily broken.]
+
+The v. Recklinghausen instrument is not employed to any extent in this
+country. It is both expensive and cumbersome, and has no advantages over
+the other instruments.
+
+Several other instruments have been devised and new ones are constantly
+being added to the already large list. With those employing mercury the
+principle is the same. The aim is to make an instrument which is easily
+carried, durable, and accurate.
+
+In all the mercury instruments the diameter of the tube is 2 mm. One
+would suppose that there would be noticeable differences in the readings
+of the different mercury instruments depending upon the amount of
+mercury used in the tube. By actual weight there is from 35 to 45 gms.
+of mercury in the several instruments. After many trials, no noticeable
+differences in blood pressure readings can be made out between a column
+weighing 35 gm. and one weighing 45 gm.
+
+There is, however, the inertia of the mercury to be overcome, friction
+between the tube and the mercury, and vapor tension. The mercury is
+therefore not as sensitive to rapid changes of pressure in the cuff as a
+lighter fluid would be. The mercury must be clean and the tube dry so
+that there is no more friction than what is inherent between the mercury
+and glass. In making readings on a rapid pulse the oscillations of the
+mercury column are apt to be irregular or to cease now and then, due to
+the fact that the downward oscillation coincides with a pulse wave, or
+an upward oscillation receives the impact of two pulse waves transmitted
+through the cuff. Instruments have been devised to obviate this
+difficulty, but they have not come into favor. They are usually too
+complicated and at present can not be recommended.
+
+[Illustration: Fig. 18.--Rogers' "Tycos" dial sphygmomanometer.]
+
+An instrument devised by Dr. Rogers (the "Tycos") has met with
+considerable popularity. (Fig. 18.) This is not an instrument which
+operates with a spring and lever. The instrument is composed essentially
+of two metal discs carefully ground and attached at their circumferences
+to the metal casing below the dial. There is an air chamber between
+these discs through the center of which air is forced by the syringe
+bulb. When air is forced into the space between these two discs, they
+are forced apart to a very slight extent, with the highest pressures
+only 2-3 mm. of bulging occurs. From data gathered after extensive use
+for five years these discs were not found to have sprung. A lever
+attached to a cog which in turn is attached to the dial needle magnifies
+to an enormous extent the slightest expansion of the discs. Every dial
+is handmade and every division is actually determined by using a U. S.
+government mercury manometer of standard type. No two dials therefore
+are alike in the spacing of the divisions of the scale but every one is
+calibrated as an individual instrument. There is no doubt in the
+author's mind that for the general practitioner the instrument has some
+advantages over the mercury instruments. It reveals the slightest
+irregularity in force of the heart beat. The oscillation of the dial
+needle is more accurately followed by the eye than is that of the column
+of mercury. The needle passes directly over the divisions of the scale,
+while with usual mercury instruments the scale is an appreciable
+distance (sometimes .5 cm.) from the column of mercury at the side.
+(Fig. 19.) The diastolic pressure is more easily read on the "Tycos."
+It is where the maximum oscillation of the needle occurs as the pressure
+is slowly released from the cuff. Although it does not appear that this
+instrument, if properly made and standardized, could become inaccurate,
+nevertheless it is advisable to check it every few months against a
+known accurate mercury manometer instrument.
+
+[Illustration: Fig. 19.--Detail of the dial in the "Tycos" instrument.]
+
+[Illustration: Fig. 20.--Faught dial instrument.]
+
+[Illustration: Fig. 21.--Detail of the dial of the Faught instrument.]
+
+Another perfectly satisfactory dial instrument is the Faught (Figs. 20
+and 21). The general plan of this differs in some minor points from the
+"Tycos." I have compared the two and have found no difference in the
+readings. Both can be recommended.
+
+[Illustration: Fig. 22.--The Sanborn instrument.]
+
+One or two other cheaper dial instruments are on the market. The Sanborn
+seems to be quite satisfactory. (Fig. 22.) It is cheaper than the other
+dial instruments. There is this much to be said, no instrument using a
+spring as resistance to measure pressure can be recommended.
+
+
+=Technic=
+
+The same technic applies to all the mercury instruments. The patient
+sits or lies down comfortably. The right or left arm is bared to the
+shoulder, the cuff is then slipped over the hand to the upper arm. (See
+Fig. 23.) At least an inch of bare arm should show between the lower end
+of the cuff and the bend of the elbow. The rubber is adjusted so that
+the actual pressure from the bag is against the inner side of the arm.
+The straps are tightened, care being taken not to compress the veins.
+The upper part of the cuff should fit more snugly than the lower part.
+The part of the instrument carrying the mercury column is now placed on
+a level surface; the two arms of the mercury in the tube must be even,
+and at _0_ on the scale. With the fingers of one hand on the radial
+pulse, the bag is compressed until the pulse is no longer felt. (See
+Fig. 24.) One should raise the pressure from 10-12 mm. above this, and
+close the stopcock between the bulb and the mercury tube. In a good
+instrument the column should not fall. If it does there is a leak of air
+in the system of tubing and arm bag. Now with the finger on the pulse,
+or where the pulse was last felt, gradually allow air to escape by
+turning the stopcock so that the column of mercury falls about 2 mm.
+(one division on the scale) for every heart beat or two. One must not
+allow the column of mercury to descend too slowly as it is
+uncomfortable for the patient and introduces a psychic element of
+annoyance which affects the blood pressure. On the other hand, the
+pressure must not be released too rapidly, else one runs over the points
+of systolic and diastolic pressure and the readings are grossly
+inaccurate. It is impossible to say how rapidly the mercury must fall.
+Every operator must find that out for himself by practice. The first
+perceptible pulse wave felt beneath the palpating finger at the wrist,
+represents on the scale the systolic pressure. This can be seen to
+correspond to a sudden increase in the magnitude of the oscillation of
+the mercury column. The systolic pressure, thus obtained, is from 5-10
+mm. lower than the real systolic pressure. The more sensitive the
+palpating finger, the more nearly does the systolic pressure reading
+approach that found by using such an instrument as Erlanger's, where the
+first pulse wave is magnified by the lever of the tambour.
+
+[Illustration: Fig. 23.--Method of taking blood pressure with a patient
+in sitting position.]
+
+[Illustration: Fig. 24.--Method of taking blood pressure with patient
+lying down.]
+
+The pressure is now allowed to fall, until the palpating finger feels
+the largest possible pulse wave, which is coincident with the greatest
+oscillation of the mercury. This is the diastolic pressure. Beyond this
+point there is no oscillation of the mercury column. The difference
+between the two is the pulse pressure. Thus the pulse is felt after
+compression at 120 on the scale, and the maximum oscillation occurs at
+80. The systolic pressure is 120 mm., the diastolic is 80 mm., and the
+pulse pressure is 40 mm.
+
+With the "Tycos" or Faught the arm band is snugly wound around the arm,
+the bag next to the skin and the end tucked in, so that the whole band
+will not loosen when air is forced into the bag. The cuff is blown up
+until the pulse is no longer felt. One should raise the pressure not
+more than 10 mm. above the point of obliteration of the pulse. The valve
+is then carefully opened so that the needle gradually turns toward zero.
+At the first return of the pulse wave felt at the wrist, the needle is
+sure to give a sudden jump. This is the systolic pressure and is read
+off on the scale. The needle is now carefully watched until it shows the
+maximum oscillation. This is the diastolic pressure. The difference
+between the two is, as above, the pulse pressure.
+
+In taking pressure one should take the average of several, three or
+four. Moreover, one must not take consecutive readings too quickly and
+one must be sure that between every two readings all the air is out of
+the cuff and that the mercury or dial is at zero. _It has been
+repeatedly shown that in a cyanosed arm the systolic pressure is raised
+so that even slight cyanosis between readings must be carefully
+avoided._
+
+The only accurate method of determining both the systolic and diastolic
+pressure, but especially the diastolic, is by the so-called auscultatory
+method. (See Fig. 25.) The cuff is adjusted in the usual way and one
+places the bell of a binaural stethoscope over the brachial artery from
+one to two centimeters below the lower edge of the cuff.[3] Care must
+be taken that the bell is not pressed too firmly against the arm and
+that the edge of the bell nearest the cuff is not pressed more firmly
+than the opposite end. For this purpose, one can not use the ordinary
+Bowles stethoscope or any of the other much lauded stethoscopes, because
+the surface of the bell is too large. The diameter of the bell must not
+be more than twenty-five millimeters, twenty is still better. It is
+advisable before beginning the observation to locate with the finger the
+pulse in the brachial artery just above the elbow, so that the
+stethoscope may be placed over the course of the artery. (Fig. 26.) The
+first wave which comes through is heard as a click, and occurs at a
+point on the manometer or dial scale from 5-10 mm. higher than can
+usually be palpated at the radial artery. This is the true systolic
+pressure. By keeping the bell of the stethoscope over the brachial
+artery while the pressure is falling, one comes to a point when all
+sound suddenly ceases. This is said to be the diastolic pressure. This
+is incorrect as will be shown later.
+
+ [3] A firm makes a stethoscope so that the bell is clamped on the arm
+ leaving both the operator's hands free.
+
+[Illustration: Fig. 25.--Observation by the auscultatory method and a
+mercury instrument. One hand regulates the stop cock which releases air
+gradually.]
+
+[Illustration: Fig. 26.--Observation by the auscultatory method and a
+dial instrument. The right hand holds the bulb and regulates the air
+valve.]
+
+
+=Arterial Pressure=
+
+The arterial pressure in the large arteries undergoes extensive
+fluctuations with every heart beat. The maximum pressure produced by the
+systole of the left ventricle of the heart is known as the =maximum= or
+=systolic pressure=. It practically equals the intraventricular
+pressure. The minimum pressure in the artery, the pressure at the end of
+diastole, is called the =diastolic pressure=. The difference between the
+systolic and diastolic pressures is known as the =pulse pressure=. There
+is yet another term known as the =mean pressure=. For convenience, this
+may be said to be the arithmetical mean of the systolic and diastolic
+pressures. Actually, however, this can not be the case, owing to the
+form of the pulse wave, which is not a uniform rise and fall--the
+upstroke being a straight line, but the downstroke being broken usually
+by two notches. We do not make use of the mean pressure in recording
+results. It is of experimental interest and needs only to be mentioned
+here.
+
+[Illustration: Fig. 27.--Schema to illustrate the gradual decrease in
+pressure from the heart to the vena cava: (a), arteries; (c),
+capillaries; (v), veins; (A), aorta, pressure 150 mm.; (B), brachial
+artery, pressure 130 mm.; (F), femoral vein, 20 mm.; (IVC), inferior
+vena cava, 3 mm. (Modified from Howell.)]
+
+It has been shown that the mean pressure is quite constant throughout
+the whole arterial system. The maximum pressure necessarily falls as the
+periphery of the vascular system is approached. In general it may be
+said that the minimal pressure is quite constant. Too little attention
+is paid to minimal and pulse pressure. The minimal pressure is
+important, for it gives us valuable data as to the actual propulsive
+force driving the blood forward to the periphery at the end of diastole.
+
+It is readily understood how the maximum pressure falls as the periphery
+is approached, until in the arterioles the maximum and minimum pressures
+are about equal. The pressure then in these arterioles is practically
+the same as the diastolic pressure. Actually it is a few millimeters
+less. The diastolic blood pressure would, therefore, measure the
+peripheral resistance and, as the maximum for systolic pressure
+represents approximately the intraventricular pressure, the difference
+between the two, the pulse pressure, actually represents the force which
+is driving the blood onward from the heart to the periphery. It is hence
+very evident that the mere estimation of the systolic pressure gives us
+but a portion of the information we are seeking.
+
+The pulse pressure is subject to wide fluctuations but as a rule for any
+one normal heart it remains fairly constant as the rate varies. In a
+rapidly beating heart the diastole is short and the diastolic pressure
+rises. If the systolic pressure does not also rise, as in a normal heart
+following exercise, we will say, the pulse pressure falls. We know that
+when the pulse rate is constant, vasodilatation causes a fall in
+diastolic pressure and a rise in pulse pressure. On the contrary,
+vasoconstriction causes a rise in diastolic pressure and a fall in pulse
+pressure.
+
+It is very probably the case that with two individuals of equal age and
+equal pulse rate, and equal systolic pressure of 160 mm., the one with a
+diastolic pressure of 110 mm. and, therefore, a pulse pressure of 50 mm.
+is much worse off than the other with a diastolic pressure of 90 mm. and
+a pulse pressure of 70 mm. The latter may be normal for the age of the
+person especially when certain forms of fibrous arteriosclerosis
+accompanied by enlarged heart are present.
+
+The former is not normal for any age. Low pulse pressure usually means a
+weak vasomotor control and is only found in failing circulation or in
+markedly run down states, such as after serious illness or in
+tuberculosis. Therefore, it is most important to estimate accurately the
+diastolic pressure as well as the systolic pressure, for only in this
+way can we obtain any data of value regarding the driving power of the
+heart and the condition of the vasomotor system. A high systolic
+pressure does not necessarily mean that a great deal of blood is forced
+into the capillaries. Actually it may mean that very little blood enters
+the periphery. The heart wastes its strength in dilating constricted
+vessels without actually carrying on the circulation adequately.
+
+
+=Normal Pressure Variations=
+
+The systolic pressure varies considerably under conditions which are by
+no means abnormal. Thus, the average for men at all ages is about 127
+mm. Hg. (All measurements are taken from the brachial artery, with the
+individuals in the sitting posture.) For women the average is somewhat
+lower, 120 mm. Hg. The pressure is lowest in children. In children from
+6-12 years the average systolic pressure is 112 mm. Normally, there is a
+gradual increase as age comes on, due, as will be shown in the
+succeeding chapter, to physiologic changes which take place in the
+arteries from birth to old age. In the chart here appended is
+graphically shown the normal variations in the blood pressure at
+different ages compiled from observations made on one thousand
+presumably normal persons. (Fig. 28.)
+
+[Illustration: Fig. 28.--Chart showing the normal limits of variation in
+systolic blood pressure. (After Woley.)]
+
+The diastolic pressure has been estimated to be about 35 to 45 mm. Hg
+lower than the systolic pressure, and consequently these figures
+represent the pulse pressure in the brachial artery of man. This is
+equivalent to saying that every systole of the left ventricle distends
+this artery by a sudden increase in pressure equal to the weight of a
+column of mercury 2 mm. in diameter and 35 to 45 mm. high. Naturally, at
+the heart the pressure is highest. As the blood goes toward the
+capillary area the pressure gradually decreases until, at the openings
+of the great veins into the heart, the pressure is least. At the aorta
+(A) the pressure (systolic) is approximately 150 mm. Hg, at the brachial
+artery (B) it is 130 mm., in the capillary system (C) it is 30 mm., in
+the femoral vein (F) it is 20 mm., at the opening of the inferior vena
+cava (I) it is 3 mm.
+
+Attention has been called to the normal systolic pressure at different
+ages. This is not the only cause for variations in the blood pressure.
+Normally, it is greater when in the erect position than when seated,
+and greater when seated than when lying down. During the day there are
+well-recognized changes. The pressure is lowest during the early morning
+hours, when the person is asleep. In women there are variations due to
+menstruation. Muscular exercise raises the blood pressure markedly. The
+effect of a full meal is to raise the blood pressure. The explanation is
+that during and following a meal there is dilatation of the abdominal
+vessels. This takes blood from other parts of the body, provided that
+the other factors in the circulation remain constant. A fall of
+pressure would necessarily occur in the aorta. To compensate for this,
+there is increased work on the part of the heart, which reveals itself
+as increased pressure and pulse pressure. It is well known that the
+interest in the process taken by an individual upon whom the blood
+pressure is estimated for the first time tends to increase the rate of
+the heart and to raise the blood pressure. For this reason the first few
+readings on the instrument must be discarded, and not until the patient
+looks upon the procedure calmly can the true blood pressure be obtained.
+As a corollary to this statement, mental excitement, of whatever kind,
+has a marked influence on the pressure. The patient must remain
+absolutely quiet. Raising the head or the free arm causes the pressure
+to rise. Another important physiologic variation is produced by
+concentrated mental activity. This tends to hurry the heart and increase
+the force of the beat. In short, it may be stated as a general rule that
+any active functioning of a part of the body which naturally requires a
+great excess of blood tends to elevate the blood pressure. At rest the
+pressure is constant. Variations caused by the factors mentioned act
+only transitorily, and the pressure shortly returns to normal.
+
+
+=The Auscultatory Blood Pressure Phenomenon=
+
+Since the first description of the auscultatory blood pressure sounds by
+Korotkov in 1905, this method has been more and more employed until
+today it is the standard, recognized method of determining the points in
+the blood pressure reading. When one applies the 12 cm. arm band over
+the brachial artery and listens with the bell of the stethoscope about
+one cm. below the cuff directly over the brachial artery near the bend
+of the elbow, one hears an interesting series of sounds when the air in
+the cuff is gradually reduced. The cuff is blown up above the maximum
+pressure. As the air pressure around the arm gradually is lowered, the
+series of sounds begins with a rather low-pitched, clear, clicking
+sound. This is the first phase. This only lasts through a few
+millimeters fall when a murmur is added and the tone becomes louder.
+This click and murmur phase is the second phase. A few millimeters more
+of drop in pressure and a clear, sharp, loud tone is audible. Usually
+this tone lasts through a greater drop than any of the other tones. This
+is the third phase. Rather suddenly the loud, clear tone gives place to
+a dull muffled tone. In general the transition is quite sharp and
+distinct. This is the fourth phase. The tone gradually or quickly ceases
+until no tone is heard. This is the fifth phase (Ettinger.)
+
+The first phase is due to the sudden expansion of the collapsed portion
+of the artery below the cuff and to the rapidity of the blood flow. This
+causes the first sharp clicking sound which measures the systolic
+pressure.
+
+The second, or murmur and sound phase, is due to the whorls in the blood
+stream as the pressure is further released and the part of the artery
+below the cuff begins to fill with blood.
+
+The third tone phase is due to the greater expansion of the artery and
+to the lowered velocity in the artery. A loud tone may be produced by a
+stiff artery and a slow stream or by an elastic artery and a rapid
+stream. This tone is clear cut and in general is louder than the first
+phase.
+
+The fourth phase is a transition from the third and becomes duller in
+sound as the artery approaches the normal size.
+
+The fifth phase, no sound phase, occurs when the pressure in the cuff
+exerts no compression on the artery and the vessel is full throughout
+its length.
+
+It is generally conceded that the sounds heard are produced in the
+artery itself and not at the heart.
+
+The tones vary greatly in different hearts. A very strong third tone
+phase or prolongation of this phase usually means that the heart which
+produces the tone is a strongly acting one, although allowances must be
+made for a sclerosed artery in which there is a tendency to the
+production of a sharp third phase.
+
+Weakness of the third phase, as a rule, indicates weakness of the heart
+and this dulling of the third phase may be so excessive that no sound is
+produced. Goodman and Howell have carried this method further by
+measuring the individual phases and calculating the percentage of each
+phase to the pulse pressure. Thus, if in a normal individual the
+systolic pressure is 130 mm., the diastolic 85 mm., and the pulse
+pressure 45 mm., the first phase lasts from 130 to 116 or 14 mm., the
+second from 116 to 96, or 20 mm., the third from 96 to 91 or 5 mm., the
+fourth from 91 to 85, or 6 mm. The first phase would then be 31.1 per
+cent of the total pulse pressure, the second phase 44.4 per cent, the
+third phase 11.1 per cent, and the fourth phase 13.3 per cent. They
+consider that the second and third phases represent cardiac strength (C.
+S.) and the first and fourth represent cardiac weakness (C. W.). They
+believe that C. S. should normally be greater than C. W. In the example
+above C. S.:C. W. = 55.5:44.4. In weak hearts, especially in
+uncompensated hearts, the conditions are reversed and C. W. > C. S. This
+is often the case. As a heart improves C. S. again tends to become
+greater than C. W. They think that the phases should be studied in
+respect to the sounds and also to the encroachment of one sound upon
+another.
+
+These observations are interesting but we have not found the division
+into phases as helpful as it was thought to be. We spent a great deal of
+time on this question. All that can be said, in my opinion, is that a
+loud, long third phase is usually evidence of cardiac strength.
+
+A further interesting feature which can be heard in all irregular hearts
+is a great difference in intensity of the individual sounds. Goodman and
+Howell call this phenomenon tonal arrhythmia. Irregularities can be made
+out by the auscultatory method which can not be heard at the heart.
+
+In anemia the sounds are very loud and clear and do not seem to
+represent the actual strength of the heart.
+
+The general lack of vasomotor tone in the blood vessels together with
+some atrophy and flabbiness of the coats probably explains the loud
+sounds.
+
+In polycythemia the sounds have a curious, dull, sticky character and
+can not be differentiated accurately into phases, a condition which was
+predicted from the knowledge of the sharp sounds in anemia.
+
+In not all cases can all phases be made out. It is usually the fourth
+phase which fails to be heard.
+
+In such cases the loud third tone almost immediately passes to the fifth
+phase or no sound phase. The importance of this will later be taken up.
+
+"In arteriosclerosis, with hardening and loss of elasticity of the
+vessel walls, the auscultatory phenomena, according to Krylow, are apt
+to be more pronounced, since the back pressure at the cuff probably
+causes some dilatation of the vessel above it, while the lumen of the
+vessel is smaller than normal. Both of these factors cause an increased
+rapidity in the transmission of the blood wave when pressure in the cuff
+is released, which in time favors the vibration of the vessel walls.
+
+"In high grade thickening of the arterial walls, however, especially
+where calcification had occurred, Fischer found that the sounds were
+distinctly less loud than normal, the more so in the arm, which showed
+the greater degree of hardening. According to Ettinger's experience, the
+rapidity of the flow distinctly increases the auscultatory phenomenon."
+(Gittings.)
+
+The sounds depend upon the resonating character of the cuff, upon the
+size and accessibility of the vessel, upon the force of the heart beat,
+and upon the velocity of the blood.
+
+
+=The Maximum and Minimum Pressures=
+
+The maximum (systolic) pressure is read at the point where the first
+audible click is heard after the cuff is blown up and the pressure
+gradually reduced by means of the needle valve in the hand bulb or on
+the upright of the glass containing the mercury. All are agreed upon
+this point. There has been some dispute as to the place where the
+diastolic pressure should be read. Korotkov considered that the
+diastolic pressure should be read at the fourth phase when the loud tone
+suddenly becomes dulled. Others held that the diastolic pressure should
+be read at the fifth phase, the absence of all sound. Experiments
+carried out to determine this point were made by me with the assistance
+of Prof. Eyster and Dr. Meek at the Physiological Laboratory of the
+University of Wisconsin. We arranged apparatus making it possible to
+hold the pressure in the carotid artery of dogs at maximum or minimum. A
+femoral artery was then dissected and an instrument devised to compress
+the artery with a water jacket. The whole was connected up with a
+kymograph. A time marker was put in so as to record the place where
+changes in sound were heard while listening below the cuff around the
+femoral artery. Two sets of records were taken. One with pressure
+greater than minimum pressure and a falling pressure over the femoral
+artery (Fig. 29), the other with pressure at zero and gradually raised
+to minimum pressure (Fig. 30). Both sets of records showed the same
+result; viz., that at a point corresponding to the sudden change of tone
+the pressure on the artery corresponded to the minimum pressure. It was
+therefore concluded that experimentally in dogs the point where
+diastolic pressure should be read is at the tone change from clear to
+dull, not at the point where all sound disappears.
+
+[Illustration: Fig. 29.--Tracing of auscultatory phenomena. (See
+explanation in legend of Fig. 30.)]
+
+[Illustration: Fig. 30.--Figures are to be read from left to right. The
+top line records the points where sounds were heard, the figures above
+the short vertical lines refer to tones (see text). Mx. B. P., maximum
+blood-pressure. M. B. P., minimum blood-pressure. P. B., pressure bulb
+recorder. It was impossible to lower and raise this bulb by hand without
+obtaining the great irregular oscillations of the attached lever above
+the mercury manometer. B. L., base line.]
+
+Erlanger showed some years ago, that with his instrument, the point at
+which diastolic pressure should be read was at the instant when the
+maximum oscillation of the lever suddenly became smaller. While
+checking up the graphic with the auscultatory method using Erlanger's
+instrument, it was noticed that the disappearance of all sound did not
+correspond with the sudden diminution of the oscillation of the lever
+connected with the brachial artery. A series of records were carefully
+made on patients. It was seen that during the period of the third tone
+phase the oscillations of the lever on the drum reached a maximum (Fig.
+31) and remained at approximately the same height for some millimeters
+while the pressure was gradually falling. At a point at which the third
+tone, clear and distinct, became dull, there was an appreciable decrease
+in the height of the pulse wave. From this point to the disappearance of
+all sound there was a gradual diminution of the size of the pulse
+waves.
+
+[Illustration: Fig. 31.--Fast drum. Sudden decrease in size of pulse
+wave at 4, marking the change from clear sharp tone to dull tone.]
+
+[Illustration: Fig. 32.--Slow drum. Sudden decrease in amplitude at 4.]
+
+For normal pressures the difference between the fourth (dull) tone and
+the fifth (disappearance of all tone) phase, amounted to 4 to 10 mm.
+Occasionally the difference was so little, the change from sharp third
+tone through fourth dull tone to disappearance of all sound was so
+abrupt, that one could take the disappearance of all sound as the
+diastolic pressure, with an error of not more than 2 to 4 mm. This is
+within the limits of normal error and practically may be used by those
+who have difficulty in noting the change from third to fourth phase. For
+high pressures, however, the difference between fourth and fifth phases
+was never less than 8 mm., and was found as much as 16 mm. The
+diastolic, therefore, should always be taken at the fourth phase if
+possible.
+
+It was found that with the dial instrument the greatest fling of the
+lever corresponded to the third phase and the sudden lessened amplitude
+of the oscillation was at the fourth phase and was coincident with the
+change of tone from sharp to dull. Thus the diastolic pressure may be
+read off on the dial scale by watching the fling of the hand and with
+some practice one might acquire considerable accuracy. It is better,
+simpler, and, for most observers, more accurate to use the stethoscope
+and hear the change of sound.
+
+
+=The Relative Importance of the Systolic and Diastolic Pressures=
+
+The systolic pressure represents the maximum force of the heart. It is
+measured by noting the first sound audible over the brachial artery
+using the auscultatory method. It is the summation of two factors
+largely; the force expended in opening the aortic valves (potential) and
+the force expended from that point to the end of systole, the force
+which is actually driving the blood to the periphery (kinetic). To start
+the blood in motion, the heart must overcome a dead weight equal to the
+sum of all the forces holding the aortic valves closed. This sum of
+factors, called the peripheral resistance, must be reached and passed by
+the force of the ventricular beat before one drop of blood is set in
+motion along the aorta. This factor of resistance assumes a great
+importance.
+
+The systolic pressure is always fluctuating as it depends upon so many
+conditions, and the calls of the body except during sleep are many and
+various. In a study of diurnal variations in arterial blood pressure it
+has been found that--(1) A rise of maximum pressure averaging 8 mm. of
+Hg. occurs immediately on the ingestion of food. A gradual fall then
+takes place until the beginning of the next meal. There is also a slight
+general rise of the maximum pressure during the day. (2) The range of
+maximum pressure varies considerably in different individuals, but the
+highest and lowest maximum pressures are practically equidistant from
+the average pressure of any one individual.[4]
+
+ [4] Weyse, A. W., and Lutz, B. R.: Diurnal Variations in Arterial
+ Blood Pressure, Am. Jour. Physiol., 1915, xxxvii, 330.
+
+The pressure is lowest during sleep and gradually rises near the end of
+sleep, so that on awakening the pressure was the same as before sleep.
+
+Physiologically there are many conditions which modify the systolic
+pressure. Sleep, position, meals, exercise, emotional states cause often
+wide fluctuations which may be very sudden. It should be constantly
+borne in mind, that the systolic pressure reading which is made, is the
+maximum effort of the heart at that moment only.
+
+The diastolic pressure measures the peripheral resistance. It measures
+the work of the heart, the potential energy, up to the moment of the
+opening of the aortic valves. It is the actual pressure in the aorta.
+The diastolic pressure is not very variable; it is not subject to the
+same influences which disturb the systolic pressure. It fluctuates as a
+rule, within a small range. It is not affected by diet, by mental
+excitement, by subconscious psychic influences, to anything like the
+extent to which the systolic pressure is affected by the action of
+these factors. The diastolic pressure is determined by the tone in the
+arterioles and is under the control of the vasomotor sympathetic system.
+Any agent which causes chronic irritation of the whole vasomotor system
+produces increase in the peripheral resistance with consequent rise in
+the diastolic pressure. Any agent which acts to produce thickening of
+the walls of the arterioles, narrowing their lumina, produces the same
+effect.
+
+Such states naturally result in increased work on the part of the heart,
+which as a result, hypertrophies in the left ventricle. The increase in
+size and strength is a compensatory process in order to keep the tissues
+supplied with their requisite quota of blood. Conversely, paralysis of
+the vasomotor system produces fall of diastolic pressure which, if long
+continued, results in death.
+
+The diastolic pressure then is of importance for the following reasons:
+
+1. It measures peripheral resistance.
+
+2. It is the measure of the tonus of the vasomotor system.
+
+3. It is one of the points to determine pulse pressure.
+
+4. Pulse pressure measures the actual driving force, the kinetic energy
+of the heart.
+
+5. It enables us to judge of the volume output, for pulse pressure which
+is only determined by measuring both systolic and diastolic pressure, is
+such an index.
+
+6. It is more stable than the systolic pressure, subject to fewer more
+or less unknown influences.
+
+7. It is increased by exercise.
+
+8. It is increased by conditions which increase peripheral resistance.
+
+9. The gradual increase of diastolic pressure means harder work for the
+heart to supply the parts of the body with blood.
+
+10. Increased diastolic pressure is always accompanied by increased
+pulse pressure, and increased size of the left ventricle, temporarily
+(exercise) or permanently.
+
+11. Decreased diastolic pressure goes hand in hand with vasomotor
+relaxation, as in fevers, etc.
+
+12. Low diastolic pressure is frequently pathognomonic of aortic
+insufficiency.
+
+13. When the systolic and diastolic pressures approach, heart failure is
+imminent either when pressure picture is high or low.
+
+When all these factors are taken into consideration, it becomes apparent
+that the diastolic pressure is most important, if not the most important
+part of the pressure picture.
+
+Up to within a very brief time all the statistical evidence of blood
+pressure was based on systolic readings alone. This data is most
+valuable and much has been learned as to diagnosis and prognosis, but it
+is a mass of data based on a one-sided picture and can not be as
+valuable as the statistics which will undoubtedly be published later
+when all the pressure picture figures can be analyzed.
+
+
+=Pulse Pressure=
+
+The pulse pressure is the actual head of pressure which is forcing the
+blood to the periphery. At every systole a certain amount of blood 75-90
+c.c. (Howell) is thrown violently into an already comfortably filled
+aorta. The sudden ejection of this blood instigates a wave which rapidly
+passes down the arteries as the pulse wave. The elastic recoil of the
+aorta and large arteries near the heart contract upon the blood and keep
+it moving during diastole. Normally the blood-vessels are highly elastic
+tubes with an almost perfect coefficient of elasticity. The pulse
+pressure varies under normal conditions from 30 to 50 mm. Hg. There is a
+very definite relationship between the velocity of blood and the pulse
+pressure which is expressed thus; velocity = pulse rate x pulse
+pressure.[5]
+
+Further it has been demonstrated that under normal conditions and during
+various procedures--the pulse pressure is a reliable index of the
+systolic output.[6]
+
+ [5] Erlanger and Hooker: An Experimental Study of Blood Pressure and
+ of Pulse Pressure in Man, Johns Hopkins Hosp. Rep., 1904, xii, 145.
+
+ [6] Dawson and Gorham: The Pulse Pressure as an Index of Systolic
+ Output, Jour. Exper. Med., 1908, x, 484.
+
+Increased pulse pressure therefore goes hand in hand with greater
+systolic output. Physiologically this is most ideally seen during
+exercise. Following exercise the pulse rate increases, the systolic
+pressure rises greatly, the diastolic slightly or not at all. The pulse
+pressure therefore is increased. The velocity also is much increased.
+The call comes for more blood and the heart responds. In the chronic
+high pulse pressures there are four correlated conditions which, so far
+as I have studied them, are always present. These are: (1) An increase
+in size of the cavity of the left ventricle. The ventricle actually by
+measurement contains more blood than normal, and therefore throws out
+more blood at every systole. The volume output is greater per unit of
+time. (2) There is actual permanent increase in diameter of the arch of
+the aorta. This is a compensating process to accommodate the increased
+charge from the left ventricle. (3) There are on careful auscultation
+over the manubrium, particularly the lower half, breath sounds which
+vary from bronchial to intensely tubular, depending upon the anatomic
+placing of the aorta, the shape of the chest, and the degree of
+dilatation. Often there is very slight impairment of the percussion note
+as well. (4) There is increase in size of all the large distributing
+arteries, carotids, brachials, femorals, renals, celiac axis, etc., with
+fibrous changes in the media, loss of some elasticity, and increase in
+size of the pulse wave. Increased pulse pressure means increased volume
+output, but does not always mean increased velocity. The proper
+distribution of blood to the various organs of the body is regulated by
+the vasomotor system acting upon the small arteries which contain
+considerable unstriated muscle. When fibrous arteriosclerosis is present
+there is loss of elasticity in the distributing arteries and a greater
+volume of blood must be thrown out by the ventricle at every systole in
+order that every organ shall have its full quota of blood. A force which
+is sufficient to send blood through elastic normal distributing tubes
+becomes totally insufficient to send the same amount of blood through
+tortuous and more or less inelastic tubes.
+
+It is evident then that pulse pressure is exceedingly important. It can
+only be determined by measuring both the _systolic_ and _diastolic_
+pressure. The pulse rate must also be known in order to compute the
+velocity. It is essential to have the whole pressure picture for all
+cases if correct conclusions are to be drawn.
+
+In an irregular heart, especially in the cases due to myocardial
+disease, it is quite impossible to determine the true diastolic
+pressure. One can only approximate it and say that the pulse pressure is
+low or high. As a matter of fact the real systolic pressure can not be
+determined. For this figure the place on the scale where most of the
+beats are heard may be taken for the average systolic pressure. No one
+can seriously maintain that he can measure the diastolic pressure under
+all circumstances.
+
+By means of the auscultatory method of measuring blood pressure we are
+able to determine irregularities of force in the heart beats more easily
+than by listening to the heart sounds. A pulsus alternans is readily
+made out. The irregular tones heard over the brachial artery in cases of
+irregular heart action have been called "tonal arrhythmias."
+
+
+=Blood Pressure Variations=
+
+A recent study of diurnal variations in blood pressure has shown that
+while the maximum pressure rises after the ingestion of food and
+steadily rises slightly throughout the day, the minimum blood pressure
+is very uniform throughout the day, and is little affected by the
+ingestion and digestion of meals. When it is affected, a rise or a fall
+may take place. Throughout the day, it tends to become slightly lower.
+The pulse pressure then is greater towards evening.
+
+Weysse and Lutz in a study of this question draw the following
+conclusions:
+
+1. A rise of maximum pressure averaging 8 mm. of Hg occurs immediately
+on the ingestion of food. A gradual fall then takes place until the
+beginning of the next meal. There is also a slight general rise of the
+maximum pressure during the day.
+
+2. The average maximum blood pressure for healthy young men in the
+neighborhood of 20 years of age is 120 mm. of Hg. This pressure obtains
+commonly one hour after meals. The higher maximum pressures occur
+immediately after meals, and the lower, as a rule, immediately before
+meals.
+
+3. The range of maximum pressure varies considerably in different
+individuals, but the highest and lowest maximum pressures are
+practically equidistant from the average pressure of any one individual.
+
+4. The minimum blood pressure is very uniform throughout the day, and is
+little affected by the ingestion and digestion of meals. When it is
+affected a rise or fall may take place. There is a tendency for a slight
+general lowering of the minimum pressure throughout the day.
+
+5. The average minimum blood pressure for healthy young men in the
+neighborhood of 20 years of age is 85 mm. of Hg. Thus we get an average
+pulse pressure of 35 mm. of Hg.
+
+6. Pulse pressure, pulse rate, and the relative velocity of the blood
+flow are increased immediately upon the ingestion of meals. They attain
+the maximum, as a rule, in half an hour, and then decline slowly until
+the next meal. There is a general increase in each throughout the day.
+
+These measurements were made upon persons at rest. Almost any form of
+exercise would have made the variations much greater. No account is
+taken of the psychic variations which for the physician are the most
+important to bear in mind. Neglect to take this variation into account
+will inevitably lead to false conclusions.
+
+THE AVERAGE DIURNAL BLOOD PRESSURE RECORD OF THE TEN SUBJECTS
+
+==========+=======+=======+=======+=======+========+=======+===============
+ TIME |MAXIMUM|MINIMUM| MEAN | PULSE | PULSE |PP x PR| NOTES
+ | | | | |PRESSURE| RATE |
+----------+-------+-------+-------+-------+--------+-------+---------------
+ |_mm._Hg|_mm._Hg|_mm._Hg|_mm._Hg| | |
+4:30 p.m. | 119.5 | 84.1 | 101.8 | 35.4 | 72.0 | 2549 |
+5:00 p.m. | 117.7 | 83.5 | 100.6 | 34.2 | 71.1 | 2432 |
+6:00 p.m. | 118.0 | 84.0 | 101.0 | 34.0 | 74.9 | 2547 |Before dinner
+6:45 p.m. | 127.2 | 88.2 | 107.7 | 39.0 | 78.1 | 3046 |After dinner
+7:00 p.m. | 124.7 | 87.7 | 106.2 | 37.0 | 76.0 | 2812 |
+7:30 p.m. | 122.0 | 83.4 | 102.7 | 38.6 | 76.0 | 2934 |
+8:00 p.m. | 122.4 | 85.5 | 103.4 | 36.9 | 71.2 | 2527 |
+8:30 p.m. | 120.0 | 85.0 | 102.5 | 35.0 | 69.7 | 2439 |
+9:00 p.m. | 120.5 | 84.7 | 102.5 | 35.8 | 65.2 | 2334 |
+9:30 p.m. | 118.2 | 84.4 | 101.6 | 33.8 | 64.4 | 2177 |
+7:30 a.m. | 118.4 | 87.6 | 103.0 | 30.8 | 70.3 | 2165 |
+8:00 a.m. | 116.4 | 86.4 | 101.4 | 30.0 | 69.8 | 2094 Before breakfast
+8:30 a.m. | 124.2 | 85.4 | 104.8 | 38.8 | 79.4 | 3081 |After breakfast
+9:00 a.m. | 123.8 | 84.4 | 104.1 | 39.4 | 84.1 | 3313 |
+10:00 a.m.| 118.2 | 83.6 | 100.9 | 34.6 | 70.7 | 2446 |
+11:00 a.m.| 116.2 | 84.8 | 100.5 | 31.4 | 67.7 | 2126 |
+12:00 m | 114.4 | 83.2 | 98.8 | 31.2 | 66.2 | 2065 |Before luncheon
+12:30 p.m.| 122.8 | 83.2 | 103.0 | 39.6 | 70.9 | 2808 |After luncheon
+1:00 p.m. | 122.3 | 82.0 | 102.1 | 40.3 | 79.7 | 3212 |
+2:00 p.m. | 118.4 | 81.4 | 99.9 | 37.0 | 77.6 | 2871 |
+3:00 p.m. | 118.8 | 82.6 | 100.7 | 36.2 | 75.1 | 2719 |
+4:00 p.m. | 115.8 | 82.0 | 98.9 | 33.8 | 71.9 | 2420 |
+5:00 p.m. | 117.2 | 83.4 | 100.3 | 33.8 | 69.6 | 2352 |
+6:00 p.m. | 117.4 | 84.4 | 100.9 | 33.0 | 72.8 | 2402 |Before dinner
+6:45 p.m. | 124.6 | 83.1 | 103.8 | 41.5 | 80.4 | 3337 |After dinner
+7:00 p.m. | 125.2 | 84.2 | 104.7 | 41.0 | 76.1 | 3120 |
+7:30 p.m. | 122.0 | 84.0 | 103.0 | 38.0 | 73.7 | 2801 |
+8:00 p.m. | 119.6 | 85.0 | 102.3 | 34.6 | 72.3 | 2502 |
+8:30 p.m. | 119.7 | 84.0 | 101.3 | 34.7 | 69.0 | 2394 |
+9:00 p.m. | 120.0 | 86.2 | 103.1 | 33.8 | 68.0 | 2298 |
+ +-------+-------+-------+-------+--------+-------+
+ Average | 120.0 | 85.0 | 102.5 | 35.0 | 72.0 | 2550 |
+----------+-------+-------+-------+-------+--------+-------+---------------
+ (Taken from Weysse and Lutz.)
+
+In some experiments to determine the changes upon the blood pressure
+induced by hot and cold applications on and within the abdomen, Hammett,
+Tice and Larson found that heat applied to the outside of the abdomen
+raises the blood pressure. The application of cold produces no change.
+Either hot or cold saline introduced within the abdomen causes a fall in
+blood pressure.
+
+Experimentally, certain drugs such as adrenalin, barium chloride,
+nicotine, digitalis, strophanthus and the infundibular portion of the
+pituitary body known as pituitrin raise the maximum pressure. In the
+clinic it is difficult to conclude always whether the drug alone is
+responsible for rise in maximum pressure. Adrenalin given intravenously
+will raise the pressure. So will digitalis and strophanthus. I have
+watched the maximum pressure rise within three minutes following an
+intravenous injection of gr. 1/100 (0.0006 gm.) strophanthin 20 mm. of
+Hg: I have seen the subcutaneous injection of 10 minims of adrenalin
+repeated several times daily for six months fail to have the least
+effect on the blood pressure picture.
+
+Elevation of the foot of the bed about nine inches proved so efficacious
+in steadying failing hearts in acute infectious diseases, particularly
+typhoid, that a study was made of the effect upon blood pressure. Many
+observations were made, but no instrumental proof of rise in blood
+pressure could be adduced.
+
+Exercise always raises blood pressure, the maximum much more than the
+minimum. In athletes the minimum pressure may actually fall, the maximum
+rise so that a greater volume output results from the greater pulse
+pressure.
+
+Shock and hemorrhage lower it. Hemorrhage lowers also the pulse
+pressure, and it may be possible to prognosticate internal hemorrhage by
+frequent estimations of the systolic and diastolic pressures (Wiggers).
+Compression of the superior mesenteric artery or the celiac axis in dogs
+raises the blood pressure measured in the carotid artery for a period of
+at least an hour. This seems to be dependent on purely mechanical
+causes, and is not a reflex vasomotor phenomenon. (Longcope and
+McClintock.)
+
+Experimentally blood pressure can be increased by direct compression of
+the brain as Cushing has shown. It was thought at one time that in man
+the same effect would result from tumor of the brain or especially from
+subdural or extradural hemorrhage following head injuries. This,
+however, is not the case. No information of great value can be obtained
+by the measurement of blood pressure in these states. We do know that
+too high and too prolonged compression of the medulla brings about
+exhaustion of the cardiac center accompanied with rapid pulse, low
+pressure and eventual death.
+
+
+=Hypertension=
+
+All the conflict during the past few years over the subject of blood
+pressure has revolved around this much overworked word. Hypertension
+means high pressure, and yet it carries with it a suggestion of high
+pressure which is harmful to the individual. As a matter of fact
+hypertension is a compensatory process, it is often a saving process in
+spite of the fact that it carries possibilities of harm in its
+possessor. It has been made a fetish, a god to fall down before and
+worship and it has been the means of holding a torch of fear over a
+patient which has not been lost on the charlatans. Popularization of
+blood pressure has brought its crop of evils, no one of which has been
+as fruitful in dollars to unprincipled quacks as hypertension.
+
+Hypertension is the expression on the part of the circulation to meet
+new conditions in the tissues so that all tissues will be nourished and
+all will be enabled to function. Looked at from that point of view it is
+a conservative process and in many cases it is. It is not an average
+normal state, but it is normal state for the man who has it in chronic
+form. Hypertension should be viewed rationally and its proper place in
+the whole make-up of the patient determined. Hypertension is a relative
+term. What might be high pressure in a man of sedentary habits who
+reaches the age of fifty, might not be high pressure in a full blooded
+formerly athletic man of the same age. Temporary hypertension due to
+excitement, exercise, etc., must be kept in mind. It is not intended to
+convey the impression that hypertension is of no moment. It is a matter
+for investigation, but not a matter to worship as the all-in-all.
+
+Hypertension is, after all, a physiologic response on the part of the
+organism in order to maintain the circulation in equilibrium in the face
+of conditions which tend to produce vasoconstriction in large areas and,
+therefore tend to deprive these areas of blood. That there must be some
+substance in the blood stream which causes this constriction seems
+certain. What it is, is not at present known. Recently, Voegtlin and
+Macht[7] have isolated a crystalline substance from the blood of man and
+other mammals which they regard as a lipoid and closely related to
+cholesterin. This substance was recovered by them from the cortex of the
+adrenal gland. This becomes of added interest in the light of
+observations made by Gubar (quoted by Voegtlin and Macht). He noted
+"that the vasoconstricting properties of blood serum vary in different
+pathologic conditions, being increased in nephritis, for instance, and
+diminished in others." In some experiments made in the summer of 1913,
+we found there was no marked difference in the anaphylactic shock
+produced in half-grown rabbits by the injection of normal and uremic
+blood serum. As lipoids do not cause anaphylaxis, there should be no
+difference in the reaction of normal and uremic sera unless in one there
+was some form of protein not in the other. This does not seem to be the
+case. The presence of something in the circulation, therefore, produces
+constriction of vessels. This calls for more force in contraction on the
+part of the heart. This substance may be of lipoid nature. The continued
+presence of this hypothetical substance naturally would lead to
+hypertrophy of the heart.
+
+ [7] Isolation of a New Vasoconstrictor Substance from the Blood and
+ the Adrenal Cortex, Jour. Am. Med. Assn., 1913, lxi, 2136.
+
+What makes hypertension of significance is not the hypertension itself,
+but the fact that it is the expression of processes going on in the
+body which demand exhaustive investigation. To attach a blood pressure
+cuff to the arm, find the pressure, and diagnose hypertension is like
+putting a thermometer under the tongue, noting a rise in the mercury,
+and diagnosing fever. What causes the hypertension? Can the causes be
+removed? Those are the really vital questions after the symptom
+hypertension has been discovered.
+
+All states of hypertension are accompanied by more or less increase of
+pulse pressure. In other words the systolic pressure is always increased
+to greater degree than the diastolic pressure. In studies carried out in
+the wards and Pathological Laboratory of the Milwaukee County Hospital,
+Milwaukee, we found that in all of the cases of chronic high blood
+pressure with resulting high pulse pressure four correlated factors were
+found. If any one of these factors is present, the other three are
+found.
+
+1. In all high pulse pressure cases there is increase in the size of the
+cavity of the left ventricle. The ventricle actually contains more blood
+when it is full, and throws out, therefore, more blood at each systole.
+The actual volume output is greater per unit of time. Such hearts always
+show increase in thickness of the ventricular wall. I quite agree with
+Stone,[8] who says, "It is merely to be emphasized that when the pulse
+pressure persistently equals the diastolic pressure (high pressure
+pulse, in other words) with a resulting 50 per cent, _overload_, which
+means the expenditure of double the normal amount of kinetic energy on
+the part of the heart muscle, cardiac hypertrophy has occurred." They
+are found in aortic insufficiency, in chronic nephritis, in the diffuse
+fibrous type of arteriosclerosis, and in some cases of exophthalmic
+goiter. Such a condition occurs temporarily after exercise.
+
+ [8] Stone, W. J.: The Differentiation of Cerebral and Cardiac Types of
+ Hyperarterial Tension in Vascular Diseases, Arch. Int. Med., November,
+ 1915, p. 775.
+
+2. In all high pulse pressure cases there is actual permanent increase
+in diameter of the arch of the aorta. This is a compensating process to
+accommodate the increased charge from the left ventricle. Smith and
+Kilgore[9] have shown this to be true in cases of chronic nephritis with
+hypertension. Their research confirms my own observations. They found
+dilatation of the arch in (1) syphilis (that is, aortitis); (2) age over
+50 (that is, probable factor of arteriosclerosis); (3) other serious
+cardiac enlargement, and (4) hypertension (with more or less
+hypertrophy, as in chronic nephritis).
+
+ [9] Smith, W. H., and Kilgore, A. R.: Dilatation of the Arch of the
+ Aorta in Chronic Nephritis with Hypertension, Am. Jour. Med. Sc.,
+ 1915, cxlix, 503.
+
+In ten cases showing arches at the upper limit of normal (that is, 6 cm.
+in diameter) and hypertrophy of the heart, three were chronic mitral
+endocarditis; one was chronic aortic endocarditis; three were chronic
+mitral and aortic endocarditis, and there was one each of
+hyperthyroidism, pericarditis and adherent pericardium.
+
+In fourteen cases of hypertension (highest systolic 270 mm., average
+systolic, 215 mm.), all showed cardiac hypertrophy. "All but three of
+these cases had great vessels whose transverse diameters measured over
+the normal limit of 6 cm., and in one of those measuring 6 cm. the
+Roentgen-ray diagnosis was 'slight dilatation' of the arch." Smith and
+Kilgore are at a loss to explain the three exceptions. They did not give
+diastolic pressures, so pulse pressures are not known. Possibly the
+three exceptions were cases of high diastolic pressure in which the
+pulse pressure possible was not over 60 mm. Such cases might show
+"slight dilatation of the arch," but not marked dilatation, such as was
+found in the other, evidently high pulse pressure cases.
+
+We have found that only the high pulse pressure cases show dilatation of
+the arch. Certain high tension cases which have had a very high
+diastolic pressure do not reveal any accurately measurable dilatation of
+the aortic arch. An empty aorta after death is quite different from a
+functionating aorta during life. Hence the dilatation which is found
+postmortem must have been considerable during life. And conversely, a
+dilatation which was present during life might not be looked on as such
+after death.
+
+3. In all high pulse pressure cases one will find on careful
+auscultation over the manubrium, particularly its lower half, breath
+sounds which vary from bronchial to intensely tubular. At times the
+percussion note will be slightly impaired, as McCrae[10] has shown in
+dilatation of the arch of the aorta. This auscultatory sign is evidence
+of some more or less solid body in the anterior mediastinum which is
+lying on the trachea and permits the normal tubular breathing in the
+trachea to be audible over the upper part of the sternum. It is found in
+cases of dilated aortic arch. Fluoroscopic examination has confirmed the
+findings on auscultation.
+
+ [10] McCrae, Thomas: Dilatation of the Arch of the Aorta, Am. Jour.
+ Med. Sc., 1910, cxl, 469.
+
+4. In all high pulse pressure cases, in which the pulse pressure is over
+70 mm. of mercury, there is increase in the size of all large
+distributing arteries, carotids, brachials, femorals, renals, celiac
+axis, etc., with fibrous changes in the media, loss of some of the
+elasticity, and in the palpable superficial arteries, increase in size
+of the pulse wave.
+
+Increased pulse pressure means increased volume output, but does not
+always mean increased velocity. The proper distribution of blood to the
+various organs of the body is regulated by the vasomotor system acting
+on the small arteries which contain considerable unstriated muscle. In
+order that there may be enough blood at all times and under varying
+conditions of rest and function, there must be a proper supply coming
+through the distributing vessels, the large arteries, those containing
+much elastic tissue, and only a very small amount of unstriated muscle
+tissue or none whatever. Fibrous sclerosis of these vessels causes them
+to become enlarged and tortuous and to lose much of their elasticity,
+which is essential for the even distribution of blood. A greater blood
+volume is therefore necessary in order that the organs may receive their
+quota of blood. A force which is sufficient to send blood through
+elastic normal distributing tubes becomes totally insufficient to send
+the same amount of blood through tortuous and more or less inelastic
+tubes. As a compensatory process the pulse pressure increases. For this
+to increase, the left ventricular cavity dilates, the arch dilates, and
+as a greater force must be exerted to keep the increased mass in motion,
+the heart responds by hypertrophy of its left ventricle and becomes
+itself the subject of fibrous changes in the myocardium. The mass
+movement of blood is therefore greater in high pulse pressure cases than
+in cases of normal pulse pressure.
+
+In cases of chronic interstitial nephritis--contracted granular
+kidney--it may well be that the sclerosis of the arteries is a secondary
+process caused, as Adami thinks, by the hypertension itself. In aortic
+insufficiency the situation is somewhat different. The high pulse
+pressure is due to a very low diastolic pressure, for in my experience
+with uncomplicated aortic insufficiency the systolic pressure is, as a
+rule, not much increased above the normal for the individual's age. Here
+peripheral resistance is so low that a capillary pulse is common. The
+volume output per unit of time is greatly increased, the arch of the
+aorta is dilated, and the pulse is large. The fact that a large part of
+the blood regurgitates during diastole back into the ventricle, and the
+fact that the diastolic pressure is low means that there is no increased
+resistance to overcome, and the systolic pressure is not raised.
+
+Stone[11] has divided the cases of hypertension into the cerebral and
+cardiac types. He finds that there is a difference in prognosis and in
+the mode of death in the two groups. He has further attempted to judge
+of the work placed upon the heart by calculating what he calls the
+heart load or pressure-ratio. For example, he takes a normal pressure at
+120-80-40. The relation between 80 and 40 is 1/2 or 50 per cent. That he
+considers normal. When the heart load increases so that the pulse
+pressure equals or exceeds the diastolic pressure, the heart load is 100
+per cent or more, he considers the danger of myocardial exhaustion
+graver than when the heart load is normal or less than 50 per cent.
+
+ [11] Stone, W. J.: Arch. Int. Med., 1915, xvl, 775.
+
+It is his opinion, in which I heartily concur, "that an individual with
+a systolic pressure of 200 and a diastolic pressure of 140, is in
+greater danger of cerebral death than an individual with a systolic
+pressure of 200 and a diastolic pressure of 100." He is "likewise
+certain that the individual with a systolic pressure of 200 and a
+diastolic of 90 to 100 is in greater danger of a cardiac death. It is
+apparently the constant high diastolic pressure rather than the
+intermittently high systolic pressure which predisposes to cerebral
+accident."
+
+I have not been able to confirm all of Stone's conclusions. His
+contention holds good for some cases, but not, in my experience, for the
+great majority of the hypertension cases. I feel that in the
+classification of the chronic high pressure case we can go one step
+farther and split his first group into two usually differentiable
+groups. Syphilis is not an etiological factor in any of these groups. It
+is not considered that these groups are absolutely distinct and can
+always be rigidly separated. There are variations and combinations which
+render an exact separation impossible. But bearing this in mind the
+following classification is proposed as a working classification.
+
+Group A. Chronic nephritis.
+
+Group B. Essential hypertension.
+
+Group C. Arteriosclerotic hypertension.
+
+Group A. _Chronic Nephritis._ These are the cases with a high-pressure
+picture, that is to say, high systolic (200+) and high diastolic
+(120-140+). The pulse pressure is much increased. The palpable arteries
+are hard and fibrous. There is puffiness of the under eyelids, which is
+more pronounced in the morning on arising. Polyuria with low specific
+gravity and nycturia are present. There are almost constant traces of
+albumin in the urine, with hyaline and finely granular casts.
+
+Functionally these kidneys are much under normal. The functional
+capacity determined by Mosenthal's modification of the Schlayer-Hedinger
+method shows a marked inability to concentrate salts and nitrogen. The
+phthalein output is below normal. As the case advances the phthalein
+output becomes less and less, until a period is reached when there are
+only traces or complete suppression at the end of a two-hour period.
+Such patients may live for ten weeks (one of our cases) or longer, all
+the time showing mild uremic symptoms, and suddenly pass into coma and
+die.
+
+The natural end of patients in this group is either uremia or cardiac
+decompensation (so-called cardiorenal disease). Cerebral accidents may
+happen to a small number. It is only to this group, in my opinion, that
+the term cardiorenal disease should be applied. Formerly I believed that
+all high systolic pressure cases were cases of chronic nephritis of some
+definite degree. From the purely pathologic standpoint that is true, but
+from the important, functional standpoint it is far from being the true
+state of the cases.
+
+In this group there is marked hypertrophy and moderate dilatation of the
+left ventricle with dilatation and nodular sclerosis of the aorta. The
+kidneys are firm, red, small, coarsely granular, the cortex much
+reduced, the capsule adherent. Cysts are common. It is the familiar
+primary contracted kidney. Mallory calls this capsular-glomerulonephritis.
+The etiology is obscure. Often no cause can be found. Again, there is a
+history of some kidney involvement following one of the acute infectious
+diseases, or it may follow the nephritis of pregnancy. Usually, however,
+these cases fall into the group of secondary contracted kidneys, chronic
+parenchymatous nephritis.
+
+ Illustrative Case.--R. Z., a woman, aged thirty-six years, was seen
+ July 26, 1916, in coma. There was a history of typhoid fever at
+ nineteen years, but no other disease. She had had nine full-term
+ pregnancies, the last one thirteen months previously. For a week
+ before the onset of the present illness she had complained of severe
+ headaches and dizziness. There were no heart symptoms. For the past
+ year she has had nycturia. Physical examination revealed tubular
+ breathing beneath the manubrium, a few rales in the chest, an
+ enlarged heart (left side), with a systolic murmur over the aortic
+ area. Blood pressure was 178-125-53, the pulse rate 96, leucocytes
+ 27,250. Venesection of 500 c.c. of blood and intravenous injections
+ of 500 c.c. of 5 per cent NaHCO_3 in normal saline were employed.
+ Lumbar puncture withdrew 60 c.c. of clear fluid under pressure with
+ 6 cells per cubic millimeter. The eye grounds showed distinct
+ haziness of the disks and dilatation of the veins. Blood pressure
+ after venesection was 164-122-42, pulse 76, but in a few days rose
+ to 222-142-80, pulse 70. A second venesection of 400 c.c. and
+ proctoclysis of 1000 c.c. saline solution was tried. The
+ blood-pressure now was 198-140-58. The pH of the blood was 7.6, the
+ alkaline reserve was 35 volume per cent (van Slyke), and the CO_2
+ tension of the alveolar air (Marriott) was 25 mm. The phthalein on
+ the day following the second venesection was 45 per cent in two
+ hours. The urine at first showed 500 c.c. in twenty-four hours,
+ specific gravity 1016, albumin and casts. Later she passed 1300 to
+ 1600 c.c. with specific gravity around 1010. The blood-pressure
+ fluctuated considerably, reaching as low as 138-98-40, pulse 88. She
+ was discharged improved September 10, 1916. She had constant
+ headache but managed to keep up. In June, 1917, she suddenly died in
+ an uremic coma.
+
+Group B. This one might designate as the hereditary type, although there
+is not always a history in the antecedent. This group includes the
+robust, florid, exuberantly healthy people. They often are heard to
+boast that they have never had a doctor in their lives. They are usually
+thick-set or very large, fleshy people. The pressure picture is
+exceedingly high. The pulse pressure is moderately increased. The
+arteries are rather large, fibrous, and often quite tortuous, although
+this is not always the case. Some persons have hard, small, fibrous
+arteries. There is no puffiness beneath the eyes, no polyuria, and no
+nycturia as a rule. The urine is of normal amount, color, and specific
+gravity. Albumin is only rarely found and then in traces, but careful
+search of a centrifuged specimen invariably reveals a few hyaline
+casts. The phthalein excretion is normal or only slightly reduced. The
+kidneys excrete salt and nitrogen normally. It is in this group that
+apoplexy is found most frequently. The rupture of the vessel occurs when
+the victim is in perfect health, often without any warning. Occasionally
+when such a case recovers sufficiently to be around, cardiac
+decompensation sets in later and he dies then of the cardiac
+complications.
+
+Pathologically the hearts of such persons are found to have the most
+enormous hypertrophy of the wall of the left ventricle. The cavity is
+somewhat enlarged, as is always the case when the pulse-pressure is
+increased, but the size of the cavity is not the striking feature. The
+aorta is fibrous, thick walled, and the arch is slightly dilated. There
+are patches of arteriosclerosis. One such case seen only at autopsy had
+a rupture of the aorta just above the sinus of Valsalva and died of
+hemopericardium. The kidneys are of normal size, dark red, firm, the
+capsule strips readily, the surface is smooth or finely granular, the
+cortex is not decreased. The pyramids are congested and red streaks
+extend into the cortex. Microscopically the capsules of the glomeruli
+are a trifle thickened; a few show hyaline changes. There is rather
+diffuse, mild, round-cell infiltration between the tubules. The tubular
+epithelium shows little or no demonstrable changes. The arterioles are
+generally the seat of a moderate thickening of the intima and media, but
+it is not usual to find obliterating endarteritis. There is evidently a
+diffuse fibrous change which has not affected either the tubules or
+glomeruli to any great extent.
+
+ Illustrative Case.--L. C., a man, aged fifty-six years, stonemason
+ by trade, is a stocky, thick-necked individual. He had never been
+ ill in his life until a year ago, when he fell from his chair
+ unconscious. He had a right-sided hemiplegia which has cleared up so
+ completely that except for a very slight drag to his foot he walks
+ perfectly well. He came in complaining of shortness of breath and
+ cough. There was no swelling of the feet. Here evidently was
+ left-heart decompensation. Examination showed the blood pressure to
+ be 240-130-110, pulse irregular, 104 to the minute. There were
+ cyanosis and rales throughout both chests. The urine was normal in
+ color, specific gravity 1025, small amount of albumin, few casts,
+ hyaline and granular. The phthalein elimination was 65 per cent in
+ two hours. Under rest, purgatives, and digitalis he was much
+ improved. He has since had two other apoplectic strokes, the last of
+ which was fatal.
+
+When these patients are seen with acute cardiac decompensation, there
+are, of course, much albumin and many casts in the urine, and the
+phthalein output is, for the time being, decreased.
+
+Group C. This might be called the arteriosclerotic high-tension group
+(Stone's cardiac group). The cases are usually over fifty years old.
+They are men and women who have lived high and thought hard. Often they
+have had periods of great mental strain. Many men in this group were
+athletes in their young manhood. Many have been fairly heavy drinkers,
+although never drinking to excess. They are usually well nourished and
+inclined to stoutness. The pressure picture is high systolic with normal
+or only slightly increased diastolic and large pulse pressure. The
+arteries are large, full, fibrous, usually tortuous. The heart is very
+large, the apex far down and out. There is no polyuria; nycturia is
+uncommon, quite the exception. The urine is normal in color, amount, and
+specific gravity. Albumin is only rarely found and hyaline casts are not
+invariably present. The phthalein excretion is quite normal and the
+excretions of salt and nitrogen are also normal. The terminal condition
+in most of the patients in this group is cardiac decompensation. They
+may have several attacks from which they recover, but after every attack
+the succeeding one is produced by less exertion than the preceding one,
+and it becomes more and more difficult to control attacks. Eventually
+the patients become bed- or chair-ridden, and finally die of acute
+dilatation of the heart.
+
+Occasionally patients in this group may have a cerebral attack, but in
+my experience this is uncommon. Pathologically the heart is large, at
+times true _cor bovinum_, dilated and hypertrophied. The cavity of the
+left ventricle is much dilated. The aorta is dilated and sclerosed.
+
+The kidneys are increased in size, are firm, dark red in color, with
+fatty streaks in the cortex. The capsule strips readily and the cortex
+is normal in thickness or only slightly increased. The organ offers some
+resistance to the knife. The microscope shows small areas scattered
+throughout where the glomeruli are hyalinized, the stroma full of small
+round cells, the tubules dilated, and the cells are almost bare of
+protoplasm. Naturally the tubules are full of granular cast material.
+Also the arterioles show extensive intimal thickening, fibrous in
+character, with occasional obliterating endarteritis. One gets the
+impression that the small sclerotic lesions are the result of anemia and
+gradual replacement of scattered glomeruli by fibrous tissue. For the
+most part the kidney, except for the chronic passive congestion, appears
+quite normal. One can readily understand that in such a kidney function
+could not have been much interfered with.
+
+ Illustrative Case.--C. K., an active, stout, business man, aged
+ fifty-six years, consulted me on account of shortness of breath and
+ swelling of the feet in May, 1915. He had just returned from a
+ hospital in another city, where he had gone with what was apparently
+ cardiac decompensation. In his early manhood he had been a gymnast
+ and a prize winner. He has worked hard, often given way to violent
+ paroxysms of temper, has eaten heavily but drunk very moderately.
+ The heart was greatly enlarged, the arch of the aorta dilated, a
+ mitral murmur was audible at the apex. The radials and temporals
+ were large, tortuous, and fibrous. The blood pressure picture ranged
+ around 180-90-90. He was easily made dyspneic and had a tendency to
+ swelling of the lower legs. The urine was acid, of normal specific
+ gravity, normal in amount, normal phthalein, normal concentration of
+ salt and nitrogen, contained albumin only when he was suffering from
+ decompensation of the heart. Casts were always found. He finally
+ died, after sixteen months, with all the symptoms of chronic
+ myocardial insufficiency. The heart was enormous, a true _cor
+ bovinum_. The kidneys were typical of this condition, possibly
+ somewhat larger than usual.
+
+
+=Hypotension=
+
+When the pressure is constantly below the normal, it is called
+hypotension. This may be transient--as in fainting--it may be a normal
+state of the individual, it occurs in most fevers and in a great
+variety of diseases, including anemias.
+
+In arteriosclerosis, especially the diffuse (senile) type, the blood
+pressure is invariably low, and may be spoken of as hypotension. The
+heart in such a case is small, the muscle is flabby, there is brown
+atrophy of the fibers, and some replacement of the muscle cells by
+connective tissue. The same causes which have produced general
+arteriosclerosis have also produced sclerosis of the coronary arteries,
+and probably the lessened blood supply accounts for much of the atrophy
+of the heart muscle.
+
+In typhoid fever the maximum blood pressure during beginning
+convalescence may be as low as 65 mm. Hg. I have frequently seen
+hypotension of 80 mm. This is common.
+
+Meningitis is the only acute infectious disease in which the blood
+pressure is more often high than low. This is accounted for by the
+increased intracranial tension.
+
+Following large hemorrhages the blood pressure is reduced. In
+venesection the withdrawal of blood may not affect the blood pressure.
+The procedure is done to relieve overdistension of the heart.
+
+In pleurisy with effusion and in pericarditis with effusion there is
+hypotension.
+
+Collapse, whether from poisoning by drugs or as the result of dysentery,
+cholera, or profuse vomiting from whatever cause, reduces the blood
+pressure.
+
+In cachectic states, such as cancer, the blood pressure is low. General
+wasting of the whole musculature includes that of the heart and the
+heart muscle shows the condition known as "brown atrophy."
+
+A most interesting and important condition in which hypotension occurs
+is pulmonary tuberculosis. Haven Emerson has recently gone over the
+whole subject in a careful piece of work and his summary is as follows:
+
+"Hypotension or subnormal blood pressure is universally found in
+advanced pulmonary tuberculosis, in which condition emaciation may play
+a part in its causation. Hypotension is found in almost all cases of
+moderately advanced tuberculosis, or in early cases in which the toxemia
+is marked except when arteriosclerosis, the so-called arthritic or gouty
+diathesis, chronic nephritis, or diabetes complicate the tuberculosis
+and bring about a normal pressure or a hypertension. Occasionally the
+period just preceding a hemoptysis or during a hemoptysis may show
+hypertension in a patient whose usual condition is that of hypotension.
+
+"Hypotension has been found by so many observers in early, doubtful or
+suspected cases with or before physical signs of the disease in the
+lungs, and is considered by competent clinicians so useful a
+differential sign between various conditions and tuberculosis, that it
+should be sought for as carefully as it is the custom at present to
+search for pulmonary signs.
+
+"Hypotension when found persistently in individuals or families or
+classes living under certain unhygienic conditions should put us on our
+guard against at least a predisposition to tuberculosis. Most unhygienic
+conditions, overwork, undernourishment and insufficient air, are of
+themselves causes of a diminished resistance, and it seems likely that a
+failure of normal cardiovascular response to exercise or change of
+position may be found to indicate this stage of susceptibility,
+especially to tuberculous infection.
+
+"... Hypotension, when it is present in tuberculosis, increases with an
+extension of the process. Recovery from hypotension accompanies arrest
+or improvement. Return to normal pressure is commonly found in those who
+are cured. Continuation of hypotension seems never to accompany
+improvement. Prognosis can as safely be based on the alteration in the
+blood pressure as on changes in the pulse or temperature...."
+
+There are a few drugs which lower the blood pressure, but, as a rule,
+their effects are more or less transitory. We know of no drug, unless it
+be iodide of potassium, which has the property of causing changes in the
+blood (decrease in viscosity?), which tends to reduce the blood pressure
+when it is excessive. This drug fails us many times.
+
+
+SOME DRUGS WHICH INFLUENCE THE BLOOD PRESSURE
+
+ =Pressure Raisers=
+
+ Adrenalin, when injected directly
+ into a vein or deep into the muscles.
+ The action is transitory.
+
+ Caffeine, preferably in the form
+ of caffeine-sodium-benzoate. A good
+ drug.
+
+ Strychnine, which does not act directly
+ but seemingly through the
+ higher centers.
+
+ Ergot, somewhat uncertain.
+
+ Nicotine, not used therapeutically.
+
+ Camphor, used in sterile olive oil
+ and injected deeply into the muscles.
+
+ Digitalis, when the cardiac tone is
+ low and decompensation is present.
+ Its action is prolonged but slow. Injections
+ of the infundibular portion
+ of the pituitary body. Not in use
+ clinically.
+
+
+ =Pressure Depressors=
+
+ Nitroglycerine and amyl nitrite,
+ action transitory but rapid.
+
+ Sodium nitrite and erythrol tetranitrate.
+ Action somewhat more prolonged.
+
+ Aconite, veratrum viride, chloral,
+ etc. These depress the heart.
+
+ Purgatives, drastic and hydragogue.
+
+ Potassium and sodium iodide may
+ lower blood pressure. When they do,
+ the action is prolonged.
+
+ Diuretin and theocin-sodium-acetate.
+
+
+=Venous Pressure=
+
+Comparatively little work has been done upon the determination of the
+pressure in the veins in man. It is conceivable that this procedure may,
+at times, be of great value. A number of attempts have been made to
+measure the venous pressure by compressing the arm veins and noting on a
+manometer the force necessary to obliterate the vein. As the pressure is
+so slight, water is used instead of mercury, and readings have been
+given in centimeters of water.
+
+[Illustration: Fig. 33.--Apparatus for estimating the venous blood
+pressure in man, devised by Drs. Hooker and Eyster. The small figure is
+the detail of the box B. See explanation in text.]
+
+In the apparatus shown in the figure (Fig. 33), Drs. Hooker and Eyster
+succeeded in making estimations of the venous pressure. The box _B_ is
+held in position by the tapes _A_, so that the vein is visible through
+the rectangular opening in the thin rubber covering the bottom. The box
+is connected with the water manometer _G_, by a rubber tube, from which
+a T-tube enters the rubber bulb _E_. When the bulb _E_ is compressed
+between the plates _D_, by the coarse thumbscrew _C_, air is forced
+into the box _B_, exerting a pressure on the vein lying exposed beneath.
+This pressure is transmitted directly to the manometer =G=, and may be
+read off in centimeters of water on the accompanying scale. The veins of
+the back of the hand are used and there must be no obstruction between
+them and the heart. The rubber-covered box is accurately and lightly
+fitted over a vein and pressure made until it is obliterated. By
+measuring the distance above or below the heart level that the hand was
+when the observation was made, and subtracting or adding these figures
+to the manometer reading, we obtain the venous pressure at the heart
+level.
+
+Eyster has modified this instrument so that it is now much simpler to
+operate. He uses a small glass cup with a flaring edge and a diameter of
+about 2 cm. This is sealed to the skin directly over a vein on the back
+of the hand by means of collodion. The stem of the cup has a rubber tube
+leading to a small hand bulb and to the manometer tube which contains
+colored water. Slight compression of the hand bulb obliterates the vein
+which can be seen through the glass cup. The pressure in centimeters of
+water is then read off. (Fig. 34.) The principle is the same as in the
+earlier instrument, but the application is easier.
+
+[Illustration: Fig. 34.--New venous pressure instrument. (After
+Eyster.)]
+
+Practically Hooker and Eyster found that the normal variation in healthy
+subjects was from 3 to 10 cm. of water. The pressure rose in cases of
+decompensated hearts with dyspnea and venous stasis, and returned to
+normal with improvement in the condition of the patient. It might be
+possible with this instrument to foretell an oncoming decompensation by
+the rise in venous pressure.
+
+The venous pressure may also be estimated roughly by slowly elevating
+the arm and noting the instant at which a particular vein collapses. By
+measuring the height of the vein above the heart some idea may be
+obtained of the pressure within the right auricle.
+
+
+=The Pulse=
+
+There is nothing characteristic about the pulse of a person suffering
+from arteriosclerosis, except it be the difference in the pulse of high
+tension and of low tension. The pulse of high tension has a gradual
+rise, a more or less rounded apex, and the dicrotic wave is slightly
+marked and occurs about half-way down on the descending limb. In
+arteriosclerosis with low tension the radial artery is usually so rigid
+that very little pulse wave can be obtained. The general form of a low
+tension pulse is a sharp upstroke, a pointed summit, and a secondary
+wave on the base line, which corresponds to the dicrotic wave. Such a
+pulse can be easily palpated, and is known as a dicrotic pulse. However,
+such a pulse can occur only when the artery still retains all or a large
+part of its elasticity; hence in arteriosclerotic low tension we would
+never see such a pulse as the typical dicrotic.
+
+
+=The Venous Pulse=
+
+It would carry us too far to discuss fully the character of the venous
+pulse, but a brief summary of the essential features of the normal
+venous pulse is presented. The venous pulse is a term used to express
+the tracing obtained from the internal or external jugular vein at the
+root of the neck. Normally a very characteristic curve is produced,
+which can be readily analyzed into a series of waves corresponding to
+the fluctuations in the cardiac cycle. To understand these waves and
+their values, the accompanying figure is helpful. (Fig. 35.)
+
+[Illustration: Fig. 35.--Semidiagrammatic representation of the events
+in the cardiac cycle: Jug., pulse in the jugular vein; Aur., contraction
+of auricle; V. Pr., intraventricular pressure; Pap. M., contraction of
+the papillary muscles; Car., carotid pulse. Below are given the times of
+occurrence of the heart sounds and of the opening and closing of the
+heart valves. (After Hirschfelder.)]
+
+Bachmann summarizes the normal waves in the venous pulse tracing as
+follows:
+
+"The physiological or so-called venous pulse consists of three positive
+and three negative waves, bearing a more or less definite relation to
+the events of the cardiac cycle, and having their origin in the various
+movements of the chambers and structures of the right heart. The first
+positive wave (_a_) is presystolic in time, and is due to the
+contraction of the auricle, causing a slowing of the venous current and
+producing a centrifugal wave through a sudden arrest of the inflowing
+blood. The second positive wave (_S_) is presystolic in time, and
+originates in the sudden projection of the tricuspid valve into the
+cavity of the auricle during the quick, incipient rise in the
+intraventricular pressure occurring in the protosystolic period. The
+third positive wave (_v_) occurs toward the end of ventricular systole.
+It consists of two lesser waves separated by a shallow notch. The
+factors entering into its formation are the relaxation of the papillary
+muscle at a time when the intraventricular is still higher than the
+intraauricular pressure, resulting in an upward movement of the
+tricuspid leaflets and a return of the auriculoventricular septum to its
+position of rest.
+
+"The first negative wave (between positive wave _a_ and _S_) is due to
+the relaxing auricle. The second negative wave (_Af_) occurs during the
+diastole of the auricle. It is due to the dilatation of its walls, to
+the displacement of the auriculoventricular septum toward the apex
+occurring at the time of ventricular systole, and to the pull of the
+papillary muscles on the tricuspid valve leaflets. The third negative
+wave (_Vf_) appears during ventricular diastole and in the common pause
+of the heart chambers. Its cause is found in the passage of the blood
+from the auricle into the ventricle. It is somewhat modified possibly by
+the continual ascent of the auriculoventricular septum and by a wave of
+stasis due to the accumulation of blood coming from the periphery."
+(Fig. 36.)
+
+[Illustration: Fig. 36.--Simultaneous tracings of the jugular and
+carotid pulses showing normal waves in the venous pulse and relation to
+carotid pulse. (After Bachmann.)]
+
+Hirschfelder has described another wave which he calls the "h" wave,
+which is due to the floating up of the tricuspid valve by the blood in
+the ventricle before the complete filling of the ventricle following the
+auricular systole. (Fig. 37.)
+
+[Illustration: Fig. 37.--Jugular and carotid tracing from a normal
+individual with a well-marked third heart sound showing a large "h" and
+a smaller pre-auricular wave "w." ? indicates a small wave in
+mid-diastole following the "h" wave, occasionally found though perhaps
+an artefact. (After Hirschfelder.)]
+
+
+=The Electrocardiogram=
+
+In the past few years an immense amount of work has been done by
+numerous observers on the changes in the electrical potential of the
+various portions of the heart during contraction. The very elaborate and
+delicate electrocardiograph with the string galvanometer devised by
+Einthoven is used. It has been definitely determined that the impulse to
+cardiac contraction originates in the sinus node, a collection of
+differentiated nerve cells situated at the junction of the superior vena
+cava with the right auricle. From there the impulse travels in certain
+fibers in the interauricular wall, passes through another node, the
+auriculoventricular or Tawara node, situated in the auricular wall just
+above the auriculoventricular ring, thence via the Y-bundle, or bundle
+of His to the ventricles. This sequence is orderly, regular, and
+normally invariable. (Fig. 38.)
+
+[Illustration: Fig. 38.--Right side of the heart showing
+diagrammatically the distribution of the two vagus nerves to different
+parts of the viscus. The impulse to contraction originates at the
+sino-auricular node and passes over the wall of the auricle to Tawara's
+node, and thence over His' bundle across the auriculoventricular septum
+to be distributed throughout the ventricular wall. If the upper,
+sino-auricular, node is damaged, or if its impulses fail to get across
+the wall of the auricle, Tawara's node acts in its place to start off
+the ventricle. If a lesion at the base of the mesial segment of the
+tricuspid valve damages His' bundle, so that Tawara's node is cut off
+from the ventricle, then the ventricle may originate its own impulses to
+contraction. (Hare's Practice of Medicine.)]
+
+The sino-auricular (s-a) node is the most irritable portion of the
+heart, it is endowed with the greatest amount of rhythmicity as well.
+It is under the control of the vagus nerve. Its inherent rate of
+rhythmicity is probably more rapid than the usual numbers of impulses
+per minute, but it is inhibited by the vagus. Paralysis of the vagus
+endings increases the rate of impulse formation and therefore the rate
+of the heart.
+
+The electrocardiogram is a graphic representation on a photographic film
+or sensitive bromide paper of the changes of electrical potential during
+muscular activity. The lines are made by the highly magnified string of
+the galvanometer as it moves across the slit in the photographic
+apparatus in response to the induction currents set up in the heart
+magnified by the special galvanometer.
+
+The record is made in three so-called Leads.
+
+ Lead I
+
+ The electrodes are attached to right arm and left arm.
+
+ Lead II
+
+ The electrodes are attached to right arm and left leg.
+
+ Lead III
+
+ The electrodes are attached to left arm and left leg.
+
+A series of regular figures is normally obtained in which are
+depressions and elevations and regular spacing of these elevations and
+depressions. The waves so-called have been arbitrarily designated _P_,
+_Q_, _R_, _S_, _T_. There is some difference in the three leads. "The
+wave _P_ is positive in _all leads_. _P_ to _R_ interval varies slightly
+in the _three leads_. All the waves of _Lead II_ are greater than those
+of _Leads I_ and _III_. The wave _R_ is positive in _all leads_. _T_ is
+usually positive in _all leads_, but is occasionally negative in Lead
+III. Even in normal individuals there is a considerable range of
+variation in the electrocardiogram which is within the limits of the
+normal." (Hart.) (Fig. 39.)
+
+[Illustration: Fig. 39.--Normal electrocardiogram. (After Hart.)]
+
+The _P_ wave is admitted to be the wave of auricular contraction. _Q_,
+_R_, _S_, is the ventricular complex caused, it is thought, by the
+current passing over the ventricles. _T_ wave is not yet definitely
+settled. It has been thought by some that it represented actual
+ventricular contraction and its height and shape had some meaning in
+heart force. This is denied by others. Hart defines it as "The final
+activity of the ventricle." The _T_ wave is usually increased in size
+during exercise.
+
+The _P-R_ interval is almost the most important feature of the tracing.
+It is the actual conduction time in fractions of a second of the impulse
+from s-a node to the ventricles. Normally this is about 0.2 second or
+slightly less. Much that was hoped for from the electrocardiograph in
+the clinic has not been forthcoming. Its greatest value is in states of
+abnormal conductivity, such as various grades of heart block,
+extrasystoles, whether originating in auricles or in either ventricle,
+abnormalities of rhythm, as flutter and fibrillation. It has, however,
+aided materially in the intelligent interpretation of many phenomena
+heretofore not well understood, and has enormously increased our
+knowledge of the physiology and pathologic physiology of the heart.
+
+It is not possible to enter farther into the subject here. This brief
+discussion must suffice. The reader is referred to works on this subject
+in connection with diseases of the heart.
+
+
+
+
+CHAPTER IV
+
+IMPORTANT CARDIAC IRREGULARITIES ASSOCIATED WITH ARTERIOSCLEROSIS
+
+
+Arteriosclerosis of the aorta, of the coronary arteries, or of both, is
+practically always found in cases dying of various cardiac
+irregularities other than those the result of rheumatic cardiac lesions.
+It is not that arteriosclerosis causes the cardiac lesions (although the
+thickening of the walls of the coronary arteries does interfere
+mechanically with the nutrition of the heart muscle), but the
+arteriosclerosis is a part of the tissue reaction in the arteries to
+some set of causes affecting the whole body. It is true when one boils
+down the question to its last analysis, general arteriosclerosis may
+mechanically so interfere with the blood supply to tissues that the
+tissue is thrown out of function either in the reduction or even loss of
+function. So it may be that occasionally the arteriosclerosis in the
+arteries supplying the heart is really responsible for the cardiac
+irregularity. The past few years have been fruitful ones in increasing
+our knowledge of the various irregularities of the heart. We can do no
+more than sketch briefly some of them in relation to arteriosclerosis.
+
+The chief irregularities are (1) auricular flutter, (2) auricular
+fibrillation, (3) ventricular fibrillation, (4) auricular extrasystole,
+(5) ventricular extrasystole, (6) heart block, partial or complete.
+
+
+=Auricular Flutter=
+
+Auricular flutter is an abnormal rhythm characterized by very rapid, but
+rhythmic auricular contractions usually 250 to 300 per minute. The
+auricular contractions are so rapid that the ventricle can not respond,
+so that an electrocardiagram of a heart in such a state (Fig. 40) shows
+the ventricle beating regularly but at a much slower rate than the
+auricle.
+
+[Illustration: Fig. 40.--(After Hart.)]
+
+The majority of cases exhibiting this peculiar rhythm are over 40 years
+of age. In many cases sclerosis of the coronary arteries as a part of
+general arteriosclerosis has been found. Auricular flutter can be
+suspected when the pulse is regular or not particularly irregular and a
+fluttering, rapid pulsation is seen in the jugular vein on the right
+side. One can only be sure of the condition by making graphic records of
+the heart.
+
+Attacks usually come on suddenly and may disappear as suddenly,
+suggesting paroxysmal tachycardia. The patient feels a commotion in his
+chest, dyspnea, precordial distress, etc. The attack may last for weeks
+or months, in which case the patient may carry on his usual work but be
+conscious of palpitation in his chest. One may safely assume that the
+flutter is a sign of a failing myocardium and sooner or later the heart
+will pass to the graver stage of auricular fibrillation.
+
+
+=Auricular Fibrillation=
+
+In this condition the auricle is widely dilated and over its surface are
+countless twitchings of individual muscles giving to the auricle the
+appearance of a squirming bunch of worms. Such a condition may be
+readily produced in a dog's exposed heart by direct faradization of the
+auricle. It should be seen by every physician in order fully to
+appreciate the passive, dilated sac part which the auricle plays when in
+such a state. There is no auricular wave on the electrocardiogram (Figs.
+41 and 42) only a series of fine tremulous lines, and the ventricles
+beat irregularly with many dropped beats and variations in the size and
+force of individual beats. Extrasystoles are also frequent. The heart is
+absolutely irregular. Such a condition is readily recognizable as the
+state of broken compensation. Graphic records are not essential as in
+auricular flutter to establish the condition. Inspection of the root of
+the neck for jugular pulsations and examination of the pulse with the
+patient's evident dyspneic, cyanotic, edematous condition settles the
+diagnosis.
+
+[Illustration: Fig. 41.--Electrocardiogram showing auricular
+fibrillation in Leads I (upper) and II (middle and lower). (Courtesy of
+Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 42.--Auricular fibrillation. (After Hart.)]
+
+In no case of auricular fibrillation is the heart muscle free from
+extensive fibrous changes. These may be the result of general
+arteriosclerotic changes or may result from toxic changes. It is the
+general consensus of opinion that auricular fibrillation may persist for
+months or even years. Some hold that the state of perpetual irregular
+pulse is associated with auricular fibrillation. If that is true, then
+auricular fibrillation may last for many years. Patients may go about
+their work but always live with the imminent danger of a sudden
+dilatation of the ventricle and symptoms of acute cardiac
+decompensation.
+
+In these cases the blood pressure is of particular interest. It is often
+stated that the blood pressure is lowered as compensation returns and
+digitalis has exhibited its full action. As a matter of fact this
+statement needs some modification. If one takes the highest pressure at
+the strongest beat, which may be only one in a dozen or more, that may
+be true, but that does not represent the action of the much embarrassed
+heart. We know that the circulation is much interfered with, that there
+is hypostatic congestion, that the mass action is slow. The pulse
+pressure is greatly disturbed and the head of pressure which should
+force the blood to the periphery is so little that the circulation
+almost ceases.
+
+A count of the cardiac contractions heard with the stethoscope and a
+count of the pulse shows a great discrepancy in number. This has been
+called the "pulse deficit" (Hart). In order to arrive at the true
+average systolic pressure the following procedure is done. "The apex and
+radial are counted for one minute, at the same time by two observers,
+(if possible) then a blood pressure cuff is applied to the arm, and the
+pressure raised until the radial pulse is completely obliterated; the
+pressure is then lowered 10 mm., and a second radial count is made; this
+count is repeated at intervals of 10 mm. lowered pressure until the
+cuff-pressure is insufficient to cut off any of the radial waves
+(between each estimation the pressure on the arm should be lowered to
+zero). From the figures thus obtained the average systolic blood
+pressure is calculated by multiplying the number of radial beats by the
+pressures under which they came through, adding together these products
+and dividing their sum by the number of apex-beats per minute, the
+resulting figure is what we have called the 'average systolic blood
+pressure.'" (Fig. 43.)
+
+[Illustration: Fig. 43.--The shaded area represents the pulse deficit;
+the upper edge is the apex rate, the lower edge the radial rate. The
+broken line indicates the "average systolic blood pressure." (Compare
+these values with the figures at the bottom of the chart, which show the
+systolic blood pressure determined by the usual method.) (After Hart.)]
+
+For example: "B. S., April 29, 1910, Apex 131; radial, 101; deficit, 30.
+
+ BRACHIAL PRESSURE RADIAL COUNT
+ 100 mm. Hg. 0
+ 90 mm. 13 13 x 90 = 1170
+ 80 mm. 47 - 13 = 34 x 80 = 2720
+ 70 mm. 75 - 47 = 28 x 70 = 1960
+ 60 mm. 82 - 75 = 7 x 60 = 420
+ 50 mm. 101 - 82 = 19 x 50 = 950
+ ----
+ Apex = 131) 7220
+ ----
+ Average systolic blood-pressure 55 plus
+
+B. S., May 11, 1910, Apex 79; radial, 72; deficit 7.
+
+ BRACHIAL PRESSURE RADIAL COUNT
+ 120 mm. Hg. 0
+ 110 mm. 44 44 x 110 = 4840
+ 100 mm. 64 - 44 = 20 x 100 = 2000
+ 90 mm. 72 - 64 = 8 x 90 = 720
+ ----
+ Apex = 79) 7560
+ ----
+ Average systolic blood-pressure 95 plus"
+
+The diastolic pressure in these cases can not be determined except
+approximately. This may be done by using an instrument with a dial and
+noting the pressure where the oscillations of the dial hand show the
+maximum excursion. The diastolic pressure is not at all important under
+such conditions of acute cardiac breakdown. It would make no difference
+in treatment whether the case was one of pure cardiac disease or one
+of the hypertension groups. After the heart has rallied and the
+circulation is reestablished, then a careful determination of the
+diastolic pressure can be made and the prognosis will rest on what is
+found at the compensated stage.
+
+
+=Ventricular Fibrillation=
+
+Ventricular fibrillation as its name implies, is fibrillation of the
+ventricle analogous to that of the auricle, but the condition is rarely
+observed as it is incompatible with life. It has been shown that hearts
+at the time of death at times enter a state of fibrillation of the
+ventricles and that cases of sudden death may be due to this condition.
+Recently G. Canby Robinson[12] has seen and made electrocardiograms of a
+case of ventricular fibrillation. (Fig. 44.) The case was that of a
+woman forty-five years old, "who had a series of attacks of prolonged
+cardiac syncope, closely resembling Stokes-Adams syndrome, from which
+she recovered." During an attack of unconsciousness in which there was
+no apex beat for about four minutes, the electrocardiogram was taken.
+Following this the tracings showed an almost regular heart beating at
+the rate of 85 to 100 per minute. The patient had three convulsions and
+died with edema of lungs about 30 hours after the attack of ventricular
+fibrillation.
+
+ [12] Robinson, G. C., and Bredeck, J. F.: Arch. Int. Med., 1917, xx,
+ 725.
+
+[Illustration: Fig. 44.--Upper curve. Record obtained during period of
+cardiac syncopy at 2:48 p.m., Lead II. Lower curve from dog. Ventricular
+fibrillation observed in the exposed heart. Lead from right foreleg and
+left hind leg. (Courtesy of Dr. G. C. Robinson.)]
+
+Autopsy revealed chronic fibrous endocarditis of aortic and mitral
+valves, arteriosclerosis, bilateral carcinoma of the ovaries, and signs
+of general chronic passive congestion.
+
+It is possible that the syncopal attacks in this case were the result of
+sclerosis of the vessels supplying the heart muscle although careful
+microscopical examination did not throw much light on the ultimate
+cause.
+
+
+=Extrasystole=
+
+Whenever there is a dropped beat or an intermittent pulse one may be
+sure that it is the result of an extrasystole. Such extrasystoles are
+produced in the ventricle at some point other than the regular path of
+conduction of impulses. The extrasystole may have its origin in either
+the auricle or the ventricle. If there is auricular extrasystole it can
+not usually be recognized except by graphic methods. (Fig. 45.) The
+ventricular extrasystole on the contrary is commonly seen and readily
+recognized. Most of those seen in the clinic have their origin in some
+part of the ventricular wall. Their two characteristics are that they
+occur too early and that they are followed by a pause longer than the
+normal diastolic pause. (Fig. 46.)
+
+[Illustration: Fig. 45.--Electrocardiogram showing auricular
+extrasystoles (P). (Courtesy of Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 46.--Electrocardiogram showing ventricular
+extrasystole. Heart rate 56-60 beats per minute. Note that diastolic
+pause in which extrasystole occurs is practically equal to two normal
+diastolic pauses. (Courtesy of Dr. G. C. Robinson.)]
+
+When one listens over the chest to a heart when extrasystoles are
+occurring, one suddenly hears a weak beat which has taken place rather
+too early after the previous systole to be strong enough to effect the
+opening of the aortic valves. Consequently there is no pulse, the blood
+does not move, and that beat is lost to the circulation. Moreover, when
+the next regular stimulus comes from the s-a node it finds the ventricle
+in a refractory condition, having just ceased a contraction, and it is
+not until the next sinus impulse that the ventricle responds normally.
+(Fig. 46.)
+
+Patients who have occasional extrasystoles will say that all of a sudden
+the heart turns upside down in the chest. Sometimes there is slight
+sharp twinge of pain. Patients are at times quite alarmed about their
+condition. Provided there is no evidence of gross myocardial lesion, the
+extrasystole itself is of no great significance.
+
+While many cases showing pathologic causes for extrasystoles have more
+or less marked arteriosclerosis, there are other states in which no
+arteriosclerosis is found where the extrasystole is present.
+
+
+=Heart Block=
+
+As heart block occurs frequently in cases characterized by extensive
+arteriosclerosis, a brief discussion of the essential features will be
+given. It is, however, probable that arteriosclerosis is not the cause
+of any of the cases of heart block directly, but it is only a result of
+the same etiological conditions which produce the lesion or lesions
+which result in heart block. We may define heart block as the condition
+in which the auricles and ventricles beat independently of each other.
+There may be delayed conduction (Fig. 47), partial (Fig. 48), or
+complete heart block (Fig. 49). In the former there are ventricular
+silences, during which the auricles beat two, three, four, five, even up
+to nine times, with only one ventricular contraction. It is believed by
+most physiologists that the essential factor in the production of heart
+block is an interference in the conduction of impulses from the
+auricles to the ventricles through the band of tissue known as the
+auriculoventricular bundle.
+
+[Illustration: Fig. 47.--Electrocardiogram showing delayed conduction
+(lengthening of P-R interval). These P-R intervals are quite regular.
+When irregular there is apt to be extrasystole of ventricle or
+occasional blocking of impulse going to ventricle. (Courtesy of Dr. G.
+C. Robinson.)]
+
+[Illustration: Fig. 48.--Electrocardiogram showing partial heart-block
+in the three leads. Note the variability of P-R interval calculated in
+seconds in Lead II. (Courtesy of Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 49.--Complete heart block. (Courtesy of Dr. G. C.
+Robinson.)]
+
+The bundle of muscles described by His in 1905, connecting the auricles
+and ventricles, has been definitely shown to be the path through which
+impulses having their origin in the orifices of the great veins pass to
+the ventricles. The situation and size of this bundle has been thus
+described in man by Retzer:
+
+"When viewed from the left side, the bundle lies just above the muscular
+septum of the ventricles and below the membranous septum. In some hearts
+the muscular septum is so well developed that it envelops the bundle. It
+is then difficult to find, but occasionally it can be seen directly by
+means of transmitted light. From the left side the bundle can be
+followed no farther posteriorly than the right fibrous trigone, for here
+the connective tissue becomes so dense that it is difficult to dissect
+it away. The impression is, therefore, received that this mass of
+connective tissue forms the insertion of the bundle. The bundle may be
+followed anteriorly until it becomes intimately mixed with the
+musculature of the ventricles.
+
+"When viewed from the right side of the heart, the bundle can not be
+seen, because it is covered by the mesial leaflet of the tricuspid
+valve, whose line of attachment passes obliquely over the membranous
+septum. Then, if the endocardium is removed from the posterior part of
+the septum of the auricle up to the membranous septum, the posterior
+part of the auriculoventricular bundle will be exposed. If, in addition,
+the membranous septum be removed, the bundle may be traced from the
+point to which it could be followed when viewed from the left side as it
+passes posteriorly over the muscular septum. In the region of the
+auriculoventricular junction it loses its compactness, the fibers
+divide, and the bundle seems to fork. One branch passes into the
+superficial part of the valve musculature which descends from the
+auricles, and the other branch passes directly into the musculature of
+the auricle.
+
+"Briefly, the auriculoventricular bundle runs posteriorly in the septum
+of the ventricles about 10 mm. below the posterior leaflet of the aortic
+semilunar valves; with a gentle curve it passes posteriorly just over
+the upper edge of the muscular septum and sends its fibers into the
+musculature of the right auricle and of the auricular valves. In the
+heart of the adult the bundle is 18 mm. long, 2.5 mm. wide, and 1.5 mm.
+thick." (Erlanger.)
+
+All normal impulses have their origin in the sino-auricular node at the
+junction of the superior vena cava with the right auricle (Fig. 50).
+From there the impulse travels in the wall of the auricle in the
+interauricular septum to the node of Tawara or A-V node (Fig. 51),
+thence through the bundle of His to be distributed to the fibers of the
+right and left ventricles. This sequence is orderly and perfectly
+regular.
+
+[Illustration: Fig. 50.--Showing alternating periods of sinus rhythm and
+auriculoventricular rhythm. (After Eyster and Evans.)]
+
+[Illustration: Fig. 51.--Period of auriculoventricular or "nodal" rhythm
+following exercise in sitting posture. (After Eyster and Evans.)]
+
+It has also been shown that the independent auricular and ventricular
+rates vary somewhat, that of the auricle being in general faster than
+that of the ventricle. A strip of mammalian ventricle placed outside of
+the body in proper surroundings will begin to beat automatically at the
+rate of about 40 beats a minute. Experimentally various grades of heart
+block have been produced in the dog's heart by more or less compression
+of the bundle at the A-V ring. The block may be partial, when two to
+nine auricular beats occur to every one of the ventricle, up to
+absolute complete block when the auricles and ventricles beat
+independently of one another.
+
+In any stage of partial block, pressure on the vagus nerve in the neck
+produces certain specific changes. (Fig. 52.) Robinson and Draper[13]
+have found qualitative differences in the two vagi. The right vagus
+sends most of its fibers to the s-a node (Fig. 53) and has a more
+evident influence on the rate and force of the cardiac contractions. The
+majority of fibers from the left vagus are distributed to the A-V node
+so that its most evident action is upon the conductivity of the impulse.
+Pressure then on the right vagus will have a tendency to slow the whole
+heart. Pressure on the left vagus will have a tendency to prolong the
+P-R interval until even complete block occurs. Even when the heart block
+is complete, stimulation of the accelerator nerve, as a rule, increases
+the rate of both auricles and ventricles.
+
+[Illustration: Fig. 52.--Influence of mechanical pressure on the right
+vagus nerve. (After Eyster and Evans.)]
+
+[Illustration: Fig. 53.--Schematic distribution of right and left vagus.
+(After Hart.)]
+
+ [13] Jour. Exper. Med., 1911, xiv, 217.
+
+If the block is functional, depending upon some temporary
+overstimulation of the vagus nerve, atropin, which paralyzes the endings
+of the vagus, will naturally lift the block. If the block is due to some
+actual lesion of the bundle of His, such as fibrosis, gumma, or other
+lesion, then atropin will have no influence to terminate the block. In
+this manner we are able to distinguish between functional and organic
+heart block.
+
+
+
+
+CHAPTER V
+
+BLOOD PRESSURE IN ITS CLINICAL APPLICATIONS
+
+
+It is well to bear constantly in mind the point made over and over in
+this work, that blood pressure is only one of many methods of acquiring
+information. He who worships his sphygmomanometer as a thing apart and
+infallible will sooner or later come to grief. Judgment must be used in
+interpreting changes in blood pressure just as judgment is essential in
+properly evaluating any instrumental help in diagnosis. One must not
+forget the personal equation which enters into even accurate
+instrumental recording in medicine and surgery.
+
+In this chapter there will be no attempt to quote largely from what
+others have said or thought. Every one has his own opinion as to the
+value of certain methods after he has worked with them for a long time.
+The ideas here expressed, except in cases where no opportunity has
+offered to make personal studies, are those gathered from personal
+experience.
+
+
+=Blood Pressure in Surgery=
+
+Careful estimation of the blood pressure in surgical cases has, at
+times, great value. In all surgical diseases the most important fact to
+know is not the systolic pressure, but the pulse pressure. If the pulse
+pressure keeps within the range of normal, does not drop much below 30
+mm. in an adult, then so far as we can tell the circulation is being
+carried on. When the systolic pressure is gradually falling and the
+diastolic remains the same, the circulation is failing and unless the
+pulse pressure can be established again the patient will die. Again we
+see the value of the pulse pressure.
+
+All prolonged febrile diseases tend to produce a lowering of the blood
+pressure picture. The diastolic does not fall to the same extent as the
+systolic so that there is a pulse pressure smaller than normal. This is
+to be expected from what we know of the general depression of the
+circulation in fevers. The blood pressure reading is only a graphic
+record of what we have long known, and enables us from day to day
+accurately to measure the general circulation.
+
+
+=Head Injuries=
+
+It was claimed that in fracture of the skull or in concussion much could
+be gained by frequent estimations of the blood pressure. This seemed
+probable in the light of experiments on compressing the brains of dogs
+by the use of bags inserted through trephine openings (Cushing). In the
+clinic, however, it has not been found of any material value. It has a
+value in differentiating a simple fracture, let us say, from a case of
+uremia which is picked up on the street with a bump on the head. There
+the high pressure usually found would at once direct attention to the
+kidneys and the newer methods of blood examination would at once settle
+the question. Naturally uremics may also have skull fracture. There the
+diagnosis would be complicated. A decompression done at once would be
+indicated. If the skull fracture happened in a uremic, the decompression
+would probably do no harm. In fact, there are some who advise
+decompression for uremia.
+
+
+=Shock and Hemorrhage=
+
+In shock the blood pressure picture is low but the pulse pressure drops
+to abnormally low figures. It seems to me that the blood pressure
+instrument has its greatest value in surgery in the warning it gives to
+the operating surgeon in cases of impending shock.
+
+It is well known that the first effect of ether, the commonly used
+anesthetic, is to raise the blood pressure and quicken the pulse rate.
+The whole blood pressure picture is at first elevated (Fig. 54). Soon
+the whole pressure falls slightly but continues at a higher level than
+normal. The diastolic pressure drops back nearly to normal and the
+increased pulse pressure is due almost entirely to the slight rise in
+the systolic pressure. Now the whole duty of the anesthetist is to
+administer the ether so that this ratio of systolic and diastolic is
+maintained throughout the operation. Warning comes to him of impending
+shock before it comes to any one in the neighborhood (Fig. 55). Any
+sudden change in the pressure is a signal for increased watchfulness.
+Should the pressure all at once drop he can immediately notify the
+surgeon and institute measures to resuscitate the patient.
+
+[Illustration: Fig. 54.--Blood pressure record from a normal reaction to
+ether. Note that the systolic and diastolic rise and fall together. At
+the end of the anesthetization the pulse pressure is practically the
+same as at the beginning. Compare this with the record in Fig. 55, where
+the operation had to be discontinued on account of the onset of shock.]
+
+[Illustration: Fig. 55.--Beginning of operative shock. Chart showing the
+method of recording blood pressure during operation.
+
+Note that the pulse and respiration show no remarkable changes, but the
+blood pressure steadily fell, the systolic more than the diastolic so
+that the pulse pressure was gradually reaching the danger point. Further
+work on this case was stopped following the warning given by the blood
+pressure. The patient was returned to the ward and a week later
+anesthesia was again given, the operation was completed, and the patient
+had a satisfactory convalescence.]
+
+A method which is widely used is as follows: The anesthetist wraps the
+cuff of one of the dial instruments around the patient's arm, and
+arranges the dial so that it can easily be seen by him at all times.
+This does not in any way interfere with the work of the surgeon. Over
+the brachial artery below the cuff is the bell of a binaural stethoscope
+held in place by the strap attachment now on the market. The tubes of
+the stethoscope are long enough to reach conveniently to the ear pieces.
+A watch is pinned to the sheet of the table. He has a chart, as
+illustrated (Fig. 56) on a board and makes a dot in every space for five
+minute intervals. By joining the lines a curve is obtained which tells
+at a glance what the circulation is doing. I feel sure that more
+attention and care exercised on the part of the anesthetist would be the
+means of conserving many lives lost from shock following operation.
+
+[Illustration: Fig. 56.--Showing method of using blood pressure
+instrument during operation without interfering with the operator or
+assistants. Sheet thrown back to show cuff on arm of patient.
+Anesthetist has chart on table beside him, dial pinned to pad in full
+view, bulb near hand. Extra tubing must be put on the blood pressure
+instrument.]
+
+A sudden drop in the pressure picture may mean a large hemorrhage. The
+gradual return of the pressure picture means that the vasomotor
+mechanism has acted to keep up the pulse pressure. Should the diastolic
+pressure continually fall, it may mean that the hemorrhage is still
+taking place (Wiggers).
+
+
+=Blood Pressure in Obstetrics=
+
+One might affirm almost without fear of contradiction that the constant
+determination of blood pressure during pregnancy is more important than
+the examination of the urine. Within recent years a number of observers
+having access to a large material, have given the results of their
+findings. There is a striking unanimity of opinion, although now and
+then a difference in minor details.
+
+The blood pressure should be taken frequently during pregnancy. The
+usual and highly essential precautions in taking pressure in general
+apply most particularly in these cases. Towards the end of pregnancy the
+pressure should if possible be taken daily and oftener if necessary.
+
+Pressure in women is usually below 120 mm. Many patients have a
+temporary rise in blood pressure during pregnancy, due oftenest to
+constipation, without developing other symptoms. This is common to all
+conditions and has no significance. Some think that an abnormally low
+pressure, that is, a systolic below 90 mm., suggests that the patient is
+likely to react unduly to the strain of labor. This is denied by others.
+Among 1000 cases (Irving) the pressure was below 90 in only one case. A
+gradually rising pressure precedes albuminuria, as a rule. If there is
+albumin without change in pressure the albumin may usually be
+disregarded. Some think that a pressure over 130 mm. systolic should be
+carefully watched. The danger limit is set by some at 150 mm. If the
+blood pressure from the very first is high, it may mean only that that
+was the patient's normal pressure. This calls for increased
+watchfulness. It is held by some that high blood pressure favors
+hemorrhage and probably explains the hemorrhagic lesions in the placenta
+and some viscera in eclampsia and albuminuria.
+
+All are agreed that the most significant change is the gradual but sure
+rise from a low pressure. When this is combined with albuminuria the
+danger of toxemia is imminent. The high blood pressure in those under
+thirty years of age seems to be a more certain sign of approaching
+toxemia than the same pressure in those older. The pressure falls within
+a few days to its normal after delivery in the toxic cases.
+
+Although the emesis gravidarum is held to be a sign of a toxemia of some
+unknown nature, the blood pressure is never raised even in the
+pernicious form.
+
+
+=Infectious Diseases=
+
+In all infectious diseases the blood pressure tends to be lower than
+normal. During chills the systolic may rise to great height due to the
+violent muscular contractions.
+
+We found the blood pressure of great value in giving information
+concerning the circulation. Again we repeat that it is not the systolic
+alone or the diastolic alone but the pulse pressure which we wish to
+keep informed about. In pneumonia we have tried out Gibson's law only to
+discard it. This so-called law is that in pneumonia the systolic
+pressure in millimeters should remain above the figure for the pulse
+rate. When the figure in mm. of pressure is equalled by or exceeded by
+the pulse rate the prognosis is grave.
+
+In typhoid fever we have made many estimations at various stages of the
+disease. We can only say that the pressure picture tends to fall during
+the course. The systolic falls more than the diastolic so that it is not
+uncommon to see pulse pressures of 20 mm. at the beginning of
+convalescence in spite of the high caloric feeding practiced. At the
+time of perforation the systolic pressure may be raised. This is only
+the reflex from the initial pain. Soon the pressure falls and if
+peritonitis sets in, the pressure is exceedingly low and the pulse
+pressure gradually falls until the circulation can no longer be carried
+on. In large hemorrhage the pressure suddenly falls. If only one
+hemorrhage has occurred a gradual rise takes place, but the general
+pressure picture remains at a lower level for days, gradually returning
+where it was before the hemorrhage.
+
+In beginning failure of the circulation we found elevation of the foot
+of the bed about nine inches to be of such value that we felt there must
+be some increase in blood pressure. Numerous readings were made covering
+a period of several months. Although we felt certain that the
+circulation was improved, we rarely needed cardiac stimulation, we never
+could prove any increase of blood pressure with the sphygmomanometer.
+
+In all infectious diseases there is no help offered by blood pressure
+estimations in diagnosis. The sole and important use is that of keeping
+track of the circulation.
+
+
+=Valvular Heart Disease=
+
+No rules can be laid down for blood pressure in valvular heart disease.
+Aortic stenosis, the rarest of the valvular lesions, is practically
+always accompanied by high pressure picture. Mitral stenosis on the
+contrary usually shows a low pressure picture. Mitral insufficiency may
+show an exceedingly low picture or an exceedingly high picture. Aortic
+insufficiency also may be accompanied by a high systolic or by a normal
+systolic pressure. It depends on the etiology. Practically all the
+rheumatic cases have low pressure, the syphilitic cases have a high
+pressure. It is characteristic of all cases of aortic insufficiency that
+the diastolic pressure is low, even as low as 30 mm. The pulse pressure
+is invariably high. Usually there is no difficulty in determining the
+diastolic pressure. The intense third tone suddenly becomes dull at the
+point of diastolic pressure and frequently the dull sound can be
+distinctly heard over the artery down to the zero of the scale. If
+difficulty is found in reading the diastolic as the pressure is reduced,
+the estimation may be reversed and the pressure gradually increased from
+zero to the point where the dull tone suddenly becomes loud and clear.
+These points always coincide.
+
+
+=Kidney Diseases=
+
+This has already been discussed somewhat fully in Chapter III and will
+receive more consideration later. It might be remarked in passing that
+in a case of seeming coma where albumin is found in the urine but where
+the blood pressure is low or normal, I have found at autopsy in several
+cases pyonephrosis and not chronic nephritis. The blood pressure may be
+useful in differentiating uremic coma from the coma of pyonephrosis.
+Also in the cases of coma with anasarca, either the acute, subacute or
+chronic form the blood pressure is not raised as a rule. Other diseases
+of the kidney, as tuberculosis, cancer, infection with pyogenic
+organisms, are not accompanied with any notable changes in blood
+pressure.
+
+
+=Other Diseases, Liver, Spleen, Abdomen, etc.=
+
+Blood pressure is only of value in the above diseases in affording
+information concerning the state of the circulation. There is nothing
+characteristic about the pressure in any of these diseases.
+
+
+
+
+CHAPTER VI
+
+ETIOLOGY
+
+
+The causes of arteriosclerosis are many and varied. No two persons have
+the same resisting power toward poisons that circulate in the blood.
+Some go through life exposed to all the infectious diseases without ever
+becoming infected, while others fall easy victims to every disease that
+comes, no matter how careful they may be, and it is quite the same in
+regard to the resistance of the arterial tissues. If the tubing is of
+first class quality and the individual does not place too much strain on
+it, he may live to the biblical three-score years and ten, and possess
+arteries which have undergone such slight changes that they are not
+palpable. Such a person is, however, the exception. On the other hand,
+if the tissue is of poor quality, even the ordinary wear and tear of
+life causes early changes in the vessels, and a person of forty may have
+hard arteries.
+
+We have described in a previous chapter the changes which normally occur
+in the arteries as age advances. An artery that is normal for a man of
+fifty years would be distinctly abnormal for a boy of fifteen.
+
+Two broad divisions of arteriosclerosis may be made: (1) congenital, or
+the result of inherited tendency; (2) acquired.
+
+
+=Congenital Form=
+
+When Dr. O. W. Holmes was asked how to live to the age of seventy, he
+replied that a man should begin to pick his ancestors one hundred years
+before he was born. Our parents determine the character of the tissues
+with which we start in life, and this determines our general resistance.
+We might properly speak of congenital arteriosclerosis where the
+affected individual had poor arterial tissue with which to begin life,
+for that, in a sense, is a congenital defect, and arterial tissue that
+is poor in quality is prone to disease.
+
+The author is more and more impressed with the part that heredity plays
+in the determination of arterial degeneration. Especially does syphilis
+in the parents or grandparents leave its stigma in the succeeding
+generations in the shape of poor arterial tissue which is prone to early
+degeneration. Recently W. W. Graves has called attention to a
+malformation of the vertebral border of the scapula which consists in a
+concavity instead of the normal convexity of the bone. To this
+malformation he has given the name, scaphoid scapula. He considers this
+to be but one manifestation of a general lack of development in the
+individual. He speaks of this maldevelopment as a blight and considers
+that syphilis in the ancestors is responsible for the condition in the
+offspring. He finds that even in children, the subjects of the scaphoid
+scapula, the arteries are very definitely thickened. While confirmation
+of his observations is lacking, there is no doubt that we must lay the
+blame for much of the arteriosclerosis in our patients to the poor
+quality of arterial tissue transmitted by ancestors who have acquired
+some constitutional disease. It may have been syphilis, it may have been
+the degeneration produced by alcohol or other drug. We can not ignore
+the part which heredity plays. The various factors to be considered in
+the production of the acquired form of arteriosclerosis appear to me to
+be but contributory factors to a very great extent, the essential and
+fundamental factor being the quality of arterial tissue with which the
+individual is endowed.
+
+Arteriosclerosis may occur in infants. Cases have been reported of
+calcification of the arteries in infants and children. The
+arteriosclerosis may occur without nephritis or rise of blood pressure.
+Cerebral hemorrhage in a child of two years has been seen. Heredity in
+these cases plays a most important rôle. In many of the reported cases
+there was no question of congenital syphilis. Aneurysms, single or
+multiple, have been found in the arteries of children, and even the
+pulmonary artery may show sclerotic changes.
+
+
+=Acquired Form=
+
+As a rule the cases usually seen belong in this group because it seems
+as if a connection could be established almost always between one or
+more of the etiologic factors to be described and the disease. While
+this apparently is the case, we must never lose sight of the part which
+the quality of the tissue plays. When we leave this out of our
+calculations we undoubtedly make many false deductions. When two men of
+the same age who have been exposed to the same conditions as far as we
+can learn, are found to have quite different arteries, the one normal,
+the other thickened, we must postulate congenitally poor tissue on the
+part of the latter. Such tissue readily becomes diseased following
+conditions which would very likely have produced no noticeable effect on
+perfectly normal, healthy tissue.
+
+
+=Hypertension=
+
+Hypertension must still be reckoned with in the etiology of
+arteriosclerosis although the rôle that it was thought to play does not
+seem so important. Changes of blood pressure alone are not considered by
+many to be sufficient for the production of arteriosclerosis. This may
+play some part, but there are many other factors mostly unknown which
+determine in any case the production of arterial lesions.
+
+With every systole of the heart, blood is forced out into the arterial
+system against a certain amount of resistance represented by the
+tonicity of the capillary area, and the amount of cohesion between the
+viscous blood and the walls of arterioles. When a dilatation of the
+capillaries over any large area takes place, the blood pressure falls,
+provided there is no compensatory contraction in other areas to make up
+for the decreased resistance in the dilated vessels. The viscosity of
+the blood, as such, probably has very little effect on the resistance to
+the flow. With the systole of the heart there is a sudden dilatation of
+the arch of the aorta, and a wave of expansion follows, which is
+transmitted to the periphery and is lost only in the capillaries.
+
+The blood pressure is constantly changing. Physiologically there are
+relatively wide variations in the pressure in a perfectly normal
+individual. There are some persons who have hypotension, a blood
+pressure much below the normal. Such persons have usually small hearts,
+small aortas, and they seem to have but little resistance to disease.
+Many diseases, especially the prolonged fevers, diminish markedly the
+blood pressure. Whether the hypertension is the cause of the structural
+changes that are found in the walls of the vessels, or is the result of
+the diminished area of the arterial tree through which the same amount
+of blood has to be driven as before the vessel walls became narrowed, is
+still disputed. As has been stated, experimental evidence would tend to
+place the initial blame upon the poisons circulating in the blood, which
+first damage the vessel walls. The subsequent changes then produce
+thickening and inelasticity. Some think (Allbutt) that the hypertension
+is primary. There are cases seen clinically that lend support to this
+view and there is experimental evidence also (v. Chap. II). Not
+infrequently individuals in middle life begin to show increase of
+arterial blood pressure without discoverable cause. In such case it may
+be that there is slowly progressing chronic nephritis. The urine if
+examined only superficially in single specimens may not reveal any
+abnormalities. Careful functional examination by means of the newer
+tests may reveal functional deficiency. It must not be supposed that
+all cases of increasing hypertension are cases of chronic nephritis. The
+opinion has already been expressed (Chap. III) concerning this point.
+Experience has convinced me that the opinion expressed in former
+editions is not altogether correct.
+
+
+=Age=
+
+No age is exempt from the lesions of arteriosclerosis if we consider the
+two groups. However, the disease is seen for the most part in persons
+past middle life. The relative frequency with which it is found in the
+different decades depends on so many factors that it is of no value to
+tabulate them. As has been stated, arteriosclerosis of all types is an
+involution process that advances with age. Longevity is a question of
+the integrity of the arterial tissue, and no one can tell what sort of
+"vital rubber" (Osler) any one of us has. However, many with poor tubing
+may make such use of it that it will outlast good tubing that is badly
+treated. Unfortunately we have no way of telling early enough with just
+what sort of arterial tissue we are starting life.
+
+
+=Sex=
+
+There is no doubt that men are far more prone to arterial disease than
+women are; all statistics are in accord on this point. This is explained
+by the greater exposure of men to those conditions of life which tend to
+produce circulatory strain, and so to produce arteriosclerosis, or vice
+versa. Arteriosclerosis in women is not often seen until after the
+fiftieth year. Cases of the most extreme grade of pipe stem arteries
+are, however, seen in old women, and calcified arteries are not hard to
+find among the inmates of an old woman's home.
+
+
+=Race=
+
+Some of the most beautiful examples of arteriosclerosis in this country
+are seen in the negro. Not only is this disease more frequent in the
+black race, but the age of onset is much earlier than in the Caucasian.
+The accidents of arteriosclerosis, viz., aneurysm, cerebral hemorrhage,
+etc., are more common among the negro males. The etiologic factors that
+are most often found in the history are the prevalence of syphilis and
+hard physical labor.
+
+
+=Occupation=
+
+Certain occupations have a distinct causal relationship to
+arteriosclerosis; among such are particularly those entailing prolonged
+muscular exercise, especially if much lifting is necessary. Every one is
+familiar with the phenomena accompanying the exertion of lifting. The
+breath is drawn in, the glottis is closed, and the muscles of the chest
+wall are held rigidly while the exertion lasts. This causes a great
+increase in blood pressure, and constant repetition of this will produce
+permanent high tension. In hospitals, the stevedores as a class have
+marked arteriosclerosis, and, almost without exception, they are
+comparatively young men. Occupations that are accompanied with prolonged
+mental strain, such as now occur to the heads of large manufacturing and
+financial institutions, also predispose to early arterial changes.
+Psychic activity, especially when it is accompanied by worry, is a
+potent factor in the production of the increased blood pressure which is
+the chief factor in producing arterial disease. It has been suggested
+that sexual continence in high-strung men produces changes in the
+nervous system which can conceivably lead to the production of high
+tension and further to arteriosclerosis. This, however, I can not think
+has any foundation in fact except in so far as such men are prone to
+live at high speed and wear themselves out sooner than the normal
+person. The sexual continence _per se_ is not harmful. There are,
+however, men who seem not to be harmed by the constant wear and tear of
+our modern life. These are the exceptions.
+
+Workers in factories where paint is made and the ingredients
+hand-mixed, are prone to develop arteriosclerosis early in life. It has
+been found that the laborers most apt to be victims of lead intoxication
+are those who are careless in their habits of cleanliness, particularly
+in regard to the fingernails. The continuous absorption of lead into the
+system, brings about a condition of hypertension that has its inevitable
+results.
+
+The fact is that any occupation which entails either the absorption of
+toxic substances, or prolonged muscular labor, will hasten markedly the
+onset of arterial disease.
+
+
+=Food Poisons=
+
+The opinion that arteriosclerosis is due in large part to poisoning by
+end products or by-products of protein digestion is now receiving much
+support. Experiments on dogs and rabbits have lent some confirmation to
+chemical observations. It has been shown that dogs fed for a long time
+on putrefied meat developed inflammation and degeneration of the
+adventitia and media, with hyperplasia and calcification of the intima
+of many arteries. In the pulmonary and carotid arteries, in the vena
+cavas and myocardium, there were extensive necroses and hyaline
+degeneration. Moreover, injections of sodium urate and ergot caused
+necroses in the muscularis and elastica of the aorta, pulmonary artery,
+vena cavas inferior and heart muscle, but there was no calcification.
+Guinea pigs which were fed indol in small doses by the mouth over a long
+period showed atheromatous degeneration of the aorta.
+
+
+=Infectious Diseases=
+
+As more study has been given to the arteries in persons who have died of
+the acute infectious diseases, more has come to light concerning the
+effects of the toxins of these diseases on the vessel walls. In the
+arteries of children who have died of measles, scarlet fever,
+diphtheria, cerebrospinal meningitis, etc., degenerative changes in the
+arteries occur, modified only by the length of time that the toxins have
+acted.
+
+Thayer has shown that the arteries of those who have passed through an
+attack of moderately severe or severe typhoid fever are as a rule more
+readily palpable than are the vessels of persons of corresponding years
+who have never had the disease. Clinically the typhoid toxin appears to
+cause the early production of arteriosclerosis. The changes in the
+arteries occur for the most part, and always earlier, in the peripheral
+arteries, and the media is chiefly affected. Minute yellowish patches
+are found on the aorta, carotids, and coronaries. In persons who have
+passed through an attack of one of the fevers, and have later died from
+some other cause, regenerative changes are sometimes found to have taken
+place in the arteries, consisting of an ingrowth of elastic fibers from
+the intact adventitia to the diseased media.
+
+That there are some other factors than the infectious disease which are
+concerned in the production of arterial changes seems evident from a
+study[14] made recently among a group of almshouse inmates ranging in
+age from 38 to 90 years. The study included 500 persons of both sexes.
+Careful histories were taken to determine the presence of antecedent
+infectious disease. The radial artery was palpated to determine the
+presence of sclerosis. Among the cases giving a history of one
+infectious disease the following table gives the results:
+
+ -------------------------------------------------------------
+ DISEASE NO. + ++ +++ POSITIVE NEGATIVE
+ -------------------------------------------------------------
+ Measles 47 10 6 12 28 19
+ Infectious arthritis 38 9 6 4 19 19
+ Pneumonia 30 5 8 5 18 12
+ Typhoid 27 6 8 3 17 10
+ Scarlet fever 10 0 0 4 4 6
+ Smallpox 14 1 4 0 5 9
+ Miscellaneous 12 2 5 2 9 3
+ -------------------------------------------------------------
+ 178 33 37 30 100 78
+ -------------------------------------------------------------
+
+ [14] Warfield, L. M.: Jour. Lab. and Clin. Med., November, 1917.
+
+A summary of the cases showed: 252 cases without sclerosis; 248 with
+sclerosis; 147 cases with infections but no sclerosis; 180 cases with
+infections and sclerosis.
+
+This study failed to throw any positive light on the question.
+Infectious diseases undoubtedly play a certain rôle, particularly those
+continuing a long time and certain particular infectious diseases, as
+measles.
+
+
+=Syphilis=
+
+Syphilis is one of the most important of the etiologic factors in the
+production of arteriosclerosis. It has been shown that in 85 per cent of
+cases of aortic insufficiency in persons, usually males, over forty-five
+years, who did not have chronic infective endocarditis, the Wassermann
+reaction was positive. Acute aortitis affecting the ascending and
+transverse portions of the arch of the aorta is very commonly seen, and
+the irregular, scattered, slightly raised, yellowish-white patches of
+sclerosis in the arch which are found years after the syphilitic lesion,
+are considered by some to be very characteristic of syphilis.
+Mesaortitis is the primary lesion and acts as a _locus minoris
+resistentiæ_ where an aneurysm forms.
+
+Hypertensive cardiovascular cases have been serologically studied, and a
+positive Wassermann reaction found in a large percentage of one series.
+In fifty cases, 90 per cent either gave a positive Wassermann reaction
+or luetin test, were known to have syphilis, or had children with
+hereditary syphilis. This suggests what might be called "familial
+cardiovascular syphilis."
+
+Hypertensive disease is possibly one of the common so-called "late"
+manifestations of syphilis. That syphilis is responsible for the
+arterial disease in the vessels of the brain, resulting in apoplexy or
+sudden cardiac death in middle life, has long been known. In fact, it is
+claimed (Osler) that all aneurysms occurring in persons under thirty
+years of age are due to syphilitic aortitis. In the late stages of
+syphilis the arterial lesions may be of a diffuse character.
+
+
+=Chronic Drug Intoxications=
+
+Lead, tobacco, and according to some, tea and coffee, are to be classed
+as causal factors in the production of arteriosclerosis. Certain it is
+that all these substances have a tendency to raise the arterial
+pressure, but whether the drug itself causes first a degeneration, and
+later a hypertension results, or vice versa, is not yet positively
+known. We have just mentioned that lead particularly has a marked effect
+in producing arterial lesions. Other drugs as adrenalin, barium
+chloride, physostigmin, etc., while producing experimental
+arteriosclerosis, hardly could produce the disease in man. =Alcohol= has
+been blamed for much, and as an etiologic factor in the production of
+arteriosclerosis formerly was accorded a first place. More recently much
+doubt has been thrown on this supposition by the work of Cabot, who
+showed that the mere drinking of even large quantities of spirits had no
+effect in producing arterial disease.
+
+This observation has been recently substantiated by Hultgen, who
+carefully studied clinically 460 cases of chronic alcoholism. He says,
+"There are no cardiovascular symptoms which might be termed
+characteristic of chronic alcoholism, unless it be the peculiar fetal
+qualities of the heart sounds which we know as embryocardia. I find this
+very frequent among drinkers, but I can offer only a tentative
+explanation for it, namely the following: Embryocardia can only occur
+with low tension blood pressure, and in the absence of renal
+insufficiency. Hence it might be considered as a useful condition of no
+pathologic significance at all. That alcohol is a sclerogenic pharmakon
+and productive of arteriosclerosis with its usual train of symptoms may
+be a fact, but its demonstration would be difficult and is really not
+shown by my tabulations. There were cardiovascular changes, such as
+myocarditis, aortitis, valvular heart disease and arteriosclerosis in
+chronic alcoholics in 54.3 per cent of 461 cases, but this by no means
+constitutes a proof of the causal relationship between these lesions and
+the abuse of liquors. I believe it, nevertheless, to be good reasoning
+to ascribe the bulk of cardiovascular symptoms to the sclerogenic action
+of alcohol, while abstaining from an interpretation of its
+pathogenesis." Just what rôle =tobacco= plays is difficult to say. My
+own opinion is, that of itself when used in moderation, it has no ill
+effects. However, as tobacco is a drug that may raise the blood
+pressure, excessive use must be held responsible for the production of
+arteriosclerosis. It is difficult to separate its effects from those
+produced by eating and drinking.
+
+
+=Overeating=
+
+There can be no doubt but that the constant overloading of the stomach
+with rich or difficultly digestible food is responsible for a large
+number of cases of arteriosclerosis. Every one must have noted the
+increase in force and volume of the heart beat after the ingestion of a
+large meal. The constant repetition of such processes conceivably can
+lead to damage to the vessel walls through hypertension.
+
+In the metabolism of food in the intestines there are substances
+produced which are poisonous when absorbed directly into the
+circulation. Ordinarily these substances are rendered harmless either
+before absorption or are detoxicated in the liver to harmless
+substances. It is conceivable that a constant overproduction of such
+poisons would eventually damage the defensive mechanism of the body to
+such an extent that some of the poisons would circulate in the blood. An
+expression of a surplus of one, at least, of these decomposition
+products is the appearance of indican in the urine. It is not believed
+that indicanuria has the importance attached to it which some authors
+would have us believe. It is found too often and in too many varying
+conditions, nevertheless it undoubtedly does reveal the presence of
+perverted metabolism.
+
+In how far the toxins absorbed from the intestinal tract are responsible
+for the production of arterial disease, it is not possible to say. Some
+observers lay great stress on this factor as a cause of
+arteriosclerosis. The author believes that the rôle played by the
+absorption of products of perverted intestinal metabolism is an
+important one. The primary change is an increased tension in the
+arterioles which later leads to thickening of the coats of the vessels
+and to the other consequences of arterial disease. A vicious circle is
+thus established which has a tendency to become progressively worse.
+
+
+=Mental Strain=
+
+More and more does one become impressed with the fact that patients with
+arteriosclerosis are very often those who take life too seriously and
+either from ambition or from an exalted sense of duty lead especially
+strenuous lives. Not always are these persons addicted to drug or liquor
+habit. Many are rather abstemious in their habits. It is not so often
+that we see as a victim of arteriosclerosis, the carefree person who
+laughs his way through life without worrying about the morrow. He is not
+so prone to arteriosclerosis. Worry is a far more potent cause of
+breakdown than actual manual work. It is the rule to find thickened
+arteries among neurasthenics. This may be only part of a generalized
+degeneration of all tissue in the body. The blood pressure in such
+persons is usually low. So many men of our better class live under a
+continuous mental strain in the business world. The increase in
+arteriosclerosis cases is real, not apparent. The intense mental strain
+seems to cause a marked increase in blood pressure (for short periods of
+mental effort this has been proved) over a period of time sufficient to
+cause permanent changes in the vessel walls. The same sequence of events
+repeats itself; high tension, arterial strain, compensatory thickening,
+hypertrophied heart, etc.
+
+Certainly the character of the arterial tissue has much to do with the
+determination of degenerative changes which may result from the action
+of one or more of the etiologic factors.
+
+
+=Muscular Overwork=
+
+Muscular overwork is to be reckoned with as an etiologic factor. One
+sees it especially among the laboring class in both whites and negroes.
+Possibly other factors, as alcohol and coarse heavy food, contribute to
+the early arterial degeneration. Hypertrophy of the heart occurs in
+athletes, and statistics gathered among the oarsmen especially, show a
+relatively high mortality at the different decades traceable to the high
+tension produced while in training. This question deserves more
+consideration than has been accorded it.
+
+
+=Renal Disease=
+
+Chronic disease of the kidneys (contracted red kidney) is one of the
+most certain producers of hypertension; in fact, some maintain that high
+tension, even without demonstrable kidney lesions, as revealed by
+careful urine examinations, is a valuable sign pointing to chronic
+nephritis. This is doubted by others, myself among them. Just what
+causes the increase in blood pressure sometimes to over 270 mm. of Hg,
+is not definitely known. It seems most probable that it is some poison
+elaborated by the diseased kidneys and absorbed into the general
+circulation. There it acts primarily on the musculature of the
+arterioles causing tonic contraction and an increase of work on the part
+of the heart to force the blood through narrowed channels. One fact is
+certain. We see patients in coma due to renal disease with blood
+pressure much over 200 mm of Hg. As these cases clear up, the pressure
+may fall, and should they seemingly recover, the recovery is accompanied
+with a marked decrease in blood pressure, finally reaching the normal
+for the individual. Moreover, in the course of a severe acute or
+subacute nephritis, hypertension is associated with headache, partial or
+total blindness, and drowsiness. When the pressure is reduced, all these
+symptoms disappear.
+
+There is also the chronically shrunken and scarred kidney known
+pathologically as the arteriosclerotic kidney. It is probable that there
+are two groups of cases which we may designate: (1) primary; (2)
+secondary. In the primary group the kidney disease antedates the
+sclerosis of the arteries, and the sclerosis is most probably dependent
+on the constant high tension. We know that prolonged hypertension will
+produce severe forms of arteriosclerosis. The arterial disease in this
+group is caused by the renal disease.
+
+In the second group the kidney changes are apparently due to the general
+arteriosclerosis which, affecting the kidney vessels, causes changes
+leading to atrophy and subsequent fibrous tissue ingrowth of scattered
+areas. These cases are not necessarily associated with hypertension; on
+the contrary there is more apt to be hypotension. Where the first group
+occurs for the most part in young and active middle-aged people, the
+second group is the result of involutionary processes which accompany
+advanced age.
+
+However careful a urinalysis may be, there is no assurance that one can
+predict the pathologic state of the kidney. Often so-called normal urine
+will be secreted by a badly diseased kidney, whereas a urine which
+contains considerable albumin and many casts may be secreted by a kidney
+which is only temporarily the seat of inflammation. What matters after
+all is not the state of the kidney which the pathologist describes, but
+the actual functional response of the kidney in the body to the various
+tests now well known.
+
+
+=Ductless Glands=
+
+At the present time the tendency among some writers is to make the
+ductless glands the responsible agents in almost all diseases.
+Arteriosclerosis is no exception to this tendency. Sajous, for example,
+divides the morbid process producing arteriosclerosis into three types;
+(1) autolytic, (2) adrenal, (3) denutrition. In the first type he finds
+the pancreas to be the most important gland. It supplies an internal
+secretion which "takes a direct part in the protein metabolism of the
+tissue cells, and also in the defensive reactions within these cells, as
+well as in the phagocytes and in the blood stream." This being the case
+exaggeration of this digestive process has tissue destruction as its
+result, arteriosclerosis among them.
+
+In the adrenal type Sajous argues that adrenalin produces lesions
+experimentally, therefore the adrenal gland has a profound influence by
+its internal secretion in connection with the sympathetic system in
+producing degenerations leading to arteriosclerosis.
+
+The denutrition type has as its particular gland the thyroid. The
+sclerotic process in the arteries is due to the lack of thyroid as in
+cases of myxedema. After a long résumé of his ideas he concludes "that
+arteriosclerosis is the result of excessive or deficient activity of
+certain ductless glands, the thyroid and adrenal in particular."
+
+No one can dogmatically deny the part which the ductless glands may play
+in the production of arteriosclerosis, but it hardly seems that there is
+enough actual experimental evidence to show that they take such an
+important part as Sajous believes. Until further and more convincing
+evidence is offered by competent investigators, I prefer to look with
+some skepticism upon the ductless gland theory of the causation of
+arteriosclerosis. The field lends itself too easily to speculation and
+imagery. Some are already allowing themselves the mental debauch of this
+nature.
+
+
+
+
+CHAPTER VII
+
+THE PHYSICAL EXAMINATION OF THE HEART AND ARTERIES
+
+
+=Heart Boundaries=
+
+In order to be able to estimate the departures from normal in the
+boundaries of the heart, it is essential that there be a definite
+appreciation of the boundaries of the normal heart in relation to the
+chest wall.
+
+It is frequently stated that the right limit of cardiac dullness is
+normally, in the adult, just at the right border of the sternum. This is
+not strictly accurate. Careful dissections at the autopsy table and
+x-ray plates of the chest made at a distance of two meters from the tube
+show that the border of the right auricle is from one to one and a half
+and even two centimeters from the edge of the sternum at the level of
+the fourth rib, and on the living subject this can be also demonstrated.
+The right border of the heart usually is from 3 to 4 cm. from the
+midsternal line at the level of the fourth rib.
+
+Again there is a term used in defining the apex, known as the point of
+maximum impulse. As this does not always coincide with the apex beat and
+with the outer lower left border of the heart, it would be better to use
+the term apex beat.
+
+Normally, then, the cardiac dullness, the so-called relative cardiac
+dullness, begins above at the upper border of the third costal
+cartilage, as a rule, and taking a somewhat curved line with the
+concavity inward, descends to the fifth interspace or beneath the fifth
+rib from 9 to 10 cm. from a line drawn through the center of the sternum
+parallel to its length, the midsternal line. This seems to me to be a
+better method of recording the size of the heart than by the lines
+commonly used; viz., the nipple, or midclavicular, or parasternal line.
+Below, the cardiac dullness is merged into the tympany from the stomach
+and the dullness from the liver. At the sixth right costosternal
+articulation there is a sharp turn upwards forming at that point with
+the liver the cardiohepatic angle. At the fourth right cartilage or the
+third interspace, the dullness is from one to two centimeters from the
+edge of the sternum. We have then a somewhat pear-shaped area or
+triangular area with the apex at the apex of the heart. The so-called
+absolute cardiac dullness does not appear to me to be of any great
+significance. In reality it is the limit of lung resonance and may be
+greater or less, not so much on account of variations in the size of the
+heart, as of variations in size of the lungs and shape of the chest
+wall.
+
+The really crucial question which should always be asked is, Is the
+heart enlarged or decreased in size? The position of the apex beat alone
+can not determine this, neither can the limit to the right of the
+sternum. The distance between these two points and the depth of the
+dullness at a distance of 5 cm. from the midsternal line on the left
+side, will give the size of the heart as nearly as can be obtained in
+the living subject. A series of measurements in normal adults average 13
+to 14 cm. and 9 to 10 cm. respectively. For women they are about 1 cm.
+less in each direction.
+
+The elaborate mechanism known as the orthodiagraph is probably the best
+means of determining the actual limits of the heart, but few men have
+such an expensive instrument, and, moreover, at the bedside such an
+instrument could not be used. From comparative measurements I concur in
+the belief of those who affirm that careful percussion will furnish
+equally as accurate limits.
+
+The first step in making an examination of the heart is to expose the
+patient's chest in a good light, and, sitting at his right side,
+carefully inspect the chest. The position of the apex beat, heaving,
+bulging, retraction of interspaces, etc., can easily be seen if
+visible. After careful inspection has given all the data which it is
+possible to obtain, one next lays the palm of the hand over the heart
+and attempts to palpate the apex beat. The thrust of the apex in a
+hypertrophied heart can readily be felt, and one can feel whether the
+heart is regular, irregular, intermittent, or has other change in
+rhythm. The shock of the closing valves, particularly the aortic, can be
+felt, and that and the forcible apical impulse are very suggestive signs
+of hypertrophy and hypertension. Thrills may also be felt and can be
+timed in relation to the heart cycle.
+
+
+=Percussion=
+
+It is to percussion that we next proceed, and for the data in regard to
+the size of the heart, it is, for our purpose, the most valuable of all
+the physical methods of heart examination.
+
+First and foremost we wish by percussion to learn the actual size of the
+heart, in other words what is ordinarily called the relative cardiac
+dullness. With the absolute dullness we are not concerned. That
+irregular area represents, as has been said, actually the =limits of
+lung resonance=. The heart may or may not be covered with lung; there
+may or may not be the incisura cardiaca. What I wish to insist upon is
+that the size of the area of absolute dullness can give us no data in
+regard to the size of the heart. What we must endeavor to learn is the
+actual size of the heart as nearly as our crude means will permit.
+
+Light, very light, almost inaudible percussion, what Goldscheider called
+"Schwellungsperkussion," must be practiced. Use the middle finger of the
+right (left) hand as the hammer and the last joint of the middle finger
+of the left (right) hand pressed firmly against the chest, as
+pleximeter. I believe it is better to place the pleximeter finger
+parallel to the boundary to be limited although some place the finger
+perpendicularly, that is, pointing toward the boundary. Now and then it
+helps to bend the pleximeter finger at the second joint, hold it
+perpendicularly to the chest wall, and strike the joint directly in line
+of the finger. This in my hands has been of great assistance in
+percussing the limits of the heart dullness. Pottenger's "light touch
+palpation" is a modification of the light palpation and, to my mind, has
+no very special advantages. Auscultatory percussion is of great value at
+times. The bell of the stethoscope is placed over the portion of heart
+uncovered by lung (should such be the case), and with this point as a
+center the chest is lightly and quickly tapped along radii converging
+toward the stethoscope. One soon learns to recognize the change of pitch
+as the tapping reaches the border of the heart. It is well to use all
+methods, especially in difficult cases, and to compare the results.
+Personally I have found that by light percussion I can limit with much
+accuracy the upper, right, and left borders of the heart.
+
+There is much to be gained by using light percussion. Strong blows set
+in vibration not only the underlying structures, but also more or less
+of the chest wall. We wish to avoid this source of error, we do not wish
+to differentiate by pitch alone. Finally one's pleximeter finger
+becomes, after long practice, so sensitive to changes in the resonance
+of structures lying below it, that there is actual feeling of impairment
+to the slightest degree. This delicate touch is what we should endeavor
+to cultivate.
+
+It is at times of advantage to use immediate percussion. This is done by
+bending the fingers of the striking hand, bringing the tips in a line
+and striking the chest lightly with the four fingers as one finger. Some
+find it easier to percuss the dullness due to the heart in this way than
+by mediate percussion.
+
+The little hammer and hard rubber, celluloid, bone, or ivory pleximeter
+does not seem to me to be nearly as good as the fingers. Moreover, one
+always has his hands, but may forget his hammer and pleximeter.
+
+
+=Auscultation=
+
+In auscultating the heart I prefer the binaural stethoscope of the Ford
+pattern. The recent substitution of an aluminum bell for the hard rubber
+bell is an improvement. Personally I do not favor the phonendoscope or
+any of the new patent non-roaring instruments now for sale by urgent
+instrument makers. The phonendoscope has its uses, for example in
+auscultating the back when a patient is lying in bed or in listening to
+the heart sounds when a patient is under an anesthetic; but for
+differentiating the murmurs and for heart diagnosis, I much prefer the
+regular bell stethoscope.
+
+In arteriosclerosis the two places over which it is important to listen
+are the apex and the second right cartilage, the aortic area. Over the
+former, one gains data in regard to the strength of the heart as
+indicated by the first sound, over the latter point, one learns of the
+tension in the aorta by the character of the sound produced when the
+aortic valves close.
+
+The hypertrophy of the heart in arteriosclerosis is invariably due to
+the enlargement and thickening of the left ventricle. From the nature of
+the position which the heart assumes in the thorax, this enlargement is
+downward and to the left. The apex beat will therefore be found in the
+fifth or sixth interspace, and definitely at an increased distance from
+the midsternal line. As stated above, it is most important that this
+distance be accurately measured and put down in the notes of the case
+for future reference. No satisfactory prognosis can be given unless this
+is done, for the gradual increase or the decrease under treatment in the
+size of the heart can thus be definitely known, and, knowing the other
+factors, a prognosis may be given which will be of some value to the
+patient.
+
+
+=The Examination of the Arteries=
+
+It is exceedingly difficult at times to affirm definitely that an
+artery, the radial for example, is actually sclerosed. Much depends on
+the sensitiveness of the fingers of him who palpates, and much upon the
+relation of the palpated artery to the surrounding, chiefly underlying,
+structures. In the examination of arteries it is well to inspect the
+body for the pulsations caused by them. Frequently an exceedingly
+tortuous artery, such as the brachial, may be seen throughout its whole
+extent and yet the radial appear little, if any, thickened by palpation.
+Again the artery of a pulse of high tension which is small in size but
+full between the beats, may not be as sclerosed as one which collapses
+and feels much softer. It is difficult to obtain accurate data in regard
+to the tension in an artery by feeling it with the fingers of one hand.
+One should use both hands. With the middle finger of the right (left)
+hand the artery is compressed peripherally, that is, nearest the wrist.
+The blood is then pressed out of the artery with the middle finger of
+the left (right) hand, so as to obliterate completely the pulse wave and
+the two or three inches between the middle fingers are felt with the
+index fingers. By holding the finger firmly on the artery near the wrist
+so as to block any wave that may come through the palmar arch by
+anastomosis with the ulnar artery and by releasing pressure on the
+proximal middle finger, some idea may be had of the degree of pulse
+tension. However, no amount of practice can more than approximate the
+tension and when one is surest that he can tell how many millimeters of
+pressure there are, he is apt to be farthest wrong when he checks his
+guess with the sphygmomanometer.
+
+Much may be learned from carefully palpating the peripheral arteries,
+and, as a rule, the sclerosis of these arteries means general
+arteriosclerosis, although there are many exceptions to this.
+
+A more recent method, and one which in the author's hands has been found
+to be valuable, is that proposed by Wertheim-Salomonson who palpates the
+artery not with the ball of the finger but with the fingernail. The
+finger is held so that the nail is perpendicular to the surface of the
+skin and the artery is felt with the end of the nail. The sensation is
+perceived at the root and makes use of all the sensitive nerve endings
+there. In this way it is possible to feel the arterial wall distinctly,
+and a little practice will enable one to determine whether or not the
+vessel wall is thickened. It is also possible to determine with a
+considerable degree of accuracy the diameter of the artery and the size
+of the wall when the current is cut off by pressure on the proximal side
+of the artery. It is best to have a firm background when this
+"fingernail" palpation is used. This may be obtained by palpating the
+radial artery against the lower end of the radius.
+
+Probably the best method of palpating the arteries, especially the
+radial, to determine the degree of sclerosis and thickening, is to use
+the tip of the finger and roll it carefully over the artery. The tip of
+the finger is exceedingly sensitive and, moreover, it is a firmer
+palpating surface than the ball, thus enabling one to appreciate degrees
+of sclerosis which could not be differentiated by palpation with the
+soft yielding ball. This finger tip palpation is well illustrated in the
+figures here shown. (Figs. 57 and 58.)
+
+[Illustration: Fig. 57.--A method of finger-tip palpation of the radial
+artery. (Graves.)]
+
+[Illustration: Fig. 58.--Another method of finger-tip palpation of the
+radial artery. (Graves.)]
+
+
+=Estimation of Blood Pressure=
+
+It must be borne in mind at the outset that arteriosclerosis and high
+blood pressure are not always associated. As a matter of fact in the
+severest grades of senile arteriosclerosis the blood pressure is usually
+below the normal for the individual's years. However, as high tension is
+a frequent factor in the production of arterial thickening, blood
+pressure readings are of importance.
+
+The instrument which one uses is of minor importance provided it is
+properly standardized. The most important feature of the instrument is
+the cuff. This must be 12 cm. wide and be long enough to wrap around the
+arm several times so that the pressure is evenly distributed over the
+whole arm and not over a small portion. One mercury instrument we had in
+the hospital was reported to be at great variance with a dial
+instrument. This mercury instrument was provided with a cuff which was
+short and was tied around the arm by means of a piece of tape. This
+caused a tight constriction over a small area and rendered the
+estimation too high. A new, long tailed cuff easily remedied the
+apparent defect in the instrument.
+
+In taking blood pressures the difference from day to day of 10 or even
+15 mm. of systolic pressure has no great significance. Fluctuations of
+the systolic pressure alone, it is insisted upon, have very little
+meaning. One must take the whole pressure picture into consideration and
+determine how the picture changes in order to draw any conclusion in
+regard to the state of the blood pressure. Failure to pay attention to
+this evident point has caused much futile work to be written and
+published.
+
+It is well to emphasize again the point that the blood pressure picture
+consists of the systolic, the diastolic, the pulse pressure and the
+pulse rate.
+
+
+=Palpation=
+
+Hoover has called attention to the direct palpation of the femoral
+artery just below Poupart's ligament as a more accurate index of the
+pressure in the aorta than the palpation of the radial artery. Possibly
+one can obtain a more accurate estimate of the blood pressure in this
+way. This, however, is open to dispute. To estimate the blood pressure
+by palpating the radial artery is most deceptive. In about 75 per cent
+of cases one can tell fairly well whether the pressure is abnormally
+high or abnormally low. Small variations are impossible to determine.
+Unquestionably it is most advantageous to get into the habit of
+palpating the femoral artery and checking the result with the
+sphygmomanometer so that the fingers may be trained to appreciate as
+accurately as possible changes of pressure.
+
+It may be that one day when the instrument is needed it is not at hand.
+A well-trained touch then becomes a great asset.
+
+
+=Precautions When Estimating Blood Pressure=
+
+There are certain precautions which must be strictly observed when
+deductions are drawn from the manometer readings. The psychic factor
+must be reckoned with. Any emotion may cause marked variations in the
+pressure. Excitement and anger are especial sources of error. Even the
+slight excitement arising from taking the first blood pressure on a
+nervous patient especially is apt to give false values. Usually the
+readings must be taken many times at the first sitting and the first few
+may have to be set aside. Worry is a potent factor in raising the
+pressure. A walk to the physician's office, especially if rapid, has its
+effect.
+
+The position of the patient when the blood pressure is taken is
+important. Usually in the office the pressure is taken when the patient
+sits in a chair. He should assume a relaxed, comfortable attitude. The
+readings should be made at the same time of day and at the same interval
+between meals. The pressure in both arms should be measured and
+comparisons should be made only between readings on the same arm. These
+precautions may seem useless and even somewhat trivial, and the
+conditions difficult to control. But unless they are carefully observed
+the readings will be false, no comparisons can be drawn between the
+readings on different days, and the instrument will most probably be
+blamed. I have known this to happen so often that I can not emphasize
+too strongly the importance of controlling all the essential conditions
+which go to make accurate work.
+
+
+=The Value of Blood Pressure=
+
+In the past few years there has been a veritable avalanche of blood
+pressure instrument salesmen who have covered the country, sold
+instruments, and have made many startling claims for the instrument.
+They have emphasized its value out of proportion to what the instrument
+can do even in the hands of one familiar will all the defects.
+Consequently it is not necessary to emphasize the value of blood
+pressure. It seems best to utter a few words of caution in regard to its
+interpretation.
+
+The value lies not in the occasional estimation compared with some other
+one reading, but in the frequent estimation and in the visualization of
+the blood pressure picture. For the great majority of diseases the blood
+pressure has no particular value except to show that the circulation is
+not materially disturbed. The limits of normal are rather wide, so that
+consideration of the patient's age, sex, build, etc., will give us some
+idea of a base line, so to speak, for any one person. Wide departures
+from relatively normal figures are important, but are not diagnostic or,
+rather, pathognomonic. I can not help but feel that the diastolic
+pressure is _the_ most important part of the blood pressure picture.
+Persistent high diastolic pressure means increased work for the heart,
+which, if acting for a long time against the high peripheral resistance,
+must eventually hypertrophy. The arteries become thickened, lose their
+wonderful elasticity, fibrous tissue is deposited in their walls, and
+the vicious circle is established which leads to pathologic
+hypertension.
+
+Blood pressure readings must be intimately mixed with brains in order to
+be of any great value in diagnosis or prognosis.
+
+
+
+
+CHAPTER VIII
+
+SYMPTOMS AND PHYSICAL SIGNS
+
+
+=General=
+
+Well developed arteriosclerosis shows four pathognomonic signs: (1)
+hypertrophy of the heart; (2) accentuation of the aortic second sound;
+(3) palpable thickening of the arteries; and (4) heightened blood
+pressure. However, it must not be inferred that these signs must be
+present in order to diagnose arteriosclerosis. It has already been said
+that a very marked degree of thickening, with even calcification of the
+palpable arteries, may occur with absolutely no increase of blood
+pressure, and at autopsy a small flabby heart may be found.
+
+While arteriosclerosis is usually a disease which is of slow maturation,
+nevertheless cases are occasionally seen which develop rather rapidly.
+The peripheral arteries have been noticed to become stiff and hard in as
+relatively brief a time as two years from the recognized onset of the
+disease.
+
+Since involution processes are physiologic, as has been described (vide
+infra), arteriosclerosis may assume an advanced grade and run its course
+devoid of symptoms referable to diseased arteries. It is doubtful
+whether the sclerosis itself could produce symptoms, except in cases
+later to be described, were it not that the organs supplied by the
+diseased arteries suffer from an insufficient blood supply and the
+symptoms then become a part of the symptom-complex of any or all the
+affected organs.
+
+There are cases, however, in comparatively young persons where a
+combination of certain ill-defined symptoms gives a clue to the
+underlying pathologic processes. These symptoms of early
+arteriosclerosis are the result of slight and variable disturbances in
+the circulation of the various organs. Normally there are frequent
+changes in the blood pressure in the organs, but the vasomotor control
+of normal elastic vessels is so perfect that no symptoms are noted by
+the individual. When the arteries are sclerosed, they are less elastic
+and the blood supply is, therefore, less easily regulated. At times
+symptoms occur only after effort. The patient may tire more readily than
+he should for a given amount of mental or bodily exercise; he is weary
+and depressed, and occasionally there is noted an unusual intolerance of
+alcohol or tobacco. Vertigo is common, especially on rising in the
+morning or in suddenly changing from a sitting to a standing position.
+Some complain of constant roaring or ringing in the ears. There may be
+dull headache that the accurate fitting of glasses does not alleviate.
+Unusual irritability or somnolency with a disinclination to commence a
+new task may be present. Sometimes the effort of concentrating the
+attention is sufficient to increase the headache. This has been called
+"the sign of the painful thought." Numbness and tingling in the hands,
+feet, arms, or legs are also complained of, and neuralgias, not
+following the course of the nerves but of the arteries, also occur. It
+is important to remember that the train of symptoms resembling
+neurasthenia in a person over forty-five years old may be due to
+incipient arteriosclerosis. This tardy neurasthenia frequently
+accompanies cancer, tuberculosis, diabetes, and incipient general
+paralysis, as well as incipient arteriosclerosis.
+
+Bleeding from the nose, epistaxis, taking place frequently in a
+middle-aged person, sometimes is an early symptom. The bleeding may be
+profuse, but is rarely so large as to be positively harmful. In fact, it
+may do much good in relieving tension. Slight edema of the ankles and
+legs is seen. Dyspnea on slight exertion is not uncommon. Dyspeptic
+symptoms are not infrequent, pyrosis (heartburn), a feeling of fullness
+after meals with belching or a feeling of weight in the epigastrium.
+The dyspeptic symptoms may be so marked that one might almost speak of a
+variety of arteriosclerosis, the dyspeptic type. For quite a while
+before any symptoms that would definitely fix the case as one of
+undoubted arteriosclerosis, the patient complains that foods which
+previously were digested with no difficulty now give him gastric
+distress. The examination of the stomach contents of a patient
+presenting gastric symptoms reveals usually a subacidity. The total
+acidity measured after the Ewald test meal may be only 20 and the free
+HCl may be absent. Attention has been called to an unnatural pallor of
+the face in early arteriosclerosis. Progressive emaciation is sometimes
+seen in cases of arteriosclerosis and may be the only symptom of which
+the patient complains.
+
+
+=Hypertension=
+
+Not all cases of arteriosclerosis are accompanied by increased arterial
+tension. As has been stated in a previous chapter, the blood pressure in
+the arterial system depends chiefly on two factors; viz., the degree of
+peripheral (capillary) resistance, and the force of the ventricular
+contraction. The highest arterial pressures recorded with the
+sphygmomanometer occur not in pure arteriosclerosis but in cases where
+there is concomitant chronic interstitial disease of the kidneys. When
+this is found there is always arteriosclerosis more or less marked. In
+cases where the arteries are so sclerosed that they feel like pipe stems
+there may be an actual decrease in the blood pressure. Hence the
+clinical measuring of the pressure in the brachial artery alone is not
+sufficient for a diagnosis of arteriosclerosis. A persistent high blood
+pressure even with normal urinary findings is not a sign of
+arteriosclerosis. The high tension later may lead to the production of
+sclerosis of the arteries, but in these cases the kidney may be
+primarily at fault.
+
+The impression must not be gained that hypertension in itself always
+constitutes a disease or even a symptom of disease. Hypertension itself
+is practically always a compensatory process. That is to say, it is the
+attempt on the part of the body to equalize the distribution of blood in
+the body when there is some poison causing constriction of the small
+arteries. In this sense hypertension is not only essential, but actually
+life-saving. A heart which is so diseased that it can not respond to the
+call for increased action by hypertrophy of its fibers, would shortly
+wear out. The very fact that the heart becomes enlarged and the tension
+in the arteries becomes high, indicates that in such a heart there was
+great reserve power. But while hypertension is largely an effort at
+adjustment among the various parts of the circulation, it nevertheless
+tends to increase, provided the cause or causes which produced it act
+continuously. Moreover, as has been said (Chap. II), the arterioles do
+not respond to increased work on the part of the heart by expanding, but
+by contracting. A vicious circle is thus maintained which eventually
+must lead to serious consequences.
+
+Hypertension is then, if anything, only a symptom which may or may not
+demand treatment. That hypertension leads to the production of sclerosis
+of the arteries has been repeatedly affirmed here. In certain cases it
+is good and should not be experimented with. In other cases it is bad
+and some treatment to reduce the tension must be tried. The main point
+is to regard hypertension as one regards a compensated heart lesion.
+
+Prof. T. Clifford Allbutt divides the causes of arteriosclerosis
+clinically into three classes: (1) The toxic class--the results of
+poisons of the most part of extrinsic origin, chiefly those of certain
+infections. In some of these diseases, the blood pressures, as for
+example, in syphilis, are ordinarily unaffected; in others, as in lead
+poisoning, they are raised. (2) The class he calls hyperpietic,[15] in
+which an arteriosclerosis is the consequence of tensile strength, of
+excessive arterial blood pressure persisting for some years. A
+considerable example of this class is the arteriosclerosis of granular
+kidney, but in many cases kidney disease is, clinically speaking,
+absent. (3) The involutionary class, in which the change depends upon a
+senile, or quasisenile degradation. This may be no more than wear and
+tear, a disposition of all or of certain tissues to premature
+failure--partly atrophic, partly mechanical--under ordinary stresses; or
+it also may be toxic, a slow poisoning by the "faltering rheums of age."
+In ordinary cases of this class the blood pressures for the age of the
+patient are not excessive. Although the toxins of the specific fevers,
+notably typhoid, as stated above, and influenza, have been shown to
+produce arteriosclerosis, this, under favorable circumstances he
+believes tends to disappear. This has been shown by Wiesel.
+
+ [15] From piesô to squeeze, oppress or distress. Hyperpiesis,
+ therefore, signifies excessive pressure.
+
+As the blood pressure is dependent on the resistance offered by the
+capillaries and arterioles, there are only two ways in which increased
+pressure can be brought about; either by rendering the blood more
+viscous, or by the generation of some poison from the food taken into
+the body which, acting on the vasomotor center or directly on the finer
+vessels, arteriolar or capillary, sets up a constriction over any large
+area, and mainly in the splanchnic area. In regard to the liability to
+arteriosclerosis, this area stands second only to the aortic and
+coronary areas. He believes that arteriosclerosis itself has little
+effect in raising arterial pressure. Many cases are seen in which with
+extreme arteriosclerosis there was no rise in blood pressure, and some
+in which pressures have been rising even long before the appearance of
+arterial disease. Prof. Allbutt also believes that in the hyperpietic
+cases the arteries undergo a transient thickening, which can be removed
+if the causes can be reached and overcome.
+
+Clinically speaking, then, hyperpietic arteriosclerosis is not a
+disease, but a mechanical result of disease. If the narrowing of the
+arterioles is brought about by thickening due to arteriosclerosis, then
+it would seem _a priori_ that such obliteration should cause a rise in
+pressure. Were the vascular system a mere mechanical set of tubes and a
+pump, this would happen, but other factors of great importance must be
+taken into consideration besides the mechanical factors; viz., chemical
+and biological factors. Thus, whole parts may be closed and with
+compensatory dilatation in other parts there would be little or no
+change in pressure, unless there were hyperpiesis. In established
+hyperpiesis, we note two conditions in the radial artery: first, a
+comparatively straight vessel with a small diameter; secondly, a larger,
+more tortuous vessel, "the large leathery artery." In the cases of the
+first group, hyperpiesis is often more marked, although not appearing so
+to the examining finger, than in the second class. In view of the
+difficulty of estimating by touch alone the amount of hyperpiesis in a
+contracted hard artery, it is often overlooked until a ruptured vessel
+in the brain startles us to a realization of our mistake. The "narrow"
+artery is more dangerous than the tortuous one, for with every change in
+pressure the passive vessels of the brain must receive blood that under
+normal conditions would go to other parts of the circulation.
+
+In involutionary sclerosis there is a gradual thickening and tortuosity
+of the vessel, which although it may be greater than in the hyperpietic
+cases, yet is never so dangerous to life. The heart in hyperpiesis
+hypertrophies and dilates, but such a heart is the result, not an
+integral part, of the arterial disease.
+
+
+=The Heart=
+
+When the arterial tree becomes narrowed and the resistance offered to
+the flow of blood thereby is increased, more muscular work is required
+of the left ventricle and according to the general laws which govern
+muscles the ventricle hypertrophies. There is an actual increase in
+number of fibers as well as an increase in the size of the individual
+fibers. Some of the best examples of simple hypertrophy of the left
+ventricle are found under such circumstances. The chambers as a rule do
+not dilate until the resistance becomes greater than the contraction can
+overcome, when symptoms of broken compensation of the heart take place.
+The hypertrophy of the left ventricle brings more of this portion of the
+heart toward the anterior chest wall. The enlargement is toward the
+left, also, consequently the apex-beat is found below and to the left of
+its usual site, even an inch or more beyond the nipple line. The impulse
+is heaving, pushing the palpating hand forcibly up from the chest wall.
+The visible area of pulsation may occupy three interspaces and the
+precordium is seen to heave with every systole. On auscultation the
+second sound at the aortic cartilage is ringing, clear, and accentuated.
+Not infrequently, too, the first sound is loud and booming, but has a
+curious muffled sound that may even be of a murmurish quality. The
+leaflets of the mitral valve may be the seat of sclerosis, the edges are
+slightly thickened and do not quite approximate, thus causing a definite
+murmur with every systole. This murmur may be transmitted out into the
+axilla and be heard at the inferior angle of the left scapula.
+
+
+=Palpable Arteries=
+
+Not every artery that can be felt is the subject of arteriosclerosis,
+and, as has been stated, palpable arteries being more or less a
+condition of advancing years, judgment as to whether the artery is
+pathologically or physiologically thickened may be a matter of
+individual opinion. A radial artery that lies close to the lower end of
+the radius and can actually be seen to pulsate when the hand is held
+slightly extended on the back of the wrist, is easily felt, but must
+not, therefore, be considered a sclerosed artery. The radial may be so
+deeply situated in the wrist of a fat subject that it is difficultly
+palpable. Yet the two cases just described may have arteries of
+identical structure, there being no more retrogressive changes in the
+one than in the other. "Experience is fallacious and judgment
+difficult."
+
+The small, contracted, wiry artery of a chronic nephritic may feel like
+a pipe stem, but if properly felt the mistake will not be made of
+considering such an artery an unusually sclerosed one. When the wave is
+pressed out of such a high tension artery, it is found that what seemed
+to be a firm sclerosed vessel, was in reality an artery tightly
+stretched over the column of blood.
+
+
+=Ocular Signs and Symptoms=
+
+It would not exaggerate too much to say that the examination of the eye
+grounds with the ophthalmoscope is the most important aid in the early
+diagnosis of arteriosclerosis. Long before there are any subjective
+symptoms, changes can be seen in the blood vessels of the retina which,
+while not always diagnostic, at least call attention to a beginning
+chronic disease. As I become more proficient in the use of the
+ophthalmoscope, I am impressed with the importance of the ocular signs
+of arterial disease. I would urge practitioners to familiarize
+themselves with this instrument. The electrically lighted instruments on
+the market now have so simplified the technic that any physician should
+be able to see the grosser changes which take place in the arteries and
+veins of the retina and in the disc. Frequently the ophthalmologist is
+the first to recognize early arteriosclerosis. In the fundus are seen
+increased tortuosity of the retinal vessels and their terminal twigs
+with more or less bending of the vessels at their crossings. The
+arteries are terminal ones, and small patches of retinitis are therefore
+found. The changes have been divided into (1) suggestive, (2)
+pathognomonic.
+
+Under (1) are:
+
+(a) Uneven caliber of the vessels,
+
+(b) Undue tortuosity,
+
+(c) Increased distinctness of the central light streak,
+
+(d) An unusually light color of the breadth of the artery.
+
+Under (2) are:
+
+(a) Changes in size and breadth of the retinal arteries so that they
+look beaded,
+
+(b) Distinct loss of translucency,
+
+(c) Alternate contractions and dilatations in the veins,
+
+(d) Most important of all, the indentation of the veins by the stiffened
+arteries.
+
+There is yet another sign which appears to be pathognomonic. The
+arteries are pale, appear rigid and through the center, parallel to the
+course, is a rather bright, fine threadlike line. The appearance is
+known as the "silverwire" artery. It is particularly constant in
+hypertension where the most beautiful examples are seen.
+
+Moreover, there is the arcus senilis, the fine translucent to opaque
+circle surrounding the outer portion of the iris. Practically every one
+with a well-marked arcus senilis has arteriosclerosis, but vice versa
+not every one with even marked arteriosclerosis has an arcus senilis.
+
+In general, the symptoms are gradual loss of acute vision, and attacks
+of transient loss of vision. The explanation which has been offered for
+these phenomena is the contraction in a diseased central artery.
+
+
+=Nervous Symptoms=
+
+The onset of arteriosclerosis is, in the majority of cases, so insidious
+that certain nervous manifestations, due in all probability to
+disturbances in blood pressure, are present long before the actual
+sclerosis of the arteries can be felt. These nervous symptoms are at
+times the sign posts to show us the way to accurate diagnosis. There may
+be gradual increase in irritability of temper, inability to sleep,
+vertigo even extending to transient attacks of unconsciousness. Loss of
+memory for details frequently is an early symptom of sclerosis of the
+cerebral arteries. Nervous indigestion may be present. Various
+paresthesias as numbness, tingling, a sense of coldness or of heat or
+burning, a sense of stiffness or even actual stiffness or weakness may
+occur in the arms and legs, more frequently in the legs. The pain
+complained of may be due to occlusion of an artery, although evidence
+for this is lacking. It has been thought by some that the pain in angina
+pectoris might be due to this cause.
+
+Several curious and interesting diseases which have been thought by some
+to have arteriosclerosis as a basis are accompanied by pain. Such are
+erythromelalgia, Raynaud's disease, "dead fingers," and intermittent
+claudication.
+
+Erb has reported a large series of intermittent limp (claudication) from
+his private practice. He finds that the large majority of the cases
+occur in men. The abuse of tobacco was evidently the main etiologic
+factor in about half of the cases. Repeated exposure to cold and the
+abuse of alcohol were responsible for most of the other cases. Curiously
+enough he finds that a history of syphilis was present in only a small
+proportion of his cases. It is his firm conviction that intermittent
+limping--which he thinks should be called angiosclerotic dysbasia--is
+frequently incorrectly diagnosed. It is mistaken for other troubles and
+treated wrongly. As gangrene may develop this is particularly dangerous.
+The affection generally develops gradually, although he has seen cases
+where the onset was rather acute. The partial or complete lack of the
+pulse in the foot is the one striking sign, together with the varying
+behavior of the pulse, its disappearance when the feet are cold and its
+return after a warm foot bath or under other treatment. Signs of general
+arteriosclerosis were present in nearly every case. When there is a
+tendency to the development of intermittent limp he finds that a
+valuable sign is the manner in which the leg blanches when it is lifted
+repeatedly while the patient is recumbent and becomes hyperemic later
+when placed horizontally. In health this change occurs more rapidly.
+
+
+
+
+CHAPTER IX
+
+SYMPTOMS AND PHYSICAL SIGNS
+
+
+=Special=
+
+Our conception of arteriosclerosis as a degenerative process affecting
+the vascular tree rather than a disease, removes the possibility of
+discussing special symptoms. As a matter of fact, we know of very few
+organs where even profound pathologic changes in the vascular system
+produced during life any symptoms which could be laid to these arterial
+changes. Kind nature has given to us such an excess of organs of every
+kind that the destruction of large portions of any organ seems to affect
+the function but little. So only particular groups of organs, which show
+symptomatic changes as the result of arteriosclerotic processes, will be
+discussed. It is realized that this may not give Teutonic completeness
+to the discussion, but it certainly saves paper and has a distinct
+practical value to the long suffering reader.
+
+Although arteriosclerosis is a disease which affects the whole arterial
+system, it nevertheless never reaches the same grade all over the body.
+The difference in the structure and functions of the various organs
+determines to great extent the eventual symptomatology. Endarteritis
+obliterans of a small sized artery in the liver or leg would lead to no
+marked symptoms, as the circulation is so rich that the anastomoses of
+the blood vessels would soon establish a collateral circulation that
+would be perfectly competent to sustain the function of the part. Quite
+different would it be should one of the small arteries of the brain, the
+lenticulo-striate, for example, which supplies the corpus striatum,
+become the seat of a thrombosis or embolism caused by arteriosclerosis.
+The arteries of the brain are terminal arteries and the blood supply
+would be cut off entirely with a resulting anemic necrosis of the part
+supplied by the artery and a loss of function of the part. What would be
+of no moment in the leg or arm might prove even fatal in the brain.
+
+The further symptomatology, therefore, of arteriosclerosis depends
+entirely on the organ or organs most affected by the interference with
+the blood supply. The following groups may be recognized:
+
+ 1. Cardiac.
+
+ 2. Renal.
+
+ 3. Abdominal.
+
+ 4. Cerebral.
+
+ 5. Spinal.
+
+ 6. Local vasomotor effects.
+
+ 7. Pulmonary.
+
+
+=Cardiac=
+
+Most cases of arteriosclerosis sooner or later present symptoms
+referable to the heart. When the organ is hypertrophied and is already
+working against an enormous peripheral resistance, a slight excess of
+work put upon it may cause a dilatation of the chambers with the
+resulting broken compensation. There is dyspnea on slight exertion,
+possibly some precordial distress, slight edema of the ankles and lower
+legs and possibly scanty urine. With proper care, a patient with such
+symptoms may recover, but the danger of another break in compensation is
+enhanced. The next attack is more severe. The edema is greater, there
+may be signs of edema of the lungs, effusions into the serous cavities
+may occur. The heart shows marked dilatation. There is gallop or canter
+rhythm and there are loud murmurs at the apex. When a patient is first
+seen in this stage, it may be quite impossible to state whether or not
+there is true valvular disease of the heart. The muscle is usually
+diseased in that there is fibroid degeneration of more or less
+extensive character. This factor causes the heart to lose much of its
+elasticity and increases the tendency to permanent dilatation. Such
+cases must be watched before one can say that true valvular
+insufficiency is not present. The fatal termination of such a case is
+quite like that of true valvular disease. There is increasing dyspnea,
+increasing anasarca, and the patient usually succumbs to edema of the
+lungs, drowned in his own secretions.
+
+[Illustration: Fig. 59.--Aneurysm of the heart wall. (Milwaukee County
+Hospital.)]
+
+A very rare complication of the fibroid degeneration of the heart muscle
+is aneurysm of the heart wall. (Fig. 59.) The apex of the left
+ventricle is most commonly the site of the aneurysm and rupture
+occasionally occurs. Such an accident is rapidly fatal. In the
+arteriosclerotic process which occurs at the root of the aorta, the
+coronary arteries become involved both at the openings and along the
+courses of the vessels. A branch or branches or even one artery may
+become blocked as a result of obliterating endarteritis. The arteries of
+the heart are not terminal vessels but as a rule blocking of a large
+branch leads to anemic infarct. These areas become replaced by fibrous
+tissue which in the gross specimen appears as streaks of whitish or
+yellowish color in the musculature. Anemic infarcts may not occur. In
+such cases the anastomosis between branches of the coronary arteries is
+unusually free. Through arteriosclerosis of the coronary vessels
+extensive fibrous changes may occur that lead to a myocardial
+insufficiency with its attending symptoms--dyspnea, irregular and
+intermittent heart, gallop rhythm, edema, etc. One of the most
+distressing and dangerous results of sclerosis of the coronary arteries
+and of the root of the aorta is angina pectoris. While in almost every
+case of angina pectoris there is disease of the coronary arteries, the
+contrary does not hold true, for most extensive disease, even embolism,
+of the arteries is frequently found in persons who never suffered any
+attacks of pain. This symptom group is more common in males than in
+females and as a rule occurs only in adult life. "In men under
+thirty-five syphilitic aortitis is an important factor." (Osler.)
+
+Since the valuable experiments of Erlanger on heart block, considerable
+attention has been paid to lesions of the Y-shaped bundle of fibers, a
+bundle arising at the auriculoventricular node and extending to the two
+ventricles, known also as the auriculoventricular bundle of His.
+Interference with the transmission of impulses through this bundle gives
+rise to the symptom group known as the Stokes-Adams syndrome, which is
+characterized by: (a) slow pulse, (b) cerebral attacks--vertigo,
+syncope, transient apoplectiform and epileptiform seizures, (c) visible
+auricular impulses in the veins of the neck. Many of the cases which
+occur are in elderly people the subjects of arteriosclerosis.
+
+[Illustration: Fig. 60.--Large aneurysm of the aorta eroding the
+sternum. Death from rupture through the skin preceded by frequent small
+hemorrhages. (Milwaukee County Hospital.)]
+
+So far as we now know all cases of the Stokes-Adams syndrome are caused
+by heart block which is only another name for disease in the
+auriculoventricular bundle. Of interest here is the fact that besides
+gummata, ulcers, and other lesions of the bundle, definite
+arteriosclerotic changes have been found.
+
+"The investigation of a typical case of Stokes-Adams disease has shown
+that the symptoms of this case are caused by some lesion in the heart
+which gives rise to the condition now generally termed heart block.
+Practically all degrees of heart block have been observed, namely,
+complete heart block and partial block with 4:1, 3:1, and 2:1 rhythm,
+and occasionally ventricular silences. These stages occurred during
+recovery.
+
+"Experiments testing the reaction of the heart to various extrinsic
+influences demonstrate that when the block is complete the ventricles do
+not respond to influences presumably of vagus origin, although the
+auricles still respond normally to such influences, that effects exerted
+upon the heart presumably through the accelerators still influence the
+rate of the ventricles as well as that of the auricles.
+
+"When the block is partial the rate of the ventricular contraction
+varies proportionally with the rate of the auricular contractions but
+only within certain limits. When these limits are exceeded the block
+becomes more complete, i. e., a 2:1 rhythm may be changed into a 3:1
+rhythm, this into a 4:1 rhythm, and this into complete block, and vice
+versa.
+
+"The syncopal attacks are, in all probability, directly dependent upon a
+marked reduction of the ventricular rate. Such reductions of the
+ventricular rate are always associated with an increase of the auricular
+rate, and it is believed that the latter is the cause of the former."
+(Erlanger.)
+
+The epileptiform seizures of the syndrome may be caused by the anemia of
+the brain resulting from failure of the heart to supply a sufficient
+quantity of blood.
+
+The apoplectiform attacks are most probably caused by venous congestion
+when the slowing of the ventricular contractions is not sufficient to
+cause convulsions, but will just cause complete unconsciousness.
+
+
+=Renal=
+
+Chronic nephritis, hypertension, arteriosclerosis form a most important
+trinity. Some stoutly affirm that in all cases of high tension there is
+chronic renal disease. Certainly the very highest blood pressures which
+we see occur in the chronic interstitial forms of kidney disease. The
+cause is most probably to be sought in some poison which is elaborated
+in the kidney, is absorbed into the circulation and acts powerfully
+either on the vasoconstrictor center as a stimulus, or directly on the
+musculature of the small arteries all over the body. Usually
+hypertension is progressive but it may be temporary.
+
+A man, 43 years old, entered the Milwaukee County Hospital in uremic
+coma. The systolic blood pressure was 280-290 mm. Hg, the diastolic
+pressure 220 mm. (Janeway instrument). Under treatment his blood
+pressure gradually became lower, at the same period the albumin and
+casts gradually disappeared from the urine. In two weeks from admission
+he seemed perfectly well, there were no albumin or casts found in the
+urine, and the systolic blood pressure was 136 mm., not a high figure
+for a muscular man of the laboring class. It must be admitted, however,
+that such cases are the exception, not the rule.
+
+Patients suffering from the association of chronic nephritis with
+hypertension die slowly, usually. There is gradual development of
+anasarca. Headache is frequent and severe. Pains all over the body may
+occur. The sight may suddenly become dim or may even be lost. Dizziness
+may be complained of and dyspnea is usually marked. Cyanosis comes on,
+the pulse becomes weak, irregular or intermittent, heart failure sets
+in, and the patient dies with edema of the lungs.
+
+Another class of renal arteriosclerosis is characterized by a small
+granular kidney in which fibrous changes of a patchy character have
+taken place. These scattered areas are the result of obliterating
+endarteritis of renal arteries here and there with consequent anemia,
+death of cells, and replacement by fibrous tissue. It occurs as part of
+a generalized arteriosclerosis in which the whole arterial system is the
+seat of diffuse (senile) sclerosis. The palpable arteries are usually
+beaded or even encircled with calcareous deposits and the aorta is the
+seat of an extensive nodular and ulcerating sclerosis. The heart is
+usually small, shows extensive fibrous and fatty changes and possibly
+the condition known as "brown atrophy;" the blood pressure is low. Such
+cases do not show any special symptoms. They are anemic, short of breath
+on exertion, have the appearance and show the signs of senility.
+
+In the first group it is, at times, difficult to say whether the kidney
+disease or the arterial disease is the most important. From a clinical
+standpoint the decision is not essential as the end results are much the
+same in both. However, when actual uremic symptoms dominate the picture,
+it becomes evident that the disease of the kidney is the chief feature
+in the causation of the symptoms.
+
+
+=Abdominal or Visceral=
+
+There is an important group of cases to which but little attention has
+been paid until quite recently. This is the abdominal or visceral type
+of arteriosclerosis. It has been stated that arteriosclerosis of the
+splanchnic vessels almost invariably causes high tension. Among others,
+Janeway has shown that general arteriosclerosis without marked disease
+of the splanchnic vessels does not cause as a rule increase of blood
+pressure.
+
+There are cases in which the brunt of the lesion falls upon the
+abdominal vessels. Such cases have been called "angina abdominalis." It
+has been suggested (Harlow Brooks) that this type of arteriosclerosis
+may be determined by constant overloading of the stomach with food,
+especially rich and spiced food. This causes overwork of the special
+arteries connected with digestion and so leads to sclerosis of the
+vessels of the stomach, pancreas, and intestines. Personal habits
+probably influence to great extent the production of this more or less
+=localized= condition.
+
+The organs supplied by the diseased arteries suffer from changes
+analogous to those occurring in general or local malnutrition, such as
+starvation, old age, or local anemias. These changes are atrophy with
+hemachromatosis (brown atrophy) or fatty infiltration and degeneration.
+Following the degenerative changes there result connective tissue growth
+and further limitation of the functionating power of the affected
+organs.
+
+Pain is a more or less constant symptom of visceral sclerosis. In the
+early stages there may be only a sense of oppression, of weight, or of
+actual pressure in the abdomen or pit of the stomach. There may be only
+recurring attacks of violent abdominal pain accompanied by vomiting. In
+some cases symptoms of tenderness in the epigastrium, pains in the
+stomach after eating, vomiting and backache may suggest gastric ulcer.
+There may be dyspnea and a sense of anguish accompanied with a rapid and
+feeble pulse. Hematemesis may make the symptom group even more like
+ulcer of the stomach, and only the course of the disease with the
+failure of rigid ulcer treatment and the substitution of treatment
+directed toward relief of the arterial spasm with resulting betterment,
+enables one to make a diagnosis. The condition may be present for years
+and the symptoms only epigastric tenderness with dizziness and sweating
+on lying down after dinner, as in one of Perutz's patients. The attacks
+are probably due to spasmodic contraction of the sclerosed intestinal
+vessels with a resulting local rise in blood pressure. The pains are
+most probably due to the spasm of the intestinal muscles, and some think
+they are located in the sympathetic and mesenteric plexuses.
+
+This result of arteriosclerosis is not so uncommon, and by keeping this
+cause of obscure abdominal pain in mind we are now and then enabled to
+save a patient from operation.
+
+An autopsy on a case which for many years had attacks of abdominal pain
+and cramp-like attacks, with high blood pressure and heart hypertrophy,
+showed extensive sclerosis of the abdominal aorta, superior mesenteric
+and iliacs. These vessels were calcified. Hypertrophy of the left
+ventricle was found. The kidneys were microscopically normal. There were
+no changes in the ascending aorta but in the descending portion there
+were scattered nodules and small calcified plaques.
+
+The attacks of pain from which this patient suffered for many years, the
+hypertrophy of the left ventricle and the increased blood pressure were
+thought to be directly due to the sclerosis of the abdominal vessels.
+
+
+=Cerebral=
+
+It has been stated that arteriosclerosis is a general disease, yet
+certain systems of vessels may be affected far more than others, and
+indeed there may be marked sclerosis at one part of the body and none
+demonstrable at another part.
+
+In advanced sclerosis there may be one or more of a series of accidents
+due to embolism, thrombosis, or rupture of the vessels. Such conditions
+as transient hemiplegia, monoplegia or aphasia may occur. The attacks
+may come on suddenly and be over in a few minutes; what Allbutt calls
+"Larval apoplexies." They may last from a few hours up to a day, and are
+very characteristic. A patient aged 64 years with pipe stem radials and
+tortuous hard temporals would be lying quietly in bed when suddenly he
+would stiffen, the eyes would become fixed and the breathing cease. In a
+few seconds consciousness returned, the patient would shake himself,
+pass his hand over his brow and ask, "Where am I? Oh, yes, that's all
+right." He had as many as thirty of these attacks in twenty-four hours,
+none of them lasting over one minute. To just what such attacks are due,
+it is hard to say. Some have attributed them to spasm of the smaller
+blood vessels of the brain, but there have never been demonstrated in
+the vessels any constrictor fibers.
+
+There is a well recognized form of dementia caused by arteriosclerosis.
+In general paralysis of the insane and in senile dementia the blood
+vessels are always diseased. Milder grades of psychic disturbances are
+accompanied by such symptoms as mental fatigue, persistent headaches,
+vertigo, memory weakness and fainting. Aphasia, periods of excitement
+and mental confusion occur in some. Later stages are at times
+accompanied by inclination to fabulate, loss of judgment,
+disorientation, narrowing of the external interests, episodes of
+confusion and hallucinatory delirium.
+
+The hemiplegias, monoplegias and paraplegias may occur again and again
+and last for one or two days. Unless there has been rupture of the
+vessels, there is complete recovery as a rule.
+
+In persons who have arteriosclerosis with high tension attacks of
+melancholia are seen. There are at the same time fits of depression,
+insomnia, irritability, fretfulness, and a generally marked change in
+disposition. When the tension is reduced by appropriate treatment these
+symptoms disappear, to recur when the tension again becomes high. On the
+contrary, attacks of mania are accompanied by low blood pressure. The
+dizziness and vertigo in cerebral arteriosclerosis are probably due to
+the stiffness of the vessels which prevents them from following closely
+the variations of pressure produced by position, and thus, at times, the
+brain is deprived of blood and a transient anemia occurs.
+
+Arteriosclerosis of the cerebral vessels is always a serious condition.
+The greatest danger is from rupture of a blood vessel. Another of the
+dangers is gradual occlusion of the arteries bringing about necrosis
+with softening of the brain substance. The latter is more apt to be
+associated with psychic changes, dementia, etc.; the former, with
+hemiplegia. It is curious that a small branch of the Sylvian artery, the
+lenticulo-striate, which supplies the corpus striatum, should be the one
+which most frequently ruptures. Where the motor fibers from the whole
+cortex are gathered together in one compact bundle, a very small
+hemorrhage may and does cause very serious effects. A comparatively
+large hemorrhage in the silent area of the brain may cause few or no
+symptoms.
+
+
+=Spinal=
+
+It is conceivable that arteriosclerosis of the vessels of the spinal
+cord might cause symptoms which would be referred to the areas of the
+cord where the process was most advanced. The lesions would be scattered
+and consequently the symptoms might be protean in character.
+
+True epileptic convulsions dependent on arteriosclerotic changes are
+also seen and are not so uncommon.
+
+This is on the whole a rare condition, much less common than
+arteriosclerosis of the cerebral vessels. Collins and Zabriskie report
+the following typical case:
+
+ "H., a fireman, fifty-one years old, was in ordinary good health
+ until toward the end of 1902. At that time he noticed that his legs
+ were growing weak and that they tired easily. Later he complained of
+ a jerking sensation in different parts of the lower extremities and
+ at times of sharp pain, which might last from several minutes to two
+ or three hours. The legs were the seat of a heavy, unwieldy
+ sensation, but there was no numbness or other paresthesia. About the
+ same time he began to have difficulty in holding the urine, a
+ symptom which steadily increased in severity. These symptoms
+ continued until March, 1903, i. e., for three months, then he
+ awakened one morning to find that he was unable to stand or walk,
+ and the sphincters of the bowels and bladder relaxed. There was no
+ complaint of pain in the back or legs, no difficulty in moving the
+ arms, in swallowing or in speaking. He says he was able to tell when
+ his lower extremities were touched and he could feel the bed and
+ clothes. He was admitted to the City Hospital three weeks later and
+ the following record was made on April 21, 1903.
+
+ "The patient was a frail, emaciated man of medium height, who had
+ the appearance of being 55-60 years of age. He was unable to stand
+ or walk. When he was lying, he could flex the thigh and the legs
+ slowly and feebly. There was slight atrophy of the anterior and
+ inner muscles, more of the left than of the right side. The knee
+ jerks and ankle jerks were absent. Irritation of the soles caused
+ quite a typical Babinski phenomenon. The patient had fair strength
+ in the upper extremities, but the arms tired very soon, he said. The
+ grip was moderate and alike in each hand. The motility of the face,
+ head, and neck was not noticeably impaired. There was no difficulty
+ in swallowing, and articulation was not defective. Tactile
+ sensibility was slightly disordered in the lower extremities,
+ although he could feel contact of the finger, the point of a pin,
+ and the like. Sensibility was not so acute as normal; there was a
+ quantitative diminution. Sensory perception was not delayed. There
+ was a distinct zone of slight hyperesthesia about as wide as the
+ hand above the femoral trochanters. Above that, sensibility was
+ normal. There was no discernible impairment of thermal sensibility.
+ No part of the body was particularly tender on pressure. A bedsore
+ existed over the sacrum, and there was excoriation of the genitals
+ from constant dribbling of urine.
+
+ "Examination of the chest showed shallow respiratory movements. The
+ heart was regular, weak, there were no murmurs, the second sound was
+ accentuated. Examination of the abdomen showed that the liver and
+ spleen were palpable, but were not enlarged. The abdominal reflexes,
+ both upper and lower, were sluggish. The patient was slow of speech,
+ likewise apparently of thought. He did not seem to show an adequate
+ interest in his condition, still he was fully oriented and seemed to
+ have a fair memory. His mental reflex was slow. There were
+ indications in the peripheral blood vessels and heart of a moderate
+ degree of general arteriosclerosis. The peripheral vessels such as
+ the radial, were palpable, the walls thickened, the blood pressure
+ increased.
+
+ "The patient did not complain of pain while he was in the hospital,
+ a period of four weeks, nor was there any particular change in the
+ patient's symptoms, subjective and objective, during this time. His
+ mental state remained clear until forty-eight hours before death,
+ when he became sleepy, stuporous, and comatose, dying apparently of
+ cardiac weakness, which had set in simultaneously with the clouding
+ of consciousness."
+
+ At autopsy, except for a few small hemorrhages in the posterior
+ horns of the lower dorsal segments on the right side and a similar
+ condition of the left anterior horns, there was nothing noticed. On
+ microscopic examination, there was found widespread sclerosis of the
+ vessels of the cord to a marked degree with only slight thickening
+ of the vessels of the brain. There were secondary degenerations of
+ ascending and descending type particularly marked at the ninth
+ dorsal segment. They included portions of all the tracts, the
+ pyramidal tract as well. The symptoms in brief were: (1) weakness
+ and easily induced fatigue of the legs; (2) peculiar sensations in
+ the lower extremities, described as jerky, numbness, heaviness, and
+ occasionally sharp pain; (3) progressive incontinence of urine; (4)
+ progressive paraplegia.
+
+Since one of the chief manifestations of syphilis is sclerosis of the
+arteries, neurologic cases characterized by irregular symptoms and signs
+which can not be placed in any of the definite system disease groups,
+are possibly due to irregularly scattered areas of sclerosis throughout
+the spinal cord caused by obliterating arteritis. Such cases are not so
+very uncommon. Several have come under my observation. Further studies
+of the spinal cords of these cases at autopsy are necessary before a
+final opinion can be given as to their dependence on arteriosclerosis of
+the spinal vessels.
+
+
+=Local or Peripheral=
+
+When the arteriosclerosis in the peripheral arteries reaches a stage
+where endarteritis obliterans supervenes, there is usually no chance for
+a compensatory or collateral circulation to be established. The area
+supplied by the vessel undergoes dry gangrene. A portion of a toe or
+finger or a whole foot or hand may shrivel up. It is more common to see
+the spontaneous amputation take place in the lower extremities. The same
+effect may be produced by the plugging of a vessel with a thrombus.
+There may be much pain connected with the sudden blocking, whereas the
+gradual obliteration of the blood supply of a toe or foot is not as a
+rule at all painful. The condition is at times revealed more or less
+accidentally when a patient injures his toe or foot and discovers that
+there is no sensation in the part and that the wound instead of healing
+is inclined to grow larger.
+
+Other interesting vasomotor phenomena are frequently connected with
+arteriosclerosis. Such a one is the curious condition known as Raynaud's
+disease, a vascular disorder which is divided into three grades of
+intensity: (1) local syncope, (2) local asphyxia, (3) local or
+symmetrical gangrene. This is not the place to describe this condition
+except to say that the condition called "dead fingers" is the most
+characteristic feature of the first stage. Chilblains represent the
+mildest grade of the second stage. The parts are intensely congested and
+there may be excruciating pain. Any one who has ever had chilblains
+knows how painful they can be. The general health is not impaired as a
+rule, although the attacks are apt to come on when the person is run
+down. The third stage may vary from a very mild grade, with only small
+necrotic areas at the tips of the fingers, to extensive multiple
+gangrene.
+
+Another and very rare condition in which chronic endarteritis was the
+only constant finding is the disease described by S. Weir Mitchell and
+called by him erythromelalgia (red neuralgia). This is "A chronic
+disease in which a part or parts--usually one or more extremities--suffer
+with pain, flushing, and local fever, made far worse if the parts hang
+down." (Weir Mitchell.)
+
+Probably the most frequently seen result of arteriosclerosis in the leg
+arteries is the remarkable condition, first described by Charcot, known
+as intermittent claudication. Persons the subject of this disease are
+able to walk if they go slowly. If, however, any attempt be made to
+hurry the step, there results total disability accompanied at times by
+considerable cramp-like pain. The condition is much more prone to occur
+in men than in women, and Hebrews seem more frequently affected. The
+cause is most probably to be sought in the anemia which results from the
+narrowing of the channels through which the blood reaches the part. The
+stiff, much narrowed arteries allow sufficient blood to pass along for
+the nutrition of the part at rest or in quiet motion. Just as soon as
+more violent exercise is taken, calling for more blood, an ischemia of
+the part supervenes, for the stiff vessels can not accommodate
+themselves to changes in the necessary vascularity of the part. A rest
+brings about a gradual return of blood and the function of the part is
+restored. Pulsation may be totally absent in the dorsal arteries of the
+feet and when the legs are allowed to hang down there is apt to be deep
+congestion.
+
+In this connection a curious case reported by Parkes Weber will not be
+out of place. The patient, a male, aged 42 years, complained of
+cramp-like pains in the sole of the left foot and calf of the leg
+occurring after walking for a few minutes and obliging him to rest
+frequently. When the legs were allowed to hang over the side of the bed,
+the distal portion of the left foot became red and congested looking.
+No pulsation could be felt in the dorsal artery of the left foot or in
+the posterior tibial artery. There was no evidence of cardiovascular or
+other disease. An ulcer on the little toe had slowly healed, but
+cramp-like muscular pains still occurred on walking. The disease had
+lasted about five years without the appearance of gangrene.
+
+Weber calls this case one of arteritis obliterans with intermittent
+claudication.
+
+
+=Pulmonary Artery=
+
+In the symptomatology of sclerosis of the pulmonary artery the clinical
+signs and symptoms are mostly referable to the obliterating endarteritis
+of the smaller vessels, while the physical signs are more apt to reveal
+the involvement of the main trunk. A history of severe infection in the
+past is frequent, especially smallpox, and accompanying aortic sclerosis
+with insufficiency of the mitral valve or stenosis of this valve is the
+rule. Striking cyanosis is an early symptom, while there is little if
+any dyspnea and edema. Intermittent dyspragia is common. There seems to
+be no tendency to clubbed fingers. Repeated hemorrhages from the lungs
+without the formation of infarcts may occur. There is usually an area of
+dullness at the upper left margin of the sternum and nearby parts,
+sensitive to pressure and to percussion, and the heart dullness extends
+unusually far towards the right. The diagnosis of the right ventricular
+hypertrophy may be substantiated by a fluoroscopic examination.
+
+
+
+
+CHAPTER X
+
+DIAGNOSIS
+
+
+=Early Diagnosis=
+
+Arteriosclerosis is essentially a disease of middle life and old age. It
+is not unusual, however, to find evidences of the disease in persons in
+the third decade and even in the second decade. Hereditary influences
+play a most important rôle, syphilis and the abuse of alcohol in the
+family history are particularly momentous. The recognition of the early
+changes in the arteries among young persons depends largely upon how
+carefully these changes are looked for. The difference in the point of
+view of one man who finds many cases in the comparatively young, and
+another man who rarely finds such changes early in life, at times,
+depends upon the acuity of perception and observation and not upon the
+fact that one man has had a series of unusually young arteriosclerotic
+subjects. The diagnosis of arteriosclerosis may be so easily made that
+the tyro could not fail to make it. It is, however, the purpose of this
+volume to lay stress on the earliest possible diagnosis and, if
+possible, to point out how the diagnosis may be arrived at. It is
+obviously much to the advantage of the patient to know that certain
+changes are beginning in his arteries, which, if allowed to go on, will
+inevitably lead to one or more of the symptom groups described in the
+preceding chapters.
+
+The combination of (1) hypertrophied heart, (2) increased blood
+pressure, (3) palpable arteries, and (4) ringing, accentuated second
+sound at the aortic cartilage is, in reality, the picture of advanced
+arteriosclerosis. If the individual is in good condition much may be
+done by judicious advice and treatment to ward off complications and
+prolong life with a considerable degree of comfort. But we should not
+wait until such signs are found before making a diagnosis and
+instituting treatment. As in all forms of chronic disease the early
+diagnosis is all important.
+
+The history of the case is the first essential. Often a careful inquiry
+into the personal habits of a patient, with the record of all the
+preceding infectious diseases will give us valuable information and may
+be the means of directing the attention at once to the possible true
+condition. Particularly must we inquire into the family history of gout
+and rheumatism. An individual who comes of gouty stock is certainly more
+prone to arterial degeneration than one who can show a healthy heredity.
+Alcoholism in the family also is of importance because of the fact that
+the children of alcoholics start in life with a poor quality of tissue,
+and conditions that would not affect a man from healthy stock might
+cause early degeneration of arterial tissue in one of bad ancestry.
+
+What infectious diseases has the patient had? Even the exanthemata may
+cause degenerations in the arteries, but, as has been shown, such
+lesions probably heal completely with no resulting damage to the vessel.
+Should the patient have passed through a long siege of typhoid fever the
+problem is quite different. Here (vide supra) (Thayer), the palpable
+arteries do appear to be sclerosed permanently. Probably the length of
+time that the toxin has had a chance to act determines the permanent
+damage to the vessel wall. More potent than all other diseases to cause
+early arteriosclerosis is syphilis, and hence very careful inquiry
+should be made in regard to the possibility of infection with this
+virus. Not only the fact of actual infection but the duration and
+thoroughness of treatment are important matters for the physician to
+know.
+
+What is the patient's occupation? Has he been an athlete, particularly
+an oarsman? Has he been under any severe, prolonged, mental strain? Is
+he a laborer? If so, in what form of manual labor is he engaged? Such
+questions as these should never be overlooked, as they form the
+foundation stones of an accurate diagnosis, and early, accurate
+diagnosis, we repeat, is essential to successful therapy.
+
+We have called attention to the factor of sustained high pressure in the
+production of arteriosclerosis. Constant overstretching of the vessels
+leads to efforts of the body to increase the strength of the part or
+parts. The material which is used to strengthen the weakened walls has a
+higher elastic resistance than muscle and elastic tissue, but a lower
+limit of elasticity, and is none other than the familiar connective
+tissue. In athletes, laborers, brain workers who are under constant
+mental strain, and in those whose calling brings them into contact with
+such poisons as lead, there is every factor necessary for the production
+of high tension and consequently of arteriosclerosis.
+
+Another question in regard to personal habits is how much tobacco does
+the patient use and in what form does he use it? Our experience is that
+the cigar smoker is more prone to present the symptoms of
+arteriosclerosis than the cigarette smoker, the pipe smoker, or the one
+who chews the tobacco. A very irritable heart results not infrequently
+from cigarette smoking but such is almost always found in young men in
+whom the lesions of arteriosclerosis are exceedingly rare. The
+probabilities are that the arteriosclerosis in cigar smoking results
+from the slowly acting poison which causes a rapid heart rate with an
+increase of pressure.
+
+Last but not least, and perhaps the most important question is, has the
+patient been a heavy eater? This I believe to be a potent cause of
+splanchnic arteriosclerosis with the resulting indigestion, cramp-like
+attacks, high blood pressure, etc. In a joking manner we are accustomed
+to remark, "Overeating is the curse of the American people." There is,
+however, much truth in that sentence. Osler, than whom there is no
+keener observer, states that he is more and more impressed with the fact
+that overloading the stomach with rich or heavy or spiced foods is today
+one of the first causes of arterial degeneration. It stands to reason
+that this is true. We know that organs exposed constantly to hard work
+undergo hypertrophy, and that the blood tension in those organs is high.
+Blood tension is, after all, dependent on capillary resistance, and if
+the capillaries are distended with blood, the resistance is great. The
+digestive organs can be no exception to this rule. Increased work means
+an increase of blood. This inevitably causes distension of the
+capillaries with stretching of the arteries and consequent damage to the
+walls. Once arteriosclerosis is present a vicious circle is established.
+
+A man about forty-five consults us and says that he has noticed recently
+that he gets out of breath easily; in tying his shoes he experiences
+some dizziness. He finds that he has palpitation of the heart and
+possibly pain over the precordial region now and then. He notices also
+that he is irritable, that is, his family tell him he is, and he notices
+that things that formerly did not annoy him, now are almost hateful to
+him. On examination, one finds a palpable radial, a somewhat
+hypertrophied heart and slightly accentuated second aortic sound. The
+blood pressure may be high. The urine may or may not reveal any
+abnormalities. Not infrequently, although no albumin may be found, there
+are hyaline casts. Such a case of arteriosclerosis is evidently not to
+be regarded as early. Then the question arises, How are we to recognize
+early arteriosclerosis? I do not believe that the solution of this
+problem lies entirely in the hands of the physician. Some men are
+fortunate enough to come up for an examination for life insurance before
+an observant doctor who recognizes the palpable artery, makes out the
+beginning heart hypertrophy and the slightly accentuated second aortic
+sound. The patient will tell you that he never felt better in his life.
+He gets up at seven, works all day, plays golf, drinks his three to six
+whiskies, and is proud of his physical development. But the great mass
+of people are not fortunate from this standpoint. They do not seek the
+advice of the physician until they are stretched out in bed. They boast
+of the fact that for twenty years they have never had a doctor. One may
+well say that it is a problem how to reach such persons. It seems to me
+that there can be but one way to do this. The people must be taught that
+the duty of a physician is just as much to keep them in health as it is
+to bring them back to health when they are ill. To that end people
+should be taught that at least twice a year they should be carefully
+examined. I do not mean that the patient should present himself to the
+doctor and, after a few questions the doctor say cheerfully, "You are
+all right." The patient should be systematically examined. That means a
+removal of the clothing and examination on the bare skin. Such
+cooperation on the part of patient and doctor would save the patient
+years of active life and make of the doctor, what his position entitles
+him to be, the benefactor to the community. Too often careless work on
+the physician's part lulls the patient into a false sense of security
+and he wakes up too late to find that he has wasted months or years of
+life. Early diagnosis of arteriosclerosis is only possible in
+exceptional cases unless people present themselves to the physician with
+the thought in mind that he is the guardian of health as well as the
+healer.
+
+There are patients who go to the ophthalmologist for failing vision.
+Physically they feel quite well. They have been heavy eaters, hard
+workers, men and women who have been under great mental strain. On
+examination of the fundus of the eye there is found slight tortuosity of
+the vessels with possibly areas of degeneration in the retina. A careful
+physical examination will usually reveal the signs of arteriosclerosis
+elsewhere. We have mentioned frequently high tension as an early sign.
+This must be taken with somewhat of a reservation, for this reason: not
+infrequently a persistent high tension is the earliest sign of chronic
+nephritis. The arteries may be pipe stem in character and the heart
+small and flabby. However, if one watches for the palpably thickened
+superficial arteries (always bearing in mind the normal palpability as
+age advances) and the high tension, he can not go far wrong in his
+treatment whether the case is one of chronic nephritis or of
+arteriosclerosis.
+
+There is also this to bear in mind. Arteriosclerosis may be marked in
+some vessels and so slight in the peripheral vessels that it can not
+with certainty be made out. But when the radials are sclerosed, it is
+usually the case that similar changes exist in other parts. Then too,
+there may be marked changes at the root of the aorta leading to
+sclerosis of the coronary vessels alone, and the first intimation that
+the patient or any one else has that there is disease, may be an attack
+of angina pectoris. Except for symptoms on the part of the heart there
+is no way to make the diagnosis of sclerosis of the coronary arteries.
+
+
+=Differential Diagnosis=
+
+In arriving at a diagnosis, when the question is whether or not
+arteriosclerosis is the main etiologic factor, the most important fact
+to know is the age of the patient. Other points that have been dwelt on
+fully must of necessity also be borne in mind.
+
+Possibly the chief conditions that may be confused with some of the
+results of arteriosclerosis are pseudo angina pectoris which may be
+mistaken for true angina pectoris, and ulcer of the stomach,
+appendicitis (?) or other inflammatory abdominal condition which may be
+mistaken for angina abdominalis.
+
+Differential tables are sometimes of value in fixing the chief points of
+difference graphically.
+
+ =Pseudo angina pectoris=.
+
+ Etiology rather certain; hysteria, neurasthenia, toxic agents, and
+ reflex irritations.
+
+ No age is exempt. Usually in young people, chiefly females.
+
+ Paroxysms of pain occur spontaneously, are periodic and often
+ nocturnal.
+
+ Pain, while severe, is diffuse and sensation is of distension of
+ heart. No sense of real anguish.
+
+ Duration may be an hour or more.
+
+ Restlessness and emotional symptoms of causative conditions are
+ prominent.
+
+ Usually no increase in arterial tension.
+
+ Prognosis favorable.
+
+
+ =True angina pectoris=.
+
+ Etiology not certain but almost always associated with
+ arteriosclerosis of the coronary arteries and also aortic
+ regurgitation.
+
+ Age is important factor. Rare before forty, and males usually
+ affected.
+
+ Paroxysms brought on by overexertions or excessive mental emotion.
+ Rarely periodic.
+
+ Intense pain, radiating down arm; heart felt as in a vise. Sense of
+ anguish and impending dissolution.
+
+ Duration from few seconds to several minutes.
+
+ Silent and fixed attitude, rigidity rather than restlessness.
+
+ Arterial tension is as a rule increased.
+
+ Prognosis most unfavorable.
+
+In differentiating between ulcer of the stomach and angina abdominalis
+the following points may be of service:
+
+
+ =Ulcer=.
+
+ Occurs as a rule in young persons, more often females.
+
+ Pain of boring character increased by food and by certain positions
+ with food in stomach. Felt through to left of spine.
+
+ Occult blood found in stools.
+
+ Considerable anemia apt to be present.
+
+ Arterial tension usually low.
+
+
+ =Angina abdominalis=.
+
+ Only occurs in adults over forty who have been heavy eaters and
+ drinkers, mostly males.
+
+ Pain cramp-like, diffuse, although more localized in epigastrium.
+ Not necessarily any connection with food.
+
+ No occult blood in stools.
+
+ Anemia more often absent.
+
+ Arterial tension high. (Splanchnic sclerosis.)
+
+
+=Diseases in Which Arteriosclerosis Is Commonly Found=
+
+There are certain more or less chronic diseases in which
+arteriosclerosis is found either as a separate disease or as a result of
+the chronic disease itself, or the sclerosis may be the cause of the
+disease. As examples of the first class are diabetes mellitus and
+cirrhosis of the liver. As examples of the second class are chronic
+nephritis, gout, syphilis, and lead poisoning. Examples of the third
+class have already been fully described. Then certain rare diseases that
+have been briefly described in this chapter, viz.: Raynaud's disease and
+erythromelalgia are frequently associated with demonstrable
+arteriosclerosis.
+
+
+
+
+CHAPTER XI
+
+PROGNOSIS
+
+
+In a disease that presents as many vagaries as arteriosclerosis, it is
+not possible to give a certain prognosis. Unfortunately we do not as a
+rule see the arteriosclerotic until the disease is well advanced, or
+even after some of the more serious complications have taken place. By
+that time the condition is progressive, and while the prognosis is grave
+the individual may live a number of years.
+
+It is fortunate for the arteriosclerotic that mild grades of the disease
+are compatible with a fairly active life. The disease in this stage may
+become arrested and the patient may live many years. Not only in the
+mild grades is this possible. Even patients with advanced sclerosis may
+enjoy good health provided the organs have not been so damaged as to
+render them unfit to perform their functions. The frequency with which
+we see advanced arteriosclerosis at the postmortem table as an
+accidental discovery, attests the truth of the foregoing statement. Yet
+how often does it happen that individuals, apparently in the best of
+health, suddenly succumb to an asthmatic or uremic attack, an apoplexy,
+cessation of the heart beat, or a rupture of the heart due to
+arteriosclerosis!
+
+In order to arrive at an intelligent opinion in regard to prognosis
+certain factors must be taken into consideration, chief of which are:
+the seat of the sclerosis; the probable stage; the existing
+complications; and, last and most important, the patient himself. The
+whole man must be studied and even then our prognosis must be most
+guarded.
+
+It is much more dangerous for the patient when the process is in the
+ascending portion of the arch of the aorta than when it has attacked the
+peripheral arteries. Here, at the root of the aorta, are the openings of
+the coronary arteries and the arteries supplying the brain are close
+by. The coronary arteries here control the situation. When loud murmurs
+are heard at the aortic orifice and the heart is evidently diseased, it
+is useful to divide the endocarditis into two types, the
+arteriosclerotic and the endocarditic. The etiology of the former is
+sclerosis and the prognosis is grave because of the liability, nay the
+probability, that the orifices of the coronary arteries will become
+narrowed. The etiology of the second type is in most cases rheumatic
+fever or some other infectious disease, and the prognosis is far better
+than in the first type. True, the two may be combined. In such a case,
+the prognosis is entirely dependent upon the course of the
+arteriosclerosis.
+
+The involvement of the arteries in the kidneys is of considerable
+importance, for it is usually bilateral and widespread. As a rule, the
+disease makes but slow progress provided that the general condition of
+the patient is good, but at any time from a slight indiscretion or for
+no assignable cause, symptoms of renal insufficiency may appear and may
+rapidly prove fatal.
+
+It must not be thought that because the localization of the
+arteriosclerosis in the peripheral arteries is usually the most
+favorable condition that it is therefore devoid of ill effects. On the
+contrary, very serious, even fatal, results may be brought about by
+interference with the circulation with resultant extensive gangrene of
+the part supplied by the diseased arteries. The amputation of a portion
+of a leg, for instance, may relieve, to some extent, an overburdened
+heart and prove life-saving to the patient, but the neuritic pains are
+not necessarily relieved. The torture from these pains may be
+excruciating.
+
+No stage of the disease is exempt from its particular danger. In the
+early stages of the disease before the artery or arteries have had time
+to become strengthened by proliferation of the connective tissue, there
+is the danger of aneurysm. Later, the very same protective mechanism
+leads to stiffening and narrowing of the arteries and hence to
+increased work on the part of the heart with all of its consequences.
+Thrombosis is favored, and where atheromatous ulcers are formed,
+embolism is to be feared.
+
+As the complications and results of arteriosclerosis come to the front
+every one must be considered by itself and as if it were the true
+disease. There may be a slight apoplectic attack from which the patient
+fully recovers, but the prognosis is now of a grave character, as the
+chances are that another attack may supervene and carry off the subject.
+Yet, after an apoplectic attack, patients have lived for many years.
+Probably the most noted illustration of this is the life of Pasteur. He
+had at forty-six hemiplegia with gradual onset. He recovered with a
+resulting slight limp, did some of his best work after the stroke, and
+lived to be seventy-three years old. Yet the exception but proves the
+rule and the prognosis after one apoplectic stroke should always be
+guarded.
+
+The first attack of cardiac asthma is to be looked upon as the beginning
+of the end. The end may be postponed for some time, but it comes nearer
+with every subsequent attack. One may recover from what appears to be a
+fatal attack of cardiac asthma accompanied by edema of the lungs and
+irregular, intermittent, laboring heart, but the recovery is slow and
+the chances that the next attack will be the fatal one are increased.
+
+The significance of albuminuria is difficult to determine. The kidneys
+secrete albumin under so many conditions that the mere presence of
+albumin in the urine may have but little prognostic value. Many cases
+are seen where there is no demonstrable albumin, and yet the patient may
+suddenly have a cerebral hemorrhage. As a general rule the urine should
+be carefully examined, but not too much stress should be laid on the
+discovery of albumin and casts. It is not always possible to determine
+the extent of the kidney lesion by the urinary examination, yet at any
+time a uremic attack may appear and prove fatal.
+
+After all the most important fact for the patient is not what the
+pathologist finds in his kidneys after he is dead, but what the living
+functional capacity of the kidneys is. This can now be determined in a
+variety of ways as the result of extensive work carried out in quite
+recent years. The simplest method of determining the functional capacity
+of the kidneys is by the injection into the muscles of the back of a
+solution containing 6 mg. of the drug phenolsulphonephthalein in one
+c.c. of fluid. This comes already prepared in ampules, with full
+directions for its employment.[16] Some clinicians use indigo-carmine in
+place of phthalein. The general consensus of opinion is in favor of
+phthalein.
+
+ [16] I have found the small colorimeter made by Hynson, Westcott and
+ Dunning, Baltimore, Mo., costing $5.00, a very practical instrument.
+
+The nephritic test meal carefully worked out by Mosenthal[17] gives much
+valuable information. The determination of the nonprotein nitrogen or
+the creatinin in the blood also reveals the functional capacity of the
+kidneys.[18]
+
+ [17] Mosenthal, H. O.: Arch. Int. Med., 1915, xvi, 733.
+
+ [18] Myers and Lough: Arch. Int. Med., 1915, xvi, 536.
+
+One might say that the appearance of albumin in the urine of an
+arteriosclerotic where it had not been before, is a bad sign, and in
+making a prognosis this must be taken into consideration.
+
+Bleeding from the nose is not infrequently seen in those who have
+arteriosclerosis. It can hardly be called a dangerous symptom as it can
+always be controlled by tampons. There are times when epistaxis is
+decidedly beneficial as it relieves headache, dizziness, and may avert
+the danger of a hemorrhage into the brain substance. It is rare to have
+nose bleed except in cases of high tension in plethoric individuals. My
+experience has been that it has saved me the trouble of bleeding the
+patient. It is always of serious import in that it indicates a high
+degree of tension, but there is scarcely ever any immediate danger from
+the nose bleed itself.
+
+Intestinal hemorrhage is always a grave sign. As has been shown,
+arteriosclerosis of the splanchnic vessels not infrequently occurs, and
+an embolus or thrombus may completely occlude the superior mesenteric
+artery. The chances of the establishment of a collateral circulation are
+small, as the arteries of the intestines are end arteries. Necrosis of
+the part follows, blood is found in the stools, and perforation or
+gangrene, or both, are apt to follow. There may be blocking of small
+branches only, leading to ulceration of the intestine. Under all
+conditions the prognosis is serious.
+
+The general condition of the patient, his build, physical strength,
+powers of recuperation, etc., must be taken into account in giving a
+prognosis. The more powerful the individual, the more favorable, as a
+rule, is the prognosis, with this reservation always in mind, that the
+greater the body development, the greater is the heart hypertrophy, and
+the accidents from high tension must not be overlooked. Many puny
+individuals with stiff, calcified arteries go about with more ease than
+a robust man with thickened arteries only. The differentiation as
+pointed out by Allbutt (page 186), is well to keep in mind in giving a
+prognosis. It can not be too strongly emphasized that it is the whole
+patient that we must consider and not any one system that at the time
+happens to be the seat of greatest trouble, and by its group of symptoms
+dominates the picture.
+
+It is evident from what has been said that an accurate prognosis in
+arteriosclerosis is no easy matter. Were arteriosclerosis a simple
+disease of an acute character there might be grounds for giving a more
+or less definite prognosis. The most that can be said is that
+arteriosclerosis is always a serious disease from the time that symptoms
+begin to make themselves known. The gravity depends altogether on the
+seat of the greatest arterial changes, and is necessarily greater when
+the seat is in the brain than when it is in the legs or arms.
+
+The attitude of the patient himself also determines to a great extent
+the prognosis. Some men, especially those who have always enjoyed good
+health, turn a deaf ear to warnings and instead of ordering their lives
+according to the advice of the physician, persist in going their own way
+in the hope that the luck that has always been with them will continue
+to stand at their elbows. Neither firmness nor pleadings avail with some
+men. The only salve for the conscience of the physician is that he has
+done his best to steer the patient away from the shoals and breakers. In
+others who realize their condition and take advantage of the advice
+given as to the regulation of their lives, the prognosis is generally
+favorable.
+
+To sum up the chapter in a few words, I should say: Always remember that
+the patient is a human being; study his habits and character and mode of
+life; look at him as a whole; take everything into consideration, and
+give always a guarded prognosis.
+
+
+
+
+CHAPTER XII
+
+PROPHYLAXIS
+
+
+Arteriosclerosis comes to almost every one who lives out his allotted
+time of life. As has been noted within, many diseases and many habits of
+life are conducive to the early appearance of arterial degeneration.
+Decay and degeneration of the tissues are necessary concomitants of
+advancing years and none of us can escape growing old. From the period
+of adolescence certain of the tissues are commencing a retrograde
+metamorphosis, and hand in hand with this goes the deposit of fibrous
+tissue which later may become calcified. The arterial tissue is no
+exception to this rule, and we have already shown that certain changes
+normally take place as the individual grows older, changes which are
+arteriosclerotic in type and are quite like those caused in younger
+people by many of the etiologic factors of the disease.
+
+We are absolutely dependent upon the integrity of our hearts and blood
+vessels for the maintenance of activity and span of life. Respiration
+may cease and be carried on artificially for many hours while the heart
+continues to beat. Even the heart has been massaged and the individual
+has been brought back to life after its pulsations have ceased, but such
+cases are few in number. We can not live without the heart beat and the
+prophylaxis of arteriosclerosis consists in the adjustment of our lives
+to our environment, so that we may get the maximum amount of work
+accomplished with the minimum amount of wear and tear on the blood
+vessels.
+
+The struggle for existence is keen. Competition in every profession or
+trade is exceedingly acute, so much so that to rise to the head in any
+branch of human activity requires exceptional powers of mind. Among
+those who are entered in this keen competition, the fittest only can
+survive for any period of time. The weaklings are bound to succumb. A
+scion of healthy stock will stand the wear and tear far better than will
+the progeny of diseased parentage.
+
+It is only necessary to call attention to the part that alcohol,
+syphilis and insanity play in heredity. These have been discussed fully
+in the earlier part of this book.
+
+We live rapidly, burning the candle at both ends. It is not strange that
+so many comparatively young men and women grow old prematurely. While
+heredity is a factor as far as the prophylaxis of arteriosclerosis is
+concerned, of far more importance is the mode of life of the individual.
+Scarcely any of us lead strictly temperate lives. If we do not abuse our
+bodies by excessive eating and drinking and so wear out our splanchnic
+vessels and cause general sclerosis by the high tension thereby induced,
+we abuse our bodies by excessive brain work and worry with all their
+multitudinous evils. The prophylaxis of arteriosclerosis might well be
+labeled, "The plea for a more rational mode of life." Moderation in all
+things is the keynote to health, and to grow old gracefully is an art
+that admits of cultivation. Excesses of any kind, be they mental, moral,
+or physical, tend to wear out the organism.
+
+People habitually eat too much; many drink too much. They throw into the
+vascular system excessive fluid combined frequently with toxic products
+that cause eventually a condition of high arterial tension. It has been
+shown how poisonous substances absorbed from the intestines have some
+influence on the blood pressure. Anything that causes constant increase
+of pressure should be studiously avoided.
+
+Mild exercise is an essential feature of prophylaxis. One may, by
+judicious exercise and diet, make of himself a powerful muscular man
+without, at the same time, raising his average blood pressure. The man
+who goes to excess and continually overburdens his heart, will suffer
+the consequences, for the bill with compound interest will be charged
+against him. It is a great mistake for any one to work incessantly with
+no physical relaxation of any kind, and yet, after all, it is not so
+much physical relaxation that is necessary, as the pursuit of something
+entirely different, so that the mind may be carried into channels other
+than the accustomed routes. Diversification of interests is as a rule
+restful. That is what every man who reaches adult life should aim at.
+Hobbies are sometimes the salvation of men. They may be ridden hard, but
+even then they are helpful in bearing one completely away from daily
+cares and worries. The man who can keep the balance between his mental
+and physical work is the man who will, other things being equal, live
+the longest and enjoy the best health.
+
+Nowadays the trend of medicine is toward prophylaxis. We give the state
+authority to control epidemics so far as it is possible by modern
+measures to control them.
+
+We urge over and over again the value of early diagnosis in all chronic
+diseases, for we know that many of them, and this applies particularly
+to arteriosclerosis, could be prevented from advancing by the
+recognition of the condition and the institution of proper hygienic and
+medicinal treatment.
+
+_It is the patent duty of every physician to instruct the members of his
+clientele in the fundamental rules of health._ Recently the President of
+the American Medical Association, in his address before the 1908
+meeting, urged the dissemination of accurate knowledge concerning
+diseases among the laity. While this may be done by city and state
+boards of health, it seems far better for the modern trained physician
+to work among his own people. With concise information concerning the
+modes of infection and the dangers of waiting until a disease has a firm
+hold before consulting the health mender, people should be able to
+protect themselves from infections and be able to nip chronic processes
+in the bud. But it is difficult to turn the average individual away from
+the habit of having a drug-clerk prescribe a dose of medicine for the
+ailment that troubles him. It is really unfortunate that most of the
+pains and aches and morbid sensations that one has speedily pass away
+with little or no treatment. Herein lies the strength of charlatanism
+and quackery. Unfortunate, yes, for a man can not tell whether the
+trivial complaint from which he suffers is any different from the one
+that was so easily conquered six months ago. But instead of recovering,
+he grows worse. Hope that springs eternal in the human breast, leads him
+to dilly-dally until he at last seeks medical advice, only to find that
+the disease has made such progress that little can be done.
+
+_Instruct the public to consult the doctors twice a year._ The dentists
+have their patients return to them at stated intervals only to see if
+all is well. _How much more rational it would be if men and women past
+the age of forty had a physical examination made twice a year to find
+out if all is well._
+
+The prophylaxis of arteriosclerosis is moderation in all the duties and
+pleasures of life. This in no sense means that a man has to nurse
+himself into neurasthenia for fear that something will happen to him. As
+one grows in years exercise should not be as violent as it was when
+younger, and food should be taken in smaller quantities. Many forms of
+exercise suggest themselves, particularly walking and golf. Walking is a
+much neglected form of exercise which, in these modern days with our
+thousand and one means of locomotion, is becoming almost extinct. There
+is no better form of exercise than graded walking. To strengthen the
+heart selected hill climbing is one of the best therapeutic methods that
+we have. The patient is made to exercise his heart just as he is made to
+exercise his legs, and as with exercise of voluntary muscles comes
+increase in strength, so by fitting exercise may the heart muscle be
+increased in power. A warning should be sounded, however, against over
+exercise. This leads naturally to hypertrophy with all its disastrous
+possibilities. Men who have been athletes when young should guard
+against overeating and lack of exercise as they grow older. Many of the
+factors which favor the development of arteriosclerosis are already
+there, and a sedentary, ordinary life, such as office all day, club in
+afternoon, a few drinks and much rich food, will inevitably lead to
+well-advanced arterial disease.
+
+Karl Marx in his famous Socialistic platform said: "No rights without
+duties; no duties without rights." So we may paraphrase this and say:
+"No brain work without moderate physical exercise in the open air; no
+physical exercise without moderate brain work."
+
+There is yet one other point that is important, the combination of
+concentrated brain work and constant whiskey drinking. This is most
+often seen in men of forty-five to fifty-five, heads of large business
+concerns who habitually take from six to twelve drinks of whiskey daily,
+and with possibly a bottle of wine for dinner. Such men appear ruddy and
+in prime health but, almost invariably, careful examination will reveal
+unmistakable signs of arterial disease. There is usually the enlarged
+heart and pulse of high tension with or without the trace of albumin in
+the urine. The lurking danger of this group of manifestations has so
+impressed the medical directors of several of the large insurance
+companies that a blood pressure reading must be made on all applicants
+over forty years of age. Should high blood pressure be found, the
+premium is increased, as the expectation of life is proportionately
+shorter in such men than in normal persons.
+
+Therefore, let every physician act his part as guardian of health. Only
+in this way is the prophylaxis of arteriosclerosis possible.
+
+
+
+
+CHAPTER XIII
+
+TREATMENT
+
+
+Although it has been rather dogmatically stated (vide supra) that every
+one who reaches old age has arteriosclerosis, it must not be inferred
+that absolutely no exceptions to this rule are found. Cases are known
+where persons of ninety years even had soft arteries, and we have seen
+persons of eighty whose arteries could not be palpated. When infants and
+children are seen with considerable sclerosis, it proves that, after
+all, it is the quality of the tissue even more than the wear and tear,
+that is the determining factor in the production of arteriosclerosis. It
+would be well if those who can not bring healthy progeny into the world
+were to leave this duty to those who can.
+
+In general the treatment of arteriosclerosis is prophylactic and
+symptomatic. In the preceding chapter I had something to say about
+prophylaxis in general; I must again refer to it in detail.
+
+Arteriosclerosis is essentially a chronic progressive disease, and the
+secret of success in the management of it is not to treat the disease or
+the stage of the disease, but to treat the patient who has the disease.
+To infer the stage of the disease from the feeling of the sclerosed
+artery, may lead to serious mistakes. Persons with calcified arteries
+may be perfectly comfortable, while those with only moderate thickening
+may have many severe symptoms. The keynote is individualization. It is
+manifestly absurd to treat the laboring man with his arteriosclerosis as
+one would treat the successful financier. The habits, mode of life,
+every detail, should be studied in every patient if we expect to gain
+the greatest measure of success in the treatment. One may treat fifty
+patients who have typhoid fever by a routine method and all may
+recover. Individualizing, while of great value in the treatment of acute
+diseases, yet is not absolutely essential in order that good results may
+be obtained. Far different is it when treating a disease like
+arteriosclerosis. One who relies on textbook knowledge will find himself
+at a loss to know what to do. Textbooks can only outline, in the
+briefest manner, the average case, and no one ever sees the average book
+case. At the bedside with the patients is the place to learn
+therapeutics as well as diagnosis. All that can be hoped for in
+outlining the treatment of arteriosclerosis is to lay down a few
+principles. The tact, the intuition, the subtle something that makes the
+successful therapeutist, can not be learned from books. So the man who
+treats cases by rule of thumb is a failure from the beginning. There are
+certain general principles that will be our sheet anchors at all times
+and for all cases. The art of varying the application of these
+fundamentals to suit the individual case, is not to be culled from
+printed words.
+
+
+=Hygienic Treatment=
+
+Every man is more or less the arbiter of his own fate. Granted that he
+has good tissue to begin life, his own habits and actions determine his
+span of comfortable existence. No one cares to live after his brain
+begins to fail, and the failing brain is often due to disease of the
+cranial arteries. The hygienic treatment resolves itself into advice in
+regard to prophylaxis.
+
+First and foremost is exercise. It has seemed to us that the revival of
+out-of-door sports is one of the best signs of promise of the
+preservation of a virile, hardy race. That women, as well as men,
+indulge in the lighter forms of out-of-door exercise should bring it
+about that the coming generation will start in life under the most
+advantageous conditions of bodily resistance.
+
+Among all the forms of exercise, golf probably is the best. It is not
+too violent for the middle-aged man, yet it gives the young athlete
+quite enough exercise to tire him. It is played in the open. One is
+compelled to walk up and down in pleasant company, for golf is
+essentially a companionable game, while he reaps the full benefit of the
+invigorating exercise. The blood courses through the muscles and lungs
+more rapidly; the contraction of the skeletal muscles serves to compress
+the veins and so to aid the return of blood to the heart: the lungs are
+rendered hyperemic, deeper and fuller breaths must be taken; oxidation
+is necessarily more rapid, and effete products, which if not completely
+oxidized would possibly act as vasoconstrictors, are oxidized to
+harmless products and eliminated without irritating the excretory
+organs.
+
+Other forms of out-door exercise that can be recommended are tennis,
+canoeing, rowing, fishing, horseback riding, swimming, etc. Tennis is
+the most violent of all the sports mentioned and might readily be
+overdone. Rowing as practiced by the eights at college is undoubtedly
+too violent a form of exercise, and may be productive in later life of
+very grave results. Canoeing is a delightful and invigorating exercise.
+The muscles of the arms, shoulders, and trunk are especially used, the
+leg muscles scarcely at all. Nevertheless, the deep breathing that
+necessarily comes with all chest exercises aerates every portion of the
+lungs, and is of great benefit to the whole body.
+
+Swimming as an exercise has much to recommend it. In this sport all the
+muscles take part and at the same time the chest is broadened and
+deepened.
+
+All these methods of using the muscles to keep oneself in trim, so to
+speak, are part and parcel of the general hygienic mode of life that is
+conducive to a healthy old age. Exercise can be overdone, as eating can
+be overdone. Both are essential and yet both can be the means of
+hastening an individual to a premature grave.
+
+When the arteriosclerosis has advanced so far that it is easily
+recognizable, certain forms of exercise should be absolutely prohibited.
+Such are tennis, rowing and swimming. Horseback riding to be allowed
+must be strictly supervised. At times this may be an exceedingly violent
+exercise. As an out-of-door sport, there is nothing that equals golf.
+The physician, knowing the character of the course, and the length of
+it, can say to his patient that he may play six, nine, twelve, or
+eighteen holes, depending on the patient's condition.
+
+For those who are not able to get out, exercise in the room with the
+windows open must take the place of out-of-door sports. Here the use of
+chest weights is a most excellent means of keeping up the tone of the
+muscles. By adjusting the weights, the exercise may be made light,
+medium, or heavy. Every physician should be familiar with the chest
+weight exercises. They are not as good as open air exercise but they
+undoubtedly have been the means of saving years of life to many patients
+with arterial disease.
+
+There comes a time when all forms of exercise must be prohibited on
+account of the dyspnea, edema, dizziness, etc. It seems unwise to keep
+such a patient in bed, even though the edema be considerable. Once on
+his back in bed he becomes weak, and the danger of edema of the lungs or
+hypostatic congestion of the bases, with subsequent bronchopneumonia, is
+very great.
+
+Such patients may be allowed to sit up in a comfortable chair with the
+legs supported straight out on a stool or other chair. The half
+reclining position is not easy to assume in bed. Considerable ingenuity
+must often be exercised by the physician in making the patient
+comfortable without increasing the symptoms from which the patient
+suffers following the least amount of exercise. Although such persons
+can not exercise actively, they should have passive exercise in the form
+of massage, carefully given, so that no injury is done to the rigid
+vessels. It is possible to rupture a vessel, the walls of which are
+encrusted with lime salts, and full of small aneurysmal dilatations.
+Every patient must be watched carefully and measures instituted for the
+individual.
+
+
+=Balneotherapy=
+
+As a tonic and invigorator, the cold or cool bath (shower or tub), in
+the morning on arising can be highly recommended. It promotes skin
+activity, is a stimulant to the bowels and kidneys and to the general
+circulation, besides being cleansing. We find today that the morning
+bath has become such a necessity to the average American that all new
+hotels are fitted with private baths, and old hotels, in order to get
+patronage, are arranging as many baths connected with sleeping rooms as
+is possible. Our generation assuredly is a ruddy, clean-bodied one. What
+the actual results of this out-door life and frequent bathing will be
+for the race remains to be seen, but one can not but feel that it must
+build up a stronger, more resistant race of people, who not only enjoy
+better health than did their forefathers, but enjoy it longer.
+
+Not every one can stand a cold bath. It is folly to urge it on one to
+whom it is distasteful, or on one who does not feel the comfortable glow
+that should naturally result. For the well, or those with a tendency to
+arteriosclerosis, or those in whose families there have been several
+members who had early arteriosclerosis, such proceedings as recommended
+could not be improved upon. However, for the person who has well
+recognized sclerosis, only warm baths should be advised, and these not
+daily. The water should be at a temperature of 90-95° F. Care should be
+taken that persons sent to spas be cautioned against hot baths. It is
+not inconceivable that the increased force of the heart beat that
+accompanies a hot bath might be sufficient to rupture a small cranial
+vessel. Hence, Turkish and Russian baths should be most unqualifiedly
+condemned. As a matter of fact, persons vary so in their habits with
+regard to bathing that what might suit one person would do another much
+harm.
+
+
+=Personal Habits=
+
+The personal habits of the individual, more than any other factor,
+determine whether or not arteriosclerosis sets in early in his life. The
+man or woman who is moderate in eating and drinking, sees that the
+kidneys are kept in good condition, and attends strictly to regularity
+of the bowels, lays a good basis for the measure of health which is so
+essential for happiness. It has been shown that sclerosis of the
+splanchnic vessels may be due to constant irritation of toxic products
+elaborated in digesting constantly enormous meals. In obstinate
+constipation, many poisons, the nature of which we do not know, are
+absorbed and circulate in the blood. We have not sufficient data to
+prove that constipation favors the production of arteriosclerosis, but
+our impression has been that it does favor it. Constipation can often be
+relieved by a glass of water before breakfast, a regular time to go to
+stool, and abdominal massage or exercises. Some maintain that it is a
+bad habit only, and can be readily overcome. Whatever is done, avoid
+leading the patient into the drug habit, for the last state of the
+patient will be worse than the first. Habits of sleep are not of such
+great importance. Most persons get enough sleep except when under severe
+mental strain. Most adults need from seven to eight hours' sleep,
+although some can do all their work and keep in prime health on five or
+six hours' sleep.
+
+Tobacco has been accused of causing many ills and has been thereby much
+maligned. We can not see that the use of tobacco in any form in
+moderation is harmful to most men. Undoubtedly the blood pressure is
+raised when mild tobacco poisoning occurs, and individual peculiarities
+of reaction to the weed are multitudinous. But to condemn offhand its
+use is the height of folly. There is no reason why the arteriosclerotic
+who has always used tobacco in moderation, should not continue to use
+it, whether he smoke cigarettes, cigars, or pipe. His supply should be
+decreased, but there is no sense in depriving a man of one of the
+solaces of life, unless, as is sometimes the case, abstinence is easier
+for the patient than moderation.
+
+As for alcohol, opinions differ widely.[19] Some see in alcohol one of
+the most frequent causes of arteriosclerosis; others do not believe that
+the part played by alcohol is a serious one, only in conjunction with
+other poisonous substances is it dangerous. Probably unreasoning
+fanaticism has had much to do with the wholesale condemnation of
+alcoholic beverages. The general effect of alcohol is to lower the blood
+pressure by causing marked dilatation of all the vessels of the skin.
+True, the alcohol circulates in the blood, and is broken up in the
+liver, and this organ would seem to bear the brunt of the harm done.
+Alcoholic drinks in moderation, I do not believe have any deleterious
+effect on health. On the contrary, I believe that they may in some cases
+assist digestion and assimilation. Indiscriminate indulgence is to be
+condemned, as is overindulgence in exercise or eating. What may be
+moderate for A, might be excessive for B. Every man is then the arbiter
+of his own fortune and within his own limits can indulge moderately (a
+relative term after all) without fear of doing himself harm. In advanced
+arteriosclerosis it is necessary to decrease the supply of alcohol just
+as it is necessary to cut down the food supply. This must rest entirely
+on the judgment of the physician, who must not act arbitrarily, but must
+have his reasons for every one of his orders.
+
+ [19] Discussion of alcohol at present has value only as it relates
+ to the past. The present is dry. The future is in the lap of the gods.
+
+
+=Dietetic Treatment=
+
+Most persons eat too much. We not only satisfy our hunger, but we
+satisfy our palates, and, instead of putting substantial foodstuffs
+into our stomachs, we frequently take unto ourselves concoctions that
+defy description.
+
+Foodstuffs are composed of one or all of three classes: (1) proteins,
+(2) fats, (3) carbohydrates. As examples of the first are beef and white
+of egg; of the second, the oils, butter, lard; of the third, sugar,
+potato, beet, corn, etc.
+
+The physiologists and chemists have shown us that both endogenous and
+exogenous uric acid in excess will cause a rise of blood pressure, but
+the bodies most concerned in the production of elevated blood pressure
+are the purin bodies, those organic compounds which are formed from
+proteins and represent chemically a step in the oxidation of part of the
+protein molecule to uric acid. Red meat contains more of the substances
+producing purin bodies than any other one common foodstuff, and for this
+reason the excessive meat eater is, _ceteris paribus_, more apt to
+develop arteriosclerosis comparatively early in life.
+
+The fats and carbohydrates contain practically no substances that react
+on the body of the ordinary individual in a deleterious manner during
+their digestion. The extra work that is put on the heart by the
+formation of many new blood vessels in adipose tissue is the only
+harmful effect of overindulgence in these foodstuffs.
+
+It has been found that nitrogen equilibrium can be maintained at a wide
+range of levels. Formerly 135-150 gms. of protein daily were considered
+necessary for a man doing light work. Now it is known that half that
+amount is sufficient to keep one in nitrogenous equilibrium, and to
+enable one to keep his weight. A person at rest requires even less than
+that. One who is engaged in hard physical labor burns up more fuel in
+the muscles, and so must have a larger fuel supply.
+
+Although we habitually eat too much we drink too little water. For those
+who have any form of arterial disease an excess of fluid is harmful, as
+the vessels become filled up and a condition of plethora results, which
+necessarily reacts injuriously on the heart and circulation. The
+drinking of a glass of water during meals is, in the author's opinion,
+good practice. The water must be taken mouthful at a time, and not
+gulped down. If this is done, there results sufficient dilution of the
+solid food to enable the gastric juices successfully and rapidly to
+reach all parts of the meal.
+
+Some are in favor of a rigid milk diet for those who have
+arteriosclerosis. Some men have lived on nothing but milk for several
+years and have not only kept in good health, but have actually gained
+weight and led at the same time active lives. It has been held by others
+that rigid milk diet is positively harmful on account of the relatively
+large quantity of calcium salts that are ingested. This was thought to
+favor the deposition of calcareous material in the walls of the already
+diseased arteries. While possibly there may be some danger of increased
+calcification, the majority of clinicians are in favor of a milk cure
+given at intervals. Thus the patient is made to take three to four
+quarts daily for a period of a month. There is then a gradual return to
+a general diet, exclusive of meat, for several weeks, then another rigid
+milk diet period.
+
+If we are bold enough to follow Metschnikoff in his theories of
+longevity, we might advise resection of the large intestine, on the
+ground that it is an enormous culture tube that produces prodigious
+amounts of poisonous substances which are thrown into the general
+circulation. To combat such a grave (?) condition as the carrying of
+several feet of large intestine, we are recommended to take buttermilk
+or milk soured by means of the _b. acidus lacticus_. Clinical experience
+has taught that in arteriosclerosis buttermilk is of great value,
+whether it be the natural product, or made directly from sweet milk by
+the addition of the bacilli. The latter is a smoother product and has,
+to my mind, a delightful flavor. It may be diluted with Vichy or plain
+soda water. Cases that can not take milk or any other food will often
+take buttermilk, and do well on this restricted diet. From two to four
+quarts daily should be taken. It should be drunk slowly as should milk.
+
+
+=Medicinal=
+
+It has long been thought that the iodides have some specific effect on
+the advancing arteriosclerosis, checking its spread, if not really
+aiding nature to a limited restoration of the diseased arteries. It is
+possible that the eulogies upon the iodides owe their origin to the
+successful treatment of syphilitic arteriosclerosis, in which condition
+these drugs have a specific action. However that may be, there is no
+doubt that the administration of sodium or potassium iodide is good
+therapeutics in cases of arteriosclerosis.
+
+Unfortunately many persons have such irritable stomachs that they can
+not take the iodides, even though they be diluted many times. They may
+be made less irritating by giving them with essence of pepsin. Unless
+the case is syphilitic, it is doubtful whether it is of value to
+increase the dose gradually until a dram or even more is taken three
+times daily after meals. Usually a maximum dose of ten grains seems to
+be quite sufficient. This may be taken three times a day, well diluted,
+for three months. There follows a month's rest, then the treatment is
+resumed for another period of three months, and so on. Either sodium or
+potassium iodide in saturated solution may be given. The sodium salt is
+possibly less irritating, and contains more free iodine than the
+potassium salt, although the latter is more generally used. The
+strontium iodide may also be used.
+
+One sees a patient now and then who can not take the iodides, however
+they may be combined. For such patients one may obtain good results with
+iodopin, sajodin, or other of the preparations put up by reputable
+firms. Personally I have never yet seen a patient who could not take the
+ordinary iodides in some form or other, and I am opposed to ready made
+drugging.
+
+The action of the iodides is to lower the blood pressure, and they are
+of greatest value when the blood pressure is high, and when headache and
+precordial pain are present.
+
+When the case is moderately advanced, very mild doses, gr. 1/2, morning
+and evening, of the thyroid extract may be given. It is generally
+believed that the internal secretion of the thyroid and the adrenal are
+antagonistic. That the thyroid secretion lowers blood pressure in
+certain forms of hypertension is certain, possibly on account of its
+iodine content. Some combinations of iodine and thyroid such as the
+iodothyroidin have been used and have had some measure of success
+attributed to them.
+
+Hypertension does not always demand active measures for its reduction.
+Viewed from the physiologic standpoint, hypertension is but the
+expression of a compensating mechanism which is designed to keep the
+blood moving through narrowed channels. Heart hypertrophy then is
+absolutely essential to the maintenance of life. It has been said that
+the highest blood pressures occur in chronic disease of the kidneys. The
+poisonous substances produced in the kidneys must exert their action
+through absorption into the general blood stream. This toxin may be
+completely eliminated, if we accept as our criterion the reduction of
+tension to normal together with the complete return of the affected
+individual to health. A concrete example is as follows: A man aged 44
+years was brought to the Milwaukee County Hospital in coma. His systolic
+blood pressure was over 280 mm. Hg, diastolic 170 mm., his urine
+contained considerable albumin and many casts. He had general anasarca.
+Venesection was done at once and 300 c.c. blood obtained. Immediately
+following this operation the pressure was 210-150, but within twelve
+hours it was again above 280-170. He was given no medication to reduce
+pressure except that he was freely purged. He was given a steam sweat
+bath daily. Frequent blood pressure readings were taken. Within seven
+days the pressure was 130-86. He had, in the meantime, completely
+recovered from his symptoms. He was kept in the hospital for two weeks
+longer assisting in the work on the ward, and he was discharged with a
+pressure (systolic) between 130 and 136 diastolic 80-84. The treatment
+was rest in bed, free purging, venesection, and sweat baths, simple but
+exceedingly effective.
+
+Should there be actual indications for reducing the blood pressure, I
+must admit that it can not always be done. The majority of cases will do
+well on the sodium nitrite or erythrol tetranitrate. However, these do
+not always lower blood pressure and keep it within normal limits. When a
+man has very high tension we do not wish to reduce it to what it should
+normally be for the age of the patient, as symptoms of collapse might
+set in at any time under such conditions.
+
+Observations made with the sphygmomanometer[20] show that the effect of
+nitroglycerin is transient or of no effect except in doses which are
+relatively enormous (one drop of the one per cent solution given every
+hour). Sodium nitrite may lower the blood pressure but the effects will
+have worn off in two hours. It is the same with erythrol tetranitrate.
+Sodium sulphocyanate in doses of from one to three grains three times a
+day is highly recommended by some. My own experience with it does not
+lead me to believe that it is of any great value in hypertension. It,
+however, may be tried. Benzyl benzoate has been used recently to reduce
+the high blood pressure of hypertension. Macht has reported some
+success. In the author's hands it has been efficacious in a few cases.
+As long as the patient takes the drug the pressure may be slightly
+reduced, but upon the withdrawal of the drug the pressure returns to its
+former level. It is well worth a trial and further experimentation may
+reveal better methods of administration. The dose is from 2 to 6 c.c.
+mixed with water at intervals.
+
+ [20] Miller, Jos. L.: Hypertension and the Value of the Various
+ Methods for Its Reduction. Jour. Am. Med. Assn., 1910, liv, p. 1666.
+
+In the hypertension of the menopause some have had success with large
+doses of corpus luteum extract. As a matter of fact the drug treatment
+of hypertension, when it becomes necessary to treat this condition with
+drugs, has suffered a notable set-back since more careful control has
+been made with the blood pressure instruments. In giving any of the
+depressor drugs their action should be controlled by blood pressure
+measurements, for only in this way can we be sure that the drug is
+exerting its physiological effect and we may expect results. The
+individual reaction to these drugs varies greatly and no rule for dosage
+can be dogmatically laid down. The only successful therapy is rigid
+individualization. This is the keystone to treatment in cases of
+arteriosclerosis and high tension.
+
+It must not be inferred from what has been said that the nitrites are of
+no value. They are of decided value but they have their limitations. The
+most evanescent of these drugs is amyl nitrite. This is put up in the
+form of capsules, or pearls, containing from one to three minims. When
+it is desired to dilate the peripheral vessels suddenly, one or two of
+these capsules are broken in a cloth held to the nose. The effect is
+almost instantaneous. There is flushing of the face and other peripheral
+vessels, particularly near the head, denoting a relaxation and widening
+of the bed of the blood stream, and a consequent decrease in pressure in
+the arteries. These effects are over in a short while. It is only used
+in attacks of cardiac spasm, as in angina pectoris. Nitroglycerin, the
+Spiritus Glonoini of the U. S. P., acts in about the same manner as amyl
+nitrite but the effects last usually a trifle longer. One drop of the
+one per cent solution may be given every hour until physiologic effects
+are produced. It may be given hypodermically. This may be a means of
+reducing pronounced high tension. This drug has been found of benefit
+especially in cases where arteriosclerosis combined with chronic
+nephritis causes cardiac asthma. The other drug which may be of service
+in these conditions, one whose sphere of action is somewhat broader,
+because its effects are more lasting, is sodium nitrite. This is given
+in water in doses of one to three or five grains every four hours. Some
+have objected to the use of this drug, but my experience has made me
+place considerable confidence in its harmlessness, provided that the
+patient is carefully watched. This, however, applies to all of the
+nitrite compounds. My experience with erythrol tetranitrate is not
+large. It may be used in place of sodium nitrite.
+
+For a mild case, one often finds that sweet spirits of niter is
+sufficient to control the pressure and relieve the distressing symptoms,
+and it is undoubtedly the least harmful of all the nitrites. Drugs that
+are of great value, but of which little is noted in textbooks, are
+aconite and veratrum viride. Both of these drugs are well known to be
+marked circulatory depressors. Veratrum viride in my experience should
+be very cautiously used, and never used unless a trained attendant is
+constantly at hand. With regard to aconite I have no such feeling, and a
+mixture of tincture of aconite and spiritus etheris nitrosi may be given
+for several weeks with no fear of doing any harm. Personally, of all the
+drugs mentioned, I prefer the nitrite of sodium or the combination just
+given. They may be advantageously alternated.
+
+My own feeling is that the most successful means of treatment of acute
+high tension is without the use of drugs. The most important measure is
+absolute rest in bed. This often suffices to lower the blood pressure
+and to arrest the symptoms produced by high tension. Venesection I
+believe is also of value. True the arterioles appear to contract almost
+immediately upon the lessened quantity of blood, or there is immediate
+interchange of serum from the tissues which brings the blood volume
+back to the original amount. Whatever happens the pressure is not
+greatly reduced, at times not reduced at all, but often the symptoms are
+relieved. Hot packs or sweat baths assuredly do reduce the pressure in
+many cases. This seems to me to be an exceedingly valuable measure.
+Finally the diet should be nourishing, but very light, not too much
+fluid should be ingested, and the bowels should be freely opened.
+
+With the fibrolysin of Merck, I have had no experience. Some men assert
+that they have had good results from its use, but on the whole the
+evidence is not highly favorable.
+
+Morphine is invaluable. No drug is of such value in the nocturnal
+dyspneic attacks that occur in the late stages of arteriosclerosis when
+the heart or the kidneys are failing. Morphine not only relaxes spasm
+and quiets the cerebral centers, but is an actual heart stimulant under
+such conditions, and should never be withheld, as the danger of the
+patient's becoming addicted to its use is more fanciful than real.
+However, morphine, at times, suppresses the secretion of urine. So that
+if after trial the urine becomes scanty and the edema increases,
+recourse must be had to other drugs. The various hypnotics may be used
+with caution. One which seems to be very useful is adalin.
+
+As heart stimulants, one may use strychnine, spartein, caffein, or
+camphor. In desperate cases, where a rapidly diffusible stimulant is
+needed, a hypodermic syringeful of ether may be given, and repeated in a
+short while.
+
+Several years ago a so-called serum was brought out by Trunecek which
+was said to have a favorable effect on the metabolism of the vessel
+walls. It was given at first hypodermatically or intravenously but the
+former method was painful. It was later stated that given by mouth it
+acted just as well. The results with the Trunecek serum have not come up
+to the expectations that the early favorable reports promised. The
+original serum was composed as follows: NaCl, 4.92 gm.; Na_2SO_4, 0.44
+gm.; Na_2CO_3, 0.21 gm.; K_2SO_4, 0.40 gm.; aqua destil. q. s. ad. 100.0
+c.c. Later this was modified for internal use to the following
+prescription:
+
+ R_{x} Natrii chlor. 10. gm.
+ Natrii sulphat. 1. gm.
+ Natrii carbonat. 0.40 gm.
+ Natrii phosphat. 0.30 gm.
+ Calcii phosphat.
+ Magnesii phosphat. aa. 0.75 gm.
+ M. Ft. cachets No. XIII.
+
+The contents of every cachet corresponds to 15 c.c. of the fluid serum
+or to 150 c.c. of blood serum. The preparation called antisclerosin
+consists of the salts contained in the serum. As to its efficacy, I can
+not judge, as I have never felt that it was worth while to use it.
+Reports of cases in which it has been tried do not speak very highly of
+it.
+
+In the general treatment of arteriosclerosis, there is no one factor of
+more importance than the regular daily bowel movement. Attention to this
+may save the patient much discomfort and even acute attacks of cardiac
+embarrassment. The choice of the purgative is immaterial, with this
+reservation only, that the mild ones, such as cascara, rhubarb, licorice
+powder and the mineral waters, should be thoroughly tried before we
+resort to the more drastic purgatives. Plenolphthalein in 3 to 5 grain
+doses acts remarkably well in some people as a pleasant laxative.
+Agar-agar with or without cascara may be useful.
+
+Liquid paraffin under a variety of names is a most useful and
+efficacious laxative. As its action is purely mechanical it may be taken
+indefinitely without doing harm to the intestinal musculature.
+
+The old Lady Webster dinner pill is an excellent tonic aperient. When
+the heart is embarrassed and edema of the legs and effusion into the
+serous cavities have taken place, then it becomes necessary to use the
+drastic purgatives that cause a number of watery movements. Epsom salts
+given in concentrated form, elaterin gr. 1-12, the compound cathartic
+pill, blue mass and scammony, or even croton oil may be used. Since the
+observation of a greatly congested intestine from a patient who had been
+given croton oil, I have ceased to use this purgative, and I doubt much
+whether its use is ever justifiable in these cases.
+
+The management of the ordinary case of arteriosclerosis resolves itself
+into a careful hygienic and dietetic regime with the addition of the
+iodides, aconite, or the nitrites. A diet consisting of very little
+meat, alcohol in moderation or even absolutely prohibited, and not too
+much fluid should be prescribed. Condiments and spices should also be
+used sparingly. Cold baths, shower baths, cold and hot sheets
+alternating, are of great benefit in assisting the heart to do its best
+work by making the large capillary area of the skin more permeable. It
+is not true that such baths raise the blood pressure so markedly.
+Certain acts, as sneezing, violent coughing, etc., increase the blood
+pressure much more than judicious bathing.
+
+
+=Symptomatic Treatment=
+
+The fact that arteriosclerosis really loses much of its own identity
+and, in later stages, becomes merged with the symptomatology of the
+diseases of various organs, as the kidney, brain, heart, compels us, for
+completeness' sake, to say a few words about the treatment of these
+complications.
+
+One of the results of arteriosclerosis of the coronary arteries, angina
+pectoris, demands prompt treatment. In the acute attack, the chief
+object is to relieve the spasm and pain. Pearls of amyl nitrite should
+be inhaled, and morphine sulphate with atropine sulphate given
+hypodermatically at the very earliest moment. It is senseless to
+withhold morphine. The only possible reason for withholding it would be
+uncertainty as to the diagnosis. It is probably better to err on the
+safe side, and should the case prove to be one of pseudo angina, in the
+next attack sterile water can be given instead of the morphine and
+atropine.
+
+When a patient is seen in the condition of broken compensation with the
+much dilated heart, anasarca, dyspnea and suppression of urine, there is
+no better practice than venesection. Especially is this valuable when
+the tension is still fairly high and the individual is robust. Following
+the abstraction of six to eight ounces of blood (300-500 c.c.)[21] the
+whole picture changes, so that a man who a short while before was
+apparently at death's door, notices his surroundings and takes an
+interest again in life. This should be followed up with thorough
+purgation, and cardiac stimulants should be ordered. In such cases
+digitalis is useful, but its action is never so striking as in cases of
+this general character due to uncompensated valvular disease. It must be
+remembered that in arteriosclerosis the changes in the myocardium must
+be of a considerable grade for the heart to give away. Therefore,
+digitalis can not be expected to act on a diseased muscle as it acts on
+a comparatively healthy muscle. It is only in such cases of broken
+compensation that digitalis should ever be used.
+
+ [21] I have taken as much as 1700 c.c. from a large man. He
+ recovered and went back to work.
+
+Digitalis is not a general vasoconstrictor as used to be taught. Its
+action on the kidney is actually a vasodilator one. And in its action on
+the heart the digitonin dilates the coronary arteries, according to
+Macht, while the digitoxin acts on the heart muscle. Overdosing with
+digitalis has produced partial heart block in many cases. It is
+absolutely contraindicated in Stokes-Adams syndrome.
+
+There are, however, some cases, especially those with transudations,
+when digitalis may be carefully tried even though high tension be
+present. It is sometimes of advantage to combine digitalis with the
+nitrites although they are said to be physiologically incompatible.
+
+Still another drug, that is of great value in conditions such as have
+been described, is diuretin. This may be given in capsule or tablets,
+grs. x. three times daily. There is only one caution to express in the
+use of this drug. It should not be given when the kidneys are the seat
+of chronic inflammatory changes; in fact, actual harm may be done by
+administering the drug under such conditions.
+
+The same is true even to a greater extent with theocin. This is a
+powerful diuretic. If given by mouth it should be well diluted as it is
+most irritating to the stomach. It is best given intravenously in doses
+of two and a half to three grains dissolved in five to six cubic
+centimeters of distilled water. One must be reasonably sure that the
+kidneys are not the subject of chronic disease and are functionally,
+therefore, below par. The intravenous dose should not be given oftener
+than once in four days.
+
+For the pain in aneurysm, nothing (except, of course, morphine) is so
+valuable as iodide of potassium. Patients who are suffering agony, when
+put to bed and given KI grs. x. three times a day, soon lose all the
+distressing symptoms. This applies particularly to aneurysms of the arch
+of the aorta.
+
+When the sclerosis has affected the cerebral arteries to such an extent
+that symptoms result, the case is, as a rule, exceedingly grave. Not
+much can be done except to relieve the headaches and keep down the blood
+pressure, if this is high, by means of rest in bed, the iodides,
+aconite, or the nitrites. The cases of transient monoplegias or
+hemiplegias can be much relieved by careful hygienic measures and
+judicious administration of drugs. Much ingenuity is sometimes required
+to overcome the idiosyncrasies of patients, but care and patience will
+succeed in surmounting all such difficulties.
+
+The treatment of intermittent claudication is the treatment of
+arteriosclerosis in general. Sometimes the circulation in the affected
+leg or legs is much helped by daily warm foot baths. Light massage might
+be tried and the galvanic current may be used once or twice daily.
+
+There are a few distressing symptoms that occur usually late in the
+disease, when complications have already occurred, which frequently
+baffle the therapeutic skill of the physician. The chief of
+these--insomnia, dyspnea, and headache--may not be late manifestations,
+but insomnia and headache are frequently associated with the moderately
+advanced stages of arteriosclerosis. At times all the symptoms seem to
+be due to the high tension, the relief of which causes them to
+disappear. There are, unfortunately, times when high tension is not
+responsible for the headache and insomnia. Under these circumstances
+such drugs as trional, veronal, amylene hydrate, ammonol, etc., may be
+tried until one is found which produces sleep. For the headaches,
+phenacetin, alone or in combination with caffein and bromide of sodium,
+may be tried. Acetanilid, cautiously used, is at times of value. There
+have been cases of arteriosclerosis with low blood pressure, accompanied
+by severe headaches, that have been relieved by ergot. Codeine should be
+used with care, and morphine only as a very last resource.
+
+Great care must always be exercised in giving drugs that depress the
+circulation, for it is easily conceivable that more harm than good can
+come from injudicious drugging.
+
+
+
+
+CHAPTER XIV
+
+ARTERIOSCLEROSIS IN ITS RELATION TO LIFE INSURANCE
+
+
+The value of the early recognition of cases of arteriosclerosis and
+hypertension has been spoken of within, but it needs to be further
+emphasized. There is perhaps no class among physicians to whom is
+afforded a better opportunity of seeing early cases than the medical
+examiners of life insurance companies.
+
+The relationship between a patient and the physician whom he consults,
+and the applicant for life insurance and the examiner are diametrically
+opposite. In the former the patient desires to conceal nothing and the
+physician is called upon to diagnose and treat disease. In the latter
+the applicant, a presumably healthy person, may have much to conceal and
+the examiner is there to pass upon the state of health. The question is
+this--"Is the applicant now in good health?" It becomes then of vital
+importance for the examiner to be able to detect among other abnormal
+conditions the incipient signs of arteriosclerosis and of hypertension.
+Parenthetically it may be stated that arteriosclerosis and hypertension
+are not one and the same disease as has been so frequently insisted upon
+within; the former may occur without the latter but the latter can not
+from its very nature be present for long without arterial thickening
+supervening. It is necessary in discussing the question here to group
+the two conditions together in order to prevent needless repetition.
+
+Such a case as the following is common. A successful business man of
+forty-four years was brought to me by an agent in 1905 for examination.
+The man was six feet tall, weighed 218 pounds, had a ruddy color and
+looked to be the picture of health. He was not strictly intemperate, he
+never became intoxicated, but every day he drank three or four whiskies
+and often he had a bottle of wine for dinner in the evening. When he was
+examined his pulse was of good quality and owing to the fleshiness of
+the wrist it was difficult to say positively whether the radial artery
+was sclerosed or not. In the heart no murmurs were heard, and it was
+difficult to be sure that the left ventricle was enlarged. There was,
+however, a slight but definite accentuation of the second sound at the
+aortic cartilage which might readily have been overlooked had the
+patient not been stripped and a careful examination made with the
+stethoscope. Upon taking the blood pressure it was found to be from
+170-175 mm. of Hg. The urine specimen examined at the visit was normal,
+no casts were found. The applicant was seen at his home and the blood
+pressure measured. It was again the same. He was seen a third time and
+practically the same systolic blood pressure was found. Under protests
+from all the agency staff the man was declined. Two years later he died
+of apoplexy. The man was angry at being refused. Instead of looking the
+matter squarely in the face he thrust aside the idea that there was
+anything the matter with him. He had never had one ill day in his life,
+his forebears had lived to ripe old age, and he was sure that he knew
+more about himself than the examiner.
+
+Had this applicant showed a sense of reasonableness he should have been
+grateful to the doctor for calling his attention to a condition which
+surely would sooner or later prove either fatal itself or lead to some
+fatal lesion. It was learned that this man had gone directly to his
+family physician who laughed at such nonsense as had been told the (now)
+patient by the examiner.
+
+Another illustration of a slightly different type of case is afforded in
+the following history.
+
+A man of fifty years of age, five feet ten in height and 164 lbs. in
+weight, was brought for examination. In his youth there was a history
+of a mild attack of scarlet fever. He was almost a total abstainer,
+rarely taking liquor in any form. Physically he appeared to be an
+excellent risk. However, on examining the heart it was found that there
+was slight hypertrophy with an accentuated second aortic sound at the
+base, and the blood pressure was 180 mm. of Hg. Some sclerosis of the
+radial arteries was found. One company had refused him on account of
+albumin in the urine. There was none in the first specimen which was
+passed while in the office. The specific gravity was 1014. A morning
+specimen was obtained and contained a trace of albumin. Several
+specimens were then examined. Some contained albumin, some had no
+albumin content. The man was declined; no protests from the agent as
+albumin had been found. There was something tangible in that. Had the
+applicant been refused on account of his high tension, sclerosis of the
+radials, and slightly enlarged heart there would undoubtedly have been
+protests. And yet an applicant revealing such a state of the
+cardiovascular system without albumin in the urine should unhesitatingly
+be declined. Attention has been called to hypertension as an early, and
+some think an invariable, sign of chronic nephritis. My own experience
+has confirmed me in the belief that in hypertension the kidneys are
+often the seat of chronic interstitial changes. Careful palpation of the
+radial and brachial arteries will in every case reveal more or less
+thickening.
+
+There is yet another group of cases which the examiner sees as healthy
+subjects, namely those cases of sclerosis of the peripheral arteries
+without sclerosis of the aorta and without high tension. In such cases
+the radials, brachials, temporals and other superficial arteries are
+readily palpable, sometimes even revealing irregularities along the
+course of a vessel. Such cases are not subjects for insurance. The
+recognition of such a condition is of great importance to the one who
+has it and he should be urged to go to his regular physician for
+thorough examination. Should the physician ridicule the idea, as has
+happened to me more than once when I was actively engaged in insurance
+work, the examiner has done his full duty to the company, the applicant,
+and himself.
+
+A life insurance examiner has a difficult position to fill. He has four
+people to satisfy; the applicant, the agent, the medical director and
+himself. The straight and narrow path of strict honesty is his only
+salvation. By being honest with himself he necessarily gives a square
+deal to the other three parties.
+
+No applicant who has palpable arteries or hypertension can be considered
+a first class risk. It can not be denied that men with arteriosclerosis
+live to an advanced age and may even outlive those who have apparently
+normal arteries, but the average life expectancy at any age for an
+arteriosclerotic is less than that for a normal person. The apparently
+healthy applicant who learns for the first time when examined for life
+insurance that he has the early or moderately advanced signs of arterial
+disease, should thank the agent and examiner for showing him the danger
+signals ahead. The sensible man then orders his life so that he puts as
+little strain on his heart, arteries, and kidneys as possible and may
+add many years to his life.
+
+It is on account of this very insidiousness of onset that I have
+elsewhere urged as a prophylactic measure the examination every six
+months of all persons over forty years of age. I am more and more
+convinced that it is of vital importance to the health of the public.
+
+As I have remarked, the average man consults his dentist at least once a
+year so that no tooth may be so far diseased that it can not be saved.
+It is purely a means of preserving the teeth. Why not do the same with
+the whole body? Of what use is it to save the teeth and lose the body?
+It seems to me that the great army of life insurance examiners are in an
+enviable position in their ability to add years of life to many men and
+women. I doubt whether they realize their importance in the campaign for
+health. I should urge life insurance companies not to employ recent
+graduates unless they have had at least a year's hospital experience.
+For the company as well as for the individuals I believe that there is a
+prognostic sense which the examiner should have and this can only be
+acquired by experience.
+
+I believe that arteriosclerosis and hypertension are increasing for the
+reasons which have been given in another chapter. There can be no doubt
+that when these conditions are recognized long before symptoms would
+naturally supervene, men and women would not only live longer but also
+die more comfortably and many very likely would be carried off by some
+disease having no relationship whatever to arteriosclerosis. Slight
+enlargement of the heart downward and to the left, accentuation of the
+second aortic sound at the base, a full pulse, arteries which are
+palpably thickened, increased blood pressure are signs to which
+attention must be paid.
+
+When the peripheral arteries are palpable they are not always sclerosed.
+The radial artery, the one usually palpated, may lie very close to the
+bone in a thin person. Under these conditions the artery can be easily
+felt. It is better then to palpate for the brachial as it lies beneath
+the inner edge of the biceps muscle. Should this artery be felt then
+very probably sclerosis is present. Opinion as to whether or not
+sclerosis is present, when it is slight, may differ. It is difficult at
+times to say definitely. Should such be the case the applicant should be
+most carefully questioned as to his family and past history, the heart
+should be carefully outlined by percussion and the blood pressure should
+be taken, both the systolic and diastolic pressures. The urine should be
+examined with particular care. I am aware that the average examination
+for life insurance is not made with the care which is bestowed upon a
+patient. Yet I see no reason why the same attention to detail should
+not be given in one as in the other. The examination of the great
+majority of applicants can he made in a short time, as there is no
+question of latent chronic disease. When the exception turns up he
+should be given a searching examination and a full report should be sent
+to the Medical Director. Only in this way will it be possible to weed
+out the undesirable risks.
+
+On the surface it does not seem to require any great diagnostic acumen
+to be a life insurance examiner. In the old days of many of the
+companies there were no examiners. The applicant was brought before the
+president or other appointed official and he was passed or rejected on
+his general appearance. This has changed, and now the medical department
+with its scores of examiners in the field is a well organized
+department.
+
+It seems to me that the examiner should be an exceedingly able
+diagnostician and prognosticator. There is no telling when he may be
+called upon to pass judgment on a borderline case. From personal
+experience I know how difficult it is to make a decision in some cases.
+These suspicious cases after a careful examination had better be passed
+by the examiner and a supplementary report sent to the medical director
+containing unbiased details. But no applicant with readily palpable
+arteries, even though the blood pressure be normal, should be considered
+a first class insurance risk.
+
+The question of the value of the diastolic pressure reading in
+examinations for life insurance is not yet settled to the satisfaction
+of all medical directors. Certain medical directors with clinical
+experience behind them, lay great stress on the increased diastolic
+pressure and consider a persistent diastolic of 100 mm. really more
+significant as an indication of hypertension than a systolic pressure of
+160 mm. Other directors pay little or no attention to the diastolic
+reading. Should an applicant show a systolic above the average normal on
+several successive readings, he is declined. When one takes into
+consideration the psychic effect of knowing that he is being examined
+for high blood pressure, it seems unfair to refuse insurance on such
+grounds as is constantly done.
+
+Up to the present there are no extensive series of life-expectancy
+tables in which hundreds of thousands of cases are analyzed from the
+diastolic pressure values. There are many such tables for the systolic
+pressures alone. In the tabulation of such statistics one must not lose
+sight of the important fact that the figures are taken by thousands of
+men of varying capacity and different degrees of intelligence. Such
+studies to be of any real value must be taken from records made at the
+home offices by capable men. We shall await these tables with interest.
+In the meantime we must be permitted to have the impression that the
+diastolic pressure has been much neglected. This has no doubt been due
+to the difficulty of measuring it with any degree of accuracy. Now with
+the auscultatory method and the correct place to read the diastolic
+pressure the results of blood pressure estimations should begin to have
+some value for statistical data.
+
+Clinically the diastolic is probably more important than the systolic.
+Until proof is brought to the contrary we shall believe that in life
+insurance examinations it has the same importance.
+
+
+
+
+CHAPTER XV
+
+PRACTICAL SUGGESTIONS
+
+
+The time spent in obtaining a careful history of a case is time well
+spent. Often the diagnosis can be made from the history alone, the
+physical examination merely adding confirmation to the data already
+obtained.
+
+The younger the patient who has arteriosclerosis, the more probable is
+it that syphilis is the etiologic factor. A denial of infection should
+have little weight if the history of possible exposure is present.
+Miscarriages in a woman should arouse the suspicion of lues in her
+husband. The complement-fixation reaction will often clear up an
+apparently obscure diagnosis.
+
+There are various ways of examining a patient but there is only one
+right way; the examination should be made on the bare skin. However
+skillful one may be in the art of physical diagnosis, he can gather few
+accurate data by examining over the clothes even if he use a
+phonendoscope.
+
+The immoderate eater is laying up for himself a wealth of trouble at the
+time when he can least afford to bear it. The ounce of advice in time is
+worth more to him than the pounds of medicine later.
+
+It is a wise maxim never to drive a horse too far. Apply that to the
+human being and the rule holds equally well.
+
+There may be no symptoms in a case of advanced arteriosclerosis. Do not
+on that account neglect to advise a patient in whom the disease is
+accidentally discovered.
+
+Many a man owes a debt of gratitude to the life insurance examiner. He
+rarely feels grateful.
+
+When a competent ophthalmologist refers a case to a general practitioner
+with the statement that he believes from the appearance of the fundus of
+the eye that arteriosclerotic changes are present over the body, the
+case should be most carefully examined. The earliest diagnoses are not
+infrequently made by the ophthalmologist.
+
+It is the part of wisdom never to have such a firmly preconceived idea
+of the diagnosis that facts observed are perverted in order to fit into
+the diagnosis. Let the facts speak for themselves.
+
+Beware of the snap diagnosis. Even in a case of well-marked
+arteriosclerosis when the diagnosis seems to be written in large letters
+all over the patient, go through the routine. Nine times out of ten this
+may seem needless. The tenth time it saves your conscience and
+reputation. Always consider that you are examining a tenth case.
+
+Gradual loss of weight in a person over fifty years old should arouse
+the suspicion of arteriosclerosis.
+
+Do not call the nervous symptoms displayed by a middle-aged man or woman
+neurasthenia until you have ruled out all organic causes, particularly
+arteriosclerosis.
+
+When palpating the radial artery, always use both hands according to the
+method already described. Pay attention to the superficial or deep
+situation of the artery.
+
+The examination of one specimen of urine does not give much information,
+especially if it should be found to contain no abnormal elements. Fairly
+accurate data may be gathered from the mixed night and morning urine;
+most accurate data from the twenty-four hour specimen. To be of any real
+value there should be frequent examinations of the day's excretion.
+
+In measuring the day's output a good rule is as follows: begin to
+collect urine after the first morning's micturition and collect all
+including the first quantity passed the next morning. It is best to
+examine the centrifugated urine for casts even though no albumin be
+present. It is useless to look for casts in an alkaline urine.
+
+Casts are not infrequently found in chemically normal urine from a
+middle-aged patient. Other things being normal, the finding has no
+significance. The kidneys must be carefully tested functionally.
+
+Blood pressure readings should always be taken with the patient in the
+same posture at every estimation. At the first examination it is
+advisable to take readings from both brachial arteries. Let the patient
+sit comfortably and relax all muscles.
+
+Differentiate as soon as possible between the uncompensated heart caused
+by valvular disease and that caused by arteriosclerosis. There is a
+difference in prognosis. Both give the same symptoms, and are treated
+similarly until compensation returns; thereafter the management of the
+two forms is different.
+
+Aortic incompetence that comes on late in life is generally the result
+of curling of the free margins of the valves caused by syphilitic
+arteriosclerosis. Prognosis is grave because of the fact that the heart
+muscle also is the seat of degenerative changes and compensatory
+hypertrophy is established with difficulty.
+
+When laying down a regime for a patient, consider his disposition, and
+individualize the treatment. Remember that exercise is an essential
+feature of the hygiene of the patient's life but do not forget to be
+explicit about the amount and character of the permissible exercise.
+
+In the prophylaxis of arteriosclerosis, a rational mode of living is the
+all-important factor. As a rule, the less meat one eats, the less is the
+liability of arterial degeneration as age advances. The exceptions to
+this rule are many, and probably depend upon the character of the "vital
+rubber" with which the individual begins life.
+
+The diet in well-marked cases of arteriosclerosis should be carefully
+selected with regard to its nutritive and non-irritating character.
+Animal proteins should be sparingly used. Milk should have an important
+place in the dietary.
+
+No drug relieves the pain of uncomplicated aneurysm as surely as iodide
+of potassium.
+
+Iodides frequently upset the stomach. Be cautious in the use of them.
+The irritable stomach may turn the scales against your patient.
+
+Use cardiac stimulants with care and judgment. If all the valuable
+ammunition is used up at first, the fight will be lost.
+
+Use digitalis with especial care. Its chief usefulness is in steadying
+the decompensated heart, improving the conduction of impulses, and
+increasing the tone of the cardiac muscle. _It should never be given to
+patients with very slow pulses, the subjects of Stokes-Adams syndrome._
+Digitalis has been found to produce partial to complete heart block when
+therapeutically administered.
+
+Remember that in the uncompensated heart morphine not only eases the
+oppressive dyspnea, but also steadies and stimulates the heart.
+
+See to it that the patient has a daily movement of the bowels. In the
+early stage try the effect of liquid paraffin or of the mineral waters
+such as Pluto, or Hunyadi Janos, or artificial Carlsbad salts (Sprudel
+salts). These last can be made as follows: Sodium chloride, ounce I;
+sodium bicarbonate, ounce II; sodium sulphate, ounce IV. Take two
+tablespoonsful of this in a glass of hot water before breakfast. Should
+these not succeed, assist the action of the drugs by the use of enemata.
+The pill of aloin, strychnine sulphate, and extract of cascara, with the
+addition of a small quantity of hyoscyamus, is a mild tonic purgative.
+In cases of constipation with high tension, there is no drug as valuable
+as calomel or one of the other mercurials given occasionally.
+
+Never give Epsom salts unless copious watery stools are desired to
+deplete effusion into the serous cavities or into the subcutaneous
+tissue.
+
+Chronic constipation increases the gravity of the prognosis.
+
+In case of suppression of urine and anasarca, hot air packs may be of
+value. The patient may be wrapped in a hot wet sheet and covered with
+blankets. I do not believe in administering pilocarpine to assist the
+sweating.
+
+Remember to treat the patient and not the disease. The careful hygienic
+and dietetic treatment, combined with the least amount of drugging, is
+the best and most rational method of treatment.
+
+
+
+
+INDEX
+
+
+ A
+
+ Abdominal symptoms, 201
+
+ Aconite in treatment, 242
+
+ Acquired arteriosclerosis, 159
+
+ Adami, effect of syphilis in aorta, 45
+
+ Adventitia, 28
+
+ Age in arteriosclerosis, 161
+
+ Albuminuria, 221
+
+ Albutt's classification of arteriosclerosis, 186
+
+ Alcohol, 166, 228, 235
+
+ Anatomy, 25
+
+ Angina abdominalis, 201, 216
+ pectoris, 197, 216
+ pseudo, 216
+
+ Angiosclerosis, 26, 64
+
+ Aorta, 27
+ anatomical lesions in, 33
+ Aschoff on, 35
+ normal, 41
+ syphilis in, 44
+ thoracic, 29
+ thoracic and abdominal, arteriosclerosis of, 39
+ velocity of blood in, 66
+
+ Aortic incompetence, 61, 258
+ stenosis, 60
+
+ Aortitis, acute, 165
+
+ Arcus senilis, 191
+
+ Arrhythmia, tonal, 92, 102
+
+ Arterial pressure, 85
+ symptoms, 189
+
+ Arteries, 29
+ examination of, 172, 177
+ general structure of, 27
+ large, 30
+ adventitia of, 30
+ palpable, 189
+ pulmonary, arteriosclerosis of, 63
+
+ Arteriocapillary fibrosis, 26
+
+ Arteriosclerotic endocarditis, 60, 219
+
+ Artery, coronary, cross-section of, 36
+ pulmonary, 209
+ radial, 29
+
+ Aschoff on aorta, 35
+
+ Atheroma, simple, 32
+
+ Atheromatous abscess, 38
+
+ Auricular fibrillation, 133
+ flutter, 131
+
+ Auscultation, 176
+
+ Auscultatory blood pressure phenomenon, 90
+ method of taking blood pressure, 83
+ percussion, 175
+
+
+ B
+
+ Balneotherapy, 233
+
+ Basch's blood pressure instrument, 70
+
+ Blood, circulation of, 65
+ velocity of, 65
+ in animals, 66
+ in aorta, 66
+ in capillaries, 66
+ viscosity of, 68
+
+ Blood pressure, 68
+ auscultatory method of taking, 83
+ clinical applications of, 147
+ diurnal variations of, 102
+ drugs influencing, 120
+ estimation of, 179
+ in cancer, 118
+ in collapse, 118
+ in exercise, 105
+ in head injuries, 148
+ in hemorrhages, 105, 118, 148
+ in infectious diseases, 153
+ in kidney diseases, 155
+ in meningitis, 118
+ in obstetrics, 152
+ in pulmonary tuberculosis, 119
+ in shock, 105, 148
+ in surgery, 147
+ in typhoid fever, 118, 154
+ in valvular heart disease, 155
+ increase of, 55
+ instruments, 70
+ Brown's, 74
+ Cook's, 71
+ Erlanger's, 72
+ Faught's, 75, 80
+ Hill and Barnard's, 70
+ Hirschfelder's, 73
+ K. Vierordt's, 70
+ Marcy's, 70
+ Potain's, 70
+ Riva Rocci's, 70
+ Roger's, 77
+ Sanborn's, 80
+ Stanton's, 72
+ technique of, 80
+ "Tycos," 77
+ v. Basch's, 70
+ v. Recklinghausen's, 76
+ mechanism of, 55
+ normal variations of, 88
+ phenomenon, auscultatory, 90
+ precautions when estimating, 181
+ value of, 181
+
+ Bowman's capsules, sclerosis of, 62
+
+ Brain, changes in, 62
+
+ Brown atrophy, 60, 118, 201
+
+
+ C
+
+ Calcification of media, 43, 59
+
+ Cancer, blood pressure in, 118
+
+ Capillaries, anatomy of, 27, 31
+
+ Capillary pulse, 67
+
+ Cardiac dullness, 172
+ irregularities in arteriosclerosis, 131
+ symptoms, 195
+
+ Cerebral symptoms, 203
+
+ Circulation of blood, 65
+ physiology of, 65
+
+ Cirrhosis of liver, 64, 216
+
+ Classification of arteriosclerosis, 32, 37
+ Allbutt's, 186
+
+ Collapse, blood pressure in, 118
+
+ Congenital arteriosclerosis, 157
+
+ Cook's blood pressure instrument, 71
+
+ Cor bovinum, 116
+
+ Coronary artery, cross section of, 36
+
+ Corpus luteum, 241
+
+
+ D
+
+ Definition of arteriosclerosis, 26
+
+ Diabetes mellitus, 216
+
+ Diagnosis, 210
+ differential, 215
+ early, 210
+ ophthalmic examination in, 214
+
+ Diastolic pressure, 69, 83, 85, 94
+ importance of, 97
+
+ Dicrotic pulse, 123
+
+ Dietetic treatment, 235
+
+ Differential diagnosis, 166, 215
+
+ Diffuse arteriosclerosis, 32, 37, 38, 57
+
+ Digitalis in treatment, 246, 259
+
+ Diuretin in treatment, 246
+
+ Drug intoxications, 166
+
+ Drugs influencing blood pressure, 105, 120
+
+ Ductless glands, 171
+
+ Dullness, cardiac, 172
+
+ Dyspeptic symptoms, 184
+
+ Dyspnea, 184
+ treatment of, 248
+
+
+ E
+
+ Electrocardiogram, 126
+
+ Embolism, 59
+
+ Endarteritis deformans, 47
+ obliterans, 46
+
+ Endocarditis, arteriosclerotic, 60, 219
+
+ Endothelial lining, 27
+ tubes, 31
+
+ Epistaxis, 184, 221
+
+ Erlanger's blood pressure instrument, 72
+
+ Erythromelalgia, 192, 208
+
+ Estimation of blood pressure, 179
+
+ Etiology, 157
+
+ Examination of arteries, 172, 177
+ of heart, 172
+ of urine, 257
+
+ Exercise, blood pressure in, 105
+ in prophylaxis, 225
+ in treatment, 230
+
+ Experimental arteriosclerosis, 50
+
+ Extrasystole, 138
+
+
+ F
+
+ Faught's blood pressure instrument, 75, 80
+
+ Fibrillation, auricular, 133
+ ventricular, 138
+
+ Fibrolysin in treatment, 243
+
+ Fingernail palpation, 178
+
+ Finger tip palpation, 179
+
+ Flutter, auricular, 131
+
+ Food poisons in arteriosclerosis, 163
+
+
+ G
+
+ Gibson's law, 154
+
+
+ H
+
+ "H" wave, 126
+
+ Habits, personal, 234
+
+ Head injuries, blood pressure in, 148
+
+ Headache, 184
+ treatment of, 248
+
+ Heart block, 140
+ boundaries, 172
+ examination of, 172
+ hypertrophy of, 60
+ physical examination of, 172
+ stimulants, 243, 246, 259
+ symptoms, 188
+
+ Hemorrhages, blood pressure in, 118
+
+ Henle, membrane of, 29
+
+ Hill and Barnard's blood pressure instrument, 70
+
+ Hirschfelder's blood pressure instrument, 73
+
+ His, bundle of, 141, 197
+
+ Hygienic treatment, 230
+
+ Hyperpietic arteriosclerosis, 186
+
+ Hypertension, 60, 106, 169, 185, 249
+ cause of arteriosclerosis, 159
+ classification of cases, 112
+
+ Hypertrophy of left ventricle, 58
+
+ Hypotension, 117
+
+
+ I
+
+ Incompetence, aortic, 61, 258
+
+ Indicanuria, 167
+
+ Infants, arteriosclerosis in, 158
+
+ Infectious diseases in arteriosclerosis, 163
+ blood pressure in, 153
+
+ Insomnia, treatment of, 248
+
+ Intermittent claudication, 192, 208
+ treatment of, 247
+
+ Intoxications, chronic drug, 166
+
+ Intracranial tension, 105
+
+ Involutionary arteriosclerosis, 187
+
+ Iodides in treatment, 238, 247, 259
+
+
+ K
+
+ Kidney diseases, blood pressure in, 155
+
+ Kidneys, sclerosis of, 61, 170
+
+
+ L
+
+ Life insurance, relation to, 249
+
+ Light percussion, 174
+ touch palpation, 175
+
+ Liver, cirrhosis, 64, 216
+
+ Local symptoms, 207
+
+
+ M
+
+ Marey's blood pressure instrument, 70
+
+ Maximum pressure, 85, 94
+
+ Mean pressure, 85
+
+ Media, calcification of, 43, 59
+
+ Medicinal treatment, 238
+
+ Meningitis, blood pressure in, 118
+
+ Mental strain, 168
+
+ Mesaortitis, 45, 47, 49, 165
+
+ Mesentery, cross-section of small artery in, 56
+
+ Milk diet, 237
+
+ Minimum pressure, 86, 94
+
+ Moenckeberg type of arteriosclerosis, 43
+
+ Morphine in treatment, 243
+
+ Mosenthal test meal, 221
+
+ Muscular overwork, 169
+
+
+ N
+
+ Nervous symptoms, 191
+
+ Nitrites in treatment, 240
+
+ Nitroglycerin in treatment, 241
+
+ Nodular arteriosclerosis, 32, 37
+
+ Normal blood pressure variation, 88
+
+
+ O
+
+ Obstetrics, blood pressure in, 152
+
+ Occupation in arteriosclerosis, 162
+
+ Ocular symptoms, 190
+
+ Ophthalmic examination, importance in early diagnosis, 214, 256
+
+ Orthodiagraph, 173
+
+ Overeating, 167, 212, 225, 235
+
+ Overwork, muscular, 169
+
+
+ P
+
+ "P" wave, 129
+
+ "P-R" interval, 130
+
+ Palpable arteries, 189
+
+ Palpation, 174, 180
+ fingernail, 178
+ finger tip, 179
+ light touch, 175
+
+ Pathology, 32
+
+ Percussion, 174
+ auscultatory, 175
+ light, 174
+
+ Peripheral symptoms, 207
+
+ Personal habits, 234
+
+ Phlebosclerosis, 64
+
+ Phthalein test, 221
+
+ Physical signs, 183
+
+ Physiology of the circulation, 65
+
+ Potain's blood pressure instrument, 70
+
+ Practical suggestions, 256
+
+ Pressure, arterial, 85
+ ausculatory method of determining, 83
+ diastolic, 83, 94
+ estimation of, 179
+ in surgery, 147
+ maximum, 85, 94
+ normal variations, 88
+ pulse, 83, 85, 87, 100
+ systolic, 82, 85
+ technique, 80
+ venous, 120
+
+ Prognosis, 218
+
+ Prophylaxis, 224
+ exercise in, 225
+
+ Pseudo angina pectoris, 216
+
+ Pulmonary artery, 209
+ arteriosclerosis of, 63
+ tuberculosis, blood pressure in, 119
+
+ Pulse, 123
+ capillary, 67
+ deficit, 135
+ dicrotic, 123
+ in arteriosclerosis, 123
+ pressure, 69, 83, 85, 87, 100
+ rate, 69
+ venous, 123
+
+ Purgatives in treatment, 244, 259
+
+ Pyrosis, 184
+
+
+ Q
+
+ "Q R S" complex, 129
+
+
+ R
+
+ Rabbits, lesions produced experimentally in, 50
+
+ Race in arteriosclerosis, 161
+
+ Radial artery, 29
+
+ Radials, sclerosis of, 43
+
+ Raynaud's disease, 192, 207
+
+ Recklinghausen's blood pressure instrument, 76
+
+ Renal disease, 169
+ symptoms, 199
+
+ Rest in treatment, 242
+
+ Riva-Rocci's blood pressure instrument, 70
+
+ Rogers' blood pressure instrument, 77
+
+
+ S
+
+ Sanborn's blood pressure instrument, 80
+
+ Scaphoid scapula, 158
+
+ Schwellungsperkussion, 174
+
+ Sclerosis of veins, 64
+
+ Senile arteriosclerosis, 32, 37, 43, 59
+
+ Sex in arteriosclerosis, 161
+
+ Shock, blood pressure in, 105, 148
+
+ Spinal symptoms, 205
+
+ Spirochaeta pallida, 45
+
+ Stanton's blood pressure instrument, 72
+
+ Stenosis, aortic, 60
+
+ Stokes-Adams syndrome, 197
+
+ Stomach, ulcer of, 216
+
+ Strain hypertrophy, 47, 54, 55
+
+ Surgery, blood pressure in, 147
+
+ Symptomatic treatment, 245
+
+ Symptoms, 183
+ abdominal, 201
+ arterial, 189
+ cardiac, 195
+ cerebral, 203
+ dyspeptic, 184
+ dyspnea, 184
+ general, 183
+ headache, 184
+ heart, 188
+ local, 207
+ nervous, 191
+ ocular, 190
+ peripheral, 207
+ pyrosis, 184
+ renal, 199
+ special, 194
+ spinal, 205
+ vertigo, 184
+ visceral, 201
+
+ Syphilis, 165
+ in aorta, 44
+
+ Syphilitic arteriosclerosis, 37
+
+ Systolic pressure, 69, 82, 85, 94
+ importance of, 97
+
+
+ T
+
+ "T" wave, 130
+
+ Technique of blood pressure instruments, 80
+
+ Thayer and Fabyan, 34
+
+ Theocin, 247
+
+ Thoma on arteriosclerosis, 33
+
+ Thoracic aorta, 29
+
+ Thyroid extract in treatment, 239
+
+ Tobacco, 167, 212, 234
+
+ Tonal arrhythmia, 92, 102
+
+ Toxic arteriosclerosis, 186
+
+ Treatment, 229
+ aconite in, 242
+ balneotherapy in, 233
+ corpus luteum, 241
+ dietetic, 235
+ digitalis in, 246, 259
+ diuretin in, 246
+ exercise in, 230
+ fibrolysin in, 243
+ heart stimulants in, 243
+ hygienic, 230
+ iodides in, 238, 247, 259
+ medicinal, 238
+ morphine in, 243
+ nitrites in, 240
+ nitroglycerin in, 241
+ of dyspnea, 248
+ of headache, 248
+ of insomnia, 248
+ of intermittent claudication, 247
+ personal habits in, 234
+ purgatives in, 244, 259
+ rest in, 242
+ symptomatic, 245
+ theocin in, 247
+ thyroid extract in, 239
+ Trunecek's serum in, 243
+ venesection in, 242
+ veratrum viride in, 242
+
+ Trunecek's serum in treatment, 243
+
+ Tuberculosis, blood pressure in, 119
+
+ Tunica intima, 28
+ media, 28
+
+ "Tycos" blood pressure instrument, 77
+
+ Typhoid fever as cause of arteriosclerosis, 164
+ blood pressure in, 118
+
+
+ U
+
+ Ulcer of stomach, 216
+
+ Urine, examination of, 257
+ suppression of, 259
+
+
+ V
+
+ Valvular heart disease, blood pressure in, 155
+
+ Vasa vasorum, 29
+
+ Veins, anatomy of, 30
+ sclerosis of, 64
+
+ Velocity of blood in animals, 66
+ of blood in aorta, 66
+
+ Venesection in treatment, 242
+
+ Venous pressure, 120
+ pulse, 123
+
+ Ventricle, left, hypertrophy of, 58
+
+ Ventricular fibrillation, 138
+
+ Veratrum viride in treatment, 242
+
+ Vertigo, 184
+
+
+ * * * * *
+
+
+Transcriber's Notes: Irregular hyphenation has been preserved, as in
+blood pressure and blood-pressure. Both "Hg" and "Hg." appear.
+
+Minor typographical errors and inconsistencies have been silently
+normalized.
+
+The original printed list of illustrations shows the original
+locations; they have been moved closer to their discussion area
+in the text to not interrupt the flow of reading.
+
+Page 244 Prescription symbol is replaced with R_{x}
+
+Page 259 Apothecaries ounce symbol replaced with "ounce"
+
+
+
+
+
+End of the Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
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+<body>
+
+
+<pre>
+
+The Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever. You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Arteriosclerosis and Hypertension:
+ with Chapters on Blood Pressure, 3rd Edition.
+
+Author: Louis Marshall Warfield
+
+Release Date: October 12, 2011 [EBook #37675]
+
+Language: English
+
+Character set encoding: ISO-8859-1
+
+*** START OF THIS PROJECT GUTENBERG EBOOK ARTERIOSCLEROSIS AND HYPERTENSION: ***
+
+
+
+
+Produced by Bryan Ness, Julia Neufeld and the Online
+Distributed Proofreading Team at http://www.pgdp.net (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+</pre>
+
+
+
+
+
+
+<h4><span class="smcap">Erratum</span></h4>
+
+
+<p>Page 75, Figure shown is not the Brown sphygmomanometer
+described in the text, but the Baumanometer
+manufactured by W. A. Baum Co., Inc.,
+New York. It is claimed that the Baumanometer
+is made with particular care and hence the readings
+are said to be more accurate than other mercury
+instruments. It is apparently a good instrument.
+The author has had no personal experience with it.<br /><br /></p>
+<hr style="width: 45%;" />
+<h1>
+ARTERIOSCLEROSIS<br />
+<br />
+AND<br />
+<br />
+HYPERTENSION</h1>
+<h3>
+With Chapters on Blood Pressure<br />
+<br />
+BY<br />
+
+</h3>
+
+
+<h2>LOUIS M. WARFIELD, A.B., M.D., (Johns Hopkins),<br />
+F.A.C.P.</h2>
+<div class="center"><br />
+<br />
+FORMERLY PROFESSOR OF CLINICAL MEDICINE, MARQUETTE UNIVERSITY MEDICAL<br />
+SCHOOL; CHIEF PHYSICIAN TO MILWAUKEE COUNTY HOSPITAL; ASSOCIATE<br />
+MEMBER ASSOCIATION AMERICAN PHYSICIANS; MEMBER AMERICAN<br />
+ASSOCIATION PATHOLOGISTS AND BACTERIOLOGISTS;<br />
+AMERICAN MEDICAL ASSOCIATION, ETC., FELLOW<br />
+AMERICAN COLLEGE OF PHYSICIANS<br />
+<br /><br />
+<i>THIRD EDITION</i><br />
+<br /><br />
+ST. LOUIS<br />
+<br />
+C. V. MOSBY COMPANY<br />
+<br />
+1920<br />
+<br />
+</div>
+<hr style="width: 45%;" />
+<div class="center"><span class="smcap">Copyright, 1912, 1920, by C. V. Mosby Company</span><br />
+<br />
+<i>Press of<br />
+C. V. Mosby Company<br />
+St. Louis</i><br />
+<br />
+</div>
+<hr style="width: 65%;" />
+
+<div class="center">TO<br />
+<br />
+MY MOTHER<br />
+<br />
+THIS VOLUME IS AFFECTIONATELY<br />
+<br />
+DEDICATED<br />
+</div>
+
+<hr style="width: 65%;" />
+
+<p><span class="pagenum"><a name="Page_15" id="Page_15">[15]</a></span></p>
+<h2>PREFACE TO THIRD EDITION</h2>
+
+
+<p>Several years have elapsed since the appearance of the
+second edition of this book. During this time there has
+been considerable experimentation and much writing on
+arteriosclerosis. The total of all work has not been to add
+very much to our knowledge of the etiology of arterial degeneration.
+Points of view and opinions change from time
+to time. It is so with arteriosclerosis. In this edition arteriosclerosis
+is not regarded as a disease with a definite
+etiologic factor. Rather it is looked upon as a degenerative
+process affecting the arteries following a variety of causes
+more or less ill defined. It is not considered a true disease.
+Possibly syphilitic arteritis may be viewed as an entity, the
+cause is known and the lesions are characteristic.</p>
+
+<p>Much new material and many new figures have been
+added to this edition. Some rearranging has been done.
+The chapter on Blood Pressure has been much expanded
+and some original observations have been included. The
+literature has been selected rather than indiscriminately
+quoted. Much that is written on the subject is of little
+value.</p>
+
+<p>It has always seemed to the author that there is not
+enough of the personal element in medical writings. At the
+risk of being severely criticized, he has attempted to make
+this book represent largely his own ideas, only here and
+there quoting from the literature.</p>
+
+<p>New chapters on Cardiac Irregularities Associated with
+Arteriosclerosis, and Blood Pressure in Its Clinical Application
+have been added.</p>
+
+<p>The fact that the book has passed through two editions is
+very gratifying and seems to show that it has met with favor.
+The author takes this opportunity of thanking those
+who have loaned him illustrations. Wherever figures are
+borrowed due credit is given.</p>
+
+<p><span class="pagenum"><a name="Page_16" id="Page_16">[16]</a></span>It is hoped that the kind of reception accorded to the first
+and second editions will also not be withheld from this present
+edition.</p>
+
+<div class="signature"><span class="smcap">Louis M. Warfield.</span></div>
+<p>
+Milwaukee, Wisc.
+</p>
+
+
+
+<hr style="width: 65%;" />
+<h2>PREFACE TO THE SECOND EDITION</h2>
+
+
+<p>In this second edition so many changes and additions
+have been made that the book is practically a new one. All
+the chapters which were in the previous edition have been
+carefully revised. Two chapters, "Pathology" and "Physiology,"
+have been completely rewritten and brought up to
+date. It was thought best to add some references for those
+who had interest enough to pursue the subject further.
+These references have been selected on account of the readiness
+with which they may be procured in any library, public
+or private. Two new chapters have been added&mdash;one on
+"The Physical Examination of the Heart and Arteries,"
+the other on "Arteriosclerosis in Its Relation to Life Insurance,"
+and it is hoped that these will add to the practical
+value of the book.</p>
+
+<p>Arteriosclerosis can scarcely be considered apart from
+blood pressure, and in the view expressed within, with
+which some may not concur, high tension is considered to be
+a large factor in the production of arteriosclerosis. As the
+data on blood pressure have increased, the importance of it
+has become more evident. The chapter on "Blood Pressure"
+has been wholly rewritten, expanded so as to give
+a comprehensive grasp of the essential features, and several
+illustrations have been added in order to elucidate the text
+more fully. The chief objects in view were to make clear
+to the physician the technique and the necessity for estimating
+both systolic and diastolic pressures.</p>
+
+<p>The author is grateful for the kindly reception accorded
+the first edition. No one is more keenly aware of the imperfections<span class="pagenum"><a name="Page_17" id="Page_17">[17]</a></span>
+than he. The necessity for a second edition is
+taken to mean that the book has found a place for itself
+and has been of use to some.</p>
+
+<p>The author hopes that this new edition will fulfill adequately
+the purpose for which he prepared the book&mdash;namely,
+as a practical guide to the knowledge and appreciation
+of a most important and exceedingly common
+disease.</p>
+
+<div class="signature"><span class="smcap">Louis M. Warfield.</span></div>
+
+<p>Milwaukee, May, 1912.<br />
+</p>
+
+
+
+<hr style="width: 65%;" />
+<h2>PREFACE TO THE FIRST EDITION</h2>
+
+
+<p>It is hoped that this small volume may fill a want in the
+already crowded field of medical monographs. The author
+has endeavored to give to the general practitioner a
+readable, authoritative essay on a disease which is especially
+an outcome of modern civilization. To that end all
+the available literature has been freely consulted, and the
+newest results of experimental research and the recent
+ideas of leading clinicians have been summarized. The author
+has supplemented these with results from his own
+experience, but has thought it best not to burden the contents
+with case histories.</p>
+
+<p>The stress and strain of our daily life has, as one of
+its consequences, early arterial degeneration. There can
+be no doubt that arterial disease in the comparatively
+young is more frequent than it was twenty-five years ago,
+and that the mortality from diseases directly dependent
+on arteriosclerotic changes is increasing. Fortunately, the
+almost universal habit of getting out of doors whenever
+possible, and the revival of interest in athletics for persons
+of all ages, have to some extent counteracted the tendency
+to early decay. Nevertheless, the actual average prolongation
+of life is more probably due to the very great
+reduction in infant mortality and in deaths from infectious
+and communicable diseases.</p>
+
+<p><span class="pagenum"><a name="Page_18" id="Page_18">[18]</a></span>The wear and tear on the human organism in our modern
+way of living is excessive. Hard work, worry, and
+high living all predispose to degenerative changes in the
+arteries, and so bring on premature old age. The author
+has tried to emphasize this by laying stress on the prevention
+of arteriosclerosis rather than on the treatment of the
+fully developed disease.</p>
+
+<p>No bibliography is given, as this is not intended as a
+reference book, but rather as a guide to a better appreciation
+and understanding of a most important subject. It
+has been difficult to keep from wandering off into full discussions
+of conditions incident to and accompanied by
+arteriosclerosis, but, in order to be clear in his statements
+and complete in his descriptions, the author has to invade
+the fields of heart disease, kidney disease, brain disease,
+etc. It is hoped, however, that these excursions will serve
+to show how intimately disease of the arteries is bound
+up with diseases of all the organs and tissues of the body.</p>
+
+<p>Some authors have been named when their opinions
+have been given. Thanks are extended also to many others
+to whom the writer is indebted, but of whom no individual
+mention has been made.</p>
+
+<p>The author also takes this opportunity of expressing
+his appreciation of the kindness of Dr. D. L. Harris, who
+took the microphotographs, and to the publishers for their
+unfailing courtesy and consideration.</p>
+
+<div class="signature">
+<span class="smcap">Louis M. Warfield.</span></div>
+
+<p>St. Louis, August, 1908.<br />
+</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_19" id="Page_19">[19]</a></span></p>
+<h2>CONTENTS</h2>
+
+<blockquote>
+
+<p><span class="pgnum-contents"><span class="smcap">page</span></span></p>
+
+<h3><a href="#CHAPTER_I">CHAPTER I.</a></h3>
+
+<p><span class="smcap">Anatomy</span><span class="pgnum-contents">25</span></p>
+
+<p class="hanging">Introduction, 25; Definition, 26; General Structure of the Arteries,
+27; Arteries, 29; Veins, 30; Capillaries, 31.</p>
+
+<h3><a href="#CHAPTER_II">CHAPTER II.</a></h3>
+
+<p><span class="smcap">Pathology</span><span class="pgnum-contents">32</span></p>
+
+<p class="hanging">Syphilitic Aortitis, 44; Experimental Arteriosclerosis, 50; Arteriosclerosis
+of the Pulmonary Arteries, 63; Sclerosis of the Veins, 64.</p>
+
+<h3><a href="#CHAPTER_III">CHAPTER III.</a></h3>
+
+<p><span class="smcap">Physiology of the Circulation</span><span class="pgnum-contents">65</span></p>
+
+<p class="hanging">Blood Pressure, 68; Blood Pressure Instruments, 70; Technic, 80;
+Arterial Pressure, 85; Normal Pressure Variations, 88; The Auscultatory
+Blood Pressure Phenomenon, 90; The Maximum and Minimum
+Pressures, 94; Relative Importance of the Systolic and Diastolic
+Pressures, 97; Pulse Pressure, 100; Blood Pressure Variations,
+102; Hypertension, 106; Hypotension, 117; The Pulse, 123; The
+Venous Pulse, 123; The Electrocardiogram, 126.</p>
+
+<h3><a href="#CHAPTER_IV">CHAPTER IV.</a></h3>
+
+<p><span class="smcap">Important Cardiac Irregularities Associated With Arteriosclerosis</span> <span class="pgnum-contents">13</span></p>
+
+<p class="hanging">Auricular Flutter, 131; Auricular Fibrillation, 133; Ventricular
+Fibrillation, 138; Extrasystole, 138; Heart Block, 140.</p>
+
+<h3><a href="#CHAPTER_V">CHAPTER V.</a></h3>
+
+<p><span class="smcap">Blood Pressure in Its Clinical Applications</span><span class="pgnum-contents">147</span></p>
+
+<p class="hanging">Blood Pressure in Surgery, 147; Head Injuries, 148; Shock and
+Hemorrhage, 148; Blood Pressure in Obstetrics, 152; Infectious
+Diseases, 153; Valvular Heart Disease, 155; Kidney Disease, 155;
+Other Diseases, Liver, Spleen, Abdomen, etc., 156.</p>
+
+<h3><a href="#CHAPTER_VI">CHAPTER VI.</a></h3>
+
+<p><span class="smcap">Etiology</span><span class="pgnum-contents">157</span></p>
+
+<p class="hanging">Congenital Form, 157; Acquired Form, 159; Hypertension, 159;
+Age, Sex, Race, 161; Occupation, 162; Food Poisons, 163; Infectious
+Diseases, 163; Syphilis, 165; Chronic Drug Intoxications, 166;
+Overeating, 167; Mental Strain, 168; Muscular Overwork, 169;
+Renal Disease, 169; Ductless Glands, 171.</p>
+<p><span class="pagenum"><a name="Page_20" id="Page_20">[20]</a></span></p>
+<h3><a href="#CHAPTER_VII">CHAPTER VII.</a></h3>
+
+<p><span class="smcap">The Physical Examination of the Heart and Arteries</span><span class="pgnum-contents">172</span></p>
+
+<p class="hanging">Heart Boundaries, 172; Percussion, 174; Auscultation, 176; The
+Examination of the Arteries, 177; Estimation of Blood Pressure,
+179; Palpation, 180; Precautions When Estimating Blood Pressure,
+181; The Value of Blood Pressure, 181.</p>
+
+<h3><a href="#CHAPTER_VIII">CHAPTER VIII.</a></h3>
+
+<p><span class="smcap">Symptoms and Physical Signs</span><span class="pgnum-contents">183</span></p>
+
+<p class="hanging">General, 183; Hypertension, 185; The Heart, 188; Palpable Arteries,
+189; Ocular Signs and Symptoms, 190; Nervous Symptoms, 191.</p>
+
+<h3><a href="#CHAPTER_IX">CHAPTER IX.</a></h3>
+
+<p><span class="smcap">Symptoms and Physical Signs</span><span class="pgnum-contents">194</span></p>
+
+<p class="hanging">Special, 194; Cardiac, 195; Renal, 199; Abdominal or Visceral, 201;
+Cerebral, 203; Spinal, 205; Local or Peripheral, 207; Pulmonary
+Artery, 209.</p>
+
+<h3><a href="#CHAPTER_X">CHAPTER X.</a></h3>
+
+<p><span class="smcap">Diagnosis</span><span class="pgnum-contents">210</span></p>
+
+<p class="hanging">Early Diagnosis, 210; Differential Diagnosis, 215; Diseases in Which
+Arteriosclerosis is Commonly Found, 216.</p>
+
+<h3><a href="#CHAPTER_XI">CHAPTER XI.</a></h3>
+
+<p><span class="smcap">Prognosis</span><span class="pgnum-contents">218</span></p>
+
+<h3><a href="#CHAPTER_XII">CHAPTER XII.</a></h3>
+
+<p><span class="smcap">Prophylaxis</span><span class="pgnum-contents">224</span></p>
+
+<h3><a href="#CHAPTER_XIII">CHAPTER XIII.</a></h3>
+
+<p><span class="smcap">Treatment</span><span class="pgnum-contents">229</span></p>
+
+<p class="hanging">Hygienic Treatment, 230; Balneotherapy, 233; Personal Habits,
+234; Dietetic Treatment, 235; Medicinal, 238; Symptomatic Treatment,
+245.</p>
+
+<h3><a href="#CHAPTER_XIV">CHAPTER XIV.</a></h3>
+
+<p><span class="smcap">Arteriosclerosis in Its Relation to Life Insurance</span><span class="pgnum-contents">249</span></p>
+
+<h3><a href="#CHAPTER_XV">CHAPTER XV.</a></h3>
+
+<p><span class="smcap">Practical Suggestions</span><span class="pgnum-contents">256</span></p>
+</blockquote>
+
+
+
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_21" id="Page_21">[21]</a></span></p>
+<h2>ILLUSTRATIONS</h2>
+
+
+
+<div class="center">
+<table border="0" cellpadding="4" cellspacing="0" summary="LIST OF ILLUSTRATIONS">
+<tr><td align="left">FIG.</td><td><span class="smcap">page</span></td></tr>
+<tr><td align="left"><a href="#Cross_section_of_a_large_artery">1. Cross section of a large artery</a></td><td align="right">28</td></tr>
+<tr><td align="left"><a href="#Cross_section_of_a_coronary_artery">2. Cross section of a coronary artery</a></td><td align="right">36</td></tr>
+<tr><td align="left"><a href="#Arteriosclerosis_of_the_thoracic_and_abdominal_aorta">3. Arteriosclerosis of the thoracic and abdominal aorta</a></td><td align="right">39</td></tr>
+<tr><td align="left"><a href="#Arteriosclerosis_of_the_arch_of_the_aorta">4. Arteriosclerosis of the arch of the aorta</a></td><td align="right">40</td></tr>
+<tr><td align="left"><a href="#Normal_Aorta">5. Normal Aorta</a></td><td align="right">41</td></tr>
+<tr><td align="left"><a href="#Radiogram_showing_calcification_of_both_radial_and_ulnar_arteries">6. Radiogram showing calcification of both radial and ulnar arteries</a></td><td align="right">42</td></tr>
+<tr><td align="left"><a href="#Syphilitic_aortitis_of_long_standing">7. Syphilitic aortitis of long standing</a></td><td align="right">44</td></tr>
+<tr><td align="left"><a href="#Diagrammatic_representation_of_strain_hypertrophy">8. Diagrammatic representation of strain hypertrophy</a></td><td align="right">48</td></tr>
+<tr><td align="left"><a href="#Strain_hypertrophy">9. Strain hypertrophy</a></td><td align="right">49</td></tr>
+<tr><td align="left"><a href="#Cross_section_of_small_artery_in_the_mesentery">10. Cross section of small artery in the mesentery</a></td><td align="right">56</td></tr>
+<tr><td align="left"><a href="#Enormous_hypertrophy_of_left_ventricle">11. Enormous hypertrophy of left ventricle</a></td><td align="right">58</td></tr>
+<tr><td align="left"><a href="#Aortic_incompetence_with_hypertrophy_and_dilatation_of_left_ventricle">12. Aortic incompetence with hypertrophy and dilatation of left ventricle</a></td><td align="right">61</td></tr>
+<tr><td align="left"><a href="#Cooks_modification_of_Riva-Roccis_blood_pressure_instrument">13. Cooks modification of Riva-Roccis blood pressure instrument</a></td><td align="right">72</td></tr>
+<tr><td align="left"><a href="#Stantons_sphygmomanometer">14. Stanton's sphygmomanometer</a></td><td align="right">73</td></tr>
+<tr><td align="left"><a href="#The_Erlanger_sphygmomanometer_with_the_Hirschfelder_attachments">15. The Erlanger sphygmomanometer with the Hirschfelder attachments</a></td><td align="right">74</td></tr>
+<tr><td align="left"><a href="#Desk_model_Baumanometer">16. Desk model Baumanometer</a></td><td align="right">75</td></tr>
+<tr><td align="left"><a href="#Faught_blood_pressure_instrument">17. Faught blood pressure instrument</a></td><td align="right">76</td></tr>
+<tr><td align="left"><a href="#Rogers_Tycos_dial_sphygmomanometer">18. Rogers' "Tycos" dial sphygmomanometer</a></td><td align="right">77</td></tr>
+<tr><td align="left"><a href="#Detail_of_the_dial_in_the_Tycos_instrument">19. Detail of the dial in the "Tycos" instrument</a></td><td align="right">78</td></tr>
+<tr><td align="left"><a href="#Faught_dial_instrument">20. Faught dial instrument</a></td><td align="right">79</td></tr>
+<tr><td align="left"><a href="#Detail_of_the_dial_of_the_Faught_instrument">21. Detail of the dial of the Faught instrument</a></td><td align="right">79</td></tr>
+<tr><td align="left"><a href="#The_Sanborn_instrument">22. The Sanborn instrument</a></td><td align="right">80</td></tr>
+<tr><td align="left"><a href="#Method_of_taking_blood_pressure_with_a_patient_in_sitting_position">23. Method of taking blood pressure with a patient in sitting position</a></td><td align="right">81</td></tr>
+<tr><td align="left"><a href="#Method_of_taking_blood_pressure_with_patient_lying_down">24. Method of taking blood pressure with patient lying down</a></td><td align="right">82</td></tr>
+<tr><td align="left"><a href="#Observation_by_the_auscultatory_method_and_a_mercury_instrument">25. Observation by the auscultatory method and a mercury instrument</a></td><td align="right">84</td></tr>
+<tr><td align="left"><a href="#Observation_by_the_auscultatory_method_and_a_dial_instrument">26. Observation by the auscultatory method and a dial instrument</a></td><td align="right">85</td></tr>
+<tr><td align="left"><a href="#Schema_to_illustrate_decrease_in_pressure">27. Schema to illustrate decrease in pressure</a></td><td align="right">86</td></tr>
+<tr><td align="left"><a href="#Chart_showing_the_normal_limits_of_variation_in_systolic_blood_pressure">28. Chart showing the normal limits of variation in systolic blood pressure</a></td><td align="right">89</td></tr>
+<tr><td align="left"><a href="#Tracing_of_auscultatory_phenomena">29. Tracing of auscultatory phenomena</a></td><td align="right">94</td></tr>
+<tr><td align="left"><a href="#Tracings_of_auscultatory_phenomena">30. Tracings of auscultatory phenomena</a></td><td align="right">95</td></tr>
+<tr><td align="left"><a href="#Clinical_determination_of_diastolic_pressure_fast_drum">31. Clinical determination of diastolic pressure fast drum</a></td><td align="right">96</td></tr>
+<tr><td align="left"><a href="#Clinical_determination_of_diastolic_pressure_slow_drum">32. Clinical determination of diastolic pressure slow drum</a></td><td align="right">96</td></tr>
+<tr><td align="left"><a href="#Venous_blood_pressure_instrument">33. Venous blood pressure instrument</a></td><td align="right">121</td></tr>
+<tr><td align="left"><a href="#New_venous_pressure_instrument">34. New venous pressure instrument</a></td><td align="right">122</td></tr>
+<tr><td align="left"><a href="#Events_in_the_cardiac_cycle">35. Events in the cardiac cycle</a></td><td align="right">124</td></tr>
+<tr><td align="left"><a href="#Simultaneous_tracings_of_the_jugular_and_carotid_pulses">36. Simultaneous tracings of the jugular and carotid pulses</a></td><td align="right">125</td></tr>
+<tr><td align="left"><a href="#Jugular_and_carotid_tracings">37. Jugular and carotid tracings</a></td><td align="right">125</td></tr>
+<tr><td align="left"><a href="#Right_side_of_the_heart_showing_distribution_of_the_two_vagus_nerves">38. Right side of the heart showing distribution of the two vagus nerves</a></td><td align="right">127</td></tr>
+<tr><td align="left"><a href="#Normal_electrocardiogram">39. Normal electrocardiogram</a></td><td align="right">128</td></tr>
+<tr><td align="left"><a href="#Auricular_flutter">40. Auricular flutter</a></td><td align="right">132</td></tr>
+<tr><td align="left"><a href="#Auricular_fibrillation">41. Auricular fibrillation</a></td><td align="right">134</td></tr>
+<tr><td align="left"><span class="pagenum"><a name="Page_22" id="Page_22">[22]</a></span></td></tr>
+<tr><td align="left"><a href="#Auricular_fibrillations">42. Auricular fibrillation</a></td><td align="right">134</td></tr>
+<tr><td align="left"><a href="#Pulse_deficit">43. Pulse deficit</a></td><td align="right">135</td></tr>
+<tr><td align="left"><a href="#Ventricular_fibrillation">44. Ventricular fibrillation</a></td><td align="right">137</td></tr>
+<tr><td align="left"><a href="#Auricular_extrasystoles">45. Auricular extrasystoles</a></td><td align="right">139</td></tr>
+<tr><td align="left"><a href="#Ventricular_extrasystole">46. Ventricular extrasystole</a></td><td align="right">139</td></tr>
+<tr><td align="left"><a href="#Delayed_conduction">47. Delayed conduction</a></td><td align="right">141</td></tr>
+<tr><td align="left"><a href="#Partial_heart_block">48. Partial heart block</a></td><td align="right">141</td></tr>
+<tr><td align="left"><a href="#Complete_heart_block">49. Complete heart block</a></td><td align="right">142</td></tr>
+<tr><td align="left"><a href="#Alternating_periods_of_sinus_rhythm_and_auriculoventricular_rhythm">50. Alternating periods of sinus rhythm and auriculoventricular rhythm</a></td><td align="right">144</td></tr>
+<tr><td align="left"><a href="#Auriculoventricular_or_nodal_rhythm">51. Auriculoventricular or "nodal" rhythm</a></td><td align="right">144</td></tr>
+<tr><td align="left"><a href="#Influence_of_mechanical_pressure_on_the_right_vagus_nerve">52. Influence of mechanical pressure on the right vagus nerve</a></td><td align="right">144</td></tr>
+<tr><td align="left"><a href="#Schematic_distribution_of_right_and_left_vagus">53. Schematic distribution of right and left vagus</a></td><td align="right">145</td></tr>
+<tr><td align="left"><a href="#Blood_pressure_record_from_a_normal_reaction_to_ether">54. Blood pressure record from a normal reaction to ether</a></td><td align="right">149</td></tr>
+<tr><td align="left"><a href="#Chart_showing_the_method_of_recording_blood_pressure_during_an">55. Chart showing the method of recording blood pressure during an</a></td></tr>
+<tr><td align="left">operation</td><td align="right">150</td></tr>
+<tr><td align="left"><a href="#Method_of_using_blood_pressure_instrument_during_operation">56. Method of using blood pressure instrument during operation</a></td><td align="right">151</td></tr>
+<tr><td align="left"><a href="#Finger-tip_palpation_of_the_radial_artery">57. Finger-tip palpation of the radial artery</a></td><td align="right">178</td></tr>
+<tr><td align="left"><a href="#Finger-tip_palpations_of_the_radial_artery">58. Finger-tip palpation of the radial artery</a></td><td align="right">178</td></tr>
+<tr><td align="left"><a href="#Aneurysm_of_the_heart_wall">59. Aneurysm of the heart wall</a></td><td align="right">196</td></tr>
+<tr><td align="left"><a href="#Large_aneurysm_of_the_aorta_eroding_the_sternum">60. Large aneurysm of the aorta eroding the sternum</a></td><td align="right">198</td></tr>
+</table></div>
+
+<p><span class="pagenum"><a name="Page_24" id="Page_24"></a></span><span class="pagenum"><a name="Page_23" id="Page_23"></a></span></p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_25" id="Page_25">[25]</a></span></p>
+<h2>ARTERIOSCLEROSIS AND HYPERTENSION</h2>
+
+<hr style="width: 65%;" />
+<h2><a name="CHAPTER_I" id="CHAPTER_I"></a>CHAPTER I.</h2>
+
+
+<h3>ANATOMY</h3>
+
+
+<p>With the increased complexity of our modern life comes
+increased wear and tear on the human organism. "A man
+is as old as his arteries" is an old dictum, and, like many
+proverbs, the application to mankind today is, if anything,
+more pertinent than it was when the saying was
+first uttered. Notwithstanding the fact that the average
+age of mankind at death has been materially lengthened&mdash;the
+increase in years amounting to fourteen in the past
+one hundred years of history&mdash;clinicians and pathologists
+are agreed that the arterial degeneration known as arteriosclerosis
+is present to an alarming extent in persons over
+forty years of age. Figures in all vital statistics have shown
+us that all affections of the circulatory and renal systems
+are definitely on the increase. "Arterial diseases of various
+kinds, atheroma, aneurysm, etc., caused 15,685 deaths
+in 1915, or 23.3 per 100,000. This rate, although somewhat
+lower than the corresponding ones for 1912 and 1913, is
+higher than that for 1914, and is very much higher than
+that for 1900, which was 6.1."</p>
+
+<p>The great group of cases of which cardiac incompetence,
+aneurysm, cerebral apoplexy, chronic nephritis, emphysema,
+and chronic bronchitis are the most frequent and important
+appear as terminal events in which arteriosclerosis has
+probably played an important part.</p>
+
+<p>Thus, in the sense in which we speak of tuberculosis or
+pneumonia as a distinct disease, we can not so designate the
+diseased condition of the arteries.</p>
+
+<p>Arteriosclerosis is not a disease <b>sui generis</b>. It is best<span class="pagenum"><a name="Page_26" id="Page_26">[26]</a></span>
+viewed as a degeneration of the coats of the arteries, both
+large and small resulting in several different more or less
+distinct types.</p>
+
+<p>These types blend one into the other and in the same patient
+all types may be found. Thus the sclerosis of the
+arteries is the result of a variety of causes, none of which
+is definitely known in the sense of a bacterial disease. As
+we shall see later, one type of arteriosclerosis has a special
+pathology and etiology, the syphilitic arterial changes.</p>
+
+<p>Bearing in mind that arteriosclerosis (called by some
+"arteriocapillary fibrosis," by others "atherosclerosis")
+is not a true disease, it may, for convenience be defined as a
+chronic disease of the arteries and arterioles, characterized
+anatomically by increase or decrease of the thickness of the
+walls of the blood vessels, the initial lesion being a weakening
+of the middle layer caused by various toxic or mechanical
+agencies. This weakness of the media leads to
+secondary effects, which include hypertrophy or atrophy
+of the inner layer&mdash;and not infrequently hypertrophy of
+the outer layer&mdash;connective tissue formation and calcification
+in the vessels, and the formation of minute aneurysms
+along them. The term arteriocapillary fibrosis has
+a broader meaning, but is a cumbersome phrase, and conveys
+the idea that the capillary changes are an essential
+feature of the process, whereas these are for the most part
+secondary to the changes in the arteries. The veins do
+not always escape in the general morbid process, and when
+these are affected the whole condition is sometimes called
+vascular sclerosis or angiosclerosis.</p>
+
+<p>Upon the anatomical structure of the arteries depends,
+as a rule, the character and extent of the arteriosclerotic
+lesions. For the clear comprehension of the process, it is
+necessary to keep in mind the essential histological differences
+between the aorta and the larger and smaller
+branches of the arterial tree.</p>
+
+<p>The vascular system is often likened to a central pump,
+from which emanates a closed system of tubes, beginning<span class="pagenum"><a name="Page_27" id="Page_27">[27]</a></span>
+with one large distributing pipe, which gives rise to a series
+of tubes, whose number is constantly increasing at the
+same time that their caliber is decreasing in size. From
+the smallest of these tubes, larger and larger vessels collect
+the flowing blood, until, at the pump, two large trunks
+of approximately the same area as the one large distributing
+trunk empty the blood into the heart, thus completing
+the circle. This is but a rough illustration, and, while possibly
+useful, takes into account none of the vital forces
+which are constantly controlling every part of the distributing
+system.</p>
+
+
+<h4>General Structure of the Arteries</h4>
+
+<p>The aorta and its branches are highly elastic tubes, having
+a smooth, glistening inner surface. When the arteries
+are cut open, they present a yellowish appearance, due to
+the large quantity of elastic tissue contained in the walls.
+The elasticity is practically perfect, being both longitudinal
+and transverse. The essential portion of any blood vessel
+is the endothelial tube, composed of flat cells cemented together
+by intercellular substance and having no stomata
+between the cells. This tube is reinforced in different
+ways by connective tissue, smooth muscle fibers, and fibroelastic
+tissue. Although the gradations from the larger to
+the smaller arteries and from these to the capillaries and
+veins are almost insensible, yet particular arteries present
+structural characters sufficiently marked to admit of
+histological differentiation.</p>
+
+<p>The whole vascular system, including the heart, has an endothelial
+lining, which may constitute a distinct inner coat,
+the tunica intima, or may be without coverings, as in the
+case of the capillaries. The intima (Fig. 1) consists typically
+of endothelium, reinforced by a variable amount of fibroelastic
+tissue, in which the elastic fibers predominate. The
+tunica media is composed of intermingled bundles of elastic
+tissue, smooth muscle fibers, and some fibrous tissue.
+The adventitia or outer coat is exceedingly tough. It is<span class="pagenum"><a name="Page_28" id="Page_28">[28]</a></span>
+usually thinner than the media, and is composed of fibroelastic
+tissue. This division into three coats is, however,
+somewhat arbitrary, as in the larger arteries particularly
+it is difficult to discover any distinct separation into layers.</p>
+
+<div class="figcenter bord" style="width: 415px;"><a name="Cross_section_of_a_large_artery" id="Cross_section_of_a_large_artery"></a>
+<img src="images/fig_001.png" width="415" height="500" alt="Fig. 1.&mdash;Cross section of a large artery showing the division into the three coats; intima,
+media, adventitia. The intima is a thin line composed of endothelial cells. The
+wavy elastic lamina is well seen. The thick middle coat is composed of muscle fibers
+and fibroelastic tissue. The loose tissue on the outer (lower portion of cut) side of the
+media is the adventitia. (Microphotograph, highly magnified.)" title="Fig. 1.&mdash;Cross section of a large artery showing the division into the three coats; intima,
+media, adventitia... (Microphotograph, highly magnified.)" />
+<span class="caption">Fig. 1.&mdash;Cross section of a large artery showing the division into the three coats; intima,
+media, adventitia. The intima is a thin line composed of endothelial cells. The
+wavy elastic lamina is well seen. The thick middle coat is composed of muscle fibers
+and fibroelastic tissue. The loose tissue on the outer (lower portion of cut) side of the
+media is the adventitia. (Microphotograph, highly magnified.)</span>
+</div>
+
+<p>The muscular layer varies from single scattered cells, in
+the arterioles, to bands of fibers making up the body of the
+vessel in the medium-sized arteries and veins.</p>
+
+<p>There is elastic tissue in all but the smallest arteries,
+and it is also found in some veins. It varies in amount
+from a loose network to dense membranes. In the intima
+of the larger arteries the elastic tissue occurs as sheets,
+which under the microscope appear perforated and pitted,
+the so-called fenestrated membrane of Henle.</p>
+
+<p>The nutrient vessels of the arteries and veins, the vasa
+vasorum, are present in all the vessels except those less<span class="pagenum"><a name="Page_29" id="Page_29">[29]</a></span>
+than one millimeter in diameter. The vasa vasorum course
+in the external coat and send capillaries into the media,
+supplying the outer portion of the coat and the externa
+with nutritive material. The nutrition of the intima and
+inner portion of the media is obtained from the blood circulating
+through the vessel. Lymphatics and nerves are
+also present in the middle and outer layers of the vessels.</p>
+
+
+<h4>Arteries</h4>
+
+<p>The structure of the arteries varies notably, depending
+upon the size of the vessel. A cross section of the thoracic
+aorta reveals a dense network of elastic fibers, occupying
+practically all of the space between the single layer of
+endothelial cells and the loose elastic and connective tissue
+network of the outer layer. Smooth muscle fibers are
+seen in the middle coat, but, in comparison with the mass
+of elastic tissue, they appear to have only a limited function.</p>
+
+<p>In a cross section of the radial artery one sees a wavy
+outline of intima, caused by the endothelium following the
+corrugations of the elastica. The endothelium is seen as
+a delicate line, in which a few nuclei are visible. The
+media is comparatively thick, and is composed of muscle
+cells, arranged in flat bundles, and plates of elastic tissue.
+Between the media and the externa the elastic tissue is
+somewhat condensed to form the external elastic membrane.
+The adventitia varies much in thickness, being better
+developed in the medium-sized than in the large arteries.
+It is composed of fibrous tissue mixed with elastic
+fibers.</p>
+
+<p>"Followed toward the capillaries, the coats of the artery
+gradually diminish in thickness, the endothelium resting
+directly upon the internal elastic membrane so long as the
+latter persists, and afterward on the rapidly attenuating
+media. The elastica becomes progressively reduced until
+it entirely disappears from the middle coat, which then becomes
+a purely muscular tunic, and, before the capillary is
+reached, is reduced to a single layer of muscle cells. In<span class="pagenum"><a name="Page_30" id="Page_30">[30]</a></span>
+the precapillary arterioles the muscle no longer forms a
+continuous layer, but is represented by groups of fiber cells
+that partially wrap around the vessel, and at last are replaced
+by isolated elements. After the disappearance of
+the muscle cells the blood vessel has become a true capillary.
+The adventitia shares in the general reduction, and
+gradually diminishes in thickness until, in the smallest arteries,
+it consists of only a few fibroelastic strands outside
+the muscle cells." (Piersol's Anatomy.)</p>
+
+<p>The large arteries differ from those of medium size
+mainly in the fact that there is no sharp line of demarcation
+between the intima and the media. There is also much
+more elastic tissue distributed in firm bundles throughout
+the media, and there are fewer muscle fibers, giving a
+more compact appearance to the artery as seen in cross
+section. The predominance of elastic tissue permits of
+great distention by the blood forced into the artery at
+every heartbeat, the caliber of the tube being less markedly
+under the control of the vasomotor nerves than is the case
+in the small arteries, where the muscle tissue is relatively
+more developed. The adventitia of the large arteries is
+strong and firm, and is made up of interlacing fibroelastic
+tissue, of which some of the bundles are arranged longitudinally.</p>
+
+
+<h4>Veins</h4>
+
+<p>The walls of the veins are thinner than those of the arteries;
+they contain much less elastic and muscular tissue,
+and are, therefore, more flaccid and less contractile. Many
+veins, particularly those of the extremities, are provided
+with cup-like valves opening toward the heart. These
+valves, when closed, prevent the return of the blood to the
+periphery and distribute the static pressure of the blood
+column. The bulgings caused by the valves may be seen
+in the superficial veins of the arm and leg. There are no
+valves in the veins of the neck, where there is no necessity
+for such a protective mechanism, gravity sufficing to drain
+the venous blood from the cranial cavity.</p>
+
+<p><span class="pagenum"><a name="Page_31" id="Page_31">[31]</a></span></p>
+<h4>Capillaries</h4>
+
+<p>These are endothelial tubes in the substance of the organs,
+the tissue of the organ giving them the necessary
+support. They are the final subdivisions of the blood vessels,
+and the vast capillary area offers the greatest amount
+of resistance to the blood flow, thus serving to slow the
+blood stream and allowing time for nutritive substances
+or waste products to pass from and to the blood. Usually
+the capillaries are arranged in the form of a network,
+the channels in any one tissue being of nearly uniform size,
+and the closeness of the mesh depending upon the organ.</p>
+
+<p>As far back as 1865, Stricker observed contraction of the
+capillaries. This observation was apparently forgotten until
+revived again by Krogh recently. The latter finds that
+the capillaries are formed of cells which are arranged in
+strands encircling the vessel. The capillaries are rarely
+longer than 1 mm., and, according to Krogh, are capable of
+enormous dilatation.</p>
+
+<p>The rate of flow through any capillary area is very inconstant,
+and the usual explanation has been that the capillaries
+were endothelial tubes the blood flow of which was dependent
+upon the contraction or dilatation of the terminal
+arterioles. The actual fact that in an observed capillary
+area some capillaries are empty renders the above explanation
+untenable. The color of a tissue depends upon the state
+of filling of the capillaries with blood.</p>
+
+<p>It would seem that all the evidence now leads us to believe
+that the capillaries themselves are contractile and it
+is even possible that they may be under vasomotor control.
+If the anatomic structure as stated above, is correct, it
+would take but a slight contraction of the encircling cell to
+shut off completely the capillary. When the enormous capillary
+bed is considered, it is not inconceivable that circulating
+poisons may act on large areas and produce a true
+capillary resistance to the onflow of blood which might
+express itself, if long continued, in actual hypertrophy of
+the heart.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_32" id="Page_32">[32]</a></span></p>
+<h2><a name="CHAPTER_II" id="CHAPTER_II"></a>CHAPTER II.</h2>
+
+<h3>PATHOLOGY</h3>
+
+
+<p>The whole subject of the pathology of arteriosclerosis has
+been much enriched by the study of the experimental lesions
+produced by various drugs and microorganisms upon the
+aortas of rabbits. Simple atheroma must not be confused
+with the lesions of arteriosclerosis. The small whitish or
+yellowish plaques so frequently seen on the aorta and its
+main branches, may occur at any age, and have seemingly
+no great significance. Such plaques may grow to the size
+of a dime or larger, and even become eroded. They represent
+fatty degeneration of the intima which, at times, has
+no demonstrable cause; at times follows in the course of
+various diseases, and undoubtedly is due to disturbances of
+nutrition in the intima. Except for the remote danger of
+clot formation on the uneven or eroded spot, these places
+are of no special significance, and are not to be confused
+with the atheroma of nodular sclerosis.</p>
+
+<p>The lesions of arteriosclerosis are of a different character.
+It has been customary to differentiate three types:
+(1) nodular; (2) diffuse; (3) senile. It must be understood
+that this is not a classification of distinct types. As a rule
+in advanced arteriosclerosis, lesions representing all types
+and all grades are found. The nodular type, however, may
+occur in the aorta alone, the branches remaining free. This
+is most often found in syphilitic sclerosis where the lesion is
+confined to the ascending portion of the arch of the aorta.</p>
+
+<p>The retrogressive changes of advancing years can not
+be rightly termed disease, yet it becomes necessary to regard
+them as such, for the senile changes, as we shall see,
+may be but the advanced stages of true arteriosclerosis.
+Much depends on the nature of the arterial tissue and much<span class="pagenum"><a name="Page_33" id="Page_33">[33]</a></span>
+on the factors at work tending to injure the tissue. A man
+of forty years may therefore have the calcified, pipe stem
+arteries of a man of eighty. Our parents determine, to
+great extent, the kind of tissue with which we start life.
+The arteries are elastic tubes capable of much stretching
+and abuse. In the aorta and large branches there is much
+elastic tissue and relatively little muscle. When the vessels
+have reached the organs, they are found to be structurally
+changed in that there is in them a relatively small amount
+of elastic tissue but a great deal of smooth muscle. This
+is a provision of nature to increase or decrease the supply
+of blood at any point or points.</p>
+
+<p>The aorta and the large branches are distributing tubes
+only. It is after all in the arterioles and smaller arteries
+that the lesions of arteriosclerosis do the most damage. A
+point to be emphasized is that the whole arterial system is
+rarely, if ever, attacked uniformly. That is, there may be
+a marked degree of sclerosis in the aorta and coronary
+arteries with very little, if any, change in the radials. On
+the contrary, a few peripheral arteries only may be the seat
+of disease. A case in point was seen at autopsy in which
+the aorta in its entirety and all the large peripheral
+branches were absolutely smooth. In the brain, however,
+the arteries were tortuous, hard, and were studded with
+miliary aneurysms. It is not possible to judge accurately
+the state of the whole arterial system by the stage of the
+lesion in any one artery; but on the whole one may say that
+an undue thickening of the radial artery indicates analogous
+changes in the mesenteric arteries and in the aorta.</p>
+
+<p>So far as the anatomical lesions in the aorta and
+branches are concerned, there is much uniformity even
+though the etiologic factors have been diverse. The only
+difference is one of extent. To Thoma we owe the first
+careful work on arteriosclerosis. He regarded the lesion
+in arteriosclerosis as one situated primarily in the media;
+there is a lack of resistance in this coat. His views are<span class="pagenum"><a name="Page_34" id="Page_34">[34]</a></span>
+now chiefly of historical interest. As the author understands
+him, he considered a rupture in the media to be the
+cause of a local widening and consequently the blood could
+not be distributed evenly to the organ which was supplied
+by the diseased artery or arteries. Moreover, there was
+danger of a rupture at the weak spot unless this were
+strengthened. It was essential for the even distribution of
+blood that the lumen be restored to its former size. Nature's
+method of repair was a hypertrophy of the subintimal
+connective tissue and the formation of a nodule at
+that point. The thickening was compensatory, resulting
+in the establishment of the normal caliber of the vessel.
+Thoma showed that by injecting an aorta in the subject of
+such changes, with paraffin at a pressure of 160 mm. of mercury,
+these projections disappeared and the muscle bulged
+externally. He recognized the fact that the character of
+the artery changed as the years passed, and to this form
+he gave the name, primary arteriosclerosis. To the group
+of cases caused by various poisonous agents, or following
+high peripheral resistance and consequent high pressure,
+he gave the name, secondary arteriosclerosis. This is a
+useful but not essential division, as the changes which age
+and high tension produce may not be different from those
+produced in much younger persons by some circulating
+poison. And most important to bear in mind, octogenarians
+may have soft, elastic arteries.</p>
+
+<p>As the body ages, certain changes usually take place in
+the arteries leading to thickening and inelasticity of their
+walls. This is a normal change, and in estimating the palpable
+thickening of an artery, such as the radial, the age
+of the individual must always be considered.</p>
+
+<p>Thayer and Fabyan, in an examination of the radial
+artery from birth to old age, found that, in general, the
+artery strengthens itself, as more strain is thrown upon it,
+by new elastica in the intima and connective tissue in the
+media and adventitia. Up to the third decade there is only<span class="pagenum"><a name="Page_35" id="Page_35">[35]</a></span>
+a strengthening of the media and adventitia. During the
+third and fourth decades there is also distinct connective
+tissue thickening in the intima. "In other words, the strain
+has begun to tell upon the vessel wall, and the yielding tube
+fortifies itself by the connective tissue thickening of the
+intima and to a lesser extent of the media." By the fifth
+decade the connective tissue deposits in the intima are
+marked, there is an increase of fibrous tissue upon the
+medial side of the intima and, in lesser degree, throughout
+the media. "Finally, in these sclerotic vessels degenerative
+changes set in, which are somewhat different from those
+seen in the larger arteries, consisting, as they do, of local
+areas of coagulation necrosis with calcification, especially
+marked in the deep layers of the connective tissue thickenings
+of the intima, and in the muscle fibers of the media,
+particularly opposite these points. These changes may ... go
+on to actual bone formation." The mesenteric
+artery differs in some respects from the radial, but in the
+main, the changes brought about by age are the same.
+Thayer and Fabyan note two striking points of difference:
+"(1) calcification is apparently much less frequent than in
+the radials; (2) in several cases plaques were seen with
+fatty softening of the deeper layers of the intima and superficial
+proliferation&mdash;a picture which we have never seen in
+the radial." (See Fig. 2.)</p>
+
+<div class="figcenter bord" style="width: 434px;">
+<a name="Cross_section_of_a_coronary_artery" id="Cross_section_of_a_coronary_artery"></a>
+
+<img src="images/fig_002.png" width="434" height="500" alt="Fig. 2.&mdash;Cross section of a coronary artery, &#215;50, showing nodular sclerosis. Note the
+heaping up of cells in the intima, the fracture of the elastica, and the destruction of the
+media beneath the nodule. The primary lesion evidently was in the media. The thickened
+intima is the effort on the part of nature to heal the breach. At such places as
+shown here aneurysms may form. (Microphotograph.)" title="Fig. 2.&mdash;Cross section of a coronary artery, &#215;50, showing nodular sclerosis. Note the
+heaping up of cells in the intima, the fracture of the elastica, and the destruction of the
+media beneath the nodule.... (Microphotograph.)" />
+<span class="caption">Fig. 2.&mdash;Cross section of a coronary artery, &#215;50, showing nodular sclerosis. Note the
+heaping up of cells in the intima, the fracture of the elastica, and the destruction of the
+media beneath the nodule. The primary lesion evidently was in the media. The thickened
+intima is the effort on the part of nature to heal the breach. At such places as
+shown here aneurysms may form. (Microphotograph.)</span>
+</div>
+
+<p>Aschoff's studies of the aorta show that, "in infancy the
+elastic laminæ of the media stand out sharply defined, well
+separated from each other by the muscle layers, which are
+well developed.... From childhood there is to be observed
+a slowly progressive increase in the elastic elements of the
+media. Not only do the individual lamellæ seen in cross-sections
+become thicker, but also they afford an increasing
+number of fine secondary filaments feathering off from these
+and crossing the muscle layer, so that now they are no
+longer sharply defined, but more ragged upon cross-section.
+This progressive increase attains its maximum at or about<span class="pagenum"><a name="Page_36" id="Page_36">[36]</a></span>
+the age of thirty-five, and from now on for the next fifteen
+years the condition is relatively stationary. After fifty
+there is to be observed a slowly progressive atrophy of
+the elastica. The media becomes obviously thinner and
+presumably weaker." (Adami.) It has also been found
+(Klotz) that after the age of thirty-five, the muscle of the
+media begins to exhibit fatty degeneration which after fifty
+years is well marked. The fatty degeneration may then
+give place to a calcareous infiltration or the fibers may undergo
+complete absorption. It would appear that the thinning
+of the aortic media is due not so much to the atrophy
+of the elastic tissue as to that of the muscle tissue. The
+elastic tissue does lose its specific property and the artery
+thus becomes practically a connective tissue tube.</p>
+
+<p><span class="pagenum"><a name="Page_37" id="Page_37">[37]</a></span>Scheel has made very careful measurements of the
+ascending, the thoracic, and the abdominal aorta, and the
+pulmonary artery. He found that from birth to sixty
+years, the aorta became progressively wider and lost its
+elasticity. The pulmonary changed little, if at all, after
+thirty to forty years, and where before it was wider than
+the aorta, it now was found to be smaller. In chronic
+nephritis both were widened. The continuous increase of
+width and length of the aorta stands in reverse relationship
+to the elasticity of its walls.</p>
+
+<p>Although the division of the lesions into nodular, diffuse,
+and senile has been the usual one, it is better to separate
+three groups into (1) nodular, (2) diffuse or senile, and (3)
+syphilitic. There is more known about the histology of
+the syphilitic form and the lesions which consist of puckerings
+and scars seen on opening an aorta just above the
+valves, and on the ascending portion of the arch are characteristic.
+A macroscopic examination suffices in most cases
+for a definite diagnosis.</p>
+
+<p>In the nodular form the lesions are found on the aorta
+and large branches particularly at or near the orifices of
+branching vessels. These nodules may increase in size,
+forming rather large, slightly raised plaques of yellowish-white
+color. They are, as a rule, irregularly scattered
+throughout the aorta and branches and tend to be more
+numerous and larger in the abdominal aorta. The initial
+lesion is in the media, consisting of an actual dissolution of
+this coat with rupture of the elastic fibers and infiltration
+with small round cells. There is thus a weak spot in the
+artery. Hypertrophy of the intimal cells takes place,
+layer upon layer being added in an attempt to strengthen
+the vessel at the injured place. Coincidently with this,
+there is thickening by a connective tissue growth in the
+adventitia. The process begins, at least in syphilis, around
+the terminals of the vasa vasorum. It will be recalled that
+the blood supply of the inner portion of the media comes<span class="pagenum"><a name="Page_38" id="Page_38">[38]</a></span>
+from within the vessel itself. As the intimal growth increases,
+the blood supply is cut off. The inevitable result
+is softening of the portion farthest from the lumen of the
+vessel. As a rule there has been a sufficient growth of connective
+tissue in the media and adventitia to repair the
+damage done to the media. This softening and dissolution
+gives rise to a granular debris composed of degenerated
+cells and fat. This is the so-called atheromatous abscess.
+There are no leucocytes as in ordinary pus. These "abscesses"
+are frequent and in rupturing leave open ulcers
+with smooth bases, the atheromatous ulcer. A further
+change which often takes place is calcification of the bases
+of the ulcers and calcification of the softened spots before
+rupture takes place. This only occurs in advanced cases.
+(See Fig. 3.)</p>
+
+
+<div class="figcenter bord" style="width: 201px;"><a name="Arteriosclerosis_of_the_thoracic_and_abdominal_aorta" id="Arteriosclerosis_of_the_thoracic_and_abdominal_aorta"></a>
+<img src="images/fig_003.png" width="201" height="500" alt="Fig. 3.&mdash;Arteriosclerosis of the thoracic and abdominal aorta, showing irregular
+nodules, atheromatous plaques, denudation of the intima, thin plates of bone scattered
+throughout with spicules extending into the lumen of the vessel. Note the contraction
+of the openings of the large branches, the rough appearance of the aorta and the greater
+degree of sclerosis of the upper two-thirds, i. e., of the aorta above the diaphragm.
+This aorta in the recent state was much thickened and almost inelastic." title="Fig. 3.&mdash;Arteriosclerosis of the thoracic and abdominal aorta, showing irregular
+nodules, atheromatous plaques, denudation of the intima, thin plates of bone scattered
+throughout with spicules extending into the lumen of the vessel...." />
+<span class="caption">Fig. 3.&mdash;Arteriosclerosis of the thoracic and abdominal aorta, showing irregular
+nodules, atheromatous plaques, denudation of the intima, thin plates of bone scattered
+throughout with spicules extending into the lumen of the vessel. Note the contraction
+of the openings of the large branches, the rough appearance of the aorta and the greater
+degree of sclerosis of the upper two-thirds, i. e., of the aorta above the diaphragm.
+This aorta in the recent state was much thickened and almost inelastic.</span>
+</div>
+
+<div class="figcenter" style="width: 359px;">
+<a name="Arteriosclerosis_of_the_arch_of_the_aorta" id="Arteriosclerosis_of_the_arch_of_the_aorta"></a>
+<img src="images/fig_004.png" width="359" height="500" alt="Fig. 4.&mdash;Arteriosclerosis of the arch of the aorta. Numerous calcified plaques,
+thickening and curling of the aortic valves, giving rise to insufficiency of the aortic
+valves. The aortic ring is rigid and not much dilated. (Milwaukee County Hospital.)" title="Fig. 4.&mdash;Arteriosclerosis of the arch of the aorta.... (Milwaukee County Hospital.)" />
+<span class="caption">Fig. 4.&mdash;Arteriosclerosis of the arch of the aorta. Numerous calcified plaques,
+thickening and curling of the aortic valves, giving rise to insufficiency of the aortic
+valves. The aortic ring is rigid and not much dilated. (Milwaukee County Hospital.)</span>
+</div>
+
+<div class="figcenter bord" style="width: 200px;">
+<a name="Normal_Aorta" id="Normal_Aorta"></a>
+
+<img src="images/fig_005.png" width="200" height="500" alt="Fig. 5.&mdash;Normal aorta. Compare with Fig. 3. Note the perfectly smooth, glossy appearance
+of the intima. The openings of all the intercostal arteries are distinctly seen.
+In the recent state this artery was highly elastic, capable of much stretching both
+transversely and longitudinally." title="Fig. 5.&mdash;Normal aorta. Compare with Fig. 3. Note the perfectly smooth, glossy appearance
+of the intima. The openings of all the intercostal arteries are distinctly seen...." />
+<span class="caption">Fig. 5.&mdash;Normal aorta. Compare with Fig. 3. Note the perfectly smooth, glossy appearance
+of the intima. The openings of all the intercostal arteries are distinctly seen.
+In the recent state this artery was highly elastic, capable of much stretching both
+transversely and longitudinally.</span>
+</div>
+
+<p>Rather contrary to what one would expect, there are no
+new capillaries advancing from the media to the intima in
+the nodular form of arteriosclerosis, consequently there is
+no granulation tissue to heal and leave scars. It must be
+borne in mind that these changes rarely, if ever, are the
+only ones found throughout the arterial system. Nevertheless,
+the manifold changes, as will be shown within, appear
+to be but stages of one primary process.</p>
+
+<p>The character of the changes which are known as diffuse
+arteriosclerosis seems to have, at first sight, little in common
+with those of the nodular sclerosis. The aorta may
+or may not have plaques of nodular sclerosis, while the
+arteries, such as the radial or temporal, may be beaded or
+pipe stem in hardness. In spite of these far advanced
+peripheral lesions the aorta may appear smooth but it is
+markedly dilated, particularly the thoracic portion, it is
+noticeably thinned even on macroscopic examination, it
+has elongated as evidenced by its slight tortuosity, and it
+has lost the greater part of its elasticity. The abdominal
+aorta is not so extensively affected, although this, too, shows
+some elongation and slight thinning. This is considered by<span class="pagenum"><a name="Page_39" id="Page_39">[39]</a></span>
+some pathologists to be the uncomplicated form of the so-called
+senile arteriosclerosis. It is more of the nature of a
+degenerative change, it is true, but, as will be shown later,
+it has its beginnings, at times, in comparatively young persons<span class="pagenum"><a name="Page_40" id="Page_40">[40]</a></span>
+and its etiology is not simple. This type has been
+studied most carefully by Moenckeberg, who showed that on
+the large branches of the aorta there were depressions due
+to a degeneration of the middle coat. These depressions
+encircled the vessel to a greater or lesser extent, causing<span class="pagenum"><a name="Page_41" id="Page_41">[41]</a></span>
+small bulgings at such places and giving to the vessel a
+beaded appearance. On viewing such an artery held to the
+light, the sacculated spots are seen to be much thinner than
+the contiguous normal artery. Associated with such
+changes in the aorta and large branches is marked sclerosis
+of the smaller arteries. Intimal fibrosis is common, together
+with hypertrophy and fibrosis of the middle coat. Not infrequently
+periarterial thickening is also seen. Calcification<span class="pagenum"><a name="Page_43" id="Page_43">[43]</a></span><span class="pagenum"><a name="Page_42" id="Page_42"></a></span>
+of the media is found and is said to be preceded by hypertrophy
+of the middle coat.</p>
+
+<p>Pure cases of this, the so-called Moenckeberg type, are
+seen but seldom. Most commonly there are nodules and
+plaques in the aorta and large branches together with thinning
+and sacculation of other portions of the vessels' walls.
+While the two processes appear at a glance to be so different
+from each other, it is possible for them to have a
+common origin. The initial lesion is in the media but the
+resulting sclerotic changes depend upon the kind of vessel,
+the strength of the coats, the pressure in the vessel, and
+other causes.</p>
+
+<p>Thus the sclerosis of the radials of such an extent that
+these arteries are easily palpable, appears to be a different
+process from that of the sclerosis in the aorta, yet fundamentally
+it is the same. The difference lies in the anatomic
+structure of the two vessels, and possibly also in the
+degree of stretching and strain to which the vessels are
+subjected at every heart beat. In the radial artery the
+media as usual is affected first. The muscle cells undergo
+degeneration and either marked thickening takes place or
+sacculation results, depending upon the severity of the exciting
+cause. Calcification of the media is common. This
+occasionally takes the form of rings encircling the vessel,
+and gives to the examining finger the sensation of feeling
+a string of fine beads. There may be calcification of the
+subintimal tissue without deposits of lime salts in the media,
+but this is more commonly found in the larger arteries.
+When the calcification occurs in plates through the media,
+the well known pipe stem vessel is produced. (Fig. 6.)</p>
+
+<div class="figcenter bord" style="width: 290px;">
+<a name="Radiogram_showing_calcification_of_both_radial_and_ulnar_arteries" id="Radiogram_showing_calcification_of_both_radial_and_ulnar_arteries"></a>
+<img src="images/fig_006.png" width="290" height="500" alt="Fig. 6.&mdash;Radiogram of a man aged seventy-five, showing calcification of both radial and
+ulnar arteries." title="Fig. 6.&mdash;Radiogram of a man aged seventy-five, showing calcification of both radial and
+ulnar arteries." />
+<span class="caption">Fig. 6.&mdash;Radiogram of a man aged seventy-five, showing calcification of both radial and
+ulnar arteries.</span>
+</div>
+
+<p>The senile sclerosis found in old people is usually a combination
+of the Moenckeberg type in the large and medium-sized
+arteries, and the nodular type in the aorta, leading
+eventually to calcareous intimal deposits, and widened,
+elongated, inelastic aorta.</p>
+<p><span class="pagenum"><a name="Page_44" id="Page_44">[44]</a></span></p>
+
+<h4>Syphilitic Aortitis</h4>
+
+<div class="figcenter" style="width: 375px;">
+
+<a name="Syphilitic_aortitis_of_long_standing" id="Syphilitic_aortitis_of_long_standing"></a>
+
+<img src="images/fig_007.png" width="375" height="500" alt="Fig. 7.&mdash;Syphilitic aortitis of long standing. The aortic valves are curled and
+thickened, the heart is enlarged and the cavity of the left ventricle is dilated. (Milwaukee
+County Hospital.)" title="Fig. 7.&mdash;Syphilitic aortitis of long standing. The aortic valves are curled and
+thickened, the heart is enlarged and the cavity of the left ventricle is dilated. (Milwaukee
+County Hospital.)" />
+<span class="caption">Fig. 7.&mdash;Syphilitic aortitis of long standing. The aortic valves are curled and
+thickened, the heart is enlarged and the cavity of the left ventricle is dilated. (Milwaukee
+County Hospital.)</span>
+</div>
+
+<p>The seat of election of the syphilitic poison is in the aorta
+just above the aortic valves, Fig. 7, and in the ascending
+portion of the arch. There are semitranslucent, hyaline-like
+plaques which have a tendency to form into groups and,<span class="pagenum"><a name="Page_45" id="Page_45">[45]</a></span>
+instead of undergoing an atheromatous change as in the ordinary
+nodular form of arteriosclerosis, they are prone to
+scar formation with puckering, so that macroscopically the
+nature of the process may, as a rule, be readily diagnosed.
+Microscopically the process is found to be a subacute inflammation
+of the media, which has been called a mesaortitis.
+There is marked small celled infiltration around some
+of the branches of the vasa vasorum and there appears to be
+actual absorption of the tissue elements of the middle coat.
+This is accompanied by hypertrophy of the intimal tissue.
+There follows degeneration in the deeper portions of this
+new tissue and new capillaries are formed which have their
+origin in the inflammatory area in the media. As is everywhere
+the case throughout the body, granulation tissue in
+the process of healing contracts and forms scars. This explains
+the scar formation in the aorta. When the process
+is more acute, instead of there being a reparative attempt
+on the part of the intima, there is actual stretching of the
+wall at the weakened spot and there results an aneurysmal
+dilatation. <b>Spirochetæ pallidæ</b> have been found in the degenerated
+media and in small gummata which were situated
+beneath the intima. Within the past years it has been
+found that a large percentage of patients with cardiovascular
+disease give the Wassermann reaction. In cases of
+aortic insufficiency, the reaction is present in almost every
+case. This is in marked contrast to the cases of diffuse endocarditis
+where the reaction is rarely present.</p>
+
+<p>According to Adami the effects of syphilis upon the aorta
+are the following: (1) the primary disturbance is a granulomatous,
+inflammatory degeneration of the media; (2) this
+leads to a local giving way of the aorta; (3) if this be
+moderate it results in a strain hypertrophy of the intima
+and of the adventitia, with the development of a nodose intimal
+sclerosis; (4) if it be extreme, there results, on the
+contrary, an overstrain atrophy of the intima and aneurysm
+formation; (5) the intimal nodosities are here not of an<span class="pagenum"><a name="Page_46" id="Page_46">[46]</a></span>
+inflammatory type and are nonvascular, although, with the
+progressive laying down of layer upon layer of connective
+tissue on the more intimal aspect of the intima, the earlier
+and deeper-placed layers of new tissue gain less and less
+nourishment, and so are liable to exhibit fatty degeneration
+and necrosis; (6) these products of necrosis exert a chemotactic
+influence upon the nearby vessels of the medial granulation
+tissue, with, as a result, (a) a secondary and late
+entrance of new vessels into the early and deeply-placed
+atheromatous area, (b) absorption of the necrotic products,
+(c) replacement by granulation tissue, (d) contraction of
+the granulation tissue, and (e) depression and scarring of
+the sclerotic nodules so characteristic of syphilitic sclerosis.</p>
+
+<p>In the smaller arteries and arterioles the arteriosclerotic
+process appears on superficial examination to be a different
+process from that in the aorta and large arteries, but the
+difference is only apparent. It will be recalled that there
+is relatively much more muscle tissue in the arterioles than
+in the large arteries. The size, of course, is much less.
+Large nodular plaques are not possible. The atheromatous
+degeneration is not marked. In the smaller muscular
+arteries is seen the intimal proliferation, the stretching of
+the Moenckeberg type, and the calcification of the media
+rather than the intima. The media is thinned beneath the
+marked intimal proliferation so that the artery exhibits
+translucent areas when held to the light. Again, there is
+seen degeneration of the muscle and replacement by connective
+tissue with or without hypertrophy of the intima.
+In the arterioles three kinds of changes occur: a muscular
+hypertrophy; a fibrosis of all the coats; or a marked proliferation
+of the intimal endothelium. The last two are
+probably the same process, the connective tissue having its
+origin in the proliferated endothelial cells. Such a deposition
+of layer upon layer of cells in an arteriole and the resulting
+fibrosis leads to the condition of disappearance of
+the lumen of the vessel, endarteritis obliterans. This obliterating<span class="pagenum"><a name="Page_47" id="Page_47">[47]</a></span>
+endarteritis is not, of course, due alone to
+syphilis. Syphilis is only a type of poison which produces
+such changes as have been described above. It is in the
+organs such as the kidney, liver, spleen, and intestines that
+one sees the most perfect examples of this obliterating
+endarteritis. Endarteritis deformans is a term applied to
+the condition of the arteries as a result of irregular thickenings
+and deposits of lime salts in the walls. These
+changes give rise to marked tortuosity of the vessels.</p>
+
+<p>Occasionally such an obliterating process takes place in
+a larger artery. A thrombus forms and by a process of
+central softening, new channels permeate the thrombus,
+thus restoring to some extent the function of the vessel.</p>
+
+<p>That the same process leads at one time to thinning and
+at another time to thickening of the arterial walls has been
+noted above. Prof. Adami holds that the regular development
+of layer upon layer of new connective tissue is non-inflammatory.
+He calls it a "strain hypertrophy." It is
+analogous to the localized hypertrophy of bone where the
+muscle tendons are attached, as is so frequently seen in
+athletes. The increased tension on connective tissue, provided
+that it is not overstrained, leads to its overgrowth,
+but only when there is sufficient nourishment. Such conditions
+are adequately fulfilled in the arteries. When a
+local giving way under pressure occurs in the media, the
+intima is put on the stretch (see Fig. 8), and there results
+a hypertrophy of the intima until the volume of the new
+tissue and the resistance which this affords to the mean distending
+force, balances the loss sustained by the weakened
+media. When the balance is struck, the hypertrophy is
+arrested. The youngest tissue is thus found directly beneath
+the endothelium. Now should this local weakening of
+the media have an acute origin, instead of a stimulus to
+growth there is overstrain, and there is, in consequence, not
+hypertrophy but atrophy. The beginning process is here
+a mesaortitis, but the acuteness of the poison, and the pressure<span class="pagenum"><a name="Page_48" id="Page_48">[48]</a></span>
+from within the artery so stretches the artery that
+there is no compensatory hypertrophy, but a thinning, and
+the ground is prepared for aneurysmal dilatation or pouching.</p>
+
+<div class="figcenter" style="width: 308px;">
+<a name="Diagrammatic_representation_of_strain_hypertrophy" id="Diagrammatic_representation_of_strain_hypertrophy"></a>
+
+<img src="images/fig_008.png" width="308" height="500" alt="Fig. 8.&mdash;I, media weakened at M&#39; with overgrowth of intima filling in the depression.
+II, with postmortem rigor and contraction of the muscles of the media and removal
+of the blood pressure from within, the stretched media at M&#39;&#39; contracts; the intimal
+thickening thus projects into the arterial lumen. (After Adami.)" title="Fig. 8.&mdash;I, media weakened at M&#39; with overgrowth of intima filling in the depression.
+II, with postmortem rigor and contraction of the muscles of the media and removal
+of the blood pressure from within, the stretched media at M&#39;&#39; contracts; the intimal
+thickening thus projects into the arterial lumen. (After Adami.)" />
+<span class="caption">Fig. 8.&mdash;I, media weakened at M&#39; with overgrowth of intima filling in the depression.
+II, with postmortem rigor and contraction of the muscles of the media and removal
+of the blood pressure from within, the stretched media at M&#39;&#39; contracts; the intimal
+thickening thus projects into the arterial lumen. (After Adami.)</span>
+</div>
+
+<p>Again, one not infrequently encounters intimal nodosities
+when the underlying media appears of normal thickness.
+The explanation of this apparent exception is that the media
+in the living aorta is actually thinned, but the layers of
+subintimal tissue deposited over the weak spot due to strain
+hypertrophy become bulged inward when the pressure is
+relieved, as at postmortem. The media has not lost all of
+its elasticity (see Fig. 9), hence it contracts and there is
+the appearance of a nodule on the intima beneath which is a
+media equal in thickness to that of the healthy surrounding
+media.</p>
+
+<div class="figcenter" style="width: 171px;">
+
+<a name="Strain_hypertrophy" id="Strain_hypertrophy"></a>
+
+<img src="images/fig_009.png" width="171" height="500" alt="Fig. 9.&mdash;Schematic representation of the increased strain brought to bear upon the
+cells of the intima, Int., when the media, Med., undergoes a localized expansion through
+relative weakness. (After Adami.)" title="Fig. 9.&mdash;Schematic representation of the increased strain brought to bear upon the
+cells of the intima, Int., when the media, Med., undergoes a localized expansion through
+relative weakness. (After Adami.)" />
+<span class="caption">Fig. 9.&mdash;Schematic representation of the increased strain brought to bear upon the
+cells of the intima, Int., when the media, Med., undergoes a localized expansion through
+relative weakness. (After Adami.)</span>
+</div>
+
+<p>The essential lesion in arteriosclerosis of the aorta and
+large arteries is a degeneration in the middle coat. This
+may be brought about by a variety of poisons circulating in
+the body. In syphilis, for example, the initial lesion has<span class="pagenum"><a name="Page_49" id="Page_49">[49]</a></span>
+been shown to be a mesaortitis. The media seems to be dissolved,
+the artery is consequently thinned, there is actual
+depression along the level of the vessel. The elastic fibers
+disappear and small-celled infiltration takes its place. The
+intima hypertrophies, layer upon layer being added in an
+attempt to restore the strength of the vessel. There is also,
+as a rule, rather pronounced hypertrophy of the adventitia.</p>
+<p><span class="pagenum"><a name="Page_50" id="Page_50">[50]</a></span></p>
+
+<h4>Experimental Arteriosclerosis</h4>
+
+<p>Within the past few years many workers have attempted
+by various means, to produce arterial lesions in animals,
+chiefly rabbits and dogs. The present status is somewhat
+chaotic, some affirming and some denying that arterial
+changes follow the various methods employed. Following
+the injection of small, repeated doses of adrenalin over a
+certain period of time, changes occur in the arteries of
+rabbits which are arteriosclerotic in type, the essential
+lesion being a degeneration of the muscular and elastic tissue
+of the media with the consequent production of aneurysm
+in the vessel. This is said by some to be quite like
+the type of arteriosclerosis in man which has been so well
+described by Moenckeberg. The degenerations in the arteries
+following the experimental lesions are of the nature
+of a fatty metamorphosis, and later proceed to calcification.
+Barium chloride, digitalin, physostigmin, nicotin and other
+substances, as well as adrenalin, have been found to exert
+a selective toxic action on the muscle cells of the middle
+coat of the aorta. The infundibular portion of the pituitary
+body, the portion which is developed from the infundibulum
+of the brain, possesses an internal secretion, which, injected
+intravenously, causes a marked rise of blood pressure and
+slowing of the heart beat. So far as I know, this active
+principle of the gland has not been used in an attempt to
+produce experimentally the lesions of arteriosclerosis.</p>
+
+<p>Wacker and Hueck succeeded in producing aortic disease
+in rabbits which they considered to be in many points
+quite like human arteriosclerosis. They injected the rabbits
+intravenously with cholesterin. They feel that this is
+of great importance in view of the fact that exercise (muscle
+metabolism) dyspnea, certain poisons, as well as adrenalin,
+and even adrenal extirpation occasion a high cholesterin
+content of the blood. Anitschow's experiments are
+confirmatory. He fed rabbits on large amounts of cholesterin-containing substances<span class="pagenum"><a name="Page_51" id="Page_51">[51]</a></span>
+(yolk of egg, brain tissue) and
+pure cholesterin and found changes in the intima and inner
+portion of the media consisting of fatty infiltration between
+the muscle and elastic fibres, advent of small round cells
+and large phagocytic cells containing fat droplets of cholesterin
+esters. The elastic fibres were dissolved, broken up
+into fibrillæ and these seemed to be absorbed. The internal
+elastic lamina as such disappeared and the inner layer of
+the aorta fused with the middle coat. He considers these
+changes to be quite analogous to those found in human
+aortas.</p>
+
+<p>Oswald Loeb produced changes in the arteries of rabbits
+by feeding them sodium lactate (lactic acid). His controls
+fed on other acids became cachectic, but showed no arterial
+changes. He further found that in 100 gm. of human blood
+there was normally from 15 to 30 mg. of lactic acid. After
+heavy work, he found as much as 150 gm. He considers
+that after adrenalin or nicotin injections, the function of the
+liver is so disturbed that lactic acid is not bound. The arteriosclerosis
+is actually due to the presence of free lactic
+acid in the circulation. He succeeded, also, in producing
+lesions of the intima in a dog fed for a long time on protein
+poor diet, plus lactic acid and sodium lactate.</p>
+
+<p>Another investigator, Steinbiss, fed rabbits on animal
+proteins only, a diet totally foreign to their natural habits.
+He succeeded, however, in keeping some alive for three
+months. He also tried various substances and in the general
+conclusions says that no aortic changes could be produced
+in animals kept in natural living conditions by any mechanical
+means, increase of blood pressure, digital compression,
+hanging by hind legs, etc. In infectious diseases, especially
+septic, widespread sclerotic changes occurred in the aorta.
+A most suggestive conclusion in this "the most important
+result of feeding rabbits with animal proteins is, along with
+a constant glycosuria, disease of the aorta and peripheral
+arteries which is identical with changes in the aorta produced<span class="pagenum"><a name="Page_52" id="Page_52">[52]</a></span>
+by injections of adrenalin. The degree of disease of
+the circulatory system increases with the duration of the
+experiment."</p>
+
+<p>By a small addition of vegetable to the protein diet, the
+lives of the animals were prolonged at will. With this
+modification of the experiment, the findings in the vessel
+walls were noticeably altered. The changes affected chiefly
+the intima, to less degree the media, and histologically were
+very much like human intimal disease.</p>
+
+<p>I have been unable to produce the slightest arterial lesions
+in rabbits by intravenous injections of lead. Frothingham
+had no success feeding animals with lead. In a
+study of autopsy material from persons up to 40 years, who
+died of infectious disease, he found changes in the arteries
+of those who had succumbed to infection with the pus cocci
+or to very severe infectious disease. These changes were,
+however, localized, and were not like those of the general
+diffuse arteriosclerosis.</p>
+
+<p>Adler has recently reported experiments on dogs, to
+which he fed or injected intravenously various substances
+supposed to induce arteriosclerotic changes. He was unable
+to find any arterial lesions comparable to human arteriosclerosis.</p>
+
+<p>The difficulty experienced by experimenters is not surprising
+when the character of the changes is considered.
+Arteriosclerosis is not an acute process. In its very nature,
+it is of months' or years' standing, the specific changes are
+of slow growth, and more in the nature of degeneration. It
+would seem that a very careful study of the histories of
+those with arteriosclerosis and a final examination upon the
+actual tissue might eventually give us data for the etiology.</p>
+
+<p>The most frequent site of disease in these experimental
+lesions is the thoracic aorta, and it is there also that the
+most severe changes are seen. While the toxic action is felt
+in the vessels all over the body, the lesions are, as a rule,
+scattered and small. The thoracic aorta stands the brunt<span class="pagenum"><a name="Page_53" id="Page_53">[53]</a></span>
+of the high pressure, and this combined with the poisonous
+action of the drug or drugs, results in the formation of a
+fusiform aneurysmal dilatation which stops at the diaphragmatic
+opening. The aortic opening in the diaphragm
+seems to act as a flood gate, allowing only a certain amount
+of blood to flow through, and thus the abdominal aorta is
+protected to a great extent from the deleterious effects of
+increased pressure. Focal degenerative lesions are, however,
+found in the abdominal aorta.</p>
+
+<p>Changes somewhat analogous to those found in the human
+aorta as the result of intimal proliferations, are produced
+in animals by the toxins of the typhoid bacillus and the
+Streptococcus pyogenes. Clinically, Thayer and Brush
+have found that the arteries of those who have recovered
+from an attack of typhoid fever are more palpable than the
+arteries of average individuals of equal age who have never
+had the disease.</p>
+
+<p>Experimentally, the changes caused by the toxins above
+noted are proliferations of cells in the intima and subintimal
+tissues, and a breaking up of the internal elastic laminæ
+into several parallel layers which stretch themselves among
+the proliferating cells. The diphtheria toxin, on the contrary,
+produces a lesion more like that caused by adrenalin.
+All pathologists are not agreed as to whether the experimental
+lesions produced by blood pressure raising drugs
+are similar to the arteriosclerotic changes in the arteries
+of man.</p>
+
+<p>Some of the work on rabbits has been discredited for the
+reason that arteriosclerosis appears spontaneously in about
+fifteen per cent of all laboratory rabbits. Furthermore,
+comparatively young rabbits have been found with arteriosclerosis.
+O. Loeb, however, denies this. He has examined
+in the course of eight years 483 healthy rabbits and never
+found arterial changes. The spontaneous lesions can not
+be distinguished histologically from those due to adrenalin.<span class="pagenum"><a name="Page_54" id="Page_54">[54]</a></span>
+They differ macroscopically in that the lesion is usually
+limited to a few foci near the origin of the aorta.</p>
+
+<p>Lesions produced by the drugs enumerated above represent
+one type of experimental arteriosclerosis. More interesting
+and important are the experiments which seem to
+show that high tension alone is capable of producing lesions
+in arteries which in all respects correspond to Adami's
+strain hypertrophy and overstrain theory. It has been
+shown that when a portion of vein is placed under conditions
+of high arterial pressure, as in a transplantation of a
+portion of vein into a carotid artery, the vein undergoes
+marked connective tissue hypertrophy which includes all
+the coats. This is evidently strain hypertrophy. Again, it
+has been demonstrated that by suspending a previously
+healthy rabbit by the hind legs for three minutes daily over
+a period of three to four months, there results hypertrophy
+of the heart with thinning and dilatation of the arch and the
+upper part of the thoracic aorta. No change was found in
+the abdominal aorta. The carotids, however, were larger
+than normal and they showed typical intimal sclerosis with
+connective tissue thickening.</p>
+
+<p>Neither I nor others have been able to confirm this experiment,
+so it is very doubtful whether mechanical pressure
+alone can produce true arteriosclerosis. Some evidence
+is adduced to bear on this point, however, in the fact
+that sclerosis of the pulmonary artery follows often upon
+mitral stenosis. Yet we do not know but that factors other
+than pressure alone produce the arteriosclerotic change in
+such cases, so we are forced back on our conclusion expressed
+above; viz., that experiments on animals fail to
+sustain the purely mechanical origin of arteriosclerosis.</p>
+
+<p>The changes in the intima constitute the effort on the
+part of nature to repair a defect in the vessel wall which is
+to compensate for the weakened media and the widened
+lumen. This applies only to true arteriosclerosis, not to<span class="pagenum"><a name="Page_55" id="Page_55">[55]</a></span>
+the condition produced experimentally by the toxin of the
+typhoid bacillus, for example.</p>
+
+<p>When an artery loses its elasticity and begins to have
+connective tissue deposited in its walls, the pressure of the
+blood stretches the vessel which is now no longer capable of
+retracting when the pulse wave has passed, and, in consequence,
+the artery is actually lengthened. This necessarily
+causes a tortuosity of the vessel which can be easily seen in
+such arteries as the temporals, brachials, radials, and other
+arteries near the surface of the skin.</p>
+
+<p>The exact mechanism of increase of blood pressure is not
+satisfactorily explained. The smaller arteries all over the
+body are supplied with vasoconstrictor and vasodilator
+nerve fibers from the sympathetic nervous system. Normally
+when an organ is actively functionating the vessels
+are widely dilated and the flow of blood is rapid. Among
+the many factors which influence blood pressure and blood
+supply must be reckoned the psychic.</p>
+
+<p>We know that normally there is a certain resistance
+offered to the propulsion of blood through the arteries by
+the contraction of the heart. This tonus is essential to the
+maintenance of an equalized circulation. The muscular
+arterioles throughout the body by their tonus serve to keep
+up the normal blood pressure and to distribute the blood
+evenly to the various organs. Contraction of a large area
+of arterioles increases the blood pressure and, strangely
+enough, the arteries respond to increased arterial pressure,
+not by dilatation, but by contraction. It would appear that
+rise of blood pressure tends to throw increased work upon
+the musculature of the arterioles. This may be sufficient
+only to cause them to hypertrophy, but further strain may
+easily lead to exhaustion and to dilatation. "As a result
+strain hypertrophy of the intima shows itself with thickening,
+and it may also be of the adventitia, resulting in chronic
+periarteritis. And now with continued degeneration of the
+medial muscle in those muscular arteries, fibrosis of the<span class="pagenum"><a name="Page_56" id="Page_56">[56]</a></span>
+media may also show itself. I would thus regard muscular
+hypertrophy of the arteries and fibrosis of the different
+coats as different stages in one and the same process.
+Whether these peripheral changes are the more marked, or
+the central, depends upon the relative resisting power of
+the elastic and muscular arteries of the individual respectively."
+(Adami.)</p>
+
+<div class="figcenter bord" style="width: 417px;">
+<a name="Cross_section_of_small_artery_in_the_mesentery" id="Cross_section_of_small_artery_in_the_mesentery"></a>
+<img src="images/fig_010.png" width="417" height="500" alt="Fig. 10.&mdash;Cross-section of a small artery in the mesentery. Note that the vessel appears
+capable of being much widened. The internal elastic lamina is thrown into folds
+somewhat resembling the convolutions of the brain. Note also that the middle coat
+of the artery is composed almost entirely of muscle. The enormous number of such
+vessels in the mesentery and intestines explains the ability of the splanchnic area to
+accommodate the greater part of the blood in the body. Universal constriction of these
+vessels would naturally render the intestines anemic. The vasomotor control of these
+vessels plays an important rôle in the distribution of the blood. Small arteries in the
+skin and in other organs, possibly the brain, have a similar function. (Microphotograph,
+highly magnified&quot;.)" title="Fig. 10.&mdash;Cross-section of a small artery in the mesentery... (Microphotograph,
+highly magnified.)" />
+<span class="caption">Fig. 10.&mdash;Cross-section of a small artery in the mesentery. Note that the vessel appears
+capable of being much widened. The internal elastic lamina is thrown into folds
+somewhat resembling the convolutions of the brain. Note also that the middle coat
+of the artery is composed almost entirely of muscle. The enormous number of such
+vessels in the mesentery and intestines explains the ability of the splanchnic area to
+accommodate the greater part of the blood in the body. Universal constriction of these
+vessels would naturally render the intestines anemic. The vasomotor control of these
+vessels plays an important rôle in the distribution of the blood. Small arteries in the
+skin and in other organs, possibly the brain, have a similar function. (Microphotograph,
+highly magnified.)</span>
+</div>
+
+<p>It is conceivable that in one section of the body the vessels<span class="pagenum"><a name="Page_57" id="Page_57">[57]</a></span>
+may be markedly contracted, but if there is dilatation in
+some other part there will be no increased work on the part
+of the heart, and theoretically, there should be no rise of
+blood pressure. The vascular system, however, while likened
+to a system of rubber tubes, must be regarded as a
+very live system, every subsystem having the property of
+separate control.</p>
+
+<p>For blood tension to be raised all over the body, conditions
+must favor the generalized contraction of a large area
+of arterioles. Some authors consider that the so-called
+viscosity of the blood also is a factor in the causation of
+increased tension. The usual cause for the high tension is
+probably the presence in the blood of some poisonous substance.</p>
+
+<p>It is held by some authors that the great splanchnic area
+is capable of holding all the blood in the body and in respect
+of its liability to arteriosclerosis, it is second only to the
+aorta and coronary arteries. The enormous area of the
+skin vessels could probably contain most of the blood.
+The tone of the vasoconstrictor center controls the distribution
+of blood throughout the body. The fact that the vessels
+in the splanchnic area are frequently attacked by
+sclerotic changes means, as a rule, increase of work for
+the heart.<a name="FNanchor_1_1" id="FNanchor_1_1"></a><a href="#Footnote_1_1" class="fnanchor">[1]</a> The resistance offered to the passage of the
+blood must be great and signifies that, for blood to travel at
+the same rate that it did before the resistance set in, more
+power must be expended in its propulsion. In other words,
+the heart must gradually become accustomed to the changed
+conditions, and, as a result of increased work, the muscle
+hypertrophies. (See Fig. 11.)</p>
+
+<div class="figcenter" style="width: 500px;">
+<a name="Enormous_hypertrophy_of_left_ventricle" id="Enormous_hypertrophy_of_left_ventricle"></a>
+
+<img src="images/fig_011.png" width="500" height="357" alt="Fig. 11.&mdash;Enormous hypertrophy of left ventricle probably due to prolonged increased
+peripheral resistance. Note that the whole anterior surface of the heart is occupied
+by the left ventricle. The right ventricle does not appear to be much affected.
+&#215; &#8532;." title="Fig. 11.&mdash;Enormous hypertrophy of left ventricle probably due to prolonged increased
+peripheral resistance. Note that the whole anterior surface of the heart is occupied
+by the left ventricle. The right ventricle does not appear to be much affected.
+&#215; &#8532;." />
+<span class="caption">Fig. 11.&mdash;Enormous hypertrophy of left ventricle probably due to prolonged increased
+peripheral resistance. Note that the whole anterior surface of the heart is occupied
+by the left ventricle. The right ventricle does not appear to be much affected.
+&#215; &#8532;.</span>
+</div>
+
+<p>In diffuse arteriosclerosis accompanied by chronic nephritis
+the heart is always hypertrophied. This is a result, not<span class="pagenum"><a name="Page_58" id="Page_58">[58]</a></span>
+a cause of the condition. In the pure type, there is hypertrophy
+only of the left ventricle without dilatation of the
+chamber. The muscle fibers are increased in number and in
+size, and there are frequently areas of fibrous myocarditis
+due to necrosis caused by insufficient nutrition of parts of
+the muscle. In these cases the coronary arteries share in
+the generalized arteriosclerotic process. The openings of
+the arteries behind the semilunar valves may be very small.
+There is often thickening and puckering of the aortic valves
+and of the anterior leaflet of the mitral valve leading, at
+times, to actual insufficiency of the orifice. Later, when the
+heart begins to weaken, there is dilatation of the chambers
+and loud murmurs result, caused by the inability of the nondistensible
+valves to close the dilated orifices. Until the
+compensation is established, it is impossible to say whether
+or not true insufficiency is present.</p>
+
+<p><span class="pagenum"><a name="Page_59" id="Page_59">[59]</a></span>In senile arteriosclerosis there is the physiologic atrophy
+of the media to be reckoned with. This change has already
+been referred to. When such degeneration has taken place,
+the normal blood pressure may be sufficient to cause stretching
+of the already weakened media with or without hypertrophy
+of the intima. The arteries may be so lined with
+deposits of calcareous matter that they appear as pipe
+stems. More frequently there are rings of calcified material
+placed closely together or irregular beading, giving to the
+palpating finger the impression of feeling a string of very
+fine beads. The arteries are often tortuous, hard, and are
+absolutely nondistensible. At times no pulse wave can be
+felt.</p>
+
+<p>The larger arteries such as the brachials and femorals
+are most affected. The walls become thinned and show
+cracks, and areas apparently, but not actually denuded of
+intima. Yellowish-white, irregular, raised plaques are scattered
+here and there. Interspersed among these areas are
+irregularly shaped clean-cut ulcers having as a rule a
+smooth base, and frequently on the base is a thin plate of
+calcified matter. The color of these denuded areas is usually
+brownish red or reddish brown. White thrombi may
+be deposited on these areas. The danger of an embolus
+plugging one of the smaller arteries is great and probably
+happens more often than we think. The collateral circulation
+is able to supply the thrombosed area. Should the
+thrombus be on the carotid arteries, hemiplegia may result
+from cerebral embolism. On microscopic examination of
+the arteries there is seen extreme degeneration of all the
+coats, the degeneration of the media leading almost to an
+obliteration of that coat. On seeing such arteries as these
+one wonders how the circulation could have been maintained
+and the organs nourished. Senile atrophy of the
+internal organs naturally goes hand in hand with such
+arterial changes.</p>
+
+<p>There is, as a rule, no increase in arterial tension; on the<span class="pagenum"><a name="Page_60" id="Page_60">[60]</a></span>
+contrary, the pressure is apt to be low. This is readily
+understood when the heart is seen. This organ is small,
+the muscle is much thinned, it is flabby and of a brownish
+tint, the so-called "brown atrophy." Microscopically,
+there is seen to be much fragmentation of the fibers with
+a marked increase of the brown pigment granules which
+surround the cell nuclei. Cases are seen, however, in which
+blood pressure increases as the patient grows older. The
+hearts in such cases are more or less hypertrophied and
+show extensive areas of fibroid myocarditis.</p>
+
+<p>From what has been said, it follows that hypertension
+alone may be the cause of arteriosclerosis; that certain
+poisons in the blood which attack the media and cause it
+to degenerate and weaken cause arteriosclerosis without
+increased blood pressure; that the normal blood pressure
+may be, for the artery which is physiologically weakened in
+an individual over fifty, really hypertension, and arteriosclerosis
+may result. Our observations lead us to believe
+that the process is at bottom one and the same. The different
+types noted clinically depend upon the nature of the
+etiologic factors and the kind of arterial tissue with which
+the individual is endowed. This view at least brings some
+order out of previous chaos, and corresponds well with our
+present knowledge of the disease.</p>
+
+<p>There are many cases of arteriosclerosis which lead to
+definite interference with the closure of the valves of the
+heart, particularly the aortic and the mitral. It has been
+said that puckerings of the valves frequently occur (Fig.
+12). This arteriosclerotic endocarditis at times leads to
+very definite heart lesions, chiefly aortic or mitral insufficiency,
+or both with, at times, murmurs of a stenotic character
+at the base. There is rarely true aortic stenosis,
+however. The murmur is caused by the passage of the
+blood over the roughened valves and into the dilated aorta.
+Aortic stenosis is one of the rarest of the valvular lesions
+affecting the valves of the left heart, and should be diagnosed<span class="pagenum"><a name="Page_61" id="Page_61">[61]</a></span>
+only when all factors, including the typical pulse
+tracings, are taken into consideration.</p>
+
+<div class="figcenter" style="width: 500px;">
+<a name="Aortic_incompetence_with_hypertrophy_and_dilatation_of_left_ventricle" id="Aortic_incompetence_with_hypertrophy_and_dilatation_of_left_ventricle"></a>
+<img src="images/fig_012.png" width="500" height="451" alt="Fig. 12.&mdash;Aortic incompetence with hypertrophy and dilatation of left ventricle, the
+result of arteriosclerosis affecting the aortic valves. Note how the valves have been curled,
+thickened, and shortened, the edges of valves being a half inch below the upper points
+of attachment. The anterior coronary artery is shown, the lumen narrowed. (Reduced
+one-half.)" title="Fig. 12.&mdash;Aortic incompetence with hypertrophy and dilatation of left ventricle, the
+result of arteriosclerosis affecting the aortic valves.... (Reduced
+one-half.)" />
+<span class="caption">Fig. 12.&mdash;Aortic incompetence with hypertrophy and dilatation of left ventricle, the
+result of arteriosclerosis affecting the aortic valves. Note how the valves have been curled,
+thickened, and shortened, the edges of valves being a half inch below the upper points
+of attachment. The anterior coronary artery is shown, the lumen narrowed. (Reduced
+one-half.)</span>
+</div>
+
+<p>The kidneys, as a rule, show extensive sclerosis. They
+are small, firm, and contracted and not always to be differentiated
+from the contracted kidneys of chronic inflammation.
+The lesions of the arteriosclerotic kidney are due
+to narrowing and eventual obstruction of the afferent vessels.
+The organs are usually bright red or grayish red in
+color. At times there is marked fatty degeneration of
+cortex and medulla, giving to them a yellowish streaking.
+The capsule is here and there adherent, the cortex is much
+thinned and irregular. The surface presents a roughly<span class="pagenum"><a name="Page_62" id="Page_62">[62]</a></span>
+granular appearance. The glomeruli stand out as whitish
+dots and the sclerosed arteries are easily recognized, as
+their walls are much thickened. The process does not, as
+a rule, affect the whole kidney equally, but rather affects
+those portions corresponding to the interlobular arteries.
+The replacement of the normal kidney tissue by connective
+tissue and the resulting contraction of this latter tissue
+leads to the formation of scars. As the process is not regular,
+the scarring is deeper in some places than in others,
+with the result that localized rather sharply depressed
+areas appear on the surface. The pelvis is relatively large
+and is filled with fat. The renal artery is often markedly
+sclerosed and the whole process may be due to localized
+thickening of the artery, or as part of a general arteriosclerosis.
+The latter is the more frequent. Microscopically,
+it is seen that the tubules are atrophied, the Bowman's
+capsules are, as a rule, thickened, and the glomeruli are
+shrunken or have been replaced by fibrous tissue. In places
+they have fallen out of the section. There is marked proliferation
+of connective tissue in cortex and medulla. The
+arterioles are thickened, the sclerosis being either of the
+intima or media or of both. There is even occlusion of
+many arterioles.</p>
+
+<p>Changes in other organs as the result of arteriosclerosis
+of their afferent vessels occur, but are not so characteristic
+as in the kidney. In the brain the result of gradual thickening
+of the arterioles is a diminished blood supply, softening
+of the portion supplied by the artery, and later a connective
+tissue deposit. The occurrence of thrombi is favored
+and, now and again, a thrombus plugs an artery
+which supplies an important and even vital part of the
+brain. The arteries of the brain are end arteries, hence
+there is no chance for collateral circulation. It is therefore
+evident how serious a result may follow the disturbance
+in or actual deprivation of blood supply to any of the
+brain centers or to the internal capsule.</p>
+<p><span class="pagenum"><a name="Page_63" id="Page_63">[63]</a></span></p>
+
+<h4>Arteriosclerosis of the Pulmonary Arteries</h4>
+
+<p>There have been a number of cases of sclerosis of the
+pulmonary arteries, either alone, or associated with general
+systemic arteriosclerosis.</p>
+
+<p>A primary and a secondary form are recognized, the former
+in conjunction with congenital malformations of the
+heart, the latter as the result of severe infection or of mitral
+stenosis. These two causes seem to be the most important
+in the production of the arterial changes. The cases
+thus far described have revealed widespread thickening
+of the pulmonary arteries. If one may judge by the description
+of the pathologic changes, the condition is quite
+similar to that produced in a vein by transplantation along
+the course of an artery. The diffuse form with connective
+tissue thickening of all coats has been generally described.
+There is also obliterating endarteritis of the smaller vessels.
+In the etiology of the condition severe infection seems
+to play a prominent rôle. The constant presence of right
+ventricular hypertrophy is interesting, the heart dullness
+extends, as a rule, far to the right of the sternum. In some
+of the cases no demonstrable changes were observed in the
+bronchial arteries or in the pulmonary veins.</p>
+
+<p>Sanders has described a case of primary pulmonary arteriosclerosis
+with hypertrophy of the right ventricle.</p>
+
+<p>Recently Warthin<a name="FNanchor_2_2" id="FNanchor_2_2"></a><a href="#Footnote_2_2" class="fnanchor">[2]</a> has reported a case of syphilitic
+sclerosis of the pulmonary artery which places the lesion
+in exactly the same category as that of syphilis in the systemic
+arteries. There was also aneurysm of the left upper
+division present and, to settle the etiologic nature of the
+process, Spirochete pallida were found in the wall of the
+aneurysm sac and in that of the pulmonary artery. The
+microscopic picture in the pulmonary artery could not be
+told from that in a syphilitic aorta.</p>
+<p><span class="pagenum"><a name="Page_64" id="Page_64">[64]</a></span></p>
+
+<h4>Sclerosis of the Veins</h4>
+
+<p>Phlebosclerosis not infrequently occurs with arteriosclerosis.
+It is seen in those cases characterized by high blood
+pressure. Such increased pressure in the veins is due, for
+example, to cirrhosis of the liver which affects the portal
+circulation, or to mitral stenosis which affects the pulmonary
+veins. The affected vessels are usually dilated. The
+intima shows compensatory thickening especially where the
+media is thinned. As a rule all the coats are involved in the
+connective tissue thickening. Occasionally hyaline degeneration
+or calcification of the new-formed tissue is seen.
+"Without existing arteriosclerosis the peripheral veins
+may be sclerotic usually in conditions of debility, but not infrequently
+in young persons." (Osler.)</p>
+
+<p>In many cases of arteriosclerosis, the pathologic changes
+are not confined to the arteries, but are found in the veins
+as well as in the capillaries. Such cases could be called
+angiosclerosis.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_65" id="Page_65">[65]</a></span></p>
+<h2><a name="CHAPTER_III" id="CHAPTER_III"></a>CHAPTER III.</h2>
+
+<h3>PHYSIOLOGY OF THE CIRCULATION</h3>
+
+
+<p>No attempt will be made to cover the entire subject of
+the physiology of the circulation. Only in so far as it relates
+to arteriosclerosis and blood pressure and has a bearing
+on the probable explanation of blood pressure phenomena
+will it be discussed.</p>
+
+<p>"The heart and the blood vessels form a closed vascular
+system, containing a certain amount of blood. This blood
+is kept in endless circulation mainly by the force of the
+muscular contractions of the heart; but the bed through
+which it flows varies greatly in width at different parts of
+the circuit, and the resistance offered to the moving blood
+is very much greater in the capillaries than in the large
+vessels. It follows, from the irregularities in size of the
+channels through which it flows, that the blood stream is
+not uniform in character throughout the entire circuit&mdash;indeed,
+just the opposite is true. From point to point in
+the branching system of vessels the blood varies in regard
+to its velocity, its head of pressure, etc. These variations
+are connected in part with the fixed structure of the system
+and in part are dependent upon the changing properties of
+the living matter of which the system is composed." (W.
+H. Howell.)</p>
+
+<p>If the vascular system were composed of a central pump,
+projecting at every stroke a given amount of liquid into
+a series of rigid tubes, the aggregate cross sections of which
+were equal to the cross section of the main pipe, then the
+velocity at the openings would be the same as at the source
+(making allowances for friction). The problem would then
+be a simple one. In the circulation of the blood no such
+simple condition obtains. The capillary beds is an enormous<span class="pagenum"><a name="Page_66" id="Page_66">[66]</a></span>
+area through which the blood flows slowly. From the
+time the blood is thrown into the aorta the velocity begins
+to diminish until it reaches its minimum in the capillaries.
+In no two persons is the initial velocity at the heart the
+same, nor in the same person is it the same at all times of
+day. The size of the heart, the actual strength of the
+muscle, the amount of blood ejected at every beat, and the
+size and elasticity of the aorta are some of the factors which
+determine the velocity of blood at the aortic orifice. When
+to these factors are added the differences in arterial tissue,
+the activity or resting stage of the various organs, etc., the
+question becomes exceedingly complicated. In spite of
+these many disturbing elements, attempts more or less successful
+have been made to estimate the velocity of the blood
+in animals. Thus, in the carotid of the horse the velocity
+was found to be 300 mm. per second (Volkman) and 297
+mm. (Chauveau); in the carotid of the dog, 260 mm.
+(Vierordt). In the jugular vein of the dog Vierordt found
+the velocity to be 225 mm. per second. These figures do
+not represent the actual velocity of the blood in all horses
+or all dogs, but they do give us some general idea of the
+rate of flow of the blood. For man it has been calculated
+that the velocity in the aorta is about 320 mm. per second.
+The velocity is not uniform in the large arteries, where at
+every heart beat there is a sudden increase followed by a
+decrease as the heart goes into diastole. The farther away
+from the heart the measurements are made the more even
+is the flow.</p>
+
+<p>Observations by W. H. Luedde with the Zeiss binocular
+corneal microscope on the rate of flow in the conjunctival
+capillaries must modify somewhat our former conceptions.
+He finds that "The rate varies in the different arteries,
+capillaries, and veins from a barely perceptible motion to
+a little more than 1 mm. per second. Further, some parts
+of the capillary network are ordinarily supplied with blood
+elements only occasionally. This is shown by the passage<span class="pagenum"><a name="Page_67" id="Page_67">[67]</a></span>
+of a column of corpuscles along a certain line, followed
+after an interval of seconds, during which no corpuscles
+pass, by another column in the same line as before."</p>
+
+<p>The vessels of the conjunctiva probably are quite like
+superficial vessels in the skin and mucous membranes.
+Therefore, we must be free to admit that the circulation
+in them is not absolutely steady. Luedde found further that
+in syphilitics there were tortuosities, irregularities, minute
+aneurysmal dilatations and even obliterations of capillaries.
+Some of the changes occurred as early as one month after
+infection.</p>
+
+<p>The rate in the capillaries of man is estimated to be between
+0.5 mm. and 0.9 mm. per second. As the blood is
+collected into the veins and the bed becomes smaller, the
+velocity increases until at the heart it is almost the same
+as in the aorta. That the velocity could not be exactly the
+same is evident from the fact that the cross section of the
+veins, which return the blood to the right auricle, is greater
+than is the cross section of the aorta.</p>
+
+<p>The volume of the bed is subject to rapid and wide
+fluctuations, which are dependent on many causes, both
+physiologic and pathologic. The call of an actively functionating
+organ or group of organs causes a widening
+of a more or less extensive area, and the velocity necessarily
+varies. In states of great relaxation of the vessels there
+may be a capillary pulse. In order to force blood at the
+same rate through dilated vessels as through normal vessels,
+there must be more blood or there must be a more
+rapid contraction of the central pump. What actually
+happens, as a rule, is an increase in the rate of the heart
+beat. There are conditions&mdash;such, for example, as aortic
+insufficiency&mdash;where actually more blood is thrown into
+the circulation at every beat, so that the rate is not
+changed.</p>
+
+<p>It has been calculated that the average amount of blood
+thrown into the aorta at every systole of the heart is from<span class="pagenum"><a name="Page_68" id="Page_68">[68]</a></span>
+50 to 100 c.c. This is forcibly ejected into a vessel already
+filled (apparently) with blood. In order to accommodate
+this sudden accession of fluid, the aorta must expand. The
+aortic valves close, and during diastole the blood is forced
+through the vascular system by the forcible, steady contraction
+of the highly elastic aorta. Other large vessels which
+branch from the aorta also have a part in this steady propulsion
+of blood. From seventy to eighty times a minute
+the aorta is normally forcibly expanded to accommodate
+the charge of the ventricle. It is not difficult to understand
+the great frequency of patches of sclerosis in the arch
+when these facts are borne in mind.</p>
+
+<p>What relationship the viscosity of the blood has to the
+rate and volume of flow is not fully understood. As yet
+there is not much known about the subject, and no one has
+devised a satisfactory means of measuring the viscosity.
+It is thought by some that an increased viscosity assists in
+producing an increased amount of work for the heart.</p>
+
+
+<h4>Blood Pressure</h4>
+
+<p>Blood pressure is the expression used for a series of
+phenomena resulting from the action of the heart. As every
+heart beat is actual work done by the heart in overcoming
+resistance to the outflow of blood, this force is approximately
+measurable in a large artery such as the brachial.
+It has been determined that the pressure in the brachial
+artery is almost equal to the intraventricular pressure in
+the left ventricle. In animals it is easy to attach manometers
+to the carotid artery and to measure the blood pressure
+accurately. Formerly the method consisted in attaching
+a tube and allowing the blood to rise in the tube. The
+height to which the blood rose measured the maximum pressure.
+This is a crude method and has been replaced by
+the U-tube of mercury with connection made to the artery
+by saline or Ringer's solution. This apparatus is familiar
+to all physiologists.</p>
+
+<p><span class="pagenum"><a name="Page_69" id="Page_69">[69]</a></span>In man the measurement is most conveniently made from
+the brachial artery. There is some difference in the pressure
+in the femoral and the brachial and some use both
+arteries. However, the difficulty of adjusting instruments
+to the upper leg, the great force which must be used to compress
+the femoral artery and the relative inaccessibility of
+the leg as compared to the arm, make the leg an inconvenient
+part for use in blood pressure determinations. It is
+not to be recommended.</p>
+
+<p>Blood pressure is a valuable aid in diagnosis and of material
+help in many cases in prognosis, but it is not infallible
+neither can it be used alone to diagnose a case. Blood
+pressure is only one of many links in a chain of evidence
+leading to diagnosis. It has been badly used and much
+abused. It has been condemned unjustly when it did not
+furnish <i>all</i> the evidence. It has been made a fetish and
+worshipped by both doctors and patients. A sane conception
+of blood pressure must be widely disseminated lest
+we find it being discarded altogether.</p>
+
+<p>Blood pressure consists of more than the estimation of
+the systolic pressure. The blood pressure picture consists
+of (1) the systolic pressure, (2) the diastolic pressure, (3)
+the pulse pressure which is the difference between the
+systolic and diastolic pressure, (4) the pulse rate. Expressed
+in the literature it should read thus: 120-80-40; 72.
+That tells the whole story in a brief, accurate form. This
+is recommended in history reporting. It must be ever kept
+in mind that a blood pressure reading represents the work
+of the heart at the <i>moment when it was taken</i>. Within a
+few minutes the pressure may vary up or down. There is
+no normal pressure as such, but an average pressure for
+any group of people of the same age living under similar
+conditions. The habit of speaking of any systolic figure as
+normal should be broken. A pressure picture may be normal
+but a systolic reading, whatever it may be, is not accurately
+designated as normal. This distinction is worth
+insisting upon.</p>
+<p><span class="pagenum"><a name="Page_70" id="Page_70">[70]</a></span></p>
+
+<h4>Blood Pressure Instruments</h4>
+
+<p>There are several instruments which are in common use
+for the purpose of recording blood pressure in man.</p>
+
+<p>Historically, the determination of blood pressure for man
+began with the attempt of K. Vierordt in 1855 to measure
+the blood pressure by placing weights on the radial pulse
+until this was obliterated. The first useful instrument,
+however, was devised by Marcy in 1876. He placed the
+hand in a closed vessel containing water connected by tubing
+with a bottle for raising the pressure and by another
+tube with a tambour and lever for recording the size of the
+pulse waves. He maintained that when pressure on the
+hand was made, the point where oscillations of the lever
+ceased was the maximal pressure, the point where the oscillations
+of the recording lever was largest, was the minimal
+pressure.</p>
+
+<p>This pioneer work was practically forgotten for twenty-five
+years. It was not until 1887 that V. Basch devised an
+instrument which was used to some extent. This instrument
+recorded only maximum pressure. It consisted of a
+small rubber bulb filled with water communicating with a
+mercury manometer. The bulb was pressed on the radial
+artery until the pulse below it was obliterated and the
+pressure then read off on the column of mercury. V. Basch
+later substituted a spring manometer for the mercury
+column. Potain modified the apparatus by using air in the
+bulb with an aneroid barometer for recording the pressure.
+These instruments are necessarily grossly inaccurate.
+Moreover, they do not record the diastolic pressure.</p>
+
+<p>In 1896 and 1897 further attempts were made to record
+blood pressure by the introduction of a flat rubber bag
+encased in some nonyielding material, which was placed
+around the upper arm. Riva-Rocci used silk, while Hill
+and Barnard used leather. The latter used a bulb or
+Davidson syringe to force air into the cuff around the arm<span class="pagenum"><a name="Page_71" id="Page_71">[71]</a></span>
+and palpated the radial artery at the wrist, noting the point
+of return of the pulse after compression of the upper arm,
+and reading the pressure on a column of mercury in a tube.</p>
+
+<p>Except that the width of the cuff has been increased from
+5 cm. to 12 cm., this is the general principle upon which all
+the blood pressure instruments now in use are based.
+Most of the apparatuses make use of a column of mercury
+in a U-tube to record the millimeters of pressure. As the
+mercury is depressed in one arm to the same extent as it
+is raised in the other arm the scale where readings are made
+is .5 cm. and the divisions represent 2 mm. of mercury but
+are actually 1 mm. apart.</p>
+
+<p>The cuff was made 12 cm. in diameter because it was
+shown (v. Recklinghausen) that with narrow cuffs much
+pressure was dissipated in squeezing the tissues. Janeway
+has shown that with the use of the 12 cm. cuff
+accurate values are obtained independently of the amount
+of muscle and fat around the brachial artery. In other
+words if an actual systolic blood pressure of 140 mm. is
+present in two individuals, the one with a thin arm, the
+other with a thick arm, the instrument will record these
+pressures the same where a 12 cm. arm band is used. We
+need have no fear of obtaining too high a reading when
+we are taking pressure in a stout or very muscular individual.
+Janeway also was the first to call attention to the fact
+that the diastolic or minimal pressure was at the point
+where the greatest oscillation of the mercury took place.
+This is difficult to estimate in many cases as the eye can
+not follow slight changes in the oscillation when the pressure
+in the cuff is gradually reduced. Practically this is
+the case in small pulses.</p>
+
+<p>The Riva-Rocci instrument was modified by Cook. (See
+Fig. 13.) He used a glass bulb containing mercury into
+which a glass tube projected. The bulb was connected by
+outlet and tubing to the cuff and syringe. The glass tube
+was marked off in centimeters and millimeters and for convenience<span class="pagenum"><a name="Page_72" id="Page_72">[72]</a></span>
+was jointed half way in its length. The instrument
+could be carried in a box of convenient size. This
+instrument is fragile and more cumbersome, although
+lighter in weight, than others and is very little used at
+present.</p>
+
+<div class="figcenter" style="width: 500px;">
+<a name="Cooks_modification_of_Riva-Roccis_blood_pressure_instrument" id="Cooks_modification_of_Riva-Roccis_blood_pressure_instrument"></a>
+
+<img src="images/fig_013.png" width="500" height="386" alt="Fig. 13.&mdash;Cook&#39;s modification of Riva-Rocci&#39;s blood pressure instrument." title="Fig. 13.&mdash;Cook&#39;s modification of Riva-Rocci&#39;s blood pressure instrument." />
+<span class="caption">Fig. 13.&mdash;Cook&#39;s modification of Riva-Rocci&#39;s blood pressure instrument.</span>
+</div>
+
+<p>Stanton's instrument (Fig. 14) is practically Cook's
+made more rigid in every way but without the jointed tube.
+The cuff has a leather casing, the pressure bulb is of heavy
+rubber, the glass tube in which the mercury rises is fixed
+against a piece of flat metal and there are stopcocks in a
+metal chamber introduced between the bulb and mercury
+with which to regulate the in- and out-flow of air. The
+pressure can be gradually lowered conveniently without removing
+the pressure bulb.</p>
+
+<div class="figcenter" style="width: 386px;">
+
+<a name="Stantons_sphygmomanometer" id="Stantons_sphygmomanometer"></a>
+
+<img src="images/fig_014.png" width="386" height="500" alt="Fig. 14.&mdash;Stanton&#39;s sphygmomanometer." title="Fig. 14.&mdash;Stanton&#39;s sphygmomanometer." />
+<span class="caption">Fig. 14.&mdash;Stanton&#39;s sphygmomanometer.</span>
+</div>
+
+<p>The most accurate mercury manometer is that of Erlanger.
+(Fig. 15.) The instrument is bulky and is not
+practicable for the physician in practice. The principle is
+that used by Riva-Rocci. There is an extra T-tube introduced<span class="pagenum"><a name="Page_73" id="Page_73">[73]</a></span>
+between the manometer and air bulb connecting with
+a rubber bulb in a glass chamber. The oscillations of this
+are communicated to a Marey tambour and recorded on
+smoked paper revolving on a drum. There is a complicated
+valve which enables the operator to reduce the pressure
+with varying degrees of slowness. The mercury is
+placed in a U-tube with a scale alongside it. The instrument
+is expensive and not as easy to manipulate as its
+advocates would have us believe. Hirschfelder has added
+to the usefulness (as well as to the complexity) of the Erlanger
+instrument, by placing two recording tambours for
+the simultaneous registering of the carotid and venous
+pulses. In spite of its complexity and necessary bulkiness,
+very valuable data are obtained concerning the auricular
+contractions.</p>
+<p><span class="pagenum"><a name="Page_74" id="Page_74">[74]</a></span></p>
+<div class="figcenter" style="width: 362px;">
+<a name="The_Erlanger_sphygmomanometer_with_the_Hirschfelder_attachments" id="The_Erlanger_sphygmomanometer_with_the_Hirschfelder_attachments"></a>
+
+<img src="images/fig_015.png" width="362" height="500" alt="Fig. 15.&mdash;The Erlanger sphygmomanometer with the Hirschfelder attachments by
+means of which simultaneous tracings can be obtained from the brachial, carotid, and
+venous pulses." title="Fig. 15.&mdash;The Erlanger sphygmomanometer with the Hirschfelder attachments by
+means of which simultaneous tracings can be obtained from the brachial, carotid, and
+venous pulses." />
+<span class="caption">Fig. 15.&mdash;The Erlanger sphygmomanometer with the Hirschfelder attachments by
+means of which simultaneous tracings can be obtained from the brachial, carotid, and
+venous pulses.</span>
+</div>
+
+<p>One of the best of the mercury instruments is the Brown
+sphygmomanometer. In this (Fig. 16) the mercury is in
+a closed, all-glass tube so that it can not spill under any<span class="pagenum"><a name="Page_75" id="Page_75">[75]</a></span>
+sort of manipulation. It is in this sense "fool-proof." The
+cuff, however, is poorly constructed. It is too short and
+there are strings to tie it around the arm. I have found
+that this causes undue pressure in a narrow circle and renders
+the reading inaccurate. In the clinic we use this mercury
+instrument with a long cuff like that provided by the
+Tycos instrument.</p>
+
+<div class="figcenter" style="width: 271px;">
+
+<a name="Desk_model_Baumanometer" id="Desk_model_Baumanometer"></a>
+
+<img src="images/fig_016.png" width="271" height="500" alt="Fig. 16.&mdash;Desk model Baumanometer." title="Fig. 16.&mdash;Desk model Baumanometer." />
+<span class="caption">Fig. 16.&mdash;Desk model Baumanometer.</span>
+</div>
+
+<p>The Faught instrument (Fig. 17) is larger than the
+Brown, but is less easily broken and is not too cumbersome<span class="pagenum"><a name="Page_76" id="Page_76">[76]</a></span>
+to carry around. The substitution of a metal air pump for
+the rubber makes the apparatus more durable.</p>
+
+<div class="figcenter" style="width: 483px;">
+
+<a name="Faught_blood_pressure_instrument" id="Faught_blood_pressure_instrument"></a>
+
+<img src="images/fig_017.png" width="483" height="500" alt="Fig. 17.&mdash;The Faught blood pressure instrument. An excellent instrument which is
+quite easily carried about and is not easily broken." title="Fig. 17.&mdash;The Faught blood pressure instrument. An excellent instrument which is
+quite easily carried about and is not easily broken." />
+<span class="caption">Fig. 17.&mdash;The Faught blood pressure instrument. An excellent instrument which is
+quite easily carried about and is not easily broken.</span>
+</div>
+
+<p>The v. Recklinghausen instrument is not employed to
+any extent in this country. It is both expensive and cumbersome,
+and has no advantages over the other instruments.</p>
+
+<p>Several other instruments have been devised and new ones
+are constantly being added to the already large list. With
+those employing mercury the principle is the same. The
+aim is to make an instrument which is easily carried, durable,
+and accurate.</p>
+
+<p>In all the mercury instruments the diameter of the tube
+is 2 mm. One would suppose that there would be noticeable
+differences in the readings of the different mercury
+instruments depending upon the amount of mercury used
+in the tube. By actual weight there is from 35 to 45 gms.
+of mercury in the several instruments. After many trials,
+no noticeable differences in blood pressure readings can be
+made out between a column weighing 35 gm. and one weighing
+45 gm.</p>
+
+<p>There is, however, the inertia of the mercury to be overcome,<span class="pagenum"><a name="Page_77" id="Page_77">[77]</a></span>
+friction between the tube and the mercury, and vapor
+tension. The mercury is therefore not as sensitive to rapid
+changes of pressure in the cuff as a lighter fluid would be.
+The mercury must be clean and the tube dry so that there
+is no more friction than what is inherent between the mercury
+and glass. In making readings on a rapid pulse the
+oscillations of the mercury column are apt to be irregular
+or to cease now and then, due to the fact that the downward
+oscillation coincides with a pulse wave, or an upward oscillation
+receives the impact of two pulse waves transmitted
+through the cuff. Instruments have been devised to obviate
+this difficulty, but they have not come into favor. They are
+usually too complicated and at present can not be recommended.</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Rogers_Tycos_dial_sphygmomanometer" id="Rogers_Tycos_dial_sphygmomanometer"></a>
+
+<img src="images/fig_018.png" width="500" height="341" alt="Fig. 18.&mdash;Rogers&#39; &quot;Tycos&quot; dial sphygmomanometer." title="Fig. 18.&mdash;Rogers&#39; &quot;Tycos&quot; dial sphygmomanometer." />
+<span class="caption">Fig. 18.&mdash;Rogers&#39; &quot;Tycos&quot; dial sphygmomanometer.</span>
+</div>
+
+<p>An instrument devised by Dr. Rogers (the "Tycos")
+has met with considerable popularity. (Fig. 18.) This is
+not an instrument which operates with a spring and lever.
+The instrument is composed essentially of two metal discs
+carefully ground and attached at their circumferences to
+the metal casing below the dial. There is an air chamber
+between these discs through the center of which air is
+forced by the syringe bulb. When air is forced into the
+space between these two discs, they are forced apart to a
+very slight extent, with the highest pressures only 2-3 mm.
+of bulging occurs. From data gathered after extensive use<span class="pagenum"><a name="Page_78" id="Page_78">[78]</a></span>
+for five years these discs were not found to have sprung.
+A lever attached to a cog which in turn is attached to the
+dial needle magnifies to an enormous extent the slightest
+expansion of the discs. Every dial is handmade and every
+division is actually determined by using a U. S. government
+mercury manometer of standard type. No two dials
+therefore are alike in the spacing of the divisions of the
+scale but every one is calibrated as an individual instrument.
+There is no doubt in the author's mind that for the
+general practitioner the instrument has some advantages
+over the mercury instruments. It reveals the slightest
+irregularity in force of the heart beat. The oscillation of
+the dial needle is more accurately followed by the eye than
+is that of the column of mercury. The needle passes directly
+over the divisions of the scale, while with usual mercury<span class="pagenum"><a name="Page_79" id="Page_79">[79]</a></span>
+instruments the scale is an appreciable distance (sometimes
+.5 cm.) from the column of mercury at the side. (Fig.
+19.) The diastolic pressure is more easily read on the<span class="pagenum"><a name="Page_80" id="Page_80">[80]</a></span>
+"Tycos." It is where the maximum oscillation of the needle
+occurs as the pressure is slowly released from the cuff.
+Although it does not appear that this instrument, if properly
+made and standardized, could become inaccurate,
+nevertheless it is advisable to check it every few months
+against a known accurate mercury manometer instrument.</p>
+
+<div class="figcenter" style="width: 297px;">
+
+<a name="Detail_of_the_dial_in_the_Tycos_instrument" id="Detail_of_the_dial_in_the_Tycos_instrument"></a>
+
+<img src="images/fig_019.png" width="297" height="500" alt="Fig. 19.&mdash;Detail of the dial in the &quot;Tycos&quot; instrument." title="Fig. 19.&mdash;Detail of the dial in the &quot;Tycos&quot; instrument." />
+<span class="caption">Fig. 19.&mdash;Detail of the dial in the &quot;Tycos&quot; instrument.</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Faught_dial_instrument" id="Faught_dial_instrument"></a>
+
+<img src="images/fig_020.png" width="500" height="323" alt="Fig. 20.&mdash;Faught dial instrument." title="Fig. 20.&mdash;Faught dial instrument." />
+<span class="caption">Fig. 20.&mdash;Faught dial instrument.</span>
+</div>
+
+<div class="figcenter" style="width: 282px;">
+
+<a name="Detail_of_the_dial_of_the_Faught_instrument" id="Detail_of_the_dial_of_the_Faught_instrument"></a>
+
+<img src="images/fig_021.png" width="282" height="500" alt="Fig. 21.&mdash;Detail of the dial of the Faught instrument." title="Fig. 21.&mdash;Detail of the dial of the Faught instrument." />
+<span class="caption">Fig. 21.&mdash;Detail of the dial of the Faught instrument.</span>
+</div>
+
+<p>Another perfectly satisfactory dial instrument is the
+Faught (Figs. 20 and 21). The general plan of this differs
+in some minor points from the "Tycos." I have compared
+the two and have found no difference in the readings. Both
+can be recommended.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="The_Sanborn_instrument" id="The_Sanborn_instrument"></a>
+
+<img src="images/fig_022.png" width="500" height="246" alt="Fig. 22.&mdash;The Sanborn instrument." title="Fig. 22.&mdash;The Sanborn instrument." />
+<span class="caption">Fig. 22.&mdash;The Sanborn instrument.</span>
+</div>
+
+<p>One or two other cheaper dial instruments are on the
+market. The Sanborn seems to be quite satisfactory. (Fig.
+22.) It is cheaper than the other dial instruments. There
+is this much to be said, no instrument using a spring as resistance
+to measure pressure can be recommended.</p>
+
+
+<h4>Technic</h4>
+
+<p>The same technic applies to all the mercury instruments.
+The patient sits or lies down comfortably. The right or left
+arm is bared to the shoulder, the cuff is then slipped over
+the hand to the upper arm. (See Fig. 23.) At least an inch
+of bare arm should show between the lower end of the cuff
+and the bend of the elbow. The rubber is adjusted so that
+the actual pressure from the bag is against the inner side<span class="pagenum"><a name="Page_81" id="Page_81">[81]</a></span>
+of the arm. The straps are tightened, care being taken not
+to compress the veins. The upper part of the cuff should
+fit more snugly than the lower part. The part of the instrument
+carrying the mercury column is now placed on a
+level surface; the two arms of the mercury in the tube must
+be even, and at <i>0</i> on the scale. With the fingers of one hand
+on the radial pulse, the bag is compressed until the pulse
+is no longer felt. (See Fig. 24.) One should raise the pressure
+from 10-12 mm. above this, and close the stopcock
+between the bulb and the mercury tube. In a good instrument
+the column should not fall. If it does there is a leak
+of air in the system of tubing and arm bag. Now with the
+finger on the pulse, or where the pulse was last felt, gradually
+allow air to escape by turning the stopcock so that
+the column of mercury falls about 2 mm. (one division on
+the scale) for every heart beat or two. One must not allow
+the column of mercury to descend too slowly as it is uncomfortable<span class="pagenum"><a name="Page_82" id="Page_82">[82]</a></span>
+for the patient and introduces a psychic element
+of annoyance which affects the blood pressure. On the
+other hand, the pressure must not be released too rapidly,
+else one runs over the points of systolic and diastolic pressure
+and the readings are grossly inaccurate. It is impossible
+to say how rapidly the mercury must fall. Every operator
+must find that out for himself by practice. The first perceptible
+pulse wave felt beneath the palpating finger at the
+wrist, represents on the scale the systolic pressure. This
+can be seen to correspond to a sudden increase in the magnitude
+of the oscillation of the mercury column. The systolic
+pressure, thus obtained, is from 5-10 mm. lower than the
+real systolic pressure. The more sensitive the palpating
+finger, the more nearly does the systolic pressure reading
+approach that found by using such an instrument as Erlanger's,
+where the first pulse wave is magnified by the
+lever of the tambour.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+<a name="Method_of_taking_blood_pressure_with_a_patient_in_sitting_position" id="Method_of_taking_blood_pressure_with_a_patient_in_sitting_position"></a>
+<img src="images/fig_023.png" width="500" height="417" alt="Fig. 23.&mdash;Method of taking blood pressure with a patient in sitting position." title="Fig. 23.&mdash;Method of taking blood pressure with a patient in sitting position." />
+<span class="caption">Fig. 23.&mdash;Method of taking blood pressure with a patient in sitting position.</span>
+</div>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="Method_of_taking_blood_pressure_with_patient_lying_down" id="Method_of_taking_blood_pressure_with_patient_lying_down"></a>
+
+
+<img src="images/fig_024.png" width="500" height="349" alt="Fig. 24.&mdash;Method of taking blood pressure with patient lying down." title="Fig. 24.&mdash;Method of taking blood pressure with patient lying down." />
+<span class="caption">Fig. 24.&mdash;Method of taking blood pressure with patient lying down.</span>
+</div>
+
+<p>The pressure is now allowed to fall, until the palpating<span class="pagenum"><a name="Page_83" id="Page_83">[83]</a></span>
+finger feels the largest possible pulse wave, which is coincident
+with the greatest oscillation of the mercury. This is
+the diastolic pressure. Beyond this point there is no oscillation
+of the mercury column. The difference between the
+two is the pulse pressure. Thus the pulse is felt after compression
+at 120 on the scale, and the maximum oscillation
+occurs at 80. The systolic pressure is 120 mm., the diastolic
+is 80 mm., and the pulse pressure is 40 mm.</p>
+
+<p>With the "Tycos" or Faught the arm band is snugly
+wound around the arm, the bag next to the skin and the end
+tucked in, so that the whole band will not loosen when air
+is forced into the bag. The cuff is blown up until the pulse
+is no longer felt. One should raise the pressure not more
+than 10 mm. above the point of obliteration of the pulse.
+The valve is then carefully opened so that the needle gradually
+turns toward zero. At the first return of the pulse
+wave felt at the wrist, the needle is sure to give a sudden
+jump. This is the systolic pressure and is read off on the
+scale. The needle is now carefully watched until it shows
+the maximum oscillation. This is the diastolic pressure.
+The difference between the two is, as above, the pulse pressure.</p>
+
+<p>In taking pressure one should take the average of several,
+three or four. Moreover, one must not take consecutive
+readings too quickly and one must be sure that between
+every two readings all the air is out of the cuff and that the
+mercury or dial is at zero. <i>It has been repeatedly shown
+that in a cyanosed arm the systolic pressure is raised so
+that even slight cyanosis between readings must be carefully
+avoided.</i></p>
+
+<p>The only accurate method of determining both the systolic
+and diastolic pressure, but especially the diastolic, is
+by the so-called auscultatory method. (See Fig. 25.) The
+cuff is adjusted in the usual way and one places the bell
+of a binaural stethoscope over the brachial artery from
+one to two centimeters below the lower edge of the<span class="pagenum"><a name="Page_84" id="Page_84">[84]</a></span>
+cuff.<a name="FNanchor_3_3" id="FNanchor_3_3"></a><a href="#Footnote_3_3" class="fnanchor">[3]</a> Care must be taken that the bell is not pressed too
+firmly against the arm and that the edge of the bell nearest
+the cuff is not pressed more firmly than the opposite end.
+For this purpose, one can not use the ordinary Bowles
+stethoscope or any of the other much lauded stethoscopes,
+because the surface of the bell is too large. The
+diameter of the bell must not be more than twenty-five millimeters,
+twenty is still better. It is advisable before beginning
+the observation to locate with the finger the pulse
+in the brachial artery just above the elbow, so that the
+stethoscope may be placed over the course of the artery.
+(Fig. 26.) The first wave which comes through is heard as
+a click, and occurs at a point on the manometer or dial scale
+from 5-10 mm. higher than can usually be palpated at the
+radial artery. This is the true systolic pressure. By keeping<span class="pagenum"><a name="Page_85" id="Page_85">[85]</a></span>
+the bell of the stethoscope over the brachial artery
+while the pressure is falling, one comes to a point when all
+sound suddenly ceases. This is said to be the diastolic pressure.
+This is incorrect as will be shown later.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="Observation_by_the_auscultatory_method_and_a_mercury_instrument" id="Observation_by_the_auscultatory_method_and_a_mercury_instrument"></a>
+
+
+<img src="images/fig_025.png" width="500" height="484" alt="Fig. 25.&mdash;Observation by the auscultatory method and a mercury instrument. One hand
+regulates the stop cock which releases air gradually." title="Fig. 25.&mdash;Observation by the auscultatory method and a mercury instrument. One hand
+regulates the stop cock which releases air gradually." />
+<span class="caption">Fig. 25.&mdash;Observation by the auscultatory method and a mercury instrument. One hand
+regulates the stop cock which releases air gradually.</span>
+</div>
+
+<div class="figcenter bord" style="width: 500px;">
+<a name="Observation_by_the_auscultatory_method_and_a_dial_instrument" id="Observation_by_the_auscultatory_method_and_a_dial_instrument"></a>
+
+<img src="images/fig_026.png" width="500" height="485" alt="Fig. 26.&mdash;Observation by the auscultatory method and a dial instrument. The right
+hand holds the bulb and regulates the air valve." title="Fig. 26.&mdash;Observation by the auscultatory method and a dial instrument. The right
+hand holds the bulb and regulates the air valve." />
+<span class="caption">Fig. 26.&mdash;Observation by the auscultatory method and a dial instrument. The right
+hand holds the bulb and regulates the air valve.</span>
+</div>
+
+
+<h4>Arterial Pressure</h4>
+
+<p>The arterial pressure in the large arteries undergoes extensive
+fluctuations with every heart beat. The maximum
+pressure produced by the systole of the left ventricle of the
+heart is known as the <b>maximum</b> or <b>systolic pressure</b>. It
+practically equals the intraventricular pressure. The minimum
+pressure in the artery, the pressure at the end of diastole,
+is called the <b>diastolic pressure</b>. The difference between
+the systolic and diastolic pressures is known as the
+<b>pulse pressure</b>. There is yet another term known as the
+<b>mean pressure</b>. For convenience, this may be said to be the<span class="pagenum"><a name="Page_86" id="Page_86">[86]</a></span>
+arithmetical mean of the systolic and diastolic pressures.
+Actually, however, this can not be the case, owing to the
+form of the pulse wave, which is not a uniform rise and fall&mdash;the
+upstroke being a straight line, but the downstroke being
+broken usually by two notches. We do not make use of
+the mean pressure in recording results. It is of experimental
+interest and needs only to be mentioned here.</p>
+
+<div class="figcenter" style="width: 500px;">
+<a name="Schema_to_illustrate_decrease_in_pressure" id="Schema_to_illustrate_decrease_in_pressure"></a>
+
+<img src="images/fig_027.png" width="500" height="193" alt="Fig. 27.&mdash;Schema to illustrate the gradual decrease in pressure from the heart to the
+vena cava: (a), arteries; (c), capillaries; (v), veins; (A), aorta, pressure 150 mm.;
+(B), brachial artery, pressure 130 mm.; (F), femoral vein, 20 mm.; (IVC), inferior
+vena cava, 3 mm. (Modified from Howell.)" title="Fig. 27.&mdash;Schema to illustrate the gradual decrease in pressure from the heart to the
+vena cava: (a), arteries; (c), capillaries; (v), veins; (A), aorta, pressure 150 mm.;
+(B), brachial artery, pressure 130 mm.; (F), femoral vein, 20 mm.; (IVC), inferior
+vena cava, 3 mm. (Modified from Howell.)" />
+<span class="caption">Fig. 27.&mdash;Schema to illustrate the gradual decrease in pressure from the heart to the
+vena cava: (a), arteries; (c), capillaries; (v), veins; (A), aorta, pressure 150 mm.;
+(B), brachial artery, pressure 130 mm.; (F), femoral vein, 20 mm.; (IVC), inferior
+vena cava, 3 mm. (Modified from Howell.)</span>
+</div>
+
+<p>It has been shown that the mean pressure is quite constant
+throughout the whole arterial system. The maximum
+pressure necessarily falls as the periphery of the vascular
+system is approached. In general it may be said that
+the minimal pressure is quite constant. Too little attention
+is paid to minimal and pulse pressure. The minimal pressure
+is important, for it gives us valuable data as to the
+actual propulsive force driving the blood forward to the
+periphery at the end of diastole.</p>
+
+<p>It is readily understood how the maximum pressure falls
+as the periphery is approached, until in the arterioles the
+maximum and minimum pressures are about equal. The
+pressure then in these arterioles is practically the same as
+the diastolic pressure. Actually it is a few millimeters
+less. The diastolic blood pressure would, therefore, measure
+the peripheral resistance and, as the maximum for
+systolic pressure represents approximately the intraventricular<span class="pagenum"><a name="Page_87" id="Page_87">[87]</a></span>
+pressure, the difference between the two, the pulse
+pressure, actually represents the force which is driving the
+blood onward from the heart to the periphery. It is hence
+very evident that the mere estimation of the systolic pressure
+gives us but a portion of the information we are
+seeking.</p>
+
+<p>The pulse pressure is subject to wide fluctuations but as
+a rule for any one normal heart it remains fairly constant
+as the rate varies. In a rapidly beating heart the diastole
+is short and the diastolic pressure rises. If the systolic
+pressure does not also rise, as in a normal heart following
+exercise, we will say, the pulse pressure falls. We know
+that when the pulse rate is constant, vasodilatation causes a
+fall in diastolic pressure and a rise in pulse pressure. On
+the contrary, vasoconstriction causes a rise in diastolic
+pressure and a fall in pulse pressure.</p>
+
+<p>It is very probably the case that with two individuals of
+equal age and equal pulse rate, and equal systolic pressure
+of 160 mm., the one with a diastolic pressure of 110 mm.
+and, therefore, a pulse pressure of 50 mm. is much worse
+off than the other with a diastolic pressure of 90 mm. and a
+pulse pressure of 70 mm. The latter may be normal for the
+age of the person especially when certain forms of fibrous
+arteriosclerosis accompanied by enlarged heart are present.</p>
+
+<p>The former is not normal for any age. Low pulse pressure
+usually means a weak vasomotor control and is only
+found in failing circulation or in markedly run down states,
+such as after serious illness or in tuberculosis. Therefore,
+it is most important to estimate accurately the diastolic
+pressure as well as the systolic pressure, for only in this
+way can we obtain any data of value regarding the driving
+power of the heart and the condition of the vasomotor system.
+A high systolic pressure does not necessarily mean
+that a great deal of blood is forced into the capillaries. Actually
+it may mean that very little blood enters the periphery.
+The heart wastes its strength in dilating constricted<span class="pagenum"><a name="Page_88" id="Page_88">[88]</a></span>
+vessels without actually carrying on the circulation adequately.</p>
+
+
+<h4>Normal Pressure Variations</h4>
+
+<p>The systolic pressure varies considerably under conditions
+which are by no means abnormal. Thus, the average
+for men at all ages is about 127 mm. Hg. (All measurements
+are taken from the brachial artery, with the individuals
+in the sitting posture.) For women the average is
+somewhat lower, 120 mm. Hg. The pressure is lowest in
+children. In children from 6-12 years the average systolic
+pressure is 112 mm. Normally, there is a gradual increase
+as age comes on, due, as will be shown in the succeeding
+chapter, to physiologic changes which take place in the
+arteries from birth to old age. In the chart here appended
+is graphically shown the normal variations in the blood
+pressure at different ages compiled from observations made
+on one thousand presumably normal persons. (Fig. 28.)</p>
+
+<div class="figcenter" style="width: 441px;">
+
+<a name="Chart_showing_the_normal_limits_of_variation_in_systolic_blood_pressure" id="Chart_showing_the_normal_limits_of_variation_in_systolic_blood_pressure"></a>
+
+
+<img src="images/fig_028.png" width="441" height="500" alt="Fig. 28.&mdash;Chart showing the normal limits of variation in systolic blood pressure. (After
+Woley.)" title="Fig. 28.&mdash;Chart showing the normal limits of variation in systolic blood pressure. (After
+Woley.)" />
+<span class="caption">Fig. 28.&mdash;Chart showing the normal limits of variation in systolic blood pressure. (After
+Woley.)</span>
+</div>
+
+<p>The diastolic pressure has been estimated to be about 35
+to 45 mm. Hg lower than the systolic pressure, and consequently
+these figures represent the pulse pressure in the
+brachial artery of man. This is equivalent to saying that
+every systole of the left ventricle distends this artery by a
+sudden increase in pressure equal to the weight of a column
+of mercury 2 mm. in diameter and 35 to 45 mm. high. Naturally,
+at the heart the pressure is highest. As the blood
+goes toward the capillary area the pressure gradually decreases
+until, at the openings of the great veins into the
+heart, the pressure is least. At the aorta (A) the pressure
+(systolic) is approximately 150 mm. Hg, at the brachial
+artery (B) it is 130 mm., in the capillary system (C) it is
+30 mm., in the femoral vein (F) it is 20 mm., at the opening
+of the inferior vena cava (I) it is 3 mm.</p>
+
+<p>Attention has been called to the normal systolic pressure
+at different ages. This is not the only cause for variations
+in the blood pressure. Normally, it is greater when in the<span class="pagenum"><a name="Page_89" id="Page_89">[89]</a></span>
+erect position than when seated, and greater when seated
+than when lying down. During the day there are well-recognized
+changes. The pressure is lowest during the
+early morning hours, when the person is asleep. In women
+there are variations due to menstruation. Muscular exercise
+raises the blood pressure markedly. The effect of a
+full meal is to raise the blood pressure. The explanation
+is that during and following a meal there is dilatation of
+the abdominal vessels. This takes blood from other parts
+of the body, provided that the other factors in the circulation<span class="pagenum"><a name="Page_90" id="Page_90">[90]</a></span>
+remain constant. A fall of pressure would necessarily
+occur in the aorta. To compensate for this, there is increased
+work on the part of the heart, which reveals itself
+as increased pressure and pulse pressure. It is well known
+that the interest in the process taken by an individual upon
+whom the blood pressure is estimated for the first time tends
+to increase the rate of the heart and to raise the blood pressure.
+For this reason the first few readings on the instrument
+must be discarded, and not until the patient looks
+upon the procedure calmly can the true blood pressure be
+obtained. As a corollary to this statement, mental excitement,
+of whatever kind, has a marked influence on the
+pressure. The patient must remain absolutely quiet. Raising the head or
+the free arm causes the pressure to rise.
+Another important physiologic variation is produced by
+concentrated mental activity. This tends to hurry the heart
+and increase the force of the beat. In short, it may be
+stated as a general rule that any active functioning of a
+part of the body which naturally requires a great excess of
+blood tends to elevate the blood pressure. At rest the pressure
+is constant. Variations caused by the factors mentioned
+act only transitorily, and the pressure shortly returns
+to normal.</p>
+
+
+<h4>The Auscultatory Blood Pressure Phenomenon</h4>
+
+<p>Since the first description of the auscultatory blood pressure
+sounds by Korotkov in 1905, this method has been more
+and more employed until today it is the standard, recognized
+method of determining the points in the blood pressure
+reading. When one applies the 12 cm. arm band over
+the brachial artery and listens with the bell of the stethoscope
+about one cm. below the cuff directly over the brachial
+artery near the bend of the elbow, one hears an interesting
+series of sounds when the air in the cuff is gradually
+reduced. The cuff is blown up above the maximum pressure.
+As the air pressure around the arm gradually is<span class="pagenum"><a name="Page_91" id="Page_91">[91]</a></span>
+lowered, the series of sounds begins with a rather low-pitched,
+clear, clicking sound. This is the first phase. This
+only lasts through a few millimeters fall when a murmur
+is added and the tone becomes louder. This click and murmur
+phase is the second phase. A few millimeters more of
+drop in pressure and a clear, sharp, loud tone is audible.
+Usually this tone lasts through a greater drop than any of
+the other tones. This is the third phase. Rather suddenly
+the loud, clear tone gives place to a dull muffled tone. In
+general the transition is quite sharp and distinct. This is
+the fourth phase. The tone gradually or quickly ceases
+until no tone is heard. This is the fifth phase (Ettinger.)</p>
+
+<p>The first phase is due to the sudden expansion of the
+collapsed portion of the artery below the cuff and to the
+rapidity of the blood flow. This causes the first sharp
+clicking sound which measures the systolic pressure.</p>
+
+<p>The second, or murmur and sound phase, is due to the
+whorls in the blood stream as the pressure is further released
+and the part of the artery below the cuff begins to
+fill with blood.</p>
+
+<p>The third tone phase is due to the greater expansion of
+the artery and to the lowered velocity in the artery. A
+loud tone may be produced by a stiff artery and a slow
+stream or by an elastic artery and a rapid stream. This
+tone is clear cut and in general is louder than the first
+phase.</p>
+
+<p>The fourth phase is a transition from the third and becomes
+duller in sound as the artery approaches the normal
+size.</p>
+
+<p>The fifth phase, no sound phase, occurs when the pressure
+in the cuff exerts no compression on the artery and the
+vessel is full throughout its length.</p>
+
+<p>It is generally conceded that the sounds heard are produced
+in the artery itself and not at the heart.</p>
+
+<p>The tones vary greatly in different hearts. A very
+strong third tone phase or prolongation of this phase usually<span class="pagenum"><a name="Page_92" id="Page_92">[92]</a></span>
+means that the heart which produces the tone is a
+strongly acting one, although allowances must be made for
+a sclerosed artery in which there is a tendency to the production
+of a sharp third phase.</p>
+
+<p>Weakness of the third phase, as a rule, indicates weakness
+of the heart and this dulling of the third phase may be
+so excessive that no sound is produced. Goodman and
+Howell have carried this method further by measuring the
+individual phases and calculating the percentage of each
+phase to the pulse pressure. Thus, if in a normal individual
+the systolic pressure is 130 mm., the diastolic 85 mm.,
+and the pulse pressure 45 mm., the first phase lasts from
+130 to 116 or 14 mm., the second from 116 to 96, or 20 mm.,
+the third from 96 to 91 or 5 mm., the fourth from 91 to 85, or
+6 mm. The first phase would then be 31.1 per cent of the
+total pulse pressure, the second phase 44.4 per cent, the
+third phase 11.1 per cent, and the fourth phase 13.3 per
+cent. They consider that the second and third phases represent
+cardiac strength (C. S.) and the first and fourth represent
+cardiac weakness (C. W.). They believe that C. S.
+should normally be greater than C. W. In the example
+above C. S.:C. W. = 55.5:44.4. In weak hearts, especially in
+uncompensated hearts, the conditions are reversed and C.
+W. &gt; C. S. This is often the case. As a heart improves
+C. S. again tends to become greater than C. W. They think
+that the phases should be studied in respect to the sounds
+and also to the encroachment of one sound upon another.</p>
+
+<p>These observations are interesting but we have not found
+the division into phases as helpful as it was thought to be.
+We spent a great deal of time on this question. All that
+can be said, in my opinion, is that a loud, long third phase
+is usually evidence of cardiac strength.</p>
+
+<p>A further interesting feature which can be heard in all
+irregular hearts is a great difference in intensity of the individual
+sounds. Goodman and Howell call this phenomenon
+tonal arrhythmia. Irregularities can be made out by<span class="pagenum"><a name="Page_93" id="Page_93">[93]</a></span>
+the auscultatory method which can not be heard at the
+heart.</p>
+
+<p>In anemia the sounds are very loud and clear and do not
+seem to represent the actual strength of the heart.</p>
+
+<p>The general lack of vasomotor tone in the blood vessels
+together with some atrophy and flabbiness of the coats
+probably explains the loud sounds.</p>
+
+<p>In polycythemia the sounds have a curious, dull, sticky
+character and can not be differentiated accurately into
+phases, a condition which was predicted from the knowledge
+of the sharp sounds in anemia.</p>
+
+<p>In not all cases can all phases be made out. It is usually
+the fourth phase which fails to be heard.</p>
+
+<p>In such cases the loud third tone almost immediately
+passes to the fifth phase or no sound phase. The importance
+of this will later be taken up.</p>
+
+<p>"In arteriosclerosis, with hardening and loss of elasticity
+of the vessel walls, the auscultatory phenomena, according
+to Krylow, are apt to be more pronounced, since the back
+pressure at the cuff probably causes some dilatation of the
+vessel above it, while the lumen of the vessel is smaller
+than normal. Both of these factors cause an increased
+rapidity in the transmission of the blood wave when pressure
+in the cuff is released, which in time favors the vibration
+of the vessel walls.</p>
+
+<p>"In high grade thickening of the arterial walls, however,
+especially where calcification had occurred, Fischer
+found that the sounds were distinctly less loud than normal,
+the more so in the arm, which showed the greater
+degree of hardening. According to Ettinger's experience,
+the rapidity of the flow distinctly increases the auscultatory
+phenomenon." (Gittings.)</p>
+
+<p>The sounds depend upon the resonating character of the
+cuff, upon the size and accessibility of the vessel, upon the
+force of the heart beat, and upon the velocity of the blood.</p>
+<p><span class="pagenum"><a name="Page_94" id="Page_94">[94]</a></span></p>
+
+<h4>The Maximum and Minimum Pressures</h4>
+
+<p>The maximum (systolic) pressure is read at the point
+where the first audible click is heard after the cuff is blown
+up and the pressure gradually reduced by means of the
+needle valve in the hand bulb or on the upright of the
+glass containing the mercury. All are agreed upon this
+point. There has been some dispute as to the place where
+the diastolic pressure should be read. Korotkov considered
+that the diastolic pressure should be read at the fourth
+phase when the loud tone suddenly becomes dulled. Others
+held that the diastolic pressure should be read at the fifth
+phase, the absence of all sound. Experiments carried out
+to determine this point were made by me with the assistance
+of Prof. Eyster and Dr. Meek at the Physiological
+Laboratory of the University of Wisconsin. We arranged
+apparatus making it possible to hold the pressure in the
+carotid artery of dogs at maximum or minimum. A femoral<span class="pagenum"><a name="Page_95" id="Page_95">[95]</a></span>
+artery was then dissected and an instrument devised to
+compress the artery with a water jacket. The whole was
+connected up with a kymograph. A time marker was put
+in so as to record the place where changes in sound were
+heard while listening below the cuff around the femoral
+artery. Two sets of records were taken. One with pressure
+greater than minimum pressure and a falling pressure
+over the femoral artery (Fig. 29), the other with
+pressure at zero and gradually raised to minimum pressure
+(Fig. 30). Both sets of records showed the same result;
+viz., that at a point corresponding to the sudden
+change of tone the pressure on the artery corresponded to
+the minimum pressure. It was therefore concluded that
+experimentally in dogs the point where diastolic pressure
+should be read is at the tone change from clear to dull,
+not at the point where all sound disappears.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+<a name="Tracing_of_auscultatory_phenomena" id="Tracing_of_auscultatory_phenomena"></a>
+
+<img src="images/fig_029.png" width="500" height="479" alt="Fig. 29.&mdash;Tracing of auscultatory phenomena. (See explanation in legend of Fig. 30.)" title="Fig. 29.&mdash;Tracing of auscultatory phenomena. (See explanation in legend of Fig. 30.)" />
+<span class="caption">Fig. 29.&mdash;Tracing of auscultatory phenomena. (See explanation in legend of Fig. 30.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Tracings_of_auscultatory_phenomena" id="Tracings_of_auscultatory_phenomena"></a>
+
+
+<img src="images/fig_030.png" width="500" height="260" alt="Fig. 30.&mdash;Figures are to be read from left to right. The top line records the points
+where sounds were heard, the figures above the short vertical lines refer to tones (see
+text). Mx. B. P., maximum blood-pressure. M. B. P., minimum blood-pressure. P. B.,
+pressure bulb recorder. It was impossible to lower and raise this bulb by hand without
+obtaining the great irregular oscillations of the attached lever above the mercury manometer.
+B. L., base line." title="Fig. 30.&mdash;Figures are to be read from left to right. The top line records the points
+where sounds were heard, the figures above the short vertical lines refer to tones (see
+text)...." />
+<span class="caption">Fig. 30.&mdash;Figures are to be read from left to right. The top line records the points
+where sounds were heard, the figures above the short vertical lines refer to tones (see
+text). Mx. B. P., maximum blood-pressure. M. B. P., minimum blood-pressure. P. B.,
+pressure bulb recorder. It was impossible to lower and raise this bulb by hand without
+obtaining the great irregular oscillations of the attached lever above the mercury manometer.
+B. L., base line.</span>
+</div>
+
+<p>Erlanger showed some years ago, that with his instrument,
+the point at which diastolic pressure should be read
+was at the instant when the maximum oscillation of the<span class="pagenum"><a name="Page_96" id="Page_96">[96]</a></span>
+lever suddenly became smaller. While checking up the
+graphic with the auscultatory method using Erlanger's instrument,
+it was noticed that the disappearance of all sound
+did not correspond with the sudden diminution of the oscillation
+of the lever connected with the brachial artery. A
+series of records were carefully made on patients. It was
+seen that during the period of the third tone phase the oscillations
+of the lever on the drum reached a maximum
+(Fig. 31) and remained at approximately the same height
+for some millimeters while the pressure was gradually falling.
+At a point at which the third tone, clear and distinct,
+became dull, there was an appreciable decrease in the height
+of the pulse wave. From this point to the disappearance
+of all sound there was a gradual diminution of the size of
+the pulse waves.<span class="pagenum"><a name="Page_97" id="Page_97">[97]</a></span></p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Clinical_determination_of_diastolic_pressure_fast_drum" id="Clinical_determination_of_diastolic_pressure_fast_drum"></a>
+
+
+<img src="images/fig_031.png" width="500" height="83" alt="Fig. 31.&mdash;Fast drum. Sudden decrease in size of pulse wave at 4, marking the change
+from clear sharp tone to dull tone." title="Fig. 31.&mdash;Fast drum. Sudden decrease in size of pulse wave at 4, marking the change
+from clear sharp tone to dull tone." />
+<span class="caption">Fig. 31.&mdash;Fast drum. Sudden decrease in size of pulse wave at 4, marking the change
+from clear sharp tone to dull tone.</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Clinical_determination_of_diastolic_pressure_slow_drum" id="Clinical_determination_of_diastolic_pressure_slow_drum"></a>
+
+
+<img src="images/fig_032.png" width="500" height="315" alt="Fig. 32.&mdash;Slow drum. Sudden decrease in amplitude at 4." title="Fig. 32.&mdash;Slow drum. Sudden decrease in amplitude at 4." />
+<span class="caption">Fig. 32.&mdash;Slow drum. Sudden decrease in amplitude at 4.</span>
+</div>
+
+<p>For normal pressures the difference between the fourth
+(dull) tone and the fifth (disappearance of all tone) phase,
+amounted to 4 to 10 mm. Occasionally the difference was
+so little, the change from sharp third tone through fourth
+dull tone to disappearance of all sound was so abrupt, that
+one could take the disappearance of all sound as the diastolic
+pressure, with an error of not more than 2 to 4 mm.
+This is within the limits of normal error and practically
+may be used by those who have difficulty in noting the
+change from third to fourth phase. For high pressures,
+however, the difference between fourth and fifth phases was
+never less than 8 mm., and was found as much as 16 mm.
+The diastolic, therefore, should always be taken at the
+fourth phase if possible.</p>
+
+<p>It was found that with the dial instrument the greatest
+fling of the lever corresponded to the third phase and the
+sudden lessened amplitude of the oscillation was at the
+fourth phase and was coincident with the change of tone
+from sharp to dull. Thus the diastolic pressure may be
+read off on the dial scale by watching the fling of the hand
+and with some practice one might acquire considerable accuracy.
+It is better, simpler, and, for most observers, more
+accurate to use the stethoscope and hear the change of
+sound.</p>
+
+
+<h4>The Relative Importance of the Systolic and Diastolic Pressures</h4>
+
+<p>The systolic pressure represents the maximum force of
+the heart. It is measured by noting the first sound audible
+over the brachial artery using the auscultatory method.
+It is the summation of two factors largely; the force expended
+in opening the aortic valves (potential) and the
+force expended from that point to the end of systole, the
+force which is actually driving the blood to the periphery
+(kinetic). To start the blood in motion, the heart must
+overcome a dead weight equal to the sum of all the forces<span class="pagenum"><a name="Page_98" id="Page_98">[98]</a></span>
+holding the aortic valves closed. This sum of factors,
+called the peripheral resistance, must be reached and passed
+by the force of the ventricular beat before one drop of
+blood is set in motion along the aorta. This factor of resistance
+assumes a great importance.</p>
+
+<p>The systolic pressure is always fluctuating as it depends
+upon so many conditions, and the calls of the body except
+during sleep are many and various. In a study of diurnal
+variations in arterial blood pressure it has been found that&mdash;(1)
+A rise of maximum pressure averaging 8 mm. of Hg.
+occurs immediately on the ingestion of food. A gradual
+fall then takes place until the beginning of the next meal.
+There is also a slight general rise of the maximum pressure
+during the day. (2) The range of maximum pressure
+varies considerably in different individuals, but the highest
+and lowest maximum pressures are practically equidistant
+from the average pressure of any one individual.<a name="FNanchor_4_4" id="FNanchor_4_4"></a><a href="#Footnote_4_4" class="fnanchor">[4]</a></p>
+
+<p>The pressure is lowest during sleep and gradually rises
+near the end of sleep, so that on awakening the pressure
+was the same as before sleep.</p>
+
+<p>Physiologically there are many conditions which modify
+the systolic pressure. Sleep, position, meals, exercise, emotional
+states cause often wide fluctuations which may be
+very sudden. It should be constantly borne in mind, that
+the systolic pressure reading which is made, is the maximum
+effort of the heart at that moment only.</p>
+
+<p>The diastolic pressure measures the peripheral resistance.
+It measures the work of the heart, the potential energy, up
+to the moment of the opening of the aortic valves. It is
+the actual pressure in the aorta. The diastolic pressure is
+not very variable; it is not subject to the same influences
+which disturb the systolic pressure. It fluctuates as a rule,
+within a small range. It is not affected by diet, by mental
+excitement, by subconscious psychic influences, to anything
+like the extent to which the systolic pressure is affected by<span class="pagenum"><a name="Page_99" id="Page_99">[99]</a></span>
+the action of these factors. The diastolic pressure is determined
+by the tone in the arterioles and is under the control
+of the vasomotor sympathetic system. Any agent
+which causes chronic irritation of the whole vasomotor system
+produces increase in the peripheral resistance with consequent
+rise in the diastolic pressure. Any agent which
+acts to produce thickening of the walls of the arterioles,
+narrowing their lumina, produces the same effect.</p>
+
+<p>Such states naturally result in increased work on the
+part of the heart, which as a result, hypertrophies in the
+left ventricle. The increase in size and strength is a compensatory
+process in order to keep the tissues supplied
+with their requisite quota of blood. Conversely, paralysis
+of the vasomotor system produces fall of diastolic pressure
+which, if long continued, results in death.</p>
+
+<p>The diastolic pressure then is of importance for the following
+reasons:</p>
+
+<p>1. It measures peripheral resistance.</p>
+
+<p>2. It is the measure of the tonus of the vasomotor system.</p>
+
+<p>3. It is one of the points to determine pulse pressure.</p>
+
+<p>4. Pulse pressure measures the actual driving force, the
+kinetic energy of the heart.</p>
+
+<p>5. It enables us to judge of the volume output, for pulse
+pressure which is only determined by measuring both systolic
+and diastolic pressure, is such an index.</p>
+
+<p>6. It is more stable than the systolic pressure, subject to
+fewer more or less unknown influences.</p>
+
+<p>7. It is increased by exercise.</p>
+
+<p>8. It is increased by conditions which increase peripheral
+resistance.</p>
+
+<p>9. The gradual increase of diastolic pressure means
+harder work for the heart to supply the parts of the body
+with blood.</p>
+
+<p>10. Increased diastolic pressure is always accompanied
+by increased pulse pressure, and increased size of the left
+ventricle, temporarily (exercise) or permanently.</p>
+
+<p><span class="pagenum"><a name="Page_100" id="Page_100">[100]</a></span>11. Decreased diastolic pressure goes hand in hand with
+vasomotor relaxation, as in fevers, etc.</p>
+
+<p>12. Low diastolic pressure is frequently pathognomonic
+of aortic insufficiency.</p>
+
+<p>13. When the systolic and diastolic pressures approach,
+heart failure is imminent either when pressure picture is
+high or low.</p>
+
+<p>When all these factors are taken into consideration, it
+becomes apparent that the diastolic pressure is most important,
+if not the most important part of the pressure
+picture.</p>
+
+<p>Up to within a very brief time all the statistical evidence
+of blood pressure was based on systolic readings alone.
+This data is most valuable and much has been learned as
+to diagnosis and prognosis, but it is a mass of data based
+on a one-sided picture and can not be as valuable as the
+statistics which will undoubtedly be published later when
+all the pressure picture figures can be analyzed.</p>
+
+
+<h4>Pulse Pressure</h4>
+
+<p>The pulse pressure is the actual head of pressure which
+is forcing the blood to the periphery. At every systole a
+certain amount of blood 75-90 c.c. (Howell) is thrown violently
+into an already comfortably filled aorta. The sudden
+ejection of this blood instigates a wave which rapidly
+passes down the arteries as the pulse wave. The elastic
+recoil of the aorta and large arteries near the heart contract
+upon the blood and keep it moving during diastole.
+Normally the blood-vessels are highly elastic tubes with
+an almost perfect coefficient of elasticity. The pulse pressure
+varies under normal conditions from 30 to 50 mm. Hg.
+There is a very definite relationship between the velocity
+of blood and the pulse pressure which is expressed thus;
+velocity = pulse rate &#215; pulse pressure.<a name="FNanchor_5_5" id="FNanchor_5_5"></a><a href="#Footnote_5_5" class="fnanchor">[5]</a></p>
+<p><span class="pagenum"><a name="Page_101" id="Page_101">[101]</a></span></p>
+<p>Further it has been demonstrated that under normal conditions
+and during various procedures&mdash;the pulse pressure
+is a reliable index of the systolic output.<a name="FNanchor_6_6" id="FNanchor_6_6"></a><a href="#Footnote_6_6" class="fnanchor">[6]</a></p>
+
+<p>Increased pulse pressure therefore goes hand in hand
+with greater systolic output. Physiologically this is most
+ideally seen during exercise. Following exercise the pulse
+rate increases, the systolic pressure rises greatly, the diastolic
+slightly or not at all. The pulse pressure therefore is
+increased. The velocity also is much increased. The call
+comes for more blood and the heart responds. In the chronic
+high pulse pressures there are four correlated conditions
+which, so far as I have studied them, are always present.
+These are: (1) An increase in size of the cavity of the left
+ventricle. The ventricle actually by measurement contains
+more blood than normal, and therefore throws out more
+blood at every systole. The volume output is greater per
+unit of time. (2) There is actual permanent increase in
+diameter of the arch of the aorta. This is a compensating
+process to accommodate the increased charge from the left
+ventricle. (3) There are on careful auscultation over the
+manubrium, particularly the lower half, breath sounds
+which vary from bronchial to intensely tubular, depending
+upon the anatomic placing of the aorta, the shape of the
+chest, and the degree of dilatation. Often there is very
+slight impairment of the percussion note as well. (4)
+There is increase in size of all the large distributing arteries,
+carotids, brachials, femorals, renals, celiac axis, etc.,
+with fibrous changes in the media, loss of some elasticity,
+and increase in size of the pulse wave. Increased pulse
+pressure means increased volume output, but does not always
+mean increased velocity. The proper distribution of
+blood to the various organs of the body is regulated by the
+vasomotor system acting upon the small arteries which contain
+considerable unstriated muscle. When fibrous arteriosclerosis
+is present there is loss of elasticity in the distributing<span class="pagenum"><a name="Page_102" id="Page_102">[102]</a></span>
+arteries and a greater volume of blood must be
+thrown out by the ventricle at every systole in order that
+every organ shall have its full quota of blood. A force
+which is sufficient to send blood through elastic normal distributing
+tubes becomes totally insufficient to send the same
+amount of blood through tortuous and more or less inelastic
+tubes.</p>
+
+<p>It is evident then that pulse pressure is exceedingly important.
+It can only be determined by measuring both the
+<i>systolic</i> and <i>diastolic</i> pressure. The pulse rate must also
+be known in order to compute the velocity. It is essential
+to have the whole pressure picture for all cases if correct
+conclusions are to be drawn.</p>
+
+<p>In an irregular heart, especially in the cases due to myocardial
+disease, it is quite impossible to determine the true
+diastolic pressure. One can only approximate it and say
+that the pulse pressure is low or high. As a matter of fact
+the real systolic pressure can not be determined. For this
+figure the place on the scale where most of the beats are
+heard may be taken for the average systolic pressure. No
+one can seriously maintain that he can measure the diastolic
+pressure under all circumstances.</p>
+
+<p>By means of the auscultatory method of measuring blood
+pressure we are able to determine irregularities of force in
+the heart beats more easily than by listening to the heart
+sounds. A pulsus alternans is readily made out. The irregular
+tones heard over the brachial artery in cases of irregular
+heart action have been called "tonal arrhythmias."</p>
+
+
+<h4>Blood Pressure Variations</h4>
+
+<p>A recent study of diurnal variations in blood pressure has
+shown that while the maximum pressure rises after the ingestion
+of food and steadily rises slightly throughout the
+day, the minimum blood pressure is very uniform throughout
+the day, and is little affected by the ingestion and digestion
+of meals. When it is affected, a rise or a fall may<span class="pagenum"><a name="Page_103" id="Page_103">[103]</a></span>
+take place. Throughout the day, it tends to become slightly
+lower. The pulse pressure then is greater towards evening.</p>
+
+<p>Weysse and Lutz in a study of this question draw the following
+conclusions:</p>
+
+<p>1. A rise of maximum pressure averaging 8 mm. of Hg
+occurs immediately on the ingestion of food. A gradual
+fall then takes place until the beginning of the next meal.
+There is also a slight general rise of the maximum pressure
+during the day.</p>
+
+<p>2. The average maximum blood pressure for healthy
+young men in the neighborhood of 20 years of age is 120
+mm. of Hg. This pressure obtains commonly one hour
+after meals. The higher maximum pressures occur immediately
+after meals, and the lower, as a rule, immediately
+before meals.</p>
+
+<p>3. The range of maximum pressure varies considerably in
+different individuals, but the highest and lowest maximum
+pressures are practically equidistant from the average pressure
+of any one individual.</p>
+
+<p>4. The minimum blood pressure is very uniform throughout
+the day, and is little affected by the ingestion and digestion
+of meals. When it is affected a rise or fall may take
+place. There is a tendency for a slight general lowering
+of the minimum pressure throughout the day.</p>
+
+<p>5. The average minimum blood pressure for healthy
+young men in the neighborhood of 20 years of age is 85 mm.
+of Hg. Thus we get an average pulse pressure of 35 mm.
+of Hg.</p>
+
+<p>6. Pulse pressure, pulse rate, and the relative velocity
+of the blood flow are increased immediately upon the ingestion
+of meals. They attain the maximum, as a rule, in
+half an hour, and then decline slowly until the next meal.
+There is a general increase in each throughout the day.</p>
+
+<p>These measurements were made upon persons at rest.
+Almost any form of exercise would have made the variations
+much greater. No account is taken of the psychic
+variations which for the physician are the most important
+to bear in mind. Neglect to take this variation into account
+will inevitably lead to false conclusions.</p>
+<div class="center"><span class="smcap">The Average Diurnal Blood Pressure Record of the Ten Subjects</span></div>
+
+
+
+
+<table summary="Diurnal blood Pressure">
+
+ <tr>
+ <th class="tdouble">TIME</th>
+ <th class="tdouble">MAXIMUM</th>
+ <th class="tdouble">MINIMUM</th>
+ <th class="tdouble">MEAN</th>
+ <th class="tdouble">PULSE</th>
+ <th class="tdouble">PULSE</th>
+ <th class="tdouble">PP x PR</th>
+ <th class="tdouble">NOTES</th></tr>
+
+
+<tr>
+<th class="bdouble bb">&nbsp;</th>
+<th class="bdouble bb">&nbsp;</th>
+<th class="bdouble bb">&nbsp;</th>
+<th class="bdouble bb">&nbsp;</th>
+<th class="bdouble bb">PRESSURE</th>
+<th class="bdouble bb">RATE</th>
+<th class="bdouble bb">&nbsp;</th>
+<th class="bdouble bb">&nbsp;</th>
+</tr>
+
+
+<tr><td align="left">&nbsp;</td><td align="left"><i>mm.</i>Hg</td><td align="left"><i>mm.</i>Hg</td><td align="left"><i>mm.</i>Hg</td><td align="left"><i>mm.</i>Hg</td></tr>
+<tr><td align="left">4:30 p.m.</td><td align="left">119.5</td><td align="left">84.1</td><td align="left">101.8</td><td align="left">35.4</td><td align="left">72.0</td><td align="left">2549</td></tr>
+<tr><td align="left">5:00 p.m.</td><td align="left">117.7</td><td align="left">83.5</td><td align="left">100.6</td><td align="left">34.2</td><td align="left">71.1</td><td align="left">2432</td></tr>
+<tr><td align="left">6:00 p.m.</td><td align="left">118.0</td><td align="left">84.0</td><td align="left">101.0</td><td align="left">34.0</td><td align="left">74.9</td><td align="left">2547</td><td align="left">Before dinner</td></tr>
+<tr><td align="left">6:45 p.m.</td><td align="left">127.2</td><td align="left">88.2</td><td align="left">107.7</td><td align="left">39.0</td><td align="left">78.1</td><td align="left">3046</td><td align="left">After dinner</td></tr>
+<tr><td align="left">7:00 p.m.</td><td align="left">124.7</td><td align="left">87.7</td><td align="left">106.2</td><td align="left">37.0</td><td align="left">76.0</td><td align="left">2812</td></tr>
+<tr><td align="left">7:30 p.m.</td><td align="left">122.0</td><td align="left">83.4</td><td align="left">102.7</td><td align="left">38.6</td><td align="left">76.0</td><td align="left">2934</td></tr>
+<tr><td align="left">8:00 p.m.</td><td align="left">122.4</td><td align="left">85.5</td><td align="left">103.4</td><td align="left">36.9</td><td align="left">71.2</td><td align="left">2527</td></tr>
+<tr><td align="left">8:30 p.m.</td><td align="left">120.0</td><td align="left">85.0</td><td align="left">102.5</td><td align="left">35.0</td><td align="left">69.7</td><td align="left">2439</td></tr>
+<tr><td align="left">9:00 p.m.</td><td align="left">120.5</td><td align="left">84.7</td><td align="left">102.5</td><td align="left">35.8</td><td align="left">65.2</td><td align="left">2334</td></tr>
+<tr><td align="left">9:30 p.m.</td><td align="left">118.2</td><td align="left">84.4</td><td align="left">101.6</td><td align="left">33.8</td><td align="left">64.4</td><td align="left">2177</td></tr>
+<tr><td align="left">7:30 a.m.</td><td align="left">118.4</td><td align="left">87.6</td><td align="left">103.0</td><td align="left">30.8</td><td align="left">70.3</td><td align="left">2165</td></tr>
+<tr><td align="left">8:00 a.m.</td><td align="left">116.4</td><td align="left">86.4</td><td align="left">101.4</td><td align="left">30.0</td><td align="left">69.8</td><td align="left">2094</td><td align="left">Before breakfast</td></tr>
+<tr><td align="left">8:30 a.m.</td><td align="left">124.2</td><td align="left">85.4</td><td align="left">104.8</td><td align="left">38.8</td><td align="left">79.4</td><td align="left">3081</td><td align="left">After breakfast</td></tr>
+<tr><td align="left">9:00 a.m.</td><td align="left">123.8</td><td align="left">84.4</td><td align="left">104.1</td><td align="left">39.4</td><td align="left">84.1</td><td align="left">3313</td></tr>
+<tr><td align="left">10:00 a.m.</td><td align="left">118.2</td><td align="left">83.6</td><td align="left">100.9</td><td align="left">34.6</td><td align="left">70.7</td><td align="left">2446</td></tr>
+<tr><td align="left">11:00 a.m.</td><td align="left">116.2</td><td align="left">84.8</td><td align="left">100.5</td><td align="left">31.4</td><td align="left">67.7</td><td align="left">2126</td></tr>
+<tr><td align="left">12:00 m</td><td align="left">114.4</td><td align="left">83.2</td><td align="left">98.8</td><td align="left">31.2</td><td align="left">66.2</td><td align="left">2065</td><td align="left">Before luncheon</td></tr>
+<tr><td align="left">12:30 p.m.</td><td align="left">122.8</td><td align="left">83.2</td><td align="left">103.0</td><td align="left">39.6</td><td align="left">70.9</td><td align="left">2808</td><td align="left">After luncheon</td></tr>
+<tr><td align="left">1:00 p.m.</td><td align="left">122.3</td><td align="left">82.0</td><td align="left">102.1</td><td align="left">40.3</td><td align="left">79.7</td><td align="left">3212</td></tr>
+<tr><td align="left">2:00 p.m.</td><td align="left">118.4</td><td align="left">81.4</td><td align="left">99.9</td><td align="left">37.0</td><td align="left">77.6</td><td align="left">2871</td></tr>
+<tr><td align="left">3:00 p.m.</td><td align="left">118.8</td><td align="left">82.6</td><td align="left">100.7</td><td align="left">36.2</td><td align="left">75.1</td><td align="left">2719</td></tr>
+<tr><td align="left">4:00 p.m.</td><td align="left">115.8</td><td align="left">82.0</td><td align="left">98.9</td><td align="left">33.8</td><td align="left">71.9</td><td align="left">2420</td></tr>
+<tr><td align="left">5:00 p.m.</td><td align="left">117.2</td><td align="left">83.4</td><td align="left">100.3</td><td align="left">33.8</td><td align="left">69.6</td><td align="left">2352</td></tr>
+<tr><td align="left">6:00 p.m.</td><td align="left">117.4</td><td align="left">84.4</td><td align="left">100.9</td><td align="left">33.0</td><td align="left">72.8</td><td align="left">2402</td><td align="left">Before dinner</td></tr>
+<tr><td align="left">6:45 p.m.</td><td align="left">124.6</td><td align="left">83.1</td><td align="left">103.8</td><td align="left">41.5</td><td align="left">80.4</td><td align="left">3337</td><td align="left">After dinner</td></tr>
+<tr><td align="left">7:00 p.m.</td><td align="left">125.2</td><td align="left">84.2</td><td align="left">104.7</td><td align="left">41.0</td><td align="left">76.1</td><td align="left">3120</td></tr>
+<tr><td align="left">7:30 p.m.</td><td align="left">122.0</td><td align="left">84.0</td><td align="left">103.0</td><td align="left">38.0</td><td align="left">73.7</td><td align="left">2801</td></tr>
+<tr><td align="left">8:00 p.m.</td><td align="left">119.6</td><td align="left">85.0</td><td align="left">102.3</td><td align="left">34.6</td><td align="left">72.3</td><td align="left">2502</td></tr>
+<tr><td align="left">8:30 p.m.</td><td align="left">119.7</td><td align="left">84.0</td><td align="left">101.3</td><td align="left">34.7</td><td align="left">69.0</td><td align="left">2394</td></tr>
+<tr><td align="left">9:00 p.m.</td><td align="left">120.0</td><td align="left">86.2</td><td align="left">103.1</td><td align="left">33.8</td><td align="left">68.0</td><td align="left">2298</td></tr>
+<tr><td align="left">Average</td><td align="left">120.0</td><td align="left">85.0</td><td align="left">102.5</td><td align="left">35.0</td><td align="left">72.0</td><td align="left">2550</td></tr>
+</table>
+
+<div class="center">(Taken from Weysse and Lutz.)</div>
+
+
+<p>In some experiments to determine the changes upon the
+blood pressure induced by hot and cold applications on and
+within the abdomen, Hammett, Tice and Larson found that
+heat applied to the outside of the abdomen raises the blood
+pressure. The application of cold produces no change. Either
+hot or cold saline introduced within the abdomen
+causes a fall in blood pressure.</p>
+
+<p><span class="pagenum"><a name="Page_105" id="Page_105">[105]</a></span>Experimentally, certain drugs such as adrenalin, barium
+chloride, nicotine, digitalis, strophanthus and the infundibular
+portion of the pituitary body known as pituitrin raise
+the maximum pressure. In the clinic it is difficult to conclude
+always whether the drug alone is responsible for rise
+in maximum pressure. Adrenalin given intravenously will
+raise the pressure. So will digitalis and strophanthus. I
+have watched the maximum pressure rise within three minutes
+following an intravenous injection of gr. <sup>1</sup>&frasl;<sub>100</sub> (0.0006
+gm.) strophanthin 20 mm. of Hg: I have seen the subcutaneous
+injection of 10 minims of adrenalin repeated several
+times daily for six months fail to have the least effect
+on the blood pressure picture.</p>
+
+<p>Elevation of the foot of the bed about nine inches proved
+so efficacious in steadying failing hearts in acute infectious
+diseases, particularly typhoid, that a study was made of
+the effect upon blood pressure. Many observations were
+made, but no instrumental proof of rise in blood pressure
+could be adduced.</p>
+
+<p>Exercise always raises blood pressure, the maximum
+much more than the minimum. In athletes the minimum
+pressure may actually fall, the maximum rise so that a
+greater volume output results from the greater pulse pressure.</p>
+
+<p>Shock and hemorrhage lower it. Hemorrhage lowers
+also the pulse pressure, and it may be possible to prognosticate
+internal hemorrhage by frequent estimations of the
+systolic and diastolic pressures (Wiggers). Compression
+of the superior mesenteric artery or the celiac axis in dogs
+raises the blood pressure measured in the carotid artery
+for a period of at least an hour. This seems to be dependent
+on purely mechanical causes, and is not a reflex vasomotor
+phenomenon. (Longcope and McClintock.)</p>
+
+<p>Experimentally blood pressure can be increased by direct
+compression of the brain as Cushing has shown. It was
+thought at one time that in man the same effect would result<span class="pagenum"><a name="Page_106" id="Page_106">[106]</a></span>
+from tumor of the brain or especially from subdural
+or extradural hemorrhage following head injuries. This,
+however, is not the case. No information of great value
+can be obtained by the measurement of blood pressure in
+these states. We do know that too high and too prolonged
+compression of the medulla brings about exhaustion of the
+cardiac center accompanied with rapid pulse, low pressure
+and eventual death.</p>
+
+
+<h4>Hypertension</h4>
+
+<p>All the conflict during the past few years over the subject
+of blood pressure has revolved around this much overworked
+word. Hypertension means high pressure, and yet
+it carries with it a suggestion of high pressure which is
+harmful to the individual. As a matter of fact hypertension
+is a compensatory process, it is often a saving process
+in spite of the fact that it carries possibilities of harm in
+its possessor. It has been made a fetish, a god to fall down
+before and worship and it has been the means of holding a
+torch of fear over a patient which has not been lost on the
+charlatans. Popularization of blood pressure has brought
+its crop of evils, no one of which has been as fruitful in
+dollars to unprincipled quacks as hypertension.</p>
+
+<p>Hypertension is the expression on the part of the circulation
+to meet new conditions in the tissues so that all tissues
+will be nourished and all will be enabled to function.
+Looked at from that point of view it is a conservative process
+and in many cases it is. It is not an average normal
+state, but it is normal state for the man who has it in
+chronic form. Hypertension should be viewed rationally
+and its proper place in the whole make-up of the patient determined.
+Hypertension is a relative term. What might
+be high pressure in a man of sedentary habits who reaches
+the age of fifty, might not be high pressure in a full blooded
+formerly athletic man of the same age. Temporary hypertension
+due to excitement, exercise, etc., must be kept in<span class="pagenum"><a name="Page_107" id="Page_107">[107]</a></span>
+mind. It is not intended to convey the impression that
+hypertension is of no moment. It is a matter for investigation,
+but not a matter to worship as the all-in-all.</p>
+
+<p>Hypertension is, after all, a physiologic response on the
+part of the organism in order to maintain the circulation in
+equilibrium in the face of conditions which tend to produce
+vasoconstriction in large areas and, therefore tend to deprive
+these areas of blood. That there must be some substance
+in the blood stream which causes this constriction
+seems certain. What it is, is not at present known. Recently,
+Voegtlin and Macht<a name="FNanchor_7_7" id="FNanchor_7_7"></a><a href="#Footnote_7_7" class="fnanchor">[7]</a> have isolated a crystalline substance
+from the blood of man and other mammals which
+they regard as a lipoid and closely related to cholesterin.
+This substance was recovered by them from the cortex of
+the adrenal gland. This becomes of added interest in the
+light of observations made by Gubar (quoted by Voegtlin
+and Macht). He noted "that the vasoconstricting properties
+of blood serum vary in different pathologic conditions,
+being increased in nephritis, for instance, and diminished
+in others." In some experiments made in the summer of
+1913, we found there was no marked difference in the anaphylactic
+shock produced in half-grown rabbits by the injection
+of normal and uremic blood serum. As lipoids do
+not cause anaphylaxis, there should be no difference in the
+reaction of normal and uremic sera unless in one there was
+some form of protein not in the other. This does not seem
+to be the case. The presence of something in the circulation,
+therefore, produces constriction of vessels. This calls
+for more force in contraction on the part of the heart. This
+substance may be of lipoid nature. The continued presence
+of this hypothetical substance naturally would lead to hypertrophy
+of the heart.</p>
+
+<p>What makes hypertension of significance is not the hypertension
+itself, but the fact that it is the expression of<span class="pagenum"><a name="Page_108" id="Page_108">[108]</a></span>
+processes going on in the body which demand exhaustive
+investigation. To attach a blood pressure cuff to the arm,
+find the pressure, and diagnose hypertension is like putting
+a thermometer under the tongue, noting a rise in the mercury,
+and diagnosing fever. What causes the hypertension?
+Can the causes be removed? Those are the really
+vital questions after the symptom hypertension has been
+discovered.</p>
+
+<p>All states of hypertension are accompanied by more or
+less increase of pulse pressure. In other words the systolic
+pressure is always increased to greater degree than the diastolic
+pressure. In studies carried out in the wards and
+Pathological Laboratory of the Milwaukee County Hospital,
+Milwaukee, we found that in all of the cases of chronic
+high blood pressure with resulting high pulse pressure four
+correlated factors were found. If any one of these factors
+is present, the other three are found.</p>
+
+<p>1. In all high pulse pressure cases there is increase in the
+size of the cavity of the left ventricle. The ventricle actually
+contains more blood when it is full, and throws out,
+therefore, more blood at each systole. The actual volume
+output is greater per unit of time. Such hearts always
+show increase in thickness of the ventricular wall. I quite
+agree with Stone,<a name="FNanchor_8_8" id="FNanchor_8_8"></a><a href="#Footnote_8_8" class="fnanchor">[8]</a> who says, "It is merely to be emphasized
+that when the pulse pressure persistently equals the
+diastolic pressure (high pressure pulse, in other words)
+with a resulting 50 per cent, <i>overload</i>, which means the expenditure
+of double the normal amount of kinetic energy on
+the part of the heart muscle, cardiac hypertrophy has occurred."
+They are found in aortic insufficiency, in chronic
+nephritis, in the diffuse fibrous type of arteriosclerosis, and
+in some cases of exophthalmic goiter. Such a condition
+occurs temporarily after exercise.</p>
+<p><span class="pagenum"><a name="Page_109" id="Page_109">[109]</a></span></p>
+<p>2. In all high pulse pressure cases there is actual permanent
+increase in diameter of the arch of the aorta. This
+is a compensating process to accommodate the increased
+charge from the left ventricle. Smith and Kilgore<a name="FNanchor_9_9" id="FNanchor_9_9"></a><a href="#Footnote_9_9" class="fnanchor">[9]</a> have
+shown this to be true in cases of chronic nephritis with hypertension.
+Their research confirms my own observations.
+They found dilatation of the arch in (1) syphilis (that is,
+aortitis); (2) age over 50 (that is, probable factor of arteriosclerosis);
+(3) other serious cardiac enlargement, and
+(4) hypertension (with more or less hypertrophy, as in
+chronic nephritis).</p>
+
+<p>In ten cases showing arches at the upper limit of normal
+(that is, 6 cm. in diameter) and hypertrophy of the heart,
+three were chronic mitral endocarditis; one was chronic
+aortic endocarditis; three were chronic mitral and aortic
+endocarditis, and there was one each of hyperthyroidism,
+pericarditis and adherent pericardium.</p>
+
+<p>In fourteen cases of hypertension (highest systolic 270
+mm., average systolic, 215 mm.), all showed cardiac hypertrophy.
+"All but three of these cases had great vessels
+whose transverse diameters measured over the normal
+limit of 6 cm., and in one of those measuring 6 cm. the
+Roentgen-ray diagnosis was 'slight dilatation' of the
+arch." Smith and Kilgore are at a loss to explain the three
+exceptions. They did not give diastolic pressures, so pulse
+pressures are not known. Possibly the three exceptions
+were cases of high diastolic pressure in which the pulse
+pressure possible was not over 60 mm. Such cases might
+show "slight dilatation of the arch," but not marked dilatation,
+such as was found in the other, evidently high pulse
+pressure cases.</p>
+
+<p>We have found that only the high pulse pressure cases
+show dilatation of the arch. Certain high tension cases
+which have had a very high diastolic pressure do not reveal
+any accurately measurable dilatation of the aortic<span class="pagenum"><a name="Page_110" id="Page_110">[110]</a></span>
+arch. An empty aorta after death is quite different from a
+functionating aorta during life. Hence the dilatation
+which is found postmortem must have been considerable
+during life. And conversely, a dilatation which was present
+during life might not be looked on as such after death.</p>
+
+<p>3. In all high pulse pressure cases one will find on careful
+auscultation over the manubrium, particularly its lower
+half, breath sounds which vary from bronchial to intensely
+tubular. At times the percussion note will be slightly impaired,
+as McCrae<a name="FNanchor_10_10" id="FNanchor_10_10"></a><a href="#Footnote_10_10" class="fnanchor">[10]</a> has shown in dilatation of the arch of
+the aorta. This auscultatory sign is evidence of some more
+or less solid body in the anterior mediastinum which is
+lying on the trachea and permits the normal tubular breathing
+in the trachea to be audible over the upper part of the
+sternum. It is found in cases of dilated aortic arch. Fluoroscopic
+examination has confirmed the findings on auscultation.</p>
+
+<p>4. In all high pulse pressure cases, in which the pulse
+pressure is over 70 mm. of mercury, there is increase in
+the size of all large distributing arteries, carotids, brachials,
+femorals, renals, celiac axis, etc., with fibrous changes in
+the media, loss of some of the elasticity, and in the palpable
+superficial arteries, increase in size of the pulse wave.</p>
+
+<p>Increased pulse pressure means increased volume output,
+but does not always mean increased velocity. The proper
+distribution of blood to the various organs of the body is
+regulated by the vasomotor system acting on the small arteries
+which contain considerable unstriated muscle. In
+order that there may be enough blood at all times and under
+varying conditions of rest and function, there must be a
+proper supply coming through the distributing vessels, the
+large arteries, those containing much elastic tissue, and
+only a very small amount of unstriated muscle tissue or
+none whatever. Fibrous sclerosis of these vessels causes
+them to become enlarged and tortuous and to lose much<span class="pagenum"><a name="Page_111" id="Page_111">[111]</a></span>
+of their elasticity, which is essential for the even distribution
+of blood. A greater blood volume is therefore necessary
+in order that the organs may receive their quota of
+blood. A force which is sufficient to send blood through
+elastic normal distributing tubes becomes totally insufficient
+to send the same amount of blood through tortuous and
+more or less inelastic tubes. As a compensatory process
+the pulse pressure increases. For this to increase, the left
+ventricular cavity dilates, the arch dilates, and as a greater
+force must be exerted to keep the increased mass in motion,
+the heart responds by hypertrophy of its left ventricle and
+becomes itself the subject of fibrous changes in the myocardium.
+The mass movement of blood is therefore greater
+in high pulse pressure cases than in cases of normal pulse
+pressure.</p>
+
+<p>In cases of chronic interstitial nephritis&mdash;contracted
+granular kidney&mdash;it may well be that the sclerosis of the
+arteries is a secondary process caused, as Adami thinks,
+by the hypertension itself. In aortic insufficiency the situation
+is somewhat different. The high pulse pressure is due
+to a very low diastolic pressure, for in my experience with
+uncomplicated aortic insufficiency the systolic pressure is,
+as a rule, not much increased above the normal for the individual's
+age. Here peripheral resistance is so low that
+a capillary pulse is common. The volume output per unit
+of time is greatly increased, the arch of the aorta is dilated,
+and the pulse is large. The fact that a large part of the
+blood regurgitates during diastole back into the ventricle,
+and the fact that the diastolic pressure is low means that
+there is no increased resistance to overcome, and the systolic
+pressure is not raised.</p>
+
+<p>Stone<a name="FNanchor_11_11" id="FNanchor_11_11"></a><a href="#Footnote_11_11" class="fnanchor">[11]</a> has divided the cases of hypertension into the cerebral
+and cardiac types. He finds that there is a difference
+in prognosis and in the mode of death in the two groups.
+He has further attempted to judge of the work placed upon<span class="pagenum"><a name="Page_112" id="Page_112">[112]</a></span>
+the heart by calculating what he calls the heart load or pressure-ratio.
+For example, he takes a normal pressure at
+120-80-40. The relation between 80 and 40 is &frac12; or 50 per
+cent. That he considers normal. When the heart load increases
+so that the pulse pressure equals or exceeds the
+diastolic pressure, the heart load is 100 per cent or more,
+he considers the danger of myocardial exhaustion graver
+than when the heart load is normal or less than 50 per cent.</p>
+
+<p>It is his opinion, in which I heartily concur, "that an
+individual with a systolic pressure of 200 and a diastolic
+pressure of 140, is in greater danger of cerebral death than
+an individual with a systolic pressure of 200 and a diastolic
+pressure of 100." He is "likewise certain that the individual
+with a systolic pressure of 200 and a diastolic of
+90 to 100 is in greater danger of a cardiac death. It is
+apparently the constant high diastolic pressure rather than
+the intermittently high systolic pressure which predisposes
+to cerebral accident."</p>
+
+<p>I have not been able to confirm all of Stone's conclusions.
+His contention holds good for some cases, but not, in my
+experience, for the great majority of the hypertension cases.
+I feel that in the classification of the chronic high pressure
+case we can go one step farther and split his first group
+into two usually differentiable groups. Syphilis is not an
+etiological factor in any of these groups. It is not considered
+that these groups are absolutely distinct and can always
+be rigidly separated. There are variations and combinations
+which render an exact separation impossible.
+But bearing this in mind the following classification is proposed
+as a working classification.</p>
+
+<p>Group A. Chronic nephritis.</p>
+
+<p>Group B. Essential hypertension.</p>
+
+<p>Group C. Arteriosclerotic hypertension.</p>
+
+<p>Group A. <i>Chronic Nephritis.</i> These are the cases with
+a high-pressure picture, that is to say, high systolic (200+)
+and high diastolic (120-140+). The pulse pressure is much<span class="pagenum"><a name="Page_113" id="Page_113">[113]</a></span>
+increased. The palpable arteries are hard and fibrous.
+There is puffiness of the under eyelids, which is more pronounced
+in the morning on arising. Polyuria with low
+specific gravity and nycturia are present. There are almost
+constant traces of albumin in the urine, with hyaline and
+finely granular casts.</p>
+
+<p>Functionally these kidneys are much under normal. The
+functional capacity determined by Mosenthal's modification
+of the Schlayer-Hedinger method shows a marked inability
+to concentrate salts and nitrogen. The phthalein output
+is below normal. As the case advances the phthalein output
+becomes less and less, until a period is reached when there
+are only traces or complete suppression at the end of a two-hour
+period. Such patients may live for ten weeks (one of
+our cases) or longer, all the time showing mild uremic
+symptoms, and suddenly pass into coma and die.</p>
+
+<p>The natural end of patients in this group is either uremia
+or cardiac decompensation (so-called cardiorenal disease).
+Cerebral accidents may happen to a small number. It is
+only to this group, in my opinion, that the term cardiorenal
+disease should be applied. Formerly I believed that all high
+systolic pressure cases were cases of chronic nephritis of
+some definite degree. From the purely pathologic standpoint
+that is true, but from the important, functional standpoint
+it is far from being the true state of the cases.</p>
+
+<p>In this group there is marked hypertrophy and moderate
+dilatation of the left ventricle with dilatation and nodular
+sclerosis of the aorta. The kidneys are firm, red, small,
+coarsely granular, the cortex much reduced, the capsule
+adherent. Cysts are common. It is the familiar primary
+contracted kidney. Mallory calls this capsular-glomerulonephritis.
+The etiology is obscure. Often no cause can be
+found. Again, there is a history of some kidney involvement
+following one of the acute infectious diseases, or it
+may follow the nephritis of pregnancy. Usually, however,<span class="pagenum"><a name="Page_114" id="Page_114">[114]</a></span>
+these cases fall into the group of secondary contracted kidneys,
+chronic parenchymatous nephritis.</p>
+
+<blockquote><p>Illustrative Case.&mdash;R. Z., a woman, aged thirty-six years, was seen July 26,
+1916, in coma. There was a history of typhoid fever at nineteen years, but no
+other disease. She had had nine full-term pregnancies, the last one thirteen
+months previously. For a week before the onset of the present illness she had
+complained of severe headaches and dizziness. There were no heart symptoms.
+For the past year she has had nycturia. Physical examination revealed tubular
+breathing beneath the manubrium, a few rales in the chest, an enlarged heart
+(left side), with a systolic murmur over the aortic area. Blood pressure was
+178-125-53, the pulse rate 96, leucocytes 27,250. Venesection of 500 c.c. of
+blood and intravenous injections of 500 c.c. of 5 per cent NaHCO<sub>3</sub> in normal
+saline were employed. Lumbar puncture withdrew 60 c.c. of clear fluid under
+pressure with 6 cells per cubic millimeter. The eye grounds showed distinct
+haziness of the disks and dilatation of the veins. Blood pressure after venesection
+was 164-122-42, pulse 76, but in a few days rose to 222-142-80, pulse 70.
+A second venesection of 400 c.c. and proctoclysis of 1000 c.c. saline solution
+was tried. The blood-pressure now was 198-140-58. The pH of the blood was
+7.6, the alkaline reserve was 35 volume per cent (van Slyke), and the CO<sub>2</sub>
+tension of the alveolar air (Marriott) was 25 mm. The phthalein on the day
+following the second venesection was 45 per cent in two hours. The urine
+at first showed 500 c.c. in twenty-four hours, specific gravity 1016, albumin
+and casts. Later she passed 1300 to 1600 c.c. with specific gravity around
+1010. The blood-pressure fluctuated considerably, reaching as low as 138-98-40,
+pulse 88. She was discharged improved September 10, 1916. She had
+constant headache but managed to keep up. In June, 1917, she suddenly
+died in an uremic coma.</p></blockquote>
+
+<p>Group B. This one might designate as the hereditary
+type, although there is not always a history in the antecedent.
+This group includes the robust, florid, exuberantly
+healthy people. They often are heard to boast that they
+have never had a doctor in their lives. They are usually
+thick-set or very large, fleshy people. The pressure picture
+is exceedingly high. The pulse pressure is moderately
+increased. The arteries are rather large, fibrous, and often
+quite tortuous, although this is not always the case. Some
+persons have hard, small, fibrous arteries. There is no
+puffiness beneath the eyes, no polyuria, and no nycturia as
+a rule. The urine is of normal amount, color, and specific
+gravity. Albumin is only rarely found and then in traces,
+but careful search of a centrifuged specimen invariably reveals<span class="pagenum"><a name="Page_115" id="Page_115">[115]</a></span>
+a few hyaline casts. The phthalein excretion is normal
+or only slightly reduced. The kidneys excrete salt and
+nitrogen normally. It is in this group that apoplexy is
+found most frequently. The rupture of the vessel occurs
+when the victim is in perfect health, often without any
+warning. Occasionally when such a case recovers sufficiently
+to be around, cardiac decompensation sets in later
+and he dies then of the cardiac complications.</p>
+
+<p>Pathologically the hearts of such persons are found to
+have the most enormous hypertrophy of the wall of the left
+ventricle. The cavity is somewhat enlarged, as is always
+the case when the pulse-pressure is increased, but the size
+of the cavity is not the striking feature. The aorta is
+fibrous, thick walled, and the arch is slightly dilated. There
+are patches of arteriosclerosis. One such case seen only
+at autopsy had a rupture of the aorta just above the sinus
+of Valsalva and died of hemopericardium. The kidneys
+are of normal size, dark red, firm, the capsule strips readily,
+the surface is smooth or finely granular, the cortex is not
+decreased. The pyramids are congested and red streaks extend
+into the cortex. Microscopically the capsules of the
+glomeruli are a trifle thickened; a few show hyaline
+changes. There is rather diffuse, mild, round-cell infiltration
+between the tubules. The tubular epithelium shows little
+or no demonstrable changes. The arterioles are generally
+the seat of a moderate thickening of the intima and media,
+but it is not usual to find obliterating endarteritis.
+There is evidently a diffuse fibrous change which has not
+affected either the tubules or glomeruli to any great extent.</p>
+
+<blockquote><p>Illustrative Case.&mdash;L. C., a man, aged fifty-six years, stonemason by trade,
+is a stocky, thick-necked individual. He had never been ill in his life until
+a year ago, when he fell from his chair unconscious. He had a right-sided
+hemiplegia which has cleared up so completely that except for a very slight
+drag to his foot he walks perfectly well. He came in complaining of shortness
+of breath and cough. There was no swelling of the feet. Here evidently
+was left-heart decompensation. Examination showed the blood pressure
+to be 240-130-110, pulse irregular, 104 to the minute. There were cyanosis
+and rales throughout both chests. The urine was normal in color, specific<span class="pagenum"><a name="Page_116" id="Page_116">[116]</a></span>
+gravity 1025, small amount of albumin, few casts, hyaline and granular.
+The phthalein elimination was 65 per cent in two hours. Under rest, purgatives,
+and digitalis he was much improved. He has since had two other
+apoplectic strokes, the last of which was fatal.</p></blockquote>
+
+<p>When these patients are seen with acute cardiac decompensation,
+there are, of course, much albumin and many
+casts in the urine, and the phthalein output is, for the time
+being, decreased.</p>
+
+<p>Group C. This might be called the arteriosclerotic high-tension
+group (Stone's cardiac group). The cases are usually
+over fifty years old. They are men and women who
+have lived high and thought hard. Often they have had
+periods of great mental strain. Many men in this group
+were athletes in their young manhood. Many have been
+fairly heavy drinkers, although never drinking to excess.
+They are usually well nourished and inclined to stoutness.
+The pressure picture is high systolic with normal or only
+slightly increased diastolic and large pulse pressure. The
+arteries are large, full, fibrous, usually tortuous. The heart
+is very large, the apex far down and out. There is no polyuria;
+nycturia is uncommon, quite the exception. The urine
+is normal in color, amount, and specific gravity. Albumin
+is only rarely found and hyaline casts are not invariably
+present. The phthalein excretion is quite normal and the
+excretions of salt and nitrogen are also normal. The terminal
+condition in most of the patients in this group is cardiac
+decompensation. They may have several attacks from
+which they recover, but after every attack the succeeding
+one is produced by less exertion than the preceding one, and
+it becomes more and more difficult to control attacks.
+Eventually the patients become bed- or chair-ridden, and
+finally die of acute dilatation of the heart.</p>
+
+<p>Occasionally patients in this group may have a cerebral
+attack, but in my experience this is uncommon. Pathologically
+the heart is large, at times true <i>cor bovinum</i>, dilated
+and hypertrophied. The cavity of the left ventricle is much
+dilated. The aorta is dilated and sclerosed.</p>
+
+<p><span class="pagenum"><a name="Page_117" id="Page_117">[117]</a></span>The kidneys are increased in size, are firm, dark red
+in color, with fatty streaks in the cortex. The capsule strips
+readily and the cortex is normal in thickness or only
+slightly increased. The organ offers some resistance to the
+knife. The microscope shows small areas scattered
+throughout where the glomeruli are hyalinized, the stroma
+full of small round cells, the tubules dilated, and the cells
+are almost bare of protoplasm. Naturally the tubules are
+full of granular cast material. Also the arterioles show
+extensive intimal thickening, fibrous in character, with occasional
+obliterating endarteritis. One gets the impression
+that the small sclerotic lesions are the result of anemia and
+gradual replacement of scattered glomeruli by fibrous tissue.
+For the most part the kidney, except for the chronic
+passive congestion, appears quite normal. One can readily
+understand that in such a kidney function could not have
+been much interfered with.</p>
+
+<blockquote><p>Illustrative Case.&mdash;C. K., an active, stout, business man, aged fifty-six
+years, consulted me on account of shortness of breath and swelling of the feet
+in May, 1915. He had just returned from a hospital in another city, where
+he had gone with what was apparently cardiac decompensation. In his early
+manhood he had been a gymnast and a prize winner. He has worked hard,
+often given way to violent paroxysms of temper, has eaten heavily but drunk
+very moderately. The heart was greatly enlarged, the arch of the aorta
+dilated, a mitral murmur was audible at the apex. The radials and temporals
+were large, tortuous, and fibrous. The blood pressure picture ranged around
+180-90-90. He was easily made dyspneic and had a tendency to swelling of
+the lower legs. The urine was acid, of normal specific gravity, normal in
+amount, normal phthalein, normal concentration of salt and nitrogen, contained
+albumin only when he was suffering from decompensation of the heart.
+Casts were always found. He finally died, after sixteen months, with all
+the symptoms of chronic myocardial insufficiency. The heart was enormous,
+a true <i>cor bovinum</i>. The kidneys were typical of this condition, possibly
+somewhat larger than usual.</p></blockquote>
+
+
+<h4>Hypotension</h4>
+
+<p>When the pressure is constantly below the normal, it is
+called hypotension. This may be transient&mdash;as in fainting&mdash;it
+may be a normal state of the individual, it occurs in<span class="pagenum"><a name="Page_118" id="Page_118">[118]</a></span>
+most fevers and in a great variety of diseases, including
+anemias.</p>
+
+<p>In arteriosclerosis, especially the diffuse (senile) type,
+the blood pressure is invariably low, and may be spoken of
+as hypotension. The heart in such a case is small, the
+muscle is flabby, there is brown atrophy of the fibers, and
+some replacement of the muscle cells by connective tissue.
+The same causes which have produced general arteriosclerosis
+have also produced sclerosis of the coronary arteries,
+and probably the lessened blood supply accounts for much
+of the atrophy of the heart muscle.</p>
+
+<p>In typhoid fever the maximum blood pressure during
+beginning convalescence may be as low as 65 mm. Hg. I
+have frequently seen hypotension of 80 mm. This is common.</p>
+
+<p>Meningitis is the only acute infectious disease in which
+the blood pressure is more often high than low. This is
+accounted for by the increased intracranial tension.</p>
+
+<p>Following large hemorrhages the blood pressure is reduced.
+In venesection the withdrawal of blood may not
+affect the blood pressure. The procedure is done to relieve
+overdistension of the heart.</p>
+
+<p>In pleurisy with effusion and in pericarditis with effusion
+there is hypotension.</p>
+
+<p>Collapse, whether from poisoning by drugs or as the result
+of dysentery, cholera, or profuse vomiting from whatever
+cause, reduces the blood pressure.</p>
+
+<p>In cachectic states, such as cancer, the blood pressure is
+low. General wasting of the whole musculature includes
+that of the heart and the heart muscle shows the condition
+known as "brown atrophy."</p>
+
+<p>A most interesting and important condition in which
+hypotension occurs is pulmonary tuberculosis. Haven
+Emerson has recently gone over the whole subject in a careful
+piece of work and his summary is as follows:</p>
+
+<p>"Hypotension or subnormal blood pressure is universally<span class="pagenum"><a name="Page_119" id="Page_119">[119]</a></span>
+found in advanced pulmonary tuberculosis, in which
+condition emaciation may play a part in its causation.
+Hypotension is found in almost all cases of moderately advanced
+tuberculosis, or in early cases in which the toxemia
+is marked except when arteriosclerosis, the so-called arthritic
+or gouty diathesis, chronic nephritis, or diabetes
+complicate the tuberculosis and bring about a normal pressure
+or a hypertension. Occasionally the period just preceding
+a hemoptysis or during a hemoptysis may show hypertension
+in a patient whose usual condition is that of
+hypotension.</p>
+
+<p>"Hypotension has been found by so many observers in
+early, doubtful or suspected cases with or before physical
+signs of the disease in the lungs, and is considered by competent
+clinicians so useful a differential sign between various
+conditions and tuberculosis, that it should be sought for
+as carefully as it is the custom at present to search for
+pulmonary signs.</p>
+
+<p>"Hypotension when found persistently in individuals or
+families or classes living under certain unhygienic conditions
+should put us on our guard against at least a predisposition
+to tuberculosis. Most unhygienic conditions,
+overwork, undernourishment and insufficient air, are of
+themselves causes of a diminished resistance, and it seems
+likely that a failure of normal cardiovascular response to
+exercise or change of position may be found to indicate this
+stage of susceptibility, especially to tuberculous infection.</p>
+
+<p>"... Hypotension, when it is present in tuberculosis, increases
+with an extension of the process. Recovery from
+hypotension accompanies arrest or improvement. Return
+to normal pressure is commonly found in those who are
+cured. Continuation of hypotension seems never to accompany
+improvement. Prognosis can as safely be based on
+the alteration in the blood pressure as on changes in the
+pulse or temperature...."</p>
+
+<p>There are a few drugs which lower the blood pressure,<span class="pagenum"><a name="Page_120" id="Page_120">[120]</a></span>
+but, as a rule, their effects are more or less transitory. We
+know of no drug, unless it be iodide of potassium, which has
+the property of causing changes in the blood (decrease in
+viscosity?), which tends to reduce the blood pressure when
+it is excessive. This drug fails us many times.</p>
+
+
+<div class="center">SOME DRUGS WHICH INFLUENCE THE BLOOD PRESSURE</div>
+
+<p>
+<b>Pressure Raisers</b><br />
+<br />
+Adrenalin, when injected directly<br />
+into a vein or deep into the muscles.<br />
+The action is transitory.<br />
+<br />
+Caffeine, preferably in the form<br />
+of caffeine-sodium-benzoate. A good<br />
+drug.<br />
+<br />
+Strychnine, which does not act directly<br />
+but seemingly through the<br />
+higher centers.<br />
+<br />
+Ergot, somewhat uncertain.<br />
+<br />
+Nicotine, not used therapeutically.<br />
+<br />
+Camphor, used in sterile olive oil<br />
+and injected deeply into the muscles.<br />
+<br />
+Digitalis, when the cardiac tone is<br />
+low and decompensation is present.<br />
+Its action is prolonged but slow. Injections<br />
+of the infundibular portion<br />
+of the pituitary body. Not in use<br />
+clinically.<br />
+<br />
+<br />
+<b>Pressure Depressors</b><br />
+<br />
+Nitroglycerine and amyl nitrite,<br />
+action transitory but rapid.<br />
+<br />
+Sodium nitrite and erythrol tetranitrate.<br />
+Action somewhat more prolonged.<br />
+<br />
+Aconite, veratrum viride, chloral,<br />
+etc. These depress the heart.<br />
+<br />
+Purgatives, drastic and hydragogue.<br />
+<br />
+Potassium and sodium iodide may<br />
+lower blood pressure. When they do,<br />
+the action is prolonged.<br />
+<br />
+Diuretin and theocin-sodium-acetate.<br />
+</p>
+
+
+<h4>Venous Pressure</h4>
+
+<p>Comparatively little work has been done upon the determination
+of the pressure in the veins in man. It is conceivable
+that this procedure may, at times, be of great
+value. A number of attempts have been made to measure
+the venous pressure by compressing the arm veins and noting
+on a manometer the force necessary to obliterate the
+vein. As the pressure is so slight, water is used instead
+of mercury, and readings have been given in centimeters
+of water.</p>
+
+<div class="figcenter" style="width: 330px;">
+
+<a name="Venous_blood_pressure_instrument" id="Venous_blood_pressure_instrument"></a>
+
+
+<img src="images/fig_033.png" width="330" height="500" alt="Fig. 33.&mdash;Apparatus for estimating the venous blood pressure in man, devised by
+Drs. Hooker and Eyster. The small figure is the detail of the box B. See explanation
+in text." title="Fig. 33.&mdash;Apparatus for estimating the venous blood pressure in man, devised by
+Drs. Hooker and Eyster. The small figure is the detail of the box B. See explanation
+in text." />
+<span class="caption">Fig. 33.&mdash;Apparatus for estimating the venous blood pressure in man, devised by
+Drs. Hooker and Eyster. The small figure is the detail of the box B. See explanation
+in text.</span>
+</div>
+
+<p>In the apparatus shown in the figure (Fig. 33), Drs.
+Hooker and Eyster succeeded in making estimations of the
+venous pressure. The box <i>B</i> is held in position by the tapes
+<i>A</i>, so that the vein is visible through the rectangular opening
+in the thin rubber covering the bottom. The box is connected
+with the water manometer <i>G</i>, by a rubber tube,
+from which a T-tube enters the rubber bulb <i>E</i>. When the
+bulb <i>E</i> is compressed between the plates <i>D</i>, by the coarse<span class="pagenum"><a name="Page_121" id="Page_121">[121]</a></span>
+thumbscrew <i>C</i>, air is forced into the box <i>B</i>, exerting a pressure
+on the vein lying exposed beneath. This pressure is
+transmitted directly to the manometer <b>G</b>, and may be read
+off in centimeters of water on the accompanying scale. The
+veins of the back of the hand are used and there must be no
+obstruction between them and the heart. The rubber-covered
+box is accurately and lightly fitted over a vein and
+pressure made until it is obliterated. By measuring the
+distance above or below the heart level that the hand was
+when the observation was made, and subtracting or adding<span class="pagenum"><a name="Page_122" id="Page_122">[122]</a></span>
+these figures to the manometer reading, we obtain the
+venous pressure at the heart level.</p>
+
+<p>Eyster has modified this instrument so that it is now
+much simpler to operate. He uses a small glass cup with a
+flaring edge and a diameter of about 2 cm. This is sealed
+to the skin directly over a vein on the back of the hand by
+means of collodion. The stem of the cup has a rubber tube
+leading to a small hand bulb and to the manometer tube
+which contains colored water. Slight compression of the
+hand bulb obliterates the vein which can be seen through
+the glass cup. The pressure in centimeters of water is then
+read off. (Fig. 34.) The principle is the same as in the
+earlier instrument, but the application is easier.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="New_venous_pressure_instrument" id="New_venous_pressure_instrument"></a>
+
+
+<img src="images/fig_034.png" width="500" height="424" alt="Fig. 34.&mdash;New venous pressure instrument. (After Eyster.)" title="Fig. 34.&mdash;New venous pressure instrument. (After Eyster.)" />
+<span class="caption">Fig. 34.&mdash;New venous pressure instrument. (After Eyster.)</span>
+</div>
+
+<p>Practically Hooker and Eyster found that the normal
+variation in healthy subjects was from 3 to 10 cm. of water.
+The pressure rose in cases of decompensated hearts with<span class="pagenum"><a name="Page_123" id="Page_123">[123]</a></span>
+dyspnea and venous stasis, and returned to normal with
+improvement in the condition of the patient. It might be
+possible with this instrument to foretell an oncoming decompensation
+by the rise in venous pressure.</p>
+
+<p>The venous pressure may also be estimated roughly by
+slowly elevating the arm and noting the instant at which
+a particular vein collapses. By measuring the height of
+the vein above the heart some idea may be obtained of the
+pressure within the right auricle.</p>
+
+
+<h4>The Pulse</h4>
+
+<p>There is nothing characteristic about the pulse of a
+person suffering from arteriosclerosis, except it be the difference
+in the pulse of high tension and of low tension.
+The pulse of high tension has a gradual rise, a more or less
+rounded apex, and the dicrotic wave is slightly marked and
+occurs about half-way down on the descending limb. In
+arteriosclerosis with low tension the radial artery is usually
+so rigid that very little pulse wave can be obtained. The
+general form of a low tension pulse is a sharp upstroke, a
+pointed summit, and a secondary wave on the base line,
+which corresponds to the dicrotic wave. Such a pulse can
+be easily palpated, and is known as a dicrotic pulse. However,
+such a pulse can occur only when the artery still retains
+all or a large part of its elasticity; hence in arteriosclerotic
+low tension we would never see such a pulse as
+the typical dicrotic.</p>
+
+
+<h4>The Venous Pulse</h4>
+
+<p>It would carry us too far to discuss fully the character
+of the venous pulse, but a brief summary of the essential
+features of the normal venous pulse is presented. The
+venous pulse is a term used to express the tracing obtained
+from the internal or external jugular vein at the root of
+the neck. Normally a very characteristic curve is produced,
+which can be readily analyzed into a series of waves corresponding<span class="pagenum"><a name="Page_124" id="Page_124">[124]</a></span>
+to the fluctuations in the cardiac cycle. To understand
+these waves and their values, the accompanying
+figure is helpful. (Fig. 35.)</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Events_in_the_cardiac_cycle" id="Events_in_the_cardiac_cycle"></a>
+
+
+<img src="images/fig_035.png" width="500" height="459" alt="Fig. 35.&mdash;Semidiagrammatic representation of the events in the cardiac cycle: Jug.,
+pulse in the jugular vein; Aur., contraction of auricle; V. Pr., intraventricular pressure;
+Pap. M., contraction of the papillary muscles; Car., carotid pulse. Below are
+given the times of occurrence of the heart sounds and of the opening and closing of
+the heart valves. (After Hirschfelder.)" title="Fig. 35.&mdash;Semidiagrammatic representation of the events in the cardiac cycle.... (After Hirschfelder.)" />
+<span class="caption">Fig. 35.&mdash;Semidiagrammatic representation of the events in the cardiac cycle: Jug.,
+pulse in the jugular vein; Aur., contraction of auricle; V. Pr., intraventricular pressure;
+Pap. M., contraction of the papillary muscles; Car., carotid pulse. Below are
+given the times of occurrence of the heart sounds and of the opening and closing of
+the heart valves. (After Hirschfelder.)</span>
+</div>
+
+<p>Bachmann summarizes the normal waves in the venous
+pulse tracing as follows:</p>
+
+<p>"The physiological or so-called venous pulse consists of
+three positive and three negative waves, bearing a more or
+less definite relation to the events of the cardiac cycle, and
+having their origin in the various movements of the chambers
+and structures of the right heart. The first positive
+wave (<i>a</i>) is presystolic in time, and is due to the contraction
+of the auricle, causing a slowing of the venous current
+and producing a centrifugal wave through a sudden arrest
+of the inflowing blood. The second positive wave (<i>S</i>) is
+presystolic in time, and originates in the sudden projection<span class="pagenum"><a name="Page_125" id="Page_125">[125]</a></span>
+of the tricuspid valve into the cavity of the auricle during
+the quick, incipient rise in the intraventricular pressure
+occurring in the protosystolic period. The third positive
+wave (<i>v</i>) occurs toward the end of ventricular systole. It
+consists of two lesser waves separated by a shallow notch.
+The factors entering into its formation are the relaxation
+of the papillary muscle at a time when the intraventricular
+is still higher than the intraauricular pressure, resulting
+in an upward movement of the tricuspid leaflets and a return
+of the auriculoventricular septum to its position of
+rest.</p>
+
+<p><span class="pagenum"><a name="Page_126" id="Page_126">[126]</a></span>"The first negative wave (between positive wave <i>a</i> and
+<i>S</i>) is due to the relaxing auricle. The second negative
+wave (<i>Af</i>) occurs during the diastole of the auricle. It
+is due to the dilatation of its walls, to the displacement of
+the auriculoventricular septum toward the apex occurring
+at the time of ventricular systole, and to the pull of the
+papillary muscles on the tricuspid valve leaflets. The third
+negative wave (<i>Vf</i>) appears during ventricular diastole and
+in the common pause of the heart chambers. Its cause is
+found in the passage of the blood from the auricle into the
+ventricle. It is somewhat modified possibly by the continual
+ascent of the auriculoventricular septum and by a wave
+of stasis due to the accumulation of blood coming from the
+periphery." (Fig. 36.)</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Simultaneous_tracings_of_the_jugular_and_carotid_pulses" id="Simultaneous_tracings_of_the_jugular_and_carotid_pulses"></a>
+
+
+<img src="images/fig_036.png" width="500" height="295" alt="Fig. 36.&mdash;Simultaneous tracings of the jugular and carotid pulses showing normal waves
+in the venous pulse and relation to carotid pulse. (After Bachmann.)" title="Fig. 36.&mdash;Simultaneous tracings of the jugular and carotid pulses showing normal waves
+in the venous pulse and relation to carotid pulse. (After Bachmann.)" />
+<span class="caption">Fig. 36.&mdash;Simultaneous tracings of the jugular and carotid pulses showing normal waves
+in the venous pulse and relation to carotid pulse. (After Bachmann.)</span>
+</div>
+
+<p>Hirschfelder has described another wave which he calls
+the "h" wave, which is due to the floating up of the tricuspid
+valve by the blood in the ventricle before the complete
+filling of the ventricle following the auricular systole. (Fig.
+37.)</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Jugular_and_carotid_tracings" id="Jugular_and_carotid_tracings"></a>
+
+
+<img src="images/fig_037.png" width="500" height="169" alt="Fig. 37.&mdash;Jugular and carotid tracing from a normal individual with a well-marked
+third heart sound showing a large &quot;h&quot; and a smaller pre-auricular wave &quot;w.&quot; ? indicates
+a small wave in mid-diastole following the &quot;h&quot; wave, occasionally found though
+perhaps an artefact. (After Hirschfelder.)" title="Fig. 37.&mdash;Jugular and carotid tracing from a normal individual with a well-marked
+third heart sound.... (After Hirschfelder.)" />
+<span class="caption">Fig. 37.&mdash;Jugular and carotid tracing from a normal individual with a well-marked
+third heart sound showing a large &quot;h&quot; and a smaller pre-auricular wave &quot;w.&quot; ? indicates
+a small wave in mid-diastole following the &quot;h&quot; wave, occasionally found though
+perhaps an artefact. (After Hirschfelder.)</span>
+</div>
+
+<h4>The Electrocardiogram</h4>
+
+<p>In the past few years an immense amount of work has
+been done by numerous observers on the changes in the
+electrical potential of the various portions of the heart
+during contraction. The very elaborate and delicate electrocardiograph
+with the string galvanometer devised by
+Einthoven is used. It has been definitely determined that
+the impulse to cardiac contraction originates in the sinus
+node, a collection of differentiated nerve cells situated at
+the junction of the superior vena cava with the right auricle.
+From there the impulse travels in certain fibers in the interauricular
+wall, passes through another node, the auriculoventricular
+or Tawara node, situated in the auricular
+wall just above the auriculoventricular ring, thence via
+the Y-bundle, or bundle of His to the ventricles. This sequence<span class="pagenum"><a name="Page_127" id="Page_127">[127]</a></span>
+is orderly, regular, and normally invariable. (Fig.
+38.)</p>
+
+<div class="figcenter" style="width: 473px;">
+
+<a name="Right_side_of_the_heart_showing_distribution_of_the_two_vagus_nerves" id="Right_side_of_the_heart_showing_distribution_of_the_two_vagus_nerves"></a>
+
+
+<img src="images/fig_038.png" width="473" height="500" alt="Fig. 38.&mdash;Right side of the heart showing diagrammatically the distribution of the
+two vagus nerves to different parts of the viscus....(Hare&#39;s Practice of Medicine.)" title="Fig. 38.&mdash;Right side of the heart showing diagrammatically the distribution of the
+two vagus nerves to different parts of the viscus.... (Hare&#39;s Practice of Medicine.)" />
+<span class="caption">Fig. 38.&mdash;Right side of the heart showing diagrammatically the distribution of the
+two vagus nerves to different parts of the viscus. The impulse to contraction originates
+at the sino-auricular node and passes over the wall of the auricle to Tawara&#39;s node, and
+thence over His&#39; bundle across the auriculoventricular septum to be distributed throughout
+the ventricular wall. If the upper, sino-auricular, node is damaged, or if its impulses
+fail to get across the wall of the auricle, Tawara&#39;s node acts in its place to start
+off the ventricle. If a lesion at the base of the mesial segment of the tricuspid valve
+damages His&#39; bundle, so that Tawara&#39;s node is cut off from the ventricle, then the ventricle
+may originate its own impulses to contraction. (Hare&#39;s Practice of Medicine.)</span>
+</div>
+
+<p>The sino-auricular (s-a) node is the most irritable portion
+of the heart, it is endowed with the greatest amount<span class="pagenum"><a name="Page_129" id="Page_129">[129]</a></span><span class="pagenum"><a name="Page_128" id="Page_128"></a></span>
+of rhythmicity as well. It is under the control of the vagus
+nerve. Its inherent rate of rhythmicity is probably more
+rapid than the usual numbers of impulses per minute, but
+it is inhibited by the vagus. Paralysis of the vagus endings
+increases the rate of impulse formation and therefore the
+rate of the heart.</p>
+
+<p>The electrocardiogram is a graphic representation on a
+photographic film or sensitive bromide paper of the changes
+of electrical potential during muscular activity. The lines
+are made by the highly magnified string of the galvanometer
+as it moves across the slit in the photographic apparatus
+in response to the induction currents set up in the
+heart magnified by the special galvanometer.</p>
+
+<p>The record is made in three so-called Leads.</p>
+
+<div class="center">
+Lead I<br />
+<br />
+The electrodes are attached to right arm and left arm.<br />
+<br />
+Lead II<br />
+<br />
+The electrodes are attached to right arm and left leg.<br />
+<br />
+Lead III<br />
+<br />
+The electrodes are attached to left arm and left leg.<br />
+</div>
+
+<p>A series of regular figures is normally obtained in which
+are depressions and elevations and regular spacing of these
+elevations and depressions. The waves so-called have been
+arbitrarily designated <i>P</i>, <i>Q</i>, <i>R</i>, <i>S</i>, <i>T</i>. There is some difference
+in the three leads. "The wave <i>P</i> is positive in <i>all
+leads</i>. <i>P</i> to <i>R</i> interval varies slightly in the <i>three leads</i>.
+All the waves of <i>Lead II</i> are greater than those of <i>Leads I</i>
+and <i>III</i>. The wave <i>R</i> is positive in <i>all leads</i>. <i>T</i> is usually
+positive in <i>all leads</i>, but is occasionally negative in Lead
+III. Even in normal individuals there is a considerable
+range of variation in the electrocardiogram which is within
+the limits of the normal." (Hart.) (Fig. 39.)</p>
+
+<div class="figcenter" style="width: 312px;">
+
+<a name="Normal_electrocardiogram" id="Normal_electrocardiogram"></a>
+
+
+<img src="images/fig_039.png" width="312" height="500" alt="Fig. 39.&mdash;Normal electrocardiogram. (After Hart.)" title="Fig. 39.&mdash;Normal electrocardiogram. (After Hart.)" />
+<span class="caption">Fig. 39.&mdash;Normal electrocardiogram. (After Hart.)</span>
+</div>
+
+<p>The <i>P</i> wave is admitted to be the wave of auricular contraction.
+<i>Q</i>, <i>R</i>, <i>S</i>, is the ventricular complex caused, it is<span class="pagenum"><a name="Page_130" id="Page_130">[130]</a></span>
+thought, by the current passing over the ventricles. <i>T</i>
+wave is not yet definitely settled. It has been thought by
+some that it represented actual ventricular contraction and
+its height and shape had some meaning in heart force.
+This is denied by others. Hart defines it as "The final activity
+of the ventricle." The <i>T</i> wave is usually increased
+in size during exercise.</p>
+
+<p>The <i>P-R</i> interval is almost the most important feature
+of the tracing. It is the actual conduction time in fractions
+of a second of the impulse from s-a node to the ventricles.
+Normally this is about 0.2 second or slightly less. Much
+that was hoped for from the electrocardiograph in the clinic
+has not been forthcoming. Its greatest value is in states
+of abnormal conductivity, such as various grades of heart
+block, extrasystoles, whether originating in auricles or in
+either ventricle, abnormalities of rhythm, as flutter and
+fibrillation. It has, however, aided materially in the intelligent
+interpretation of many phenomena heretofore not
+well understood, and has enormously increased our knowledge
+of the physiology and pathologic physiology of the
+heart.</p>
+
+<p>It is not possible to enter farther into the subject here.
+This brief discussion must suffice. The reader is referred
+to works on this subject in connection with diseases of the
+heart.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_131" id="Page_131">[131]</a></span></p>
+<h2><a name="CHAPTER_IV" id="CHAPTER_IV"></a>CHAPTER IV.</h2>
+
+<h3>IMPORTANT CARDIAC IRREGULARITIES
+ASSOCIATED WITH ARTERIOSCLEROSIS</h3>
+
+
+<p>Arteriosclerosis of the aorta, of the coronary arteries,
+or of both, is practically always found in cases dying of
+various cardiac irregularities other than those the result
+of rheumatic cardiac lesions. It is not that arteriosclerosis
+causes the cardiac lesions (although the thickening of the
+walls of the coronary arteries does interfere mechanically
+with the nutrition of the heart muscle), but the arteriosclerosis
+is a part of the tissue reaction in the arteries to
+some set of causes affecting the whole body. It is true
+when one boils down the question to its last analysis, general
+arteriosclerosis may mechanically so interfere with the
+blood supply to tissues that the tissue is thrown out of
+function either in the reduction or even loss of function.
+So it may be that occasionally the arteriosclerosis in the
+arteries supplying the heart is really responsible for the
+cardiac irregularity. The past few years have been fruitful
+ones in increasing our knowledge of the various irregularities
+of the heart. We can do no more than sketch
+briefly some of them in relation to arteriosclerosis.</p>
+
+<p>The chief irregularities are (1) auricular flutter, (2)
+auricular fibrillation, (3) ventricular fibrillation, (4) auricular
+extrasystole, (5) ventricular extrasystole, (6) heart
+block, partial or complete.</p>
+
+
+<h4>Auricular Flutter</h4>
+
+<p>Auricular flutter is an abnormal rhythm characterized by
+very rapid, but rhythmic auricular contractions usually 250
+to 300 per minute. The auricular contractions are so rapid
+that the ventricle can not respond, so that an electrocardiagram<span class="pagenum"><a name="Page_132" id="Page_132">[132]</a></span>
+of a heart in such a state (Fig. 40) shows the
+ventricle beating regularly but at a much slower rate than
+the auricle.</p>
+
+<div class="figcenter" style="width: 459px;">
+
+<a name="Auricular_flutter" id="Auricular_flutter"></a>
+
+
+<img src="images/fig_040.png" width="459" height="500" alt="Fig. 40.&mdash;(After Hart.)" title="Fig. 40.&mdash;(After Hart.)" />
+<span class="caption">Fig. 40.&mdash;(After Hart.)</span>
+</div>
+
+<p>The majority of cases exhibiting this peculiar rhythm are
+over 40 years of age. In many cases sclerosis of the coronary
+arteries as a part of general arteriosclerosis has been
+found. Auricular flutter can be suspected when the pulse
+is regular or not particularly irregular and a fluttering,
+rapid pulsation is seen in the jugular vein on the right side.
+One can only be sure of the condition by making graphic
+records of the heart.</p>
+
+<p><span class="pagenum"><a name="Page_133" id="Page_133">[133]</a></span>Attacks usually come on suddenly and may disappear as
+suddenly, suggesting paroxysmal tachycardia. The patient
+feels a commotion in his chest, dyspnea, precordial distress,
+etc. The attack may last for weeks or months, in which
+case the patient may carry on his usual work but be conscious
+of palpitation in his chest. One may safely assume
+that the flutter is a sign of a failing myocardium and sooner
+or later the heart will pass to the graver stage of auricular
+fibrillation.</p>
+
+
+<h4>Auricular Fibrillation</h4>
+
+<p>In this condition the auricle is widely dilated and over its
+surface are countless twitchings of individual muscles giving
+to the auricle the appearance of a squirming bunch of
+worms. Such a condition may be readily produced in a
+dog's exposed heart by direct faradization of the auricle.
+It should be seen by every physician in order fully to appreciate
+the passive, dilated sac part which the auricle
+plays when in such a state. There is no auricular wave on
+the electrocardiogram (Figs. 41 and 42) only a series of fine
+tremulous lines, and the ventricles beat irregularly with
+many dropped beats and variations in the size and force of
+individual beats. Extrasystoles are also frequent. The heart
+is absolutely irregular. Such a condition is readily recognizable
+as the state of broken compensation. Graphic records
+are not essential as in auricular flutter to establish
+the condition. Inspection of the root of the neck for jugular
+pulsations and examination of the pulse with the patient's
+evident dyspneic, cyanotic, edematous condition settles the
+diagnosis.</p>
+
+<div class="figcenter" style="width: 487px;">
+
+<a name="Auricular_fibrillation" id="Auricular_fibrillation"></a>
+
+
+<img src="images/fig_041.png" width="487" height="500" alt="Fig. 41.&mdash;Electrocardiogram showing auricular fibrillation in Leads I (upper) and II
+(middle and lower). (Courtesy of Dr. G. C. Robinson.)" title="Fig. 41.&mdash;Electrocardiogram showing auricular fibrillation in Leads I (upper) and II
+(middle and lower). (Courtesy of Dr. G. C. Robinson.)" />
+<span class="caption">Fig. 41.&mdash;Electrocardiogram showing auricular fibrillation in Leads I (upper) and II
+(middle and lower). (Courtesy of Dr. G. C. Robinson.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Auricular_fibrillations" id="Auricular_fibrillations"></a>
+
+<img src="images/fig_042.png" width="500" height="218" alt="Fig. 42.&mdash;Auricular fibrillation. (After Hart.)" title="Fig. 42.&mdash;Auricular fibrillation. (After Hart.)" />
+<span class="caption">Fig. 42.&mdash;Auricular fibrillation. (After Hart.)</span>
+</div>
+
+<p>In no case of auricular fibrillation is the heart muscle
+free from extensive fibrous changes. These may be the result
+of general arteriosclerotic changes or may result from
+toxic changes. It is the general consensus of opinion that
+auricular fibrillation may persist for months or even years.
+Some hold that the state of perpetual irregular pulse is
+associated with auricular fibrillation. If that is true, then<span class="pagenum"><a name="Page_135" id="Page_135">[135]</a></span><span class="pagenum"><a name="Page_134" id="Page_134"></a></span>
+auricular fibrillation may last for many years. Patients
+may go about their work but always live with the imminent
+danger of a sudden dilatation of the ventricle and symptoms
+of acute cardiac decompensation.</p>
+
+<p>In these cases the blood pressure is of particular interest.
+It is often stated that the blood pressure is lowered as compensation
+returns and digitalis has exhibited its full action.
+As a matter of fact this statement needs some modification.
+If one takes the highest pressure at the strongest beat,
+which may be only one in a dozen or more, that may be true,
+but that does not represent the action of the much embarrassed
+heart. We know that the circulation is much interfered
+with, that there is hypostatic congestion, that the
+mass action is slow. The pulse pressure is greatly disturbed
+and the head of pressure which should force the
+blood to the periphery is so little that the circulation almost
+ceases.</p>
+
+<p>A count of the cardiac contractions heard with the stethoscope
+and a count of the pulse shows a great discrepancy
+in number. This has been called the "pulse deficit" (Hart).
+In order to arrive at the true average systolic pressure the
+following procedure is done. "The apex and radial are<span class="pagenum"><a name="Page_136" id="Page_136">[136]</a></span>
+counted for one minute, at the same time by two observers,
+(if possible) then a blood pressure cuff is applied to the
+arm, and the pressure raised until the radial pulse is completely
+obliterated; the pressure is then lowered 10 mm.,
+and a second radial count is made; this count is repeated
+at intervals of 10 mm. lowered pressure until the cuff-pressure
+is insufficient to cut off any of the radial waves (between
+each estimation the pressure on the arm should be
+lowered to zero). From the figures thus obtained the
+average systolic blood pressure is calculated by multiplying
+the number of radial beats by the pressures under which
+they came through, adding together these products and
+dividing their sum by the number of apex-beats per minute,
+the resulting figure is what we have called the 'average
+systolic blood pressure.'" (Fig. 43.)</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Pulse_deficit" id="Pulse_deficit"></a>
+
+
+<img src="images/fig_043.png" width="500" height="243" alt="Fig. 43.&mdash;The shaded area represents the pulse deficit; the upper edge is the apex
+rate, the lower edge the radial rate. The broken line indicates the &quot;average systolic
+blood pressure.&quot; (Compare these values with the figures at the bottom of the chart,
+which show the systolic blood pressure determined by the usual method.) (After Hart.)" title="Fig. 43.&mdash;The shaded area represents the pulse deficit..." />
+<span class="caption">Fig. 43.&mdash;The shaded area represents the pulse deficit; the upper edge is the apex
+rate, the lower edge the radial rate. The broken line indicates the &quot;average systolic
+blood pressure.&quot; (Compare these values with the figures at the bottom of the chart,
+which show the systolic blood pressure determined by the usual method.) (After Hart.)</span>
+</div>
+<p>For example: "B. S., April 29, 1910, Apex 131; radial, 101; deficit, 30.</p>
+
+<p>
+BRACHIAL PRESSURE RADIAL COUNT<br />
+<span style="margin-left: 1.5em;">100 mm. Hg.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; 0</span><br />
+<span style="margin-left: 2em;">90&nbsp; mm.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp;13&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;13 x 90 = 1170</span><br />
+<span style="margin-left: 2em;">80&nbsp; mm.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; 47 - 13 = &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 34 x 80 = 2720</span><br />
+<span style="margin-left: 2em;">70&nbsp; mm.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; 75 - 47 = &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 28 x 70 = 1960</span><br />
+<span style="margin-left: 2em;">60&nbsp; mm.&nbsp;&nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 82 - 75 =&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;7 x 60 =&nbsp; &nbsp;420</span><br />
+<span style="margin-left: 2em;">50&nbsp; mm.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp; &nbsp; &nbsp; 101 - 82 = &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 19 x 50 =&nbsp; &nbsp;950</span><br />
+<span style="margin-left: 21em;">&mdash;&mdash;</span><br />
+<span style="margin-left: 16em;">Apex = 131) 7220</span><br />
+<span style="margin-left: 21em;">&mdash;&mdash;</span><br />
+<span style="margin-left: 6em;">Average systolic blood-pressure 55 plus</span><br />
+</p>
+
+<p>B. S., May 11, 1910, Apex 79; radial, 72; deficit 7.</p>
+
+<p>
+BRACHIAL PRESSURE RADIAL COUNT<br />
+<span style="margin-left: 1.5em;">120 mm. Hg.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;0</span><br />
+<span style="margin-left: 1.5em;">110 mm.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;44&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; 44 x 110 = 4840</span><br />
+<span style="margin-left: 1.5em;">100 mm.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; 64 - 44 = &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;20 x 100 = 2000</span><br />
+<span style="margin-left: 2em;">90 mm.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; 72 - 64 =&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;8 x&nbsp; 90 =&nbsp;&nbsp; 720</span><br />
+<span style="margin-left: 21.5em;">&mdash;&mdash;</span><br />
+<span style="margin-left: 16.5em;">Apex = 79) 7560</span><br />
+<span style="margin-left: 21.5em;">&mdash;&mdash;</span><br />
+<span style="margin-left: 1.5em;">Average systolic blood-pressure 95 plus"</span><br />
+</p>
+
+<p>The diastolic pressure in these cases can not be determined
+except approximately. This may be done by using
+an instrument with a dial and noting the pressure where
+the oscillations of the dial hand show the maximum excursion.
+The diastolic pressure is not at all important under
+such conditions of acute cardiac breakdown. It would
+make no difference in treatment whether the case was one<span class="pagenum"><a name="Page_138" id="Page_138">[138]</a></span><span class="pagenum"><a name="Page_137" id="Page_137"></a></span>
+of pure cardiac disease or one of the hypertension groups.
+After the heart has rallied and the circulation is reestablished,
+then a careful determination of the diastolic pressure
+can be made and the prognosis will rest on what is
+found at the compensated stage.</p>
+
+
+<h4>Ventricular Fibrillation</h4>
+
+<p>Ventricular fibrillation as its name implies, is fibrillation
+of the ventricle analogous to that of the auricle, but the
+condition is rarely observed as it is incompatible with life.
+It has been shown that hearts at the time of death at times
+enter a state of fibrillation of the ventricles and that cases
+of sudden death may be due to this condition. Recently
+G. Canby Robinson<a name="FNanchor_12_12" id="FNanchor_12_12"></a><a href="#Footnote_12_12" class="fnanchor">[12]</a> has seen and made electrocardiograms
+of a case of ventricular fibrillation. (Fig. 44.) The case
+was that of a woman forty-five years old, "who had a series
+of attacks of prolonged cardiac syncope, closely resembling
+Stokes-Adams syndrome, from which she recovered."
+During an attack of unconsciousness in which there
+was no apex beat for about four minutes, the electrocardiogram
+was taken. Following this the tracings showed an
+almost regular heart beating at the rate of 85 to 100 per
+minute. The patient had three convulsions and died with
+edema of lungs about 30 hours after the attack of ventricular
+fibrillation.</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Ventricular_fibrillation" id="Ventricular_fibrillation"></a>
+
+
+<img src="images/fig_044.png" width="500" height="169" alt="Fig. 44.&mdash;Upper curve. Record obtained during period of cardiac syncopy at 2:48 p.m., Lead II. Lower curve from dog.
+Ventricular fibrillation observed in the exposed heart. Lead from right foreleg and left hind leg. (Courtesy of Dr. G. C. Robinson.)" title="Fig. 44.&mdash;Upper curve. Record obtained during period of cardiac syncopy at 2:48 p.m., Lead II. Lower curve from dog.
+Ventricular fibrillation observed in the exposed heart. Lead from right foreleg and left hind leg. (Courtesy of Dr. G. C. Robinson.)" />
+<span class="caption">Fig. 44.&mdash;Upper curve. Record obtained during period of cardiac syncopy at 2:48 p.m., Lead II. Lower curve from dog.
+Ventricular fibrillation observed in the exposed heart. Lead from right foreleg and left hind leg. (Courtesy of Dr. G. C. Robinson.)</span>
+</div>
+
+<p>Autopsy revealed chronic fibrous endocarditis of aortic
+and mitral valves, arteriosclerosis, bilateral carcinoma of
+the ovaries, and signs of general chronic passive congestion.</p>
+
+<p>It is possible that the syncopal attacks in this case were
+the result of sclerosis of the vessels supplying the heart
+muscle although careful microscopical examination did not
+throw much light on the ultimate cause.</p>
+
+
+<h4>Extrasystole</h4>
+
+<p>Whenever there is a dropped beat or an intermittent pulse
+one may be sure that it is the result of an extrasystole.<span class="pagenum"><a name="Page_139" id="Page_139">[139]</a></span>
+Such extrasystoles are produced in the ventricle at some
+point other than the regular path of conduction of impulses.
+The extrasystole may have its origin in either the auricle
+or the ventricle. If there is auricular extrasystole it can
+not usually be recognized except by graphic methods. (Fig.
+45.) The ventricular extrasystole on the contrary is commonly
+seen and readily recognized. Most of those seen in
+the clinic have their origin in some part of the ventricular
+wall. Their two characteristics are that they occur too
+early and that they are followed by a pause longer than the
+normal diastolic pause. (Fig. 46.)</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Auricular_extrasystoles" id="Auricular_extrasystoles"></a>
+
+
+<img src="images/fig_045.png" width="500" height="259" alt="Fig. 45.&mdash;Electrocardiogram showing auricular extrasystoles (P). (Courtesy of Dr. G. C.
+Robinson.)" title="Fig. 45.&mdash;Electrocardiogram showing auricular extrasystoles (P). (Courtesy of Dr. G. C.
+Robinson.)" />
+<span class="caption">Fig. 45.&mdash;Electrocardiogram showing auricular extrasystoles (P). (Courtesy of Dr. G. C.
+Robinson.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Ventricular_extrasystole" id="Ventricular_extrasystole"></a>
+
+
+<img src="images/fig_046.png" width="500" height="122" alt="Fig. 46.&mdash;Electrocardiogram showing ventricular extrasystole. Heart rate 56-60
+beats per minute. Note that diastolic pause in which extrasystole occurs is practically
+equal to two normal diastolic pauses. (Courtesy of Dr. G. C. Robinson.)" title="Fig. 46.&mdash;Electrocardiogram showing ventricular extrasystole.... (Courtesy of Dr. G. C. Robinson.)" />
+<span class="caption">Fig. 46.&mdash;Electrocardiogram showing ventricular extrasystole. Heart rate 56-60
+beats per minute. Note that diastolic pause in which extrasystole occurs is practically
+equal to two normal diastolic pauses. (Courtesy of Dr. G. C. Robinson.)</span>
+</div>
+
+<p>When one listens over the chest to a heart when extrasystoles
+are occurring, one suddenly hears a weak beat<span class="pagenum"><a name="Page_140" id="Page_140">[140]</a></span>
+which has taken place rather too early after the previous
+systole to be strong enough to effect the opening of the
+aortic valves. Consequently there is no pulse, the blood
+does not move, and that beat is lost to the circulation.
+Moreover, when the next regular stimulus comes from the
+s-a node it finds the ventricle in a refractory condition,
+having just ceased a contraction, and it is not until the next
+sinus impulse that the ventricle responds normally. (Fig.
+46.)</p>
+
+<p>Patients who have occasional extrasystoles will say that
+all of a sudden the heart turns upside down in the chest.
+Sometimes there is slight sharp twinge of pain. Patients
+are at times quite alarmed about their condition. Provided
+there is no evidence of gross myocardial lesion, the extrasystole
+itself is of no great significance.</p>
+
+<p>While many cases showing pathologic causes for extrasystoles
+have more or less marked arteriosclerosis, there
+are other states in which no arteriosclerosis is found where
+the extrasystole is present.</p>
+
+
+<h4>Heart Block</h4>
+
+<p>As heart block occurs frequently in cases characterized
+by extensive arteriosclerosis, a brief discussion of the essential
+features will be given. It is, however, probable that
+arteriosclerosis is not the cause of any of the cases of heart
+block directly, but it is only a result of the same etiological
+conditions which produce the lesion or lesions which result
+in heart block. We may define heart block as the condition
+in which the auricles and ventricles beat independently
+of each other. There may be delayed conduction (Fig. 47),
+partial (Fig. 48), or complete heart block (Fig. 49). In
+the former there are ventricular silences, during which the
+auricles beat two, three, four, five, even up to nine times,
+with only one ventricular contraction. It is believed by
+most physiologists that the essential factor in the production
+of heart block is an interference in the conduction of<span class="pagenum"><a name="Page_141" id="Page_141">[141]</a></span>
+impulses from the auricles to the ventricles through the
+band of tissue known as the auriculoventricular bundle.</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Delayed_conduction" id="Delayed_conduction"></a>
+
+
+<img src="images/fig_047.png" width="500" height="86" alt="Fig. 47.&mdash;Electrocardiogram showing delayed conduction (lengthening of P-R interval).
+These P-R intervals are quite regular. When irregular there is apt to be extrasystole
+of ventricle or occasional blocking of impulse going to ventricle. (Courtesy of
+Dr. G. C. Robinson.)" title="Fig. 47.&mdash;Electrocardiogram showing delayed conduction (lengthening of P-R interval).... (Courtesy of
+Dr. G. C. Robinson.)" />
+<span class="caption">Fig. 47.&mdash;Electrocardiogram showing delayed conduction (lengthening of P-R interval).
+These P-R intervals are quite regular. When irregular there is apt to be extrasystole
+of ventricle or occasional blocking of impulse going to ventricle. (Courtesy of
+Dr. G. C. Robinson.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Partial_heart_block" id="Partial_heart_block"></a>
+
+
+<img src="images/fig_048.png" width="500" height="383" alt="Fig. 48.&mdash;Electrocardiogram showing partial heart-block in the three leads. Note
+the variability of P-R interval calculated in seconds in Lead II. (Courtesy of Dr.
+G. C. Robinson.)" title="Fig. 48.&mdash;Electrocardiogram showing partial heart-block in the three leads. Note
+the variability of P-R interval calculated in seconds in Lead II. (Courtesy of Dr.
+G. C. Robinson.)" />
+<span class="caption">Fig. 48.&mdash;Electrocardiogram showing partial heart-block in the three leads. Note
+the variability of P-R interval calculated in seconds in Lead II. (Courtesy of Dr.
+G. C. Robinson.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Complete_heart_block" id="Complete_heart_block"></a>
+
+
+<img src="images/fig_049.png" width="500" height="377" alt="Fig. 49.&mdash;Complete heart block. (Courtesy of Dr. G. C. Robinson.)" title="Fig. 49.&mdash;Complete heart block. (Courtesy of Dr. G. C. Robinson.)" />
+<span class="caption">Fig. 49.&mdash;Complete heart block. (Courtesy of Dr. G. C. Robinson.)</span>
+</div>
+
+<p>The bundle of muscles described by His in 1905, connecting
+the auricles and ventricles, has been definitely
+shown to be the path through which impulses having their
+origin in the orifices of the great veins pass to the ventricles.<span class="pagenum"><a name="Page_142" id="Page_142">[142]</a></span>
+The situation and size of this bundle has been thus
+described in man by Retzer:</p>
+
+<p>"When viewed from the left side, the bundle lies just
+above the muscular septum of the ventricles and below the
+membranous septum. In some hearts the muscular septum
+is so well developed that it envelops the bundle. It is then
+difficult to find, but occasionally it can be seen directly
+by means of transmitted light. From the left side the bundle
+can be followed no farther posteriorly than the right
+fibrous trigone, for here the connective tissue becomes so
+dense that it is difficult to dissect it away. The impression
+is, therefore, received that this mass of connective tissue
+forms the insertion of the bundle. The bundle may be followed
+anteriorly until it becomes intimately mixed with the
+musculature of the ventricles.</p>
+
+<p><span class="pagenum"><a name="Page_143" id="Page_143">[143]</a></span>"When viewed from the right side of the heart, the
+bundle can not be seen, because it is covered by the mesial
+leaflet of the tricuspid valve, whose line of attachment
+passes obliquely over the membranous septum. Then, if
+the endocardium is removed from the posterior part of the
+septum of the auricle up to the membranous septum, the
+posterior part of the auriculoventricular bundle will be exposed.
+If, in addition, the membranous septum be removed,
+the bundle may be traced from the point to which it could
+be followed when viewed from the left side as it passes
+posteriorly over the muscular septum. In the region of the
+auriculoventricular junction it loses its compactness, the
+fibers divide, and the bundle seems to fork. One branch
+passes into the superficial part of the valve musculature
+which descends from the auricles, and the other branch
+passes directly into the musculature of the auricle.</p>
+
+<p>"Briefly, the auriculoventricular bundle runs posteriorly
+in the septum of the ventricles about 10 mm. below the
+posterior leaflet of the aortic semilunar valves; with a gentle
+curve it passes posteriorly just over the upper edge of
+the muscular septum and sends its fibers into the musculature
+of the right auricle and of the auricular valves. In
+the heart of the adult the bundle is 18 mm. long, 2.5 mm.
+wide, and 1.5 mm. thick." (Erlanger.)</p>
+
+<p>All normal impulses have their origin in the sino-auricular
+node at the junction of the superior vena cava with
+the right auricle (Fig. 50). From there the impulse travels
+in the wall of the auricle in the interauricular septum to the
+node of Tawara or A-V node (Fig. 51), thence through the
+bundle of His to be distributed to the fibers of the right and
+left ventricles. This sequence is orderly and perfectly
+regular.</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Alternating_periods_of_sinus_rhythm_and_auriculoventricular_rhythm" id="Alternating_periods_of_sinus_rhythm_and_auriculoventricular_rhythm"></a>
+
+
+<img src="images/fig_050.png" width="500" height="95" alt="Fig. 50.&mdash;Showing alternating periods of sinus rhythm and auriculoventricular rhythm.
+(After Eyster and Evans.)" title="Fig. 50.&mdash;Showing alternating periods of sinus rhythm and auriculoventricular rhythm.
+(After Eyster and Evans.)" />
+<span class="caption">Fig. 50.&mdash;Showing alternating periods of sinus rhythm and auriculoventricular rhythm.
+(After Eyster and Evans.)</span>
+</div>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Auriculoventricular_or_nodal_rhythm" id="Auriculoventricular_or_nodal_rhythm"></a>
+
+
+<img src="images/fig_051.png" width="500" height="264" alt="Fig. 51.&mdash;Period of auriculoventricular or &quot;nodal&quot; rhythm following exercise in sitting
+posture. (After Eyster and Evans.)" title="Fig. 51.&mdash;Period of auriculoventricular or &quot;nodal&quot; rhythm following exercise in sitting
+posture. (After Eyster and Evans.)" />
+<span class="caption">Fig. 51.&mdash;Period of auriculoventricular or &quot;nodal&quot; rhythm following exercise in sitting
+posture. (After Eyster and Evans.)</span>
+</div>
+
+<p>It has also been shown that the independent auricular
+and ventricular rates vary somewhat, that of the auricle
+being in general faster than that of the ventricle. A strip
+of mammalian ventricle placed outside of the body in<span class="pagenum"><a name="Page_144" id="Page_144">[144]</a></span>
+proper surroundings will begin to beat automatically at
+the rate of about 40 beats a minute. Experimentally various
+grades of heart block have been produced in the dog's
+heart by more or less compression of the bundle at the A-V
+ring. The block may be partial, when two to nine auricular
+beats occur to every one of the ventricle, up to absolute<span class="pagenum"><a name="Page_145" id="Page_145">[145]</a></span>
+complete block when the auricles and ventricles beat independently
+of one another.</p>
+
+<p>In any stage of partial block, pressure on the vagus nerve<span class="pagenum"><a name="Page_146" id="Page_146">[146]</a></span>
+in the neck produces certain specific changes. (Fig. 52.)
+Robinson and Draper<a name="FNanchor_13_13" id="FNanchor_13_13"></a><a href="#Footnote_13_13" class="fnanchor">[13]</a> have found qualitative differences
+in the two vagi. The right vagus sends most of its fibers to
+the s-a node (Fig. 53) and has a more evident influence on
+the rate and force of the cardiac contractions. The majority
+of fibers from the left vagus are distributed to the A-V
+node so that its most evident action is upon the conductivity
+of the impulse. Pressure then on the right vagus will
+have a tendency to slow the whole heart. Pressure on the
+left vagus will have a tendency to prolong the P-R interval
+until even complete block occurs. Even when the heart
+block is complete, stimulation of the accelerator nerve, as a
+rule, increases the rate of both auricles and ventricles.</p>
+
+<div class="figcenter" style="width: 500px;">
+
+<a name="Influence_of_mechanical_pressure_on_the_right_vagus_nerve" id="Influence_of_mechanical_pressure_on_the_right_vagus_nerve"></a>
+
+
+<img src="images/fig_052.png" width="500" height="69" alt="Fig. 52.&mdash;Influence of mechanical pressure on the right vagus nerve. (After Eyster
+and Evans.)" title="Fig. 52.&mdash;Influence of mechanical pressure on the right vagus nerve. (After Eyster
+and Evans.)" />
+<span class="caption">Fig. 52.&mdash;Influence of mechanical pressure on the right vagus nerve. (After Eyster
+and Evans.)</span>
+</div>
+
+<div class="figcenter" style="width: 356px;">
+
+<a name="Schematic_distribution_of_right_and_left_vagus" id="Schematic_distribution_of_right_and_left_vagus"></a>
+
+
+<img src="images/fig_053.png" width="356" height="500" alt="Fig. 53.&mdash;Schematic distribution of right and left vagus. (After Hart.)" title="Fig. 53.&mdash;Schematic distribution of right and left vagus. (After Hart.)" />
+<span class="caption">Fig. 53.&mdash;Schematic distribution of right and left vagus. (After Hart.)</span>
+</div>
+
+<p>If the block is functional, depending upon some temporary
+overstimulation of the vagus nerve, atropin, which
+paralyzes the endings of the vagus, will naturally lift the
+block. If the block is due to some actual lesion of the bundle
+of His, such as fibrosis, gumma, or other lesion, then
+atropin will have no influence to terminate the block. In
+this manner we are able to distinguish between functional
+and organic heart block.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_147" id="Page_147">[147]</a></span></p>
+<h2><a name="CHAPTER_V" id="CHAPTER_V"></a>CHAPTER V.</h2>
+
+<h3>BLOOD PRESSURE IN ITS CLINICAL APPLICATIONS</h3>
+
+
+<p>It is well to bear constantly in mind the point made over
+and over in this work, that blood pressure is only one of
+many methods of acquiring information. He who worships
+his sphygmomanometer as a thing apart and infallible will
+sooner or later come to grief. Judgment must be used in
+interpreting changes in blood pressure just as judgment is
+essential in properly evaluating any instrumental help in
+diagnosis. One must not forget the personal equation
+which enters into even accurate instrumental recording in
+medicine and surgery.</p>
+
+<p>In this chapter there will be no attempt to quote largely
+from what others have said or thought. Every one has
+his own opinion as to the value of certain methods after he
+has worked with them for a long time. The ideas here expressed,
+except in cases where no opportunity has offered
+to make personal studies, are those gathered from personal
+experience.</p>
+
+
+<h4>Blood Pressure in Surgery</h4>
+
+<p>Careful estimation of the blood pressure in surgical cases
+has, at times, great value. In all surgical diseases the most
+important fact to know is not the systolic pressure, but the
+pulse pressure. If the pulse pressure keeps within the
+range of normal, does not drop much below 30 mm. in an
+adult, then so far as we can tell the circulation is being
+carried on. When the systolic pressure is gradually falling
+and the diastolic remains the same, the circulation is
+failing and unless the pulse pressure can be established
+again the patient will die. Again we see the value of the
+pulse pressure.</p>
+
+<p><span class="pagenum"><a name="Page_148" id="Page_148">[148]</a></span>All prolonged febrile diseases tend to produce a lowering
+of the blood pressure picture. The diastolic does not fall to
+the same extent as the systolic so that there is a pulse pressure
+smaller than normal. This is to be expected from what
+we know of the general depression of the circulation in
+fevers. The blood pressure reading is only a graphic record
+of what we have long known, and enables us from day
+to day accurately to measure the general circulation.</p>
+
+
+<h4>Head Injuries</h4>
+
+<p>It was claimed that in fracture of the skull or in concussion
+much could be gained by frequent estimations of
+the blood pressure. This seemed probable in the light of
+experiments on compressing the brains of dogs by the use
+of bags inserted through trephine openings (Cushing). In
+the clinic, however, it has not been found of any material
+value. It has a value in differentiating a simple fracture,
+let us say, from a case of uremia which is picked up on the
+street with a bump on the head. There the high pressure
+usually found would at once direct attention to the kidneys
+and the newer methods of blood examination would at once
+settle the question. Naturally uremics may also have skull
+fracture. There the diagnosis would be complicated. A
+decompression done at once would be indicated. If the
+skull fracture happened in a uremic, the decompression
+would probably do no harm. In fact, there are some who
+advise decompression for uremia.</p>
+
+
+<h4>Shock and Hemorrhage</h4>
+
+<p>In shock the blood pressure picture is low but the pulse
+pressure drops to abnormally low figures. It seems to me
+that the blood pressure instrument has its greatest value
+in surgery in the warning it gives to the operating surgeon
+in cases of impending shock.</p>
+
+<p>It is well known that the first effect of ether, the commonly<span class="pagenum"><a name="Page_151" id="Page_151">[151]</a></span><span class="pagenum"><a name="Page_150" id="Page_150"></a></span><span class="pagenum"><a name="Page_149" id="Page_149"></a></span>
+used anesthetic, is to raise the blood pressure and
+quicken the pulse rate. The whole blood pressure picture
+is at first elevated (Fig. 54). Soon the whole pressure falls
+slightly but continues at a higher level than normal. The
+diastolic pressure drops back nearly to normal and the increased
+pulse pressure is due almost entirely to the slight
+rise in the systolic pressure. Now the whole duty of the anesthetist
+is to administer the ether so that this ratio of systolic
+and diastolic is maintained throughout the operation.
+Warning comes to him of impending shock before it comes
+to any one in the neighborhood (Fig. 55). Any sudden
+change in the pressure is a signal for increased watchfulness.
+Should the pressure all at once drop he can immediately
+notify the surgeon and institute measures to resuscitate
+the patient.</p>
+
+<div class="figcenter" style="width: 368px;">
+
+<a name="Blood_pressure_record_from_a_normal_reaction_to_ether" id="Blood_pressure_record_from_a_normal_reaction_to_ether"></a>
+
+
+<img src="images/fig_054.png" width="368" height="500" alt="Fig. 54.&mdash;Blood pressure record from a normal reaction to ether. Note that the
+systolic and diastolic rise and fall together. At the end of the anesthetization the pulse
+pressure is practically the same as at the beginning. Compare this with the record in
+Fig. 55, where the operation had to be discontinued on account of the onset of shock." title="Fig. 54.&mdash;Blood pressure record from a normal reaction to ether. " />
+<span class="caption">Fig. 54.&mdash;Blood pressure record from a normal reaction to ether. Note that the
+systolic and diastolic rise and fall together. At the end of the anesthetization the pulse
+pressure is practically the same as at the beginning. Compare this with the record in
+Fig. 55, where the operation had to be discontinued on account of the onset of shock.</span>
+</div>
+
+<div class="figcenter" style="width: 440px;">
+
+<a name="Chart_showing_the_method_of_recording_blood_pressure_during_an" id="Chart_showing_the_method_of_recording_blood_pressure_during_an"></a>
+
+
+<img src="images/fig_055.png" width="440" height="600" alt="Fig. 55.&mdash;Beginning of operative shock. Chart showing the method of recording blood pressure
+during operation.
+
+Note that the pulse and respiration show no remarkable changes, but the blood pressure
+steadily fell, the systolic more than the diastolic so that the pulse pressure was gradually reaching
+the danger point. Further work on this case was stopped following the warning given by the
+blood pressure. The patient was returned to the ward and a week later anesthesia was again
+given, the operation was completed, and the patient had a satisfactory convalescence." title="Fig. 55.&mdash;Beginning of operative shock. Chart showing the method of recording blood pressure
+during operation...." />
+<span class="caption">Fig. 55.&mdash;Beginning of operative shock. Chart showing the method of recording blood pressure
+during operation.
+
+Note that the pulse and respiration show no remarkable changes, but the blood pressure
+steadily fell, the systolic more than the diastolic so that the pulse pressure was gradually reaching
+the danger point. Further work on this case was stopped following the warning given by the
+blood pressure. The patient was returned to the ward and a week later anesthesia was again
+given, the operation was completed, and the patient had a satisfactory convalescence.</span>
+</div>
+
+<p>A method which is widely used is as follows: The anesthetist
+wraps the cuff of one of the dial instruments around
+the patient's arm, and arranges the dial so that it can easily<span class="pagenum"><a name="Page_152" id="Page_152">[152]</a></span>
+be seen by him at all times. This does not in any way interfere
+with the work of the surgeon. Over the brachial artery
+below the cuff is the bell of a binaural stethoscope held
+in place by the strap attachment now on the market. The
+tubes of the stethoscope are long enough to reach conveniently
+to the ear pieces. A watch is pinned to the sheet of
+the table. He has a chart, as illustrated (Fig. 56) on a
+board and makes a dot in every space for five minute intervals.
+By joining the lines a curve is obtained which tells
+at a glance what the circulation is doing. I feel sure that
+more attention and care exercised on the part of the anesthetist
+would be the means of conserving many lives lost
+from shock following operation.</p>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="Method_of_using_blood_pressure_instrument_during_operation" id="Method_of_using_blood_pressure_instrument_during_operation"></a>
+
+
+<img src="images/fig_056.png" width="500" height="398" alt="Fig. 56.&mdash;Showing method of using blood pressure instrument during operation without
+interfering with the operator or assistants. Sheet thrown back to show cuff on
+arm of patient. Anesthetist has chart on table beside him, dial pinned to pad in full
+view, bulb near hand. Extra tubing must be put on the blood pressure instrument." title="Fig. 56.&mdash;Showing method of using blood pressure instrument during operation without
+interfering with the operator or assistants." />
+<span class="caption">Fig. 56.&mdash;Showing method of using blood pressure instrument during operation without
+interfering with the operator or assistants. Sheet thrown back to show cuff on
+arm of patient. Anesthetist has chart on table beside him, dial pinned to pad in full
+view, bulb near hand. Extra tubing must be put on the blood pressure instrument.</span>
+</div>
+
+<p>A sudden drop in the pressure picture may mean a large
+hemorrhage. The gradual return of the pressure picture
+means that the vasomotor mechanism has acted to keep up
+the pulse pressure. Should the diastolic pressure continually
+fall, it may mean that the hemorrhage is still taking
+place (Wiggers).</p>
+
+
+<h4>Blood Pressure in Obstetrics</h4>
+
+<p>One might affirm almost without fear of contradiction
+that the constant determination of blood pressure during
+pregnancy is more important than the examination of the
+urine. Within recent years a number of observers having
+access to a large material, have given the results of their
+findings. There is a striking unanimity of opinion, although
+now and then a difference in minor details.</p>
+
+<p>The blood pressure should be taken frequently during
+pregnancy. The usual and highly essential precautions in
+taking pressure in general apply most particularly in these
+cases. Towards the end of pregnancy the pressure should
+if possible be taken daily and oftener if necessary.</p>
+
+<p>Pressure in women is usually below 120 mm. Many patients
+have a temporary rise in blood pressure during pregnancy,
+due oftenest to constipation, without developing<span class="pagenum"><a name="Page_153" id="Page_153">[153]</a></span>
+other symptoms. This is common to all conditions and has
+no significance. Some think that an abnormally low pressure,
+that is, a systolic below 90 mm., suggests that the
+patient is likely to react unduly to the strain of labor. This
+is denied by others. Among 1000 cases (Irving) the pressure
+was below 90 in only one case. A gradually rising
+pressure precedes albuminuria, as a rule. If there is albumin
+without change in pressure the albumin may usually
+be disregarded. Some think that a pressure over 130 mm.
+systolic should be carefully watched. The danger limit
+is set by some at 150 mm. If the blood pressure from the
+very first is high, it may mean only that that was the patient's
+normal pressure. This calls for increased watchfulness.
+It is held by some that high blood pressure favors
+hemorrhage and probably explains the hemorrhagic lesions
+in the placenta and some viscera in eclampsia and albuminuria.</p>
+
+<p>All are agreed that the most significant change is the
+gradual but sure rise from a low pressure. When this is
+combined with albuminuria the danger of toxemia is imminent.
+The high blood pressure in those under thirty
+years of age seems to be a more certain sign of approaching
+toxemia than the same pressure in those older. The
+pressure falls within a few days to its normal after delivery
+in the toxic cases.</p>
+
+<p>Although the emesis gravidarum is held to be a sign of
+a toxemia of some unknown nature, the blood pressure is
+never raised even in the pernicious form.</p>
+
+
+<h4>Infectious Diseases</h4>
+
+<p>In all infectious diseases the blood pressure tends to be
+lower than normal. During chills the systolic may rise to
+great height due to the violent muscular contractions.</p>
+
+<p>We found the blood pressure of great value in giving
+information concerning the circulation. Again we repeat<span class="pagenum"><a name="Page_154" id="Page_154">[154]</a></span>
+that it is not the systolic alone or the diastolic alone but the
+pulse pressure which we wish to keep informed about. In
+pneumonia we have tried out Gibson's law only to discard
+it. This so-called law is that in pneumonia the systolic
+pressure in millimeters should remain above the figure for
+the pulse rate. When the figure in mm. of pressure is
+equalled by or exceeded by the pulse rate the prognosis is
+grave.</p>
+
+<p>In typhoid fever we have made many estimations at various
+stages of the disease. We can only say that the pressure
+picture tends to fall during the course. The systolic
+falls more than the diastolic so that it is not uncommon
+to see pulse pressures of 20 mm. at the beginning of convalescence
+in spite of the high caloric feeding practiced.
+At the time of perforation the systolic pressure may be
+raised. This is only the reflex from the initial pain. Soon
+the pressure falls and if peritonitis sets in, the pressure is
+exceedingly low and the pulse pressure gradually falls until
+the circulation can no longer be carried on. In large
+hemorrhage the pressure suddenly falls. If only one hemorrhage
+has occurred a gradual rise takes place, but the
+general pressure picture remains at a lower level for days,
+gradually returning where it was before the hemorrhage.</p>
+
+<p>In beginning failure of the circulation we found elevation
+of the foot of the bed about nine inches to be of such
+value that we felt there must be some increase in blood pressure.
+Numerous readings were made covering a period of
+several months. Although we felt certain that the circulation
+was improved, we rarely needed cardiac stimulation,
+we never could prove any increase of blood pressure with
+the sphygmomanometer.</p>
+
+<p>In all infectious diseases there is no help offered by blood
+pressure estimations in diagnosis. The sole and important
+use is that of keeping track of the circulation.</p>
+<p><span class="pagenum"><a name="Page_155" id="Page_155">[155]</a></span></p>
+
+<h4>Valvular Heart Disease</h4>
+
+<p>No rules can be laid down for blood pressure in valvular
+heart disease. Aortic stenosis, the rarest of the valvular
+lesions, is practically always accompanied by high pressure
+picture. Mitral stenosis on the contrary usually shows a
+low pressure picture. Mitral insufficiency may show an
+exceedingly low picture or an exceedingly high picture.
+Aortic insufficiency also may be accompanied by a high
+systolic or by a normal systolic pressure. It depends on the
+etiology. Practically all the rheumatic cases have low pressure,
+the syphilitic cases have a high pressure. It is characteristic
+of all cases of aortic insufficiency that the diastolic
+pressure is low, even as low as 30 mm. The pulse
+pressure is invariably high. Usually there is no difficulty
+in determining the diastolic pressure. The intense third
+tone suddenly becomes dull at the point of diastolic pressure
+and frequently the dull sound can be distinctly heard
+over the artery down to the zero of the scale. If difficulty
+is found in reading the diastolic as the pressure is reduced,
+the estimation may be reversed and the pressure gradually
+increased from zero to the point where the dull tone suddenly
+becomes loud and clear. These points always coincide.</p>
+
+
+<h4>Kidney Diseases</h4>
+
+<p>This has already been discussed somewhat fully in Chapter
+III and will receive more consideration later. It might
+be remarked in passing that in a case of seeming coma
+where albumin is found in the urine but where the blood
+pressure is low or normal, I have found at autopsy in several
+cases pyonephrosis and not chronic nephritis. The
+blood pressure may be useful in differentiating uremic coma
+from the coma of pyonephrosis. Also in the cases of coma
+with anasarca, either the acute, subacute or chronic form
+the blood pressure is not raised as a rule. Other diseases
+of the kidney, as tuberculosis, cancer, infection with pyogenic<span class="pagenum"><a name="Page_156" id="Page_156">[156]</a></span>
+organisms, are not accompanied with any notable
+changes in blood pressure.</p>
+
+
+<h4>Other Diseases, Liver, Spleen, Abdomen, etc.</h4>
+
+<p>Blood pressure is only of value in the above diseases in
+affording information concerning the state of the circulation.
+There is nothing characteristic about the pressure
+in any of these diseases.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_157" id="Page_157">[157]</a></span></p>
+<h2><a name="CHAPTER_VI" id="CHAPTER_VI"></a>CHAPTER VI.</h2>
+
+<h3>ETIOLOGY</h3>
+
+
+<p>The causes of arteriosclerosis are many and varied. No
+two persons have the same resisting power toward poisons
+that circulate in the blood. Some go through life exposed
+to all the infectious diseases without ever becoming infected,
+while others fall easy victims to every disease that
+comes, no matter how careful they may be, and it is quite
+the same in regard to the resistance of the arterial tissues.
+If the tubing is of first class quality and the individual does
+not place too much strain on it, he may live to the biblical
+three-score years and ten, and possess arteries which have
+undergone such slight changes that they are not palpable.
+Such a person is, however, the exception. On the other
+hand, if the tissue is of poor quality, even the ordinary
+wear and tear of life causes early changes in the vessels,
+and a person of forty may have hard arteries.</p>
+
+<p>We have described in a previous chapter the changes
+which normally occur in the arteries as age advances. An
+artery that is normal for a man of fifty years would be
+distinctly abnormal for a boy of fifteen.</p>
+
+<p>Two broad divisions of arteriosclerosis may be made:
+(1) congenital, or the result of inherited tendency; (2)
+acquired.</p>
+
+
+<h4>Congenital Form</h4>
+
+<p>When Dr. O. W. Holmes was asked how to live to the age
+of seventy, he replied that a man should begin to pick his
+ancestors one hundred years before he was born. Our
+parents determine the character of the tissues with which
+we start in life, and this determines our general resistance.
+We might properly speak of congenital arteriosclerosis<span class="pagenum"><a name="Page_158" id="Page_158">[158]</a></span>
+where the affected individual had poor arterial tissue with
+which to begin life, for that, in a sense, is a congenital defect,
+and arterial tissue that is poor in quality is prone to
+disease.</p>
+
+<p>The author is more and more impressed with the part that
+heredity plays in the determination of arterial degeneration.
+Especially does syphilis in the parents or grandparents
+leave its stigma in the succeeding generations in
+the shape of poor arterial tissue which is prone to early
+degeneration. Recently W. W. Graves has called attention
+to a malformation of the vertebral border of the scapula
+which consists in a concavity instead of the normal
+convexity of the bone. To this malformation he has given
+the name, scaphoid scapula. He considers this to be but
+one manifestation of a general lack of development in the
+individual. He speaks of this maldevelopment as a blight
+and considers that syphilis in the ancestors is responsible
+for the condition in the offspring. He finds that even in
+children, the subjects of the scaphoid scapula, the arteries
+are very definitely thickened. While confirmation of his
+observations is lacking, there is no doubt that we must lay
+the blame for much of the arteriosclerosis in our patients
+to the poor quality of arterial tissue transmitted by ancestors
+who have acquired some constitutional disease. It
+may have been syphilis, it may have been the degeneration
+produced by alcohol or other drug. We can not ignore the
+part which heredity plays. The various factors to be considered
+in the production of the acquired form of arteriosclerosis
+appear to me to be but contributory factors to
+a very great extent, the essential and fundamental factor
+being the quality of arterial tissue with which the individual
+is endowed.</p>
+
+<p>Arteriosclerosis may occur in infants. Cases have been
+reported of calcification of the arteries in infants and children.
+The arteriosclerosis may occur without nephritis or
+rise of blood pressure. Cerebral hemorrhage in a child<span class="pagenum"><a name="Page_159" id="Page_159">[159]</a></span>
+of two years has been seen. Heredity in these cases plays
+a most important rôle. In many of the reported cases there
+was no question of congenital syphilis. Aneurysms, single
+or multiple, have been found in the arteries of children,
+and even the pulmonary artery may show sclerotic changes.</p>
+
+
+<h4>Acquired Form</h4>
+
+<p>As a rule the cases usually seen belong in this group
+because it seems as if a connection could be established almost
+always between one or more of the etiologic factors
+to be described and the disease. While this apparently is
+the case, we must never lose sight of the part which the
+quality of the tissue plays. When we leave this out of our
+calculations we undoubtedly make many false deductions.
+When two men of the same age who have been exposed to
+the same conditions as far as we can learn, are found to
+have quite different arteries, the one normal, the other
+thickened, we must postulate congenitally poor tissue on
+the part of the latter. Such tissue readily becomes diseased
+following conditions which would very likely have
+produced no noticeable effect on perfectly normal, healthy
+tissue.</p>
+
+
+<h4>Hypertension</h4>
+
+<p>Hypertension must still be reckoned with in the etiology
+of arteriosclerosis although the rôle that it was thought to
+play does not seem so important. Changes of blood pressure
+alone are not considered by many to be sufficient for
+the production of arteriosclerosis. This may play some
+part, but there are many other factors mostly unknown
+which determine in any case the production of arterial
+lesions.</p>
+
+<p>With every systole of the heart, blood is forced out into
+the arterial system against a certain amount of resistance
+represented by the tonicity of the capillary area, and the
+amount of cohesion between the viscous blood and the walls<span class="pagenum"><a name="Page_160" id="Page_160">[160]</a></span>
+of arterioles. When a dilatation of the capillaries over
+any large area takes place, the blood pressure falls, provided
+there is no compensatory contraction in other areas
+to make up for the decreased resistance in the dilated vessels.
+The viscosity of the blood, as such, probably has
+very little effect on the resistance to the flow. With the
+systole of the heart there is a sudden dilatation of the arch
+of the aorta, and a wave of expansion follows, which is
+transmitted to the periphery and is lost only in the capillaries.</p>
+
+<p>The blood pressure is constantly changing. Physiologically
+there are relatively wide variations in the pressure
+in a perfectly normal individual. There are some
+persons who have hypotension, a blood pressure much below
+the normal. Such persons have usually small hearts,
+small aortas, and they seem to have but little resistance
+to disease. Many diseases, especially the prolonged fevers,
+diminish markedly the blood pressure. Whether the hypertension
+is the cause of the structural changes that are found
+in the walls of the vessels, or is the result of the diminished
+area of the arterial tree through which the same amount
+of blood has to be driven as before the vessel walls became
+narrowed, is still disputed. As has been stated, experimental
+evidence would tend to place the initial blame upon
+the poisons circulating in the blood, which first damage the
+vessel walls. The subsequent changes then produce thickening
+and inelasticity. Some think (Allbutt) that the
+hypertension is primary. There are cases seen clinically
+that lend support to this view and there is experimental
+evidence also (v. Chap. II). Not infrequently individuals
+in middle life begin to show increase of arterial blood pressure
+without discoverable cause. In such case it may be
+that there is slowly progressing chronic nephritis. The
+urine if examined only superficially in single specimens may
+not reveal any abnormalities. Careful functional examination
+by means of the newer tests may reveal functional<span class="pagenum"><a name="Page_161" id="Page_161">[161]</a></span>
+deficiency. It must not be supposed that all cases of increasing
+hypertension are cases of chronic nephritis. The
+opinion has already been expressed (Chap. III) concerning
+this point. Experience has convinced me that the opinion
+expressed in former editions is not altogether correct.</p>
+
+
+<h4>Age</h4>
+
+<p>No age is exempt from the lesions of arteriosclerosis if we
+consider the two groups. However, the disease is seen for
+the most part in persons past middle life. The relative
+frequency with which it is found in the different decades
+depends on so many factors that it is of no value to tabulate
+them. As has been stated, arteriosclerosis of all types is
+an involution process that advances with age. Longevity
+is a question of the integrity of the arterial tissue, and no
+one can tell what sort of "vital rubber" (Osler) any one
+of us has. However, many with poor tubing may make
+such use of it that it will outlast good tubing that is badly
+treated. Unfortunately we have no way of telling early
+enough with just what sort of arterial tissue we are starting
+life.</p>
+
+
+<h4>Sex</h4>
+
+<p>There is no doubt that men are far more prone to arterial
+disease than women are; all statistics are in accord on this
+point. This is explained by the greater exposure of men
+to those conditions of life which tend to produce circulatory
+strain, and so to produce arteriosclerosis, or vice versa.
+Arteriosclerosis in women is not often seen until after the
+fiftieth year. Cases of the most extreme grade of pipe
+stem arteries are, however, seen in old women, and calcified
+arteries are not hard to find among the inmates of an old
+woman's home.</p>
+
+
+<h4>Race</h4>
+
+<p>Some of the most beautiful examples of arteriosclerosis
+in this country are seen in the negro. Not only is this<span class="pagenum"><a name="Page_162" id="Page_162">[162]</a></span>
+disease more frequent in the black race, but the age of onset
+is much earlier than in the Caucasian. The accidents of
+arteriosclerosis, viz., aneurysm, cerebral hemorrhage, etc.,
+are more common among the negro males. The etiologic
+factors that are most often found in the history are the
+prevalence of syphilis and hard physical labor.</p>
+
+
+<h4>Occupation</h4>
+
+<p>Certain occupations have a distinct causal relationship to
+arteriosclerosis; among such are particularly those entailing
+prolonged muscular exercise, especially if much lifting
+is necessary. Every one is familiar with the phenomena
+accompanying the exertion of lifting. The breath is drawn
+in, the glottis is closed, and the muscles of the chest wall
+are held rigidly while the exertion lasts. This causes a
+great increase in blood pressure, and constant repetition
+of this will produce permanent high tension. In hospitals,
+the stevedores as a class have marked arteriosclerosis, and,
+almost without exception, they are comparatively young
+men. Occupations that are accompanied with prolonged
+mental strain, such as now occur to the heads of large manufacturing
+and financial institutions, also predispose to
+early arterial changes. Psychic activity, especially when it
+is accompanied by worry, is a potent factor in the production
+of the increased blood pressure which is the chief factor
+in producing arterial disease. It has been suggested that
+sexual continence in high-strung men produces changes in
+the nervous system which can conceivably lead to the production
+of high tension and further to arteriosclerosis. This,
+however, I can not think has any foundation in fact except
+in so far as such men are prone to live at high speed and
+wear themselves out sooner than the normal person. The
+sexual continence <i>per se</i> is not harmful. There are, however,
+men who seem not to be harmed by the constant wear
+and tear of our modern life. These are the exceptions.</p>
+
+<p>Workers in factories where paint is made and the ingredients<span class="pagenum"><a name="Page_163" id="Page_163">[163]</a></span>
+hand-mixed, are prone to develop arteriosclerosis
+early in life. It has been found that the laborers most apt
+to be victims of lead intoxication are those who are careless
+in their habits of cleanliness, particularly in regard to the
+fingernails. The continuous absorption of lead into the
+system, brings about a condition of hypertension that has
+its inevitable results.</p>
+
+<p>The fact is that any occupation which entails either the
+absorption of toxic substances, or prolonged muscular labor,
+will hasten markedly the onset of arterial disease.</p>
+
+
+<h4>Food Poisons</h4>
+
+<p>The opinion that arteriosclerosis is due in large part to
+poisoning by end products or by-products of protein digestion
+is now receiving much support. Experiments on
+dogs and rabbits have lent some confirmation to chemical
+observations. It has been shown that dogs fed for a long
+time on putrefied meat developed inflammation and degeneration
+of the adventitia and media, with hyperplasia and
+calcification of the intima of many arteries. In the pulmonary
+and carotid arteries, in the vena cavas and myocardium,
+there were extensive necroses and hyaline degeneration.
+Moreover, injections of sodium urate and ergot
+caused necroses in the muscularis and elastica of the aorta,
+pulmonary artery, vena cavas inferior and heart muscle, but
+there was no calcification. Guinea pigs which were fed
+indol in small doses by the mouth over a long period showed
+atheromatous degeneration of the aorta.</p>
+
+
+<h4>Infectious Diseases</h4>
+
+<p>As more study has been given to the arteries in persons
+who have died of the acute infectious diseases, more has
+come to light concerning the effects of the toxins of these
+diseases on the vessel walls. In the arteries of children
+who have died of measles, scarlet fever, diphtheria, cerebrospinal<span class="pagenum"><a name="Page_164" id="Page_164">[164]</a></span>
+meningitis, etc., degenerative changes in the arteries
+occur, modified only by the length of time that the
+toxins have acted.</p>
+
+<p>Thayer has shown that the arteries of those who have
+passed through an attack of moderately severe or severe
+typhoid fever are as a rule more readily palpable than are
+the vessels of persons of corresponding years who have
+never had the disease. Clinically the typhoid toxin appears
+to cause the early production of arteriosclerosis. The
+changes in the arteries occur for the most part, and always
+earlier, in the peripheral arteries, and the media is chiefly
+affected. Minute yellowish patches are found on the aorta,
+carotids, and coronaries. In persons who have passed
+through an attack of one of the fevers, and have later died
+from some other cause, regenerative changes are sometimes
+found to have taken place in the arteries, consisting of an
+ingrowth of elastic fibers from the intact adventitia to the
+diseased media.</p>
+
+<p>That there are some other factors than the infectious disease
+which are concerned in the production of arterial
+changes seems evident from a study<a name="FNanchor_14_14" id="FNanchor_14_14"></a><a href="#Footnote_14_14" class="fnanchor">[14]</a> made recently among
+a group of almshouse inmates ranging in age from 38 to
+90 years. The study included 500 persons of both sexes.
+Careful histories were taken to determine the presence of
+antecedent infectious disease. The radial artery was palpated
+to determine the presence of sclerosis. Among the
+cases giving a history of one infectious disease the following
+table gives the results:</p>
+
+<div class="center">
+<table border="0" cellpadding="4" cellspacing="0" summary="">
+<tr><td align="left">DISEASE&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;</td><td align="left">NO.&nbsp;</td><td align="left">+&nbsp;</td><td align="left">++&nbsp;</td><td align="left">+++&nbsp;</td><td align="left">POSITIVE&nbsp;</td><td align="left">NEGATIVE</td></tr>
+<tr><td align="left">Measles</td><td align="right">47</td><td align="right">10</td><td align="right">6</td><td align="right">12</td><td align="right">28</td><td align="right">19</td></tr>
+<tr><td align="left">Infectious arthritis</td><td align="right">38</td><td align="right">9</td><td align="right">6</td><td align="right">4</td><td align="right">19</td><td align="right">19</td></tr>
+<tr><td align="left">Pneumonia</td><td align="right">30</td><td align="right">5</td><td align="right">8</td><td align="right">5</td><td align="right">18</td><td align="right">12</td></tr>
+<tr><td align="left">Typhoid</td><td align="right">27</td><td align="right">6</td><td align="right">8</td><td align="right">3</td><td align="right">17</td><td align="right">10</td></tr>
+<tr><td align="left">Scarlet fever</td><td align="right">10</td><td align="right">0</td><td align="right">0</td><td align="right">4</td><td align="right">4</td><td align="right">6</td></tr>
+<tr><td align="left">Smallpox</td><td align="right">14</td><td align="right">1</td><td align="right">4</td><td align="right">0</td><td align="right">5</td><td align="right">9</td></tr>
+<tr><td align="left">Miscellaneous</td><td align="right">12</td><td align="right">2</td><td align="right">5</td><td align="right">2</td><td align="right">9</td><td align="right">3</td></tr>
+<tr><td align="left">&nbsp;</td><td align="right">178</td><td align="right">33</td><td align="right">37</td><td align="right">30</td><td align="right">100</td><td align="right">78</td></tr>
+</table></div>
+
+
+<p><span class="pagenum"><a name="Page_165" id="Page_165">[165]</a></span></p>
+<p>A summary of the cases showed: 252 cases without sclerosis;
+248 with sclerosis; 147 cases with infections but no
+sclerosis; 180 cases with infections and sclerosis.</p>
+
+<p>This study failed to throw any positive light on the question.
+Infectious diseases undoubtedly play a certain rôle,
+particularly those continuing a long time and certain particular
+infectious diseases, as measles.</p>
+
+
+<h4>Syphilis</h4>
+
+<p>Syphilis is one of the most important of the etiologic
+factors in the production of arteriosclerosis. It has been
+shown that in 85 per cent of cases of aortic insufficiency in
+persons, usually males, over forty-five years, who did not
+have chronic infective endocarditis, the Wassermann reaction
+was positive. Acute aortitis affecting the ascending
+and transverse portions of the arch of the aorta is very
+commonly seen, and the irregular, scattered, slightly raised,
+yellowish-white patches of sclerosis in the arch which are
+found years after the syphilitic lesion, are considered by
+some to be very characteristic of syphilis. Mesaortitis is
+the primary lesion and acts as a <i>locus minoris resistentiæ</i>
+where an aneurysm forms.</p>
+
+<p>Hypertensive cardiovascular cases have been serologically
+studied, and a positive Wassermann reaction found
+in a large percentage of one series. In fifty cases, 90 per
+cent either gave a positive Wassermann reaction or luetin
+test, were known to have syphilis, or had children with
+hereditary syphilis. This suggests what might be called
+"familial cardiovascular syphilis."</p>
+
+<p>Hypertensive disease is possibly one of the common so-called
+"late" manifestations of syphilis. That syphilis is
+responsible for the arterial disease in the vessels of the
+brain, resulting in apoplexy or sudden cardiac death in middle
+life, has long been known. In fact, it is claimed (Osler)
+that all aneurysms occurring in persons under thirty years<span class="pagenum"><a name="Page_166" id="Page_166">[166]</a></span>
+of age are due to syphilitic aortitis. In the late stages of
+syphilis the arterial lesions may be of a diffuse character.</p>
+
+
+<h4>Chronic Drug Intoxications</h4>
+
+<p>Lead, tobacco, and according to some, tea and coffee, are
+to be classed as causal factors in the production of arteriosclerosis.
+Certain it is that all these substances have a
+tendency to raise the arterial pressure, but whether the
+drug itself causes first a degeneration, and later a hypertension
+results, or vice versa, is not yet positively known.
+We have just mentioned that lead particularly has a marked
+effect in producing arterial lesions. Other drugs as adrenalin,
+barium chloride, physostigmin, etc., while producing
+experimental arteriosclerosis, hardly could produce
+the disease in man. <b>Alcohol</b> has been blamed for much, and
+as an etiologic factor in the production of arteriosclerosis
+formerly was accorded a first place. More recently much
+doubt has been thrown on this supposition by the work of
+Cabot, who showed that the mere drinking of even large
+quantities of spirits had no effect in producing arterial
+disease.</p>
+
+<p>This observation has been recently substantiated by
+Hultgen, who carefully studied clinically 460 cases of
+chronic alcoholism. He says, "There are no cardiovascular
+symptoms which might be termed characteristic of
+chronic alcoholism, unless it be the peculiar fetal qualities
+of the heart sounds which we know as embryocardia. I
+find this very frequent among drinkers, but I can offer only
+a tentative explanation for it, namely the following: Embryocardia
+can only occur with low tension blood pressure,
+and in the absence of renal insufficiency. Hence it
+might be considered as a useful condition of no pathologic
+significance at all. That alcohol is a sclerogenic pharmakon
+and productive of arteriosclerosis with its usual train of
+symptoms may be a fact, but its demonstration would be<span class="pagenum"><a name="Page_167" id="Page_167">[167]</a></span>
+difficult and is really not shown by my tabulations. There
+were cardiovascular changes, such as myocarditis, aortitis,
+valvular heart disease and arteriosclerosis in chronic alcoholics
+in 54.3 per cent of 461 cases, but this by no means
+constitutes a proof of the causal relationship between these
+lesions and the abuse of liquors. I believe it, nevertheless,
+to be good reasoning to ascribe the bulk of cardiovascular
+symptoms to the sclerogenic action of alcohol, while abstaining
+from an interpretation of its pathogenesis." Just
+what rôle <b>tobacco</b> plays is difficult to say. My own opinion
+is, that of itself when used in moderation, it has no ill
+effects. However, as tobacco is a drug that may raise the
+blood pressure, excessive use must be held responsible for
+the production of arteriosclerosis. It is difficult to separate
+its effects from those produced by eating and drinking.</p>
+
+
+<h4>Overeating</h4>
+
+<p>There can be no doubt but that the constant overloading
+of the stomach with rich or difficultly digestible food is
+responsible for a large number of cases of arteriosclerosis.
+Every one must have noted the increase in force and volume
+of the heart beat after the ingestion of a large meal. The
+constant repetition of such processes conceivably can lead
+to damage to the vessel walls through hypertension.</p>
+
+<p>In the metabolism of food in the intestines there are substances
+produced which are poisonous when absorbed directly
+into the circulation. Ordinarily these substances
+are rendered harmless either before absorption or are detoxicated
+in the liver to harmless substances. It is conceivable
+that a constant overproduction of such poisons
+would eventually damage the defensive mechanism of the
+body to such an extent that some of the poisons would
+circulate in the blood. An expression of a surplus of one,
+at least, of these decomposition products is the appearance
+of indican in the urine. It is not believed that indicanuria
+has the importance attached to it which some authors would<span class="pagenum"><a name="Page_168" id="Page_168">[168]</a></span>
+have us believe. It is found too often and in too many varying
+conditions, nevertheless it undoubtedly does reveal the
+presence of perverted metabolism.</p>
+
+<p>In how far the toxins absorbed from the intestinal tract
+are responsible for the production of arterial disease, it is
+not possible to say. Some observers lay great stress on
+this factor as a cause of arteriosclerosis. The author believes
+that the rôle played by the absorption of products of
+perverted intestinal metabolism is an important one. The
+primary change is an increased tension in the arterioles
+which later leads to thickening of the coats of the vessels
+and to the other consequences of arterial disease. A vicious
+circle is thus established which has a tendency to become
+progressively worse.</p>
+
+
+<h4>Mental Strain</h4>
+
+<p>More and more does one become impressed with the fact
+that patients with arteriosclerosis are very often those who
+take life too seriously and either from ambition or from an
+exalted sense of duty lead especially strenuous lives. Not
+always are these persons addicted to drug or liquor habit.
+Many are rather abstemious in their habits. It is not so
+often that we see as a victim of arteriosclerosis, the carefree
+person who laughs his way through life without worrying
+about the morrow. He is not so prone to arteriosclerosis.
+Worry is a far more potent cause of breakdown than
+actual manual work. It is the rule to find thickened arteries
+among neurasthenics. This may be only part of a generalized
+degeneration of all tissue in the body. The blood pressure
+in such persons is usually low. So many men of our
+better class live under a continuous mental strain in the
+business world. The increase in arteriosclerosis cases is
+real, not apparent. The intense mental strain seems to cause
+a marked increase in blood pressure (for short periods of
+mental effort this has been proved) over a period of time<span class="pagenum"><a name="Page_169" id="Page_169">[169]</a></span>
+sufficient to cause permanent changes in the vessel walls.
+The same sequence of events repeats itself; high tension,
+arterial strain, compensatory thickening, hypertrophied
+heart, etc.</p>
+
+<p>Certainly the character of the arterial tissue has much to
+do with the determination of degenerative changes which
+may result from the action of one or more of the etiologic
+factors.</p>
+
+
+<h4>Muscular Overwork</h4>
+
+<p>Muscular overwork is to be reckoned with as an etiologic
+factor. One sees it especially among the laboring class in
+both whites and negroes. Possibly other factors, as alcohol
+and coarse heavy food, contribute to the early arterial
+degeneration. Hypertrophy of the heart occurs in athletes,
+and statistics gathered among the oarsmen especially, show
+a relatively high mortality at the different decades traceable
+to the high tension produced while in training. This
+question deserves more consideration than has been accorded
+it.</p>
+
+
+<h4>Renal Disease</h4>
+
+<p>Chronic disease of the kidneys (contracted red kidney) is
+one of the most certain producers of hypertension; in fact,
+some maintain that high tension, even without demonstrable
+kidney lesions, as revealed by careful urine examinations,
+is a valuable sign pointing to chronic nephritis. This
+is doubted by others, myself among them. Just what causes
+the increase in blood pressure sometimes to over 270 mm.
+of Hg, is not definitely known. It seems most probable that
+it is some poison elaborated by the diseased kidneys and
+absorbed into the general circulation. There it acts primarily
+on the musculature of the arterioles causing tonic
+contraction and an increase of work on the part of the heart
+to force the blood through narrowed channels. One fact is
+certain. We see patients in coma due to renal disease with<span class="pagenum"><a name="Page_170" id="Page_170">[170]</a></span>
+blood pressure much over 200 mm of Hg. As these cases
+clear up, the pressure may fall, and should they seemingly
+recover, the recovery is accompanied with a marked decrease
+in blood pressure, finally reaching the normal for
+the individual. Moreover, in the course of a severe acute or
+subacute nephritis, hypertension is associated with headache,
+partial or total blindness, and drowsiness. When the
+pressure is reduced, all these symptoms disappear.</p>
+
+<p>There is also the chronically shrunken and scarred kidney
+known pathologically as the arteriosclerotic kidney.
+It is probable that there are two groups of cases which we
+may designate: (1) primary; (2) secondary. In the primary
+group the kidney disease antedates the sclerosis of
+the arteries, and the sclerosis is most probably dependent on
+the constant high tension. We know that prolonged hypertension
+will produce severe forms of arteriosclerosis. The
+arterial disease in this group is caused by the renal disease.</p>
+
+<p>In the second group the kidney changes are apparently
+due to the general arteriosclerosis which, affecting the kidney
+vessels, causes changes leading to atrophy and subsequent
+fibrous tissue ingrowth of scattered areas. These
+cases are not necessarily associated with hypertension; on
+the contrary there is more apt to be hypotension. Where
+the first group occurs for the most part in young and active
+middle-aged people, the second group is the result of involutionary
+processes which accompany advanced age.</p>
+
+<p>However careful a urinalysis may be, there is no assurance
+that one can predict the pathologic state of the kidney.
+Often so-called normal urine will be secreted by a badly
+diseased kidney, whereas a urine which contains considerable
+albumin and many casts may be secreted by a kidney
+which is only temporarily the seat of inflammation. What
+matters after all is not the state of the kidney which the
+pathologist describes, but the actual functional response
+of the kidney in the body to the various tests now well
+known.</p>
+<p><span class="pagenum"><a name="Page_171" id="Page_171">[171]</a></span></p>
+
+<h4>Ductless Glands</h4>
+
+<p>At the present time the tendency among some writers
+is to make the ductless glands the responsible agents in
+almost all diseases. Arteriosclerosis is no exception to this
+tendency. Sajous, for example, divides the morbid process
+producing arteriosclerosis into three types; (1) autolytic,
+(2) adrenal, (3) denutrition. In the first type he finds
+the pancreas to be the most important gland. It supplies
+an internal secretion which "takes a direct part in the protein
+metabolism of the tissue cells, and also in the defensive
+reactions within these cells, as well as in the phagocytes and
+in the blood stream." This being the case exaggeration of
+this digestive process has tissue destruction as its result,
+arteriosclerosis among them.</p>
+
+<p>In the adrenal type Sajous argues that adrenalin produces
+lesions experimentally, therefore the adrenal gland
+has a profound influence by its internal secretion in connection
+with the sympathetic system in producing degenerations
+leading to arteriosclerosis.</p>
+
+<p>The denutrition type has as its particular gland the thyroid.
+The sclerotic process in the arteries is due to the lack
+of thyroid as in cases of myxedema. After a long résumé
+of his ideas he concludes "that arteriosclerosis is the result
+of excessive or deficient activity of certain ductless glands,
+the thyroid and adrenal in particular."</p>
+
+<p>No one can dogmatically deny the part which the ductless
+glands may play in the production of arteriosclerosis, but it
+hardly seems that there is enough actual experimental evidence
+to show that they take such an important part as Sajous
+believes. Until further and more convincing evidence
+is offered by competent investigators, I prefer to look with
+some skepticism upon the ductless gland theory of the causation
+of arteriosclerosis. The field lends itself too easily
+to speculation and imagery. Some are already allowing
+themselves the mental debauch of this nature.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_172" id="Page_172">[172]</a></span></p>
+<h2><a name="CHAPTER_VII" id="CHAPTER_VII"></a>CHAPTER VII.</h2>
+
+<h3>THE PHYSICAL EXAMINATION OF THE HEART
+AND ARTERIES</h3>
+
+
+<h4>Heart Boundaries</h4>
+
+<p>In order to be able to estimate the departures from normal
+in the boundaries of the heart, it is essential that there
+be a definite appreciation of the boundaries of the normal
+heart in relation to the chest wall.</p>
+
+<p>It is frequently stated that the right limit of cardiac dullness
+is normally, in the adult, just at the right border of
+the sternum. This is not strictly accurate. Careful dissections
+at the autopsy table and x-ray plates of the chest
+made at a distance of two meters from the tube show that
+the border of the right auricle is from one to one and a
+half and even two centimeters from the edge of the sternum
+at the level of the fourth rib, and on the living subject this
+can be also demonstrated. The right border of the heart
+usually is from 3 to 4 cm. from the midsternal line at the
+level of the fourth rib.</p>
+
+<p>Again there is a term used in defining the apex, known as
+the point of maximum impulse. As this does not always
+coincide with the apex beat and with the outer lower left
+border of the heart, it would be better to use the term apex
+beat.</p>
+
+<p>Normally, then, the cardiac dullness, the so-called relative
+cardiac dullness, begins above at the upper border of the
+third costal cartilage, as a rule, and taking a somewhat
+curved line with the concavity inward, descends to the fifth
+interspace or beneath the fifth rib from 9 to 10 cm. from a
+line drawn through the center of the sternum parallel to its
+length, the midsternal line. This seems to me to be a better
+method of recording the size of the heart than by the<span class="pagenum"><a name="Page_173" id="Page_173">[173]</a></span>
+lines commonly used; viz., the nipple, or midclavicular, or
+parasternal line. Below, the cardiac dullness is merged into
+the tympany from the stomach and the dullness from the
+liver. At the sixth right costosternal articulation there is
+a sharp turn upwards forming at that point with the liver
+the cardiohepatic angle. At the fourth right cartilage or
+the third interspace, the dullness is from one to two centimeters
+from the edge of the sternum. We have then a somewhat
+pear-shaped area or triangular area with the apex at
+the apex of the heart. The so-called absolute cardiac dullness
+does not appear to me to be of any great significance.
+In reality it is the limit of lung resonance and may be
+greater or less, not so much on account of variations in the
+size of the heart, as of variations in size of the lungs and
+shape of the chest wall.</p>
+
+<p>The really crucial question which should always be asked
+is, Is the heart enlarged or decreased in size? The position
+of the apex beat alone can not determine this, neither can the
+limit to the right of the sternum. The distance between
+these two points and the depth of the dullness at a distance
+of 5 cm. from the midsternal line on the left side, will give
+the size of the heart as nearly as can be obtained in the living
+subject. A series of measurements in normal adults
+average 13 to 14 cm. and 9 to 10 cm. respectively. For
+women they are about 1 cm. less in each direction.</p>
+
+<p>The elaborate mechanism known as the orthodiagraph is
+probably the best means of determining the actual limits
+of the heart, but few men have such an expensive instrument,
+and, moreover, at the bedside such an instrument
+could not be used. From comparative measurements I concur
+in the belief of those who affirm that careful percussion
+will furnish equally as accurate limits.</p>
+
+<p>The first step in making an examination of the heart is to
+expose the patient's chest in a good light, and, sitting at his
+right side, carefully inspect the chest. The position of the
+apex beat, heaving, bulging, retraction of interspaces, etc.,<span class="pagenum"><a name="Page_174" id="Page_174">[174]</a></span>
+can easily be seen if visible. After careful inspection has
+given all the data which it is possible to obtain, one next
+lays the palm of the hand over the heart and attempts to
+palpate the apex beat. The thrust of the apex in a hypertrophied
+heart can readily be felt, and one can feel whether
+the heart is regular, irregular, intermittent, or has other
+change in rhythm. The shock of the closing valves, particularly
+the aortic, can be felt, and that and the forcible apical
+impulse are very suggestive signs of hypertrophy and
+hypertension. Thrills may also be felt and can be timed
+in relation to the heart cycle.</p>
+
+
+<h4>Percussion</h4>
+
+<p>It is to percussion that we next proceed, and for the data
+in regard to the size of the heart, it is, for our purpose, the
+most valuable of all the physical methods of heart examination.</p>
+
+<p>First and foremost we wish by percussion to learn the
+actual size of the heart, in other words what is ordinarily
+called the relative cardiac dullness. With the absolute dullness
+we are not concerned. That irregular area represents,
+as has been said, actually the <b>limits of lung resonance</b>. The
+heart may or may not be covered with lung; there may or
+may not be the incisura cardiaca. What I wish to insist
+upon is that the size of the area of absolute dullness can
+give us no data in regard to the size of the heart. What we
+must endeavor to learn is the actual size of the heart as
+nearly as our crude means will permit.</p>
+
+<p>Light, very light, almost inaudible percussion, what Goldscheider
+called "Schwellungsperkussion," must be practiced.
+Use the middle finger of the right (left) hand as the
+hammer and the last joint of the middle finger of the left
+(right) hand pressed firmly against the chest, as pleximeter.
+I believe it is better to place the pleximeter finger parallel
+to the boundary to be limited although some place the finger
+perpendicularly, that is, pointing toward the boundary.<span class="pagenum"><a name="Page_175" id="Page_175">[175]</a></span>
+Now and then it helps to bend the pleximeter finger at the
+second joint, hold it perpendicularly to the chest wall, and
+strike the joint directly in line of the finger. This in my
+hands has been of great assistance in percussing the limits
+of the heart dullness. Pottenger's "light touch palpation"
+is a modification of the light palpation and, to my mind, has
+no very special advantages. Auscultatory percussion is of
+great value at times. The bell of the stethoscope is placed
+over the portion of heart uncovered by lung (should such
+be the case), and with this point as a center the chest is
+lightly and quickly tapped along radii converging toward
+the stethoscope. One soon learns to recognize the change
+of pitch as the tapping reaches the border of the heart. It
+is well to use all methods, especially in difficult cases, and
+to compare the results. Personally I have found that by
+light percussion I can limit with much accuracy the upper,
+right, and left borders of the heart.</p>
+
+<p>There is much to be gained by using light percussion.
+Strong blows set in vibration not only the underlying structures,
+but also more or less of the chest wall. We wish to
+avoid this source of error, we do not wish to differentiate by
+pitch alone. Finally one's pleximeter finger becomes, after
+long practice, so sensitive to changes in the resonance of
+structures lying below it, that there is actual feeling of impairment
+to the slightest degree. This delicate touch is
+what we should endeavor to cultivate.</p>
+
+<p>It is at times of advantage to use immediate percussion.
+This is done by bending the fingers of the striking hand,
+bringing the tips in a line and striking the chest lightly with
+the four fingers as one finger. Some find it easier to percuss
+the dullness due to the heart in this way than by mediate
+percussion.</p>
+
+<p>The little hammer and hard rubber, celluloid, bone, or
+ivory pleximeter does not seem to me to be nearly as good
+as the fingers. Moreover, one always has his hands, but
+may forget his hammer and pleximeter.</p>
+<p><span class="pagenum"><a name="Page_176" id="Page_176">[176]</a></span></p>
+
+<h4>Auscultation</h4>
+
+<p>In auscultating the heart I prefer the binaural stethoscope
+of the Ford pattern. The recent substitution of an
+aluminum bell for the hard rubber bell is an improvement.
+Personally I do not favor the phonendoscope or any of the
+new patent non-roaring instruments now for sale by urgent
+instrument makers. The phonendoscope has its uses, for
+example in auscultating the back when a patient is lying
+in bed or in listening to the heart sounds when a patient is
+under an anesthetic; but for differentiating the murmurs
+and for heart diagnosis, I much prefer the regular bell
+stethoscope.</p>
+
+<p>In arteriosclerosis the two places over which it is important
+to listen are the apex and the second right cartilage,
+the aortic area. Over the former, one gains data in regard
+to the strength of the heart as indicated by the first sound,
+over the latter point, one learns of the tension in the aorta
+by the character of the sound produced when the aortic
+valves close.</p>
+
+<p>The hypertrophy of the heart in arteriosclerosis is invariably
+due to the enlargement and thickening of the left
+ventricle. From the nature of the position which the heart
+assumes in the thorax, this enlargement is downward and
+to the left. The apex beat will therefore be found in the
+fifth or sixth interspace, and definitely at an increased distance
+from the midsternal line. As stated above, it is
+most important that this distance be accurately measured
+and put down in the notes of the case for future reference.
+No satisfactory prognosis can be given unless this is done,
+for the gradual increase or the decrease under treatment in
+the size of the heart can thus be definitely known, and,
+knowing the other factors, a prognosis may be given which
+will be of some value to the patient.</p>
+<p><span class="pagenum"><a name="Page_177" id="Page_177">[177]</a></span></p>
+
+<h4>The Examination of the Arteries</h4>
+
+<p>It is exceedingly difficult at times to affirm definitely that
+an artery, the radial for example, is actually sclerosed.
+Much depends on the sensitiveness of the fingers of him
+who palpates, and much upon the relation of the palpated
+artery to the surrounding, chiefly underlying, structures.
+In the examination of arteries it is well to inspect the body
+for the pulsations caused by them. Frequently an exceedingly
+tortuous artery, such as the brachial, may be seen
+throughout its whole extent and yet the radial appear little,
+if any, thickened by palpation. Again the artery of a
+pulse of high tension which is small in size but full between
+the beats, may not be as sclerosed as one which collapses
+and feels much softer. It is difficult to obtain accurate data
+in regard to the tension in an artery by feeling it with the
+fingers of one hand. One should use both hands. With the
+middle finger of the right (left) hand the artery is compressed
+peripherally, that is, nearest the wrist. The blood
+is then pressed out of the artery with the middle finger of
+the left (right) hand, so as to obliterate completely the
+pulse wave and the two or three inches between the middle
+fingers are felt with the index fingers. By holding the finger
+firmly on the artery near the wrist so as to block any
+wave that may come through the palmar arch by anastomosis
+with the ulnar artery and by releasing pressure on the
+proximal middle finger, some idea may be had of the degree
+of pulse tension. However, no amount of practice can more
+than approximate the tension and when one is surest that
+he can tell how many millimeters of pressure there are, he
+is apt to be farthest wrong when he checks his guess with
+the sphygmomanometer.</p>
+
+<p>Much may be learned from carefully palpating the peripheral
+arteries, and, as a rule, the sclerosis of these arteries
+means general arteriosclerosis, although there are many
+exceptions to this.</p>
+
+<p><span class="pagenum"><a name="Page_178" id="Page_178">[178]</a></span>A more recent method, and one which in the author's
+hands has been found to be valuable, is that proposed by
+Wertheim-Salomonson who palpates the artery not with
+the ball of the finger but with the fingernail. The finger is
+held so that the nail is perpendicular to the surface of the
+skin and the artery is felt with the end of the nail. The sensation
+is perceived at the root and makes use of all the sensitive
+nerve endings there. In this way it is possible to feel<span class="pagenum"><a name="Page_179" id="Page_179">[179]</a></span>
+the arterial wall distinctly, and a little practice will enable
+one to determine whether or not the vessel wall is thickened.
+It is also possible to determine with a considerable degree of
+accuracy the diameter of the artery and the size of the wall
+when the current is cut off by pressure on the proximal side
+of the artery. It is best to have a firm background when
+this "fingernail" palpation is used. This may be obtained
+by palpating the radial artery against the lower end of the
+radius.</p>
+
+<p>Probably the best method of palpating the arteries, especially
+the radial, to determine the degree of sclerosis and
+thickening, is to use the tip of the finger and roll it carefully
+over the artery. The tip of the finger is exceedingly
+sensitive and, moreover, it is a firmer palpating surface
+than the ball, thus enabling one to appreciate degrees of
+sclerosis which could not be differentiated by palpation
+with the soft yielding ball. This finger tip palpation is well
+illustrated in the figures here shown. (Figs. 57 and 58.)</p>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="Finger-tip_palpation_of_the_radial_artery" id="Finger-tip_palpation_of_the_radial_artery"></a>
+
+
+<img src="images/fig_057.png" width="500" height="321" alt="Fig. 57.&mdash;A method of finger-tip palpation of the radial artery. (Graves.)" title="Fig. 57.&mdash;A method of finger-tip palpation of the radial artery. (Graves.)" />
+<span class="caption">Fig. 57.&mdash;A method of finger-tip palpation of the radial artery. (Graves.)</span>
+</div>
+
+<div class="figcenter bord" style="width: 500px;">
+
+<a name="Finger-tip_palpations_of_the_radial_artery" id="Finger-tip_palpations_of_the_radial_artery"></a>
+
+
+<img src="images/fig_058.png" width="500" height="316" alt="Fig. 58.&mdash;Another method of finger-tip palpation of the radial artery. (Graves.)" title="Fig. 58.&mdash;Another method of finger-tip palpation of the radial artery. (Graves.)" />
+<span class="caption">Fig. 58.&mdash;Another method of finger-tip palpation of the radial artery. (Graves.)</span>
+</div>
+
+
+<h4>Estimation of Blood Pressure</h4>
+
+<p>It must be borne in mind at the outset that arteriosclerosis
+and high blood pressure are not always associated. As
+a matter of fact in the severest grades of senile arteriosclerosis
+the blood pressure is usually below the normal
+for the individual's years. However, as high tension is a
+frequent factor in the production of arterial thickening,
+blood pressure readings are of importance.</p>
+
+<p>The instrument which one uses is of minor importance
+provided it is properly standardized. The most important
+feature of the instrument is the cuff. This must be 12 cm.
+wide and be long enough to wrap around the arm several
+times so that the pressure is evenly distributed over the
+whole arm and not over a small portion. One mercury instrument
+we had in the hospital was reported to be at great
+variance with a dial instrument. This mercury instrument
+was provided with a cuff which was short and was tied<span class="pagenum"><a name="Page_180" id="Page_180">[180]</a></span>
+around the arm by means of a piece of tape. This caused
+a tight constriction over a small area and rendered the estimation
+too high. A new, long tailed cuff easily remedied
+the apparent defect in the instrument.</p>
+
+<p>In taking blood pressures the difference from day to day
+of 10 or even 15 mm. of systolic pressure has no great significance.
+Fluctuations of the systolic pressure alone, it is
+insisted upon, have very little meaning. One must take the
+whole pressure picture into consideration and determine
+how the picture changes in order to draw any conclusion in
+regard to the state of the blood pressure. Failure to pay
+attention to this evident point has caused much futile work
+to be written and published.</p>
+
+<p>It is well to emphasize again the point that the blood
+pressure picture consists of the systolic, the diastolic, the
+pulse pressure and the pulse rate.</p>
+
+
+<h4>Palpation</h4>
+
+<p>Hoover has called attention to the direct palpation of the
+femoral artery just below Poupart's ligament as a more accurate
+index of the pressure in the aorta than the palpation
+of the radial artery. Possibly one can obtain a more accurate
+estimate of the blood pressure in this way. This,
+however, is open to dispute. To estimate the blood pressure
+by palpating the radial artery is most deceptive. In
+about 75 per cent of cases one can tell fairly well whether
+the pressure is abnormally high or abnormally low. Small
+variations are impossible to determine. Unquestionably it
+is most advantageous to get into the habit of palpating the
+femoral artery and checking the result with the sphygmomanometer
+so that the fingers may be trained to appreciate
+as accurately as possible changes of pressure.</p>
+
+<p>It may be that one day when the instrument is needed it
+is not at hand. A well-trained touch then becomes a great
+asset.</p>
+<p><span class="pagenum"><a name="Page_181" id="Page_181">[181]</a></span></p>
+
+<h4>Precautions When Estimating Blood Pressure</h4>
+
+<p>There are certain precautions which must be strictly observed
+when deductions are drawn from the manometer
+readings. The psychic factor must be reckoned with. Any
+emotion may cause marked variations in the pressure. Excitement
+and anger are especial sources of error. Even the
+slight excitement arising from taking the first blood pressure
+on a nervous patient especially is apt to give false
+values. Usually the readings must be taken many times at
+the first sitting and the first few may have to be set aside.
+Worry is a potent factor in raising the pressure. A walk
+to the physician's office, especially if rapid, has its effect.</p>
+
+<p>The position of the patient when the blood pressure is
+taken is important. Usually in the office the pressure is
+taken when the patient sits in a chair. He should assume a
+relaxed, comfortable attitude. The readings should be
+made at the same time of day and at the same interval between
+meals. The pressure in both arms should be
+measured and comparisons should be made only between
+readings on the same arm. These precautions may seem
+useless and even somewhat trivial, and the conditions difficult
+to control. But unless they are carefully observed the
+readings will be false, no comparisons can be drawn between
+the readings on different days, and the instrument
+will most probably be blamed. I have known this to happen
+so often that I can not emphasize too strongly the importance
+of controlling all the essential conditions which
+go to make accurate work.</p>
+
+
+<h4>The Value of Blood Pressure</h4>
+
+<p>In the past few years there has been a veritable avalanche
+of blood pressure instrument salesmen who have
+covered the country, sold instruments, and have made many
+startling claims for the instrument. They have emphasized
+its value out of proportion to what the instrument can do<span class="pagenum"><a name="Page_182" id="Page_182">[182]</a></span>
+even in the hands of one familiar will all the defects. Consequently
+it is not necessary to emphasize the value of blood
+pressure. It seems best to utter a few words of caution in
+regard to its interpretation.</p>
+
+<p>The value lies not in the occasional estimation compared
+with some other one reading, but in the frequent estimation
+and in the visualization of the blood pressure picture. For
+the great majority of diseases the blood pressure has no
+particular value except to show that the circulation is not
+materially disturbed. The limits of normal are rather wide,
+so that consideration of the patient's age, sex, build, etc.,
+will give us some idea of a base line, so to speak, for any one
+person. Wide departures from relatively normal figures
+are important, but are not diagnostic or, rather, pathognomonic.
+I can not help but feel that the diastolic pressure is
+<i>the</i> most important part of the blood pressure picture. Persistent
+high diastolic pressure means increased work for the
+heart, which, if acting for a long time against the high
+peripheral resistance, must eventually hypertrophy. The
+arteries become thickened, lose their wonderful elasticity,
+fibrous tissue is deposited in their walls, and the vicious
+circle is established which leads to pathologic hypertension.</p>
+
+<p>Blood pressure readings must be intimately mixed with
+brains in order to be of any great value in diagnosis or
+prognosis.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_183" id="Page_183">[183]</a></span></p>
+<h2><a name="CHAPTER_VIII" id="CHAPTER_VIII"></a>CHAPTER VIII.</h2>
+
+<h3>SYMPTOMS AND PHYSICAL SIGNS</h3>
+
+
+<h4>General</h4>
+
+<p>Well developed arteriosclerosis shows four pathognomonic
+signs: (1) hypertrophy of the heart; (2) accentuation
+of the aortic second sound; (3) palpable thickening of
+the arteries; and (4) heightened blood pressure. However,
+it must not be inferred that these signs must be present in
+order to diagnose arteriosclerosis. It has already been said
+that a very marked degree of thickening, with even calcification
+of the palpable arteries, may occur with absolutely
+no increase of blood pressure, and at autopsy a small flabby
+heart may be found.</p>
+
+<p>While arteriosclerosis is usually a disease which is of
+slow maturation, nevertheless cases are occasionally seen
+which develop rather rapidly. The peripheral arteries have
+been noticed to become stiff and hard in as relatively brief
+a time as two years from the recognized onset of the disease.</p>
+
+<p>Since involution processes are physiologic, as has been
+described (vide infra), arteriosclerosis may assume an
+advanced grade and run its course devoid of symptoms
+referable to diseased arteries. It is doubtful whether the
+sclerosis itself could produce symptoms, except in cases
+later to be described, were it not that the organs supplied
+by the diseased arteries suffer from an insufficient blood
+supply and the symptoms then become a part of the symptom-complex
+of any or all the affected organs.</p>
+
+<p>There are cases, however, in comparatively young persons
+where a combination of certain ill-defined symptoms
+gives a clue to the underlying pathologic processes. These
+symptoms of early arteriosclerosis are the result of slight<span class="pagenum"><a name="Page_184" id="Page_184">[184]</a></span>
+and variable disturbances in the circulation of the various
+organs. Normally there are frequent changes in the blood
+pressure in the organs, but the vasomotor control of normal
+elastic vessels is so perfect that no symptoms are noted by
+the individual. When the arteries are sclerosed, they are
+less elastic and the blood supply is, therefore, less easily
+regulated. At times symptoms occur only after effort. The
+patient may tire more readily than he should for a given
+amount of mental or bodily exercise; he is weary and depressed,
+and occasionally there is noted an unusual intolerance
+of alcohol or tobacco. Vertigo is common, especially
+on rising in the morning or in suddenly changing from a
+sitting to a standing position. Some complain of constant
+roaring or ringing in the ears. There may be dull headache
+that the accurate fitting of glasses does not alleviate.
+Unusual irritability or somnolency with a disinclination
+to commence a new task may be present. Sometimes the
+effort of concentrating the attention is sufficient to increase
+the headache. This has been called "the sign of the painful
+thought." Numbness and tingling in the hands, feet,
+arms, or legs are also complained of, and neuralgias, not
+following the course of the nerves but of the arteries, also
+occur. It is important to remember that the train of symptoms
+resembling neurasthenia in a person over forty-five
+years old may be due to incipient arteriosclerosis. This
+tardy neurasthenia frequently accompanies cancer, tuberculosis,
+diabetes, and incipient general paralysis, as well as
+incipient arteriosclerosis.</p>
+
+<p>Bleeding from the nose, epistaxis, taking place frequently
+in a middle-aged person, sometimes is an early symptom.
+The bleeding may be profuse, but is rarely so large as to be
+positively harmful. In fact, it may do much good in relieving
+tension. Slight edema of the ankles and legs is seen.
+Dyspnea on slight exertion is not uncommon. Dyspeptic
+symptoms are not infrequent, pyrosis (heartburn), a feeling
+of fullness after meals with belching or a feeling of<span class="pagenum"><a name="Page_185" id="Page_185">[185]</a></span>
+weight in the epigastrium. The dyspeptic symptoms may
+be so marked that one might almost speak of a variety of
+arteriosclerosis, the dyspeptic type. For quite a while before
+any symptoms that would definitely fix the case as one
+of undoubted arteriosclerosis, the patient complains that
+foods which previously were digested with no difficulty now
+give him gastric distress. The examination of the stomach
+contents of a patient presenting gastric symptoms reveals
+usually a subacidity. The total acidity measured after the
+Ewald test meal may be only 20 and the free HCl may be
+absent. Attention has been called to an unnatural pallor
+of the face in early arteriosclerosis. Progressive emaciation
+is sometimes seen in cases of arteriosclerosis and may
+be the only symptom of which the patient complains.</p>
+
+
+<h4>Hypertension</h4>
+
+<p>Not all cases of arteriosclerosis are accompanied by increased
+arterial tension. As has been stated in a previous
+chapter, the blood pressure in the arterial system depends
+chiefly on two factors; viz., the degree of peripheral (capillary)
+resistance, and the force of the ventricular contraction.
+The highest arterial pressures recorded with the
+sphygmomanometer occur not in pure arteriosclerosis but
+in cases where there is concomitant chronic interstitial disease
+of the kidneys. When this is found there is always
+arteriosclerosis more or less marked. In cases where the
+arteries are so sclerosed that they feel like pipe stems there
+may be an actual decrease in the blood pressure. Hence
+the clinical measuring of the pressure in the brachial artery
+alone is not sufficient for a diagnosis of arteriosclerosis. A
+persistent high blood pressure even with normal urinary
+findings is not a sign of arteriosclerosis. The high tension
+later may lead to the production of sclerosis of the arteries,
+but in these cases the kidney may be primarily at fault.</p>
+
+<p>The impression must not be gained that hypertension in<span class="pagenum"><a name="Page_186" id="Page_186">[186]</a></span>
+itself always constitutes a disease or even a symptom of disease.
+Hypertension itself is practically always a compensatory
+process. That is to say, it is the attempt on the part
+of the body to equalize the distribution of blood in the body
+when there is some poison causing constriction of the small
+arteries. In this sense hypertension is not only essential,
+but actually life-saving. A heart which is so diseased that
+it can not respond to the call for increased action by hypertrophy
+of its fibers, would shortly wear out. The very fact
+that the heart becomes enlarged and the tension in the
+arteries becomes high, indicates that in such a heart there
+was great reserve power. But while hypertension is largely
+an effort at adjustment among the various parts of the circulation,
+it nevertheless tends to increase, provided the
+cause or causes which produced it act continuously. Moreover,
+as has been said (Chap. II), the arterioles do not respond
+to increased work on the part of the heart by expanding,
+but by contracting. A vicious circle is thus maintained
+which eventually must lead to serious consequences.</p>
+
+<p>Hypertension is then, if anything, only a symptom which
+may or may not demand treatment. That hypertension
+leads to the production of sclerosis of the arteries has been
+repeatedly affirmed here. In certain cases it is good and
+should not be experimented with. In other cases it is bad
+and some treatment to reduce the tension must be tried.
+The main point is to regard hypertension as one regards a
+compensated heart lesion.</p>
+
+<p>Prof. T. Clifford Allbutt divides the causes of arteriosclerosis
+clinically into three classes: (1) The toxic class&mdash;the
+results of poisons of the most part of extrinsic origin,
+chiefly those of certain infections. In some of these
+diseases, the blood pressures, as for example, in syphilis,
+are ordinarily unaffected; in others, as in lead poisoning,
+they are raised. (2) The class he calls hyperpietic,<a name="FNanchor_15_15" id="FNanchor_15_15"></a><a href="#Footnote_15_15" class="fnanchor">[15]</a> in<span class="pagenum"><a name="Page_187" id="Page_187">[187]</a></span>
+which an arteriosclerosis is the consequence of tensile
+strength, of excessive arterial blood pressure persisting for
+some years. A considerable example of this class is the
+arteriosclerosis of granular kidney, but in many cases kidney
+disease is, clinically speaking, absent. (3) The involutionary
+class, in which the change depends upon a senile, or
+quasisenile degradation. This may be no more than wear
+and tear, a disposition of all or of certain tissues to premature
+failure&mdash;partly atrophic, partly mechanical&mdash;under
+ordinary stresses; or it also may be toxic, a slow poisoning
+by the "faltering rheums of age." In ordinary cases
+of this class the blood pressures for the age of the patient
+are not excessive. Although the toxins of the specific
+fevers, notably typhoid, as stated above, and influenza, have
+been shown to produce arteriosclerosis, this, under favorable
+circumstances he believes tends to disappear. This
+has been shown by Wiesel.</p>
+
+<p>As the blood pressure is dependent on the resistance
+offered by the capillaries and arterioles, there are only two
+ways in which increased pressure can be brought about;
+either by rendering the blood more viscous, or by the generation
+of some poison from the food taken into the body
+which, acting on the vasomotor center or directly on the
+finer vessels, arteriolar or capillary, sets up a constriction
+over any large area, and mainly in the splanchnic area. In
+regard to the liability to arteriosclerosis, this area stands
+second only to the aortic and coronary areas. He believes
+that arteriosclerosis itself has little effect in raising arterial
+pressure. Many cases are seen in which with extreme arteriosclerosis
+there was no rise in blood pressure, and some
+in which pressures have been rising even long before the
+appearance of arterial disease. Prof. Allbutt also believes
+that in the hyperpietic cases the arteries undergo a transient
+thickening, which can be removed if the causes can be
+reached and overcome.</p>
+
+<p>Clinically speaking, then, hyperpietic arteriosclerosis is<span class="pagenum"><a name="Page_188" id="Page_188">[188]</a></span>
+not a disease, but a mechanical result of disease. If the narrowing
+of the arterioles is brought about by thickening due
+to arteriosclerosis, then it would seem <i>a priori</i> that such
+obliteration should cause a rise in pressure. Were the
+vascular system a mere mechanical set of tubes and a pump,
+this would happen, but other factors of great importance
+must be taken into consideration besides the mechanical
+factors; viz., chemical and biological factors. Thus, whole
+parts may be closed and with compensatory dilatation in
+other parts there would be little or no change in pressure,
+unless there were hyperpiesis. In established hyperpiesis,
+we note two conditions in the radial artery: first, a comparatively
+straight vessel with a small diameter; secondly, a
+larger, more tortuous vessel, "the large leathery artery."
+In the cases of the first group, hyperpiesis is often more
+marked, although not appearing so to the examining finger,
+than in the second class. In view of the difficulty of estimating
+by touch alone the amount of hyperpiesis in a contracted
+hard artery, it is often overlooked until a ruptured
+vessel in the brain startles us to a realization of our mistake.
+The "narrow" artery is more dangerous than the
+tortuous one, for with every change in pressure the passive
+vessels of the brain must receive blood that under normal
+conditions would go to other parts of the circulation.</p>
+
+<p>In involutionary sclerosis there is a gradual thickening
+and tortuosity of the vessel, which although it may be
+greater than in the hyperpietic cases, yet is never so dangerous
+to life. The heart in hyperpiesis hypertrophies and
+dilates, but such a heart is the result, not an integral part,
+of the arterial disease.</p>
+
+
+<h4>The Heart</h4>
+
+<p>When the arterial tree becomes narrowed and the resistance
+offered to the flow of blood thereby is increased, more
+muscular work is required of the left ventricle and according<span class="pagenum"><a name="Page_189" id="Page_189">[189]</a></span>
+to the general laws which govern muscles the ventricle
+hypertrophies. There is an actual increase in number of
+fibers as well as an increase in the size of the individual
+fibers. Some of the best examples of simple hypertrophy
+of the left ventricle are found under such circumstances.
+The chambers as a rule do not dilate until the resistance becomes
+greater than the contraction can overcome, when
+symptoms of broken compensation of the heart take place.
+The hypertrophy of the left ventricle brings more of this
+portion of the heart toward the anterior chest wall. The
+enlargement is toward the left, also, consequently the apex-beat
+is found below and to the left of its usual site, even an
+inch or more beyond the nipple line. The impulse is heaving,
+pushing the palpating hand forcibly up from the chest
+wall. The visible area of pulsation may occupy three interspaces
+and the precordium is seen to heave with every systole.
+On auscultation the second sound at the aortic cartilage
+is ringing, clear, and accentuated. Not infrequently,
+too, the first sound is loud and booming, but has a curious
+muffled sound that may even be of a murmurish quality.
+The leaflets of the mitral valve may be the seat of sclerosis,
+the edges are slightly thickened and do not quite approximate,
+thus causing a definite murmur with every systole.
+This murmur may be transmitted out into the axilla and be
+heard at the inferior angle of the left scapula.</p>
+
+
+<h4>Palpable Arteries</h4>
+
+<p>Not every artery that can be felt is the subject of arteriosclerosis,
+and, as has been stated, palpable arteries being
+more or less a condition of advancing years, judgment as
+to whether the artery is pathologically or physiologically
+thickened may be a matter of individual opinion. A radial
+artery that lies close to the lower end of the radius and can
+actually be seen to pulsate when the hand is held slightly
+extended on the back of the wrist, is easily felt, but must<span class="pagenum"><a name="Page_190" id="Page_190">[190]</a></span>
+not, therefore, be considered a sclerosed artery. The radial
+may be so deeply situated in the wrist of a fat subject that
+it is difficultly palpable. Yet the two cases just described
+may have arteries of identical structure, there being no
+more retrogressive changes in the one than in the other.
+"Experience is fallacious and judgment difficult."</p>
+
+<p>The small, contracted, wiry artery of a chronic nephritic
+may feel like a pipe stem, but if properly felt the mistake
+will not be made of considering such an artery an unusually
+sclerosed one. When the wave is pressed out of such a
+high tension artery, it is found that what seemed to be a
+firm sclerosed vessel, was in reality an artery tightly
+stretched over the column of blood.</p>
+
+
+<h4>Ocular Signs and Symptoms</h4>
+
+<p>It would not exaggerate too much to say that the examination
+of the eye grounds with the ophthalmoscope is the
+most important aid in the early diagnosis of arteriosclerosis.
+Long before there are any subjective symptoms,
+changes can be seen in the blood vessels of the retina which,
+while not always diagnostic, at least call attention to a beginning
+chronic disease. As I become more proficient in the
+use of the ophthalmoscope, I am impressed with the importance
+of the ocular signs of arterial disease. I would urge
+practitioners to familiarize themselves with this instrument.
+The electrically lighted instruments on the market now have
+so simplified the technic that any physician should be able
+to see the grosser changes which take place in the arteries
+and veins of the retina and in the disc. Frequently the
+ophthalmologist is the first to recognize early arteriosclerosis.
+In the fundus are seen increased tortuosity of the retinal
+vessels and their terminal twigs with more or less bending
+of the vessels at their crossings. The arteries are terminal
+ones, and small patches of retinitis are therefore found.
+The changes have been divided into (1) suggestive, (2)
+pathognomonic.</p>
+<p><span class="pagenum"><a name="Page_191" id="Page_191">[191]</a></span></p>
+<p>Under (1) are:</p>
+
+<p>(a) Uneven caliber of the vessels,</p>
+
+<p>(b) Undue tortuosity,</p>
+
+<p>(c) Increased distinctness of the central light streak,</p>
+
+<p>(d) An unusually light color of the breadth of the
+artery.</p>
+
+<p>Under (2) are:</p>
+
+<p>(a) Changes in size and breadth of the retinal arteries
+so that they look beaded,</p>
+
+<p>(b) Distinct loss of translucency,</p>
+
+<p>(c) Alternate contractions and dilatations in the veins,</p>
+
+<p>(d) Most important of all, the indentation of the veins
+by the stiffened arteries.</p>
+
+<p>There is yet another sign which appears to be pathognomonic.
+The arteries are pale, appear rigid and through the
+center, parallel to the course, is a rather bright, fine threadlike
+line. The appearance is known as the "silverwire"
+artery. It is particularly constant in hypertension where
+the most beautiful examples are seen.</p>
+
+<p>Moreover, there is the arcus senilis, the fine translucent
+to opaque circle surrounding the outer portion of the iris.
+Practically every one with a well-marked arcus senilis has
+arteriosclerosis, but vice versa not every one with even
+marked arteriosclerosis has an arcus senilis.</p>
+
+<p>In general, the symptoms are gradual loss of acute vision,
+and attacks of transient loss of vision. The explanation
+which has been offered for these phenomena is the contraction
+in a diseased central artery.</p>
+
+
+<h4>Nervous Symptoms</h4>
+
+<p>The onset of arteriosclerosis is, in the majority of cases,
+so insidious that certain nervous manifestations, due in all
+probability to disturbances in blood pressure, are present
+long before the actual sclerosis of the arteries can be felt.<span class="pagenum"><a name="Page_192" id="Page_192">[192]</a></span>
+These nervous symptoms are at times the sign posts to show
+us the way to accurate diagnosis. There may be gradual
+increase in irritability of temper, inability to sleep,
+vertigo even extending to transient attacks of unconsciousness.
+Loss of memory for details frequently is an early
+symptom of sclerosis of the cerebral arteries. Nervous indigestion
+may be present. Various paresthesias as numbness,
+tingling, a sense of coldness or of heat or burning, a
+sense of stiffness or even actual stiffness or weakness may
+occur in the arms and legs, more frequently in the legs.
+The pain complained of may be due to occlusion of an artery,
+although evidence for this is lacking. It has been
+thought by some that the pain in angina pectoris might be
+due to this cause.</p>
+
+<p>Several curious and interesting diseases which have
+been thought by some to have arteriosclerosis as a basis are
+accompanied by pain. Such are erythromelalgia, Raynaud's
+disease, "dead fingers," and intermittent claudication.</p>
+
+<p>Erb has reported a large series of intermittent limp
+(claudication) from his private practice. He finds that the
+large majority of the cases occur in men. The abuse of
+tobacco was evidently the main etiologic factor in about
+half of the cases. Repeated exposure to cold and the abuse
+of alcohol were responsible for most of the other cases.
+Curiously enough he finds that a history of syphilis was
+present in only a small proportion of his cases. It is his
+firm conviction that intermittent limping&mdash;which he thinks
+should be called angiosclerotic dysbasia&mdash;is frequently incorrectly
+diagnosed. It is mistaken for other troubles and
+treated wrongly. As gangrene may develop this is particularly
+dangerous. The affection generally develops gradually,
+although he has seen cases where the onset was rather
+acute. The partial or complete lack of the pulse in the foot
+is the one striking sign, together with the varying behavior
+of the pulse, its disappearance when the feet are cold and<span class="pagenum"><a name="Page_193" id="Page_193">[193]</a></span>
+its return after a warm foot bath or under other treatment.
+Signs of general arteriosclerosis were present in nearly
+every case. When there is a tendency to the development
+of intermittent limp he finds that a valuable sign is the manner
+in which the leg blanches when it is lifted repeatedly
+while the patient is recumbent and becomes hyperemic later
+when placed horizontally. In health this change occurs
+more rapidly.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_194" id="Page_194">[194]</a></span></p>
+<h2><a name="CHAPTER_IX" id="CHAPTER_IX"></a>CHAPTER IX.</h2>
+
+<h3>SYMPTOMS AND PHYSICAL SIGNS</h3>
+
+
+<h4>Special</h4>
+
+<p>Our conception of arteriosclerosis as a degenerative process
+affecting the vascular tree rather than a disease, removes
+the possibility of discussing special symptoms. As
+a matter of fact, we know of very few organs where even
+profound pathologic changes in the vascular system produced
+during life any symptoms which could be laid to
+these arterial changes. Kind nature has given to us such
+an excess of organs of every kind that the destruction of
+large portions of any organ seems to affect the function
+but little. So only particular groups of organs, which show
+symptomatic changes as the result of arteriosclerotic processes,
+will be discussed. It is realized that this may not
+give Teutonic completeness to the discussion, but it certainly
+saves paper and has a distinct practical value to the
+long suffering reader.</p>
+
+<p>Although arteriosclerosis is a disease which affects the
+whole arterial system, it nevertheless never reaches the
+same grade all over the body. The difference in the structure
+and functions of the various organs determines to great
+extent the eventual symptomatology. Endarteritis obliterans
+of a small sized artery in the liver or leg would lead to
+no marked symptoms, as the circulation is so rich that the
+anastomoses of the blood vessels would soon establish a
+collateral circulation that would be perfectly competent to
+sustain the function of the part. Quite different would it
+be should one of the small arteries of the brain, the lenticulo-striate,
+for example, which supplies the corpus striatum,
+become the seat of a thrombosis or embolism caused by
+arteriosclerosis. The arteries of the brain are terminal<span class="pagenum"><a name="Page_195" id="Page_195">[195]</a></span>
+arteries and the blood supply would be cut off entirely with
+a resulting anemic necrosis of the part supplied by the
+artery and a loss of function of the part. What would be
+of no moment in the leg or arm might prove even fatal in
+the brain.</p>
+
+<p>The further symptomatology, therefore, of arteriosclerosis
+depends entirely on the organ or organs most affected
+by the interference with the blood supply. The following
+groups may be recognized:</p>
+
+<p>
+1. Cardiac.<br />
+<br />
+2. Renal.<br />
+<br />
+3. Abdominal.<br />
+<br />
+4. Cerebral.<br />
+<br />
+5. Spinal.<br />
+<br />
+6. Local vasomotor effects.<br />
+<br />
+7. Pulmonary.<br />
+</p>
+
+
+<h4>Cardiac</h4>
+
+<p>Most cases of arteriosclerosis sooner or later present
+symptoms referable to the heart. When the organ is hypertrophied
+and is already working against an enormous
+peripheral resistance, a slight excess of work put upon it
+may cause a dilatation of the chambers with the resulting
+broken compensation. There is dyspnea on slight exertion,
+possibly some precordial distress, slight edema of the ankles
+and lower legs and possibly scanty urine. With proper
+care, a patient with such symptoms may recover, but the
+danger of another break in compensation is enhanced. The
+next attack is more severe. The edema is greater, there
+may be signs of edema of the lungs, effusions into the serous
+cavities may occur. The heart shows marked dilatation.
+There is gallop or canter rhythm and there are loud murmurs
+at the apex. When a patient is first seen in this stage,
+it may be quite impossible to state whether or not there is
+true valvular disease of the heart. The muscle is usually
+diseased in that there is fibroid degeneration of more or<span class="pagenum"><a name="Page_196" id="Page_196">[196]</a></span>
+less extensive character. This factor causes the heart to
+lose much of its elasticity and increases the tendency to
+permanent dilatation. Such cases must be watched before
+one can say that true valvular insufficiency is not present.
+The fatal termination of such a case is quite like that of
+true valvular disease. There is increasing dyspnea, increasing
+anasarca, and the patient usually succumbs to
+edema of the lungs, drowned in his own secretions.</p>
+
+<div class="figcenter" style="width: 422px;">
+
+<a name="Aneurysm_of_the_heart_wall" id="Aneurysm_of_the_heart_wall"></a>
+
+
+<img src="images/fig_059.png" width="422" height="500" alt="Fig. 59.&mdash;Aneurysm of the heart wall. (Milwaukee County Hospital.)" title="Fig. 59.&mdash;Aneurysm of the heart wall. (Milwaukee County Hospital.)" />
+<span class="caption">Fig. 59.&mdash;Aneurysm of the heart wall. (Milwaukee County Hospital.)</span>
+</div>
+
+<p>A very rare complication of the fibroid degeneration of
+the heart muscle is aneurysm of the heart wall. (Fig. 59.)<span class="pagenum"><a name="Page_197" id="Page_197">[197]</a></span>
+The apex of the left ventricle is most commonly the site of
+the aneurysm and rupture occasionally occurs. Such an accident
+is rapidly fatal. In the arteriosclerotic process which
+occurs at the root of the aorta, the coronary arteries become
+involved both at the openings and along the courses of the
+vessels. A branch or branches or even one artery may
+become blocked as a result of obliterating endarteritis.
+The arteries of the heart are not terminal vessels but as a
+rule blocking of a large branch leads to anemic infarct.
+These areas become replaced by fibrous tissue which in the
+gross specimen appears as streaks of whitish or yellowish
+color in the musculature. Anemic infarcts may not occur.
+In such cases the anastomosis between branches of the coronary
+arteries is unusually free. Through arteriosclerosis
+of the coronary vessels extensive fibrous changes may occur
+that lead to a myocardial insufficiency with its attending
+symptoms&mdash;dyspnea, irregular and intermittent heart,
+gallop rhythm, edema, etc. One of the most distressing
+and dangerous results of sclerosis of the coronary arteries
+and of the root of the aorta is angina pectoris. While in
+almost every case of angina pectoris there is disease of the
+coronary arteries, the contrary does not hold true, for most
+extensive disease, even embolism, of the arteries is frequently
+found in persons who never suffered any attacks of
+pain. This symptom group is more common in males than
+in females and as a rule occurs only in adult life. "In men
+under thirty-five syphilitic aortitis is an important factor."
+(Osler.)</p>
+
+<p>Since the valuable experiments of Erlanger on heart
+block, considerable attention has been paid to lesions of the
+Y-shaped bundle of fibers, a bundle arising at the auriculoventricular
+node and extending to the two ventricles,
+known also as the auriculoventricular bundle of His.
+Interference with the transmission of impulses through this
+bundle gives rise to the symptom group known as the
+Stokes-Adams syndrome, which is characterized by: (a)<span class="pagenum"><a name="Page_198" id="Page_198">[198]</a></span>
+slow pulse, (b) cerebral attacks&mdash;vertigo, syncope, transient
+apoplectiform and epileptiform seizures, (c) visible
+auricular impulses in the veins of the neck. Many of the
+cases which occur are in elderly people the subjects of
+arteriosclerosis.</p>
+
+<div class="figcenter bord" style="width: 314px;">
+
+<a name="Large_aneurysm_of_the_aorta_eroding_the_sternum" id="Large_aneurysm_of_the_aorta_eroding_the_sternum"></a>
+
+
+<img src="images/fig_060.png" width="314" height="500" alt="Fig. 60.&mdash;Large aneurysm of the aorta eroding the sternum. Death from rupture through
+the skin preceded by frequent small hemorrhages. (Milwaukee County Hospital.)" title="Fig. 60.&mdash;Large aneurysm of the aorta eroding the sternum. Death from rupture through
+the skin preceded by frequent small hemorrhages. (Milwaukee County Hospital.)" />
+<span class="caption">Fig. 60.&mdash;Large aneurysm of the aorta eroding the sternum. Death from rupture through
+the skin preceded by frequent small hemorrhages. (Milwaukee County Hospital.)</span>
+</div>
+
+<p>So far as we now know all cases of the Stokes-Adams
+syndrome are caused by heart block which is only another
+name for disease in the auriculoventricular bundle. Of
+interest here is the fact that besides gummata, ulcers, and
+other lesions of the bundle, definite arteriosclerotic changes
+have been found.</p>
+
+<p>"The investigation of a typical case of Stokes-Adams disease
+has shown that the symptoms of this case are caused
+by some lesion in the heart which gives rise to the condition<span class="pagenum"><a name="Page_199" id="Page_199">[199]</a></span>
+now generally termed heart block. Practically all degrees
+of heart block have been observed, namely, complete
+heart block and partial block with 4:1, 3:1, and 2:1 rhythm,
+and occasionally ventricular silences. These stages occurred
+during recovery.</p>
+
+<p>"Experiments testing the reaction of the heart to various
+extrinsic influences demonstrate that when the block is complete
+the ventricles do not respond to influences presumably
+of vagus origin, although the auricles still respond normally
+to such influences, that effects exerted upon the heart
+presumably through the accelerators still influence the rate
+of the ventricles as well as that of the auricles.</p>
+
+<p>"When the block is partial the rate of the ventricular contraction
+varies proportionally with the rate of the auricular
+contractions but only within certain limits. When these
+limits are exceeded the block becomes more complete, i. e.,
+a 2:1 rhythm may be changed into a 3:1 rhythm, this into
+a 4:1 rhythm, and this into complete block, and vice versa.</p>
+
+<p>"The syncopal attacks are, in all probability, directly dependent
+upon a marked reduction of the ventricular rate.
+Such reductions of the ventricular rate are always associated
+with an increase of the auricular rate, and it is
+believed that the latter is the cause of the former." (Erlanger.)</p>
+
+<p>The epileptiform seizures of the syndrome may be caused
+by the anemia of the brain resulting from failure of the
+heart to supply a sufficient quantity of blood.</p>
+
+<p>The apoplectiform attacks are most probably caused by
+venous congestion when the slowing of the ventricular contractions
+is not sufficient to cause convulsions, but will just
+cause complete unconsciousness.</p>
+
+
+<h4>Renal</h4>
+
+<p>Chronic nephritis, hypertension, arteriosclerosis form a
+most important trinity. Some stoutly affirm that in all
+cases of high tension there is chronic renal disease. Certainly<span class="pagenum"><a name="Page_200" id="Page_200">[200]</a></span>
+the very highest blood pressures which we see occur
+in the chronic interstitial forms of kidney disease. The
+cause is most probably to be sought in some poison which
+is elaborated in the kidney, is absorbed into the circulation
+and acts powerfully either on the vasoconstrictor center
+as a stimulus, or directly on the musculature of the
+small arteries all over the body. Usually hypertension is
+progressive but it may be temporary.</p>
+
+<p>A man, 43 years old, entered the Milwaukee County Hospital
+in uremic coma. The systolic blood pressure was
+280-290 mm. Hg, the diastolic pressure 220 mm. (Janeway
+instrument). Under treatment his blood pressure gradually
+became lower, at the same period the albumin and
+casts gradually disappeared from the urine. In two weeks
+from admission he seemed perfectly well, there were no
+albumin or casts found in the urine, and the systolic blood
+pressure was 136 mm., not a high figure for a muscular man
+of the laboring class. It must be admitted, however, that
+such cases are the exception, not the rule.</p>
+
+<p>Patients suffering from the association of chronic nephritis
+with hypertension die slowly, usually. There is gradual
+development of anasarca. Headache is frequent and
+severe. Pains all over the body may occur. The sight
+may suddenly become dim or may even be lost. Dizziness
+may be complained of and dyspnea is usually marked.
+Cyanosis comes on, the pulse becomes weak, irregular or
+intermittent, heart failure sets in, and the patient dies with
+edema of the lungs.</p>
+
+<p>Another class of renal arteriosclerosis is characterized
+by a small granular kidney in which fibrous changes of a
+patchy character have taken place. These scattered areas
+are the result of obliterating endarteritis of renal arteries
+here and there with consequent anemia, death of cells, and
+replacement by fibrous tissue. It occurs as part of a generalized
+arteriosclerosis in which the whole arterial system
+is the seat of diffuse (senile) sclerosis. The palpable arteries<span class="pagenum"><a name="Page_201" id="Page_201">[201]</a></span>
+are usually beaded or even encircled with calcareous
+deposits and the aorta is the seat of an extensive nodular
+and ulcerating sclerosis. The heart is usually small, shows
+extensive fibrous and fatty changes and possibly the condition
+known as "brown atrophy;" the blood pressure is low.
+Such cases do not show any special symptoms. They are
+anemic, short of breath on exertion, have the appearance
+and show the signs of senility.</p>
+
+<p>In the first group it is, at times, difficult to say whether
+the kidney disease or the arterial disease is the most important.
+From a clinical standpoint the decision is not
+essential as the end results are much the same in both.
+However, when actual uremic symptoms dominate the
+picture, it becomes evident that the disease of the kidney is
+the chief feature in the causation of the symptoms.</p>
+
+
+<h4>Abdominal or Visceral</h4>
+
+<p>There is an important group of cases to which but little
+attention has been paid until quite recently. This is the
+abdominal or visceral type of arteriosclerosis. It has been
+stated that arteriosclerosis of the splanchnic vessels almost
+invariably causes high tension. Among others, Janeway
+has shown that general arteriosclerosis without marked
+disease of the splanchnic vessels does not cause as a rule
+increase of blood pressure.</p>
+
+<p>There are cases in which the brunt of the lesion falls upon
+the abdominal vessels. Such cases have been called
+"angina abdominalis." It has been suggested (Harlow
+Brooks) that this type of arteriosclerosis may be determined
+by constant overloading of the stomach with food,
+especially rich and spiced food. This causes overwork of
+the special arteries connected with digestion and so leads
+to sclerosis of the vessels of the stomach, pancreas, and intestines.
+Personal habits probably influence to great extent
+the production of this more or less <b>localized</b> condition.</p>
+
+<p>The organs supplied by the diseased arteries suffer from<span class="pagenum"><a name="Page_202" id="Page_202">[202]</a></span>
+changes analogous to those occurring in general or local
+malnutrition, such as starvation, old age, or local anemias.
+These changes are atrophy with hemachromatosis (brown
+atrophy) or fatty infiltration and degeneration. Following
+the degenerative changes there result connective tissue
+growth and further limitation of the functionating power of
+the affected organs.</p>
+
+<p>Pain is a more or less constant symptom of visceral
+sclerosis. In the early stages there may be only a sense
+of oppression, of weight, or of actual pressure in the abdomen
+or pit of the stomach. There may be only recurring
+attacks of violent abdominal pain accompanied by vomiting.
+In some cases symptoms of tenderness in the epigastrium,
+pains in the stomach after eating, vomiting and backache
+may suggest gastric ulcer. There may be dyspnea and a
+sense of anguish accompanied with a rapid and feeble pulse.
+Hematemesis may make the symptom group even more like
+ulcer of the stomach, and only the course of the disease
+with the failure of rigid ulcer treatment and the substitution
+of treatment directed toward relief of the arterial
+spasm with resulting betterment, enables one to make a
+diagnosis. The condition may be present for years and the
+symptoms only epigastric tenderness with dizziness and
+sweating on lying down after dinner, as in one of Perutz's
+patients. The attacks are probably due to spasmodic contraction
+of the sclerosed intestinal vessels with a resulting
+local rise in blood pressure. The pains are most probably
+due to the spasm of the intestinal muscles, and some think
+they are located in the sympathetic and mesenteric plexuses.</p>
+
+<p>This result of arteriosclerosis is not so uncommon, and
+by keeping this cause of obscure abdominal pain in mind
+we are now and then enabled to save a patient from operation.</p>
+
+<p>An autopsy on a case which for many years had attacks
+of abdominal pain and cramp-like attacks, with high blood
+pressure and heart hypertrophy, showed extensive sclerosis<span class="pagenum"><a name="Page_203" id="Page_203">[203]</a></span>
+of the abdominal aorta, superior mesenteric and iliacs.
+These vessels were calcified. Hypertrophy of the left
+ventricle was found. The kidneys were microscopically
+normal. There were no changes in the ascending aorta but
+in the descending portion there were scattered nodules and
+small calcified plaques.</p>
+
+<p>The attacks of pain from which this patient suffered for
+many years, the hypertrophy of the left ventricle and the
+increased blood pressure were thought to be directly due
+to the sclerosis of the abdominal vessels.</p>
+
+
+<h4>Cerebral</h4>
+
+<p>It has been stated that arteriosclerosis is a general disease,
+yet certain systems of vessels may be affected far
+more than others, and indeed there may be marked sclerosis
+at one part of the body and none demonstrable at another
+part.</p>
+
+<p>In advanced sclerosis there may be one or more of a series
+of accidents due to embolism, thrombosis, or rupture of the
+vessels. Such conditions as transient hemiplegia, monoplegia
+or aphasia may occur. The attacks may come on
+suddenly and be over in a few minutes; what Allbutt calls
+"Larval apoplexies." They may last from a few hours
+up to a day, and are very characteristic. A patient aged
+64 years with pipe stem radials and tortuous hard temporals
+would be lying quietly in bed when suddenly he would
+stiffen, the eyes would become fixed and the breathing
+cease. In a few seconds consciousness returned, the patient
+would shake himself, pass his hand over his brow and ask,
+"Where am I? Oh, yes, that's all right." He had as many
+as thirty of these attacks in twenty-four hours, none of
+them lasting over one minute. To just what such attacks
+are due, it is hard to say. Some have attributed them to
+spasm of the smaller blood vessels of the brain, but there
+have never been demonstrated in the vessels any constrictor
+fibers.</p>
+
+<p><span class="pagenum"><a name="Page_204" id="Page_204">[204]</a></span>There is a well recognized form of dementia caused by
+arteriosclerosis. In general paralysis of the insane and
+in senile dementia the blood vessels are always diseased.
+Milder grades of psychic disturbances are accompanied by
+such symptoms as mental fatigue, persistent headaches,
+vertigo, memory weakness and fainting. Aphasia, periods
+of excitement and mental confusion occur in some. Later
+stages are at times accompanied by inclination to fabulate,
+loss of judgment, disorientation, narrowing of the external
+interests, episodes of confusion and hallucinatory delirium.</p>
+
+<p>The hemiplegias, monoplegias and paraplegias may occur
+again and again and last for one or two days. Unless
+there has been rupture of the vessels, there is complete recovery
+as a rule.</p>
+
+<p>In persons who have arteriosclerosis with high tension
+attacks of melancholia are seen. There are at the same
+time fits of depression, insomnia, irritability, fretfulness,
+and a generally marked change in disposition. When the
+tension is reduced by appropriate treatment these symptoms
+disappear, to recur when the tension again becomes
+high. On the contrary, attacks of mania are accompanied
+by low blood pressure. The dizziness and vertigo in cerebral
+arteriosclerosis are probably due to the stiffness of the
+vessels which prevents them from following closely the variations
+of pressure produced by position, and thus, at
+times, the brain is deprived of blood and a transient anemia
+occurs.</p>
+
+<p>Arteriosclerosis of the cerebral vessels is always a serious
+condition. The greatest danger is from rupture of a
+blood vessel. Another of the dangers is gradual occlusion
+of the arteries bringing about necrosis with softening of the
+brain substance. The latter is more apt to be associated
+with psychic changes, dementia, etc.; the former, with
+hemiplegia. It is curious that a small branch of the Sylvian
+artery, the lenticulo-striate, which supplies the corpus striatum,
+should be the one which most frequently ruptures.<span class="pagenum"><a name="Page_205" id="Page_205">[205]</a></span>
+Where the motor fibers from the whole cortex are gathered
+together in one compact bundle, a very small hemorrhage
+may and does cause very serious effects. A comparatively
+large hemorrhage in the silent area of the brain may cause
+few or no symptoms.</p>
+
+
+<h4>Spinal</h4>
+
+<p>It is conceivable that arteriosclerosis of the vessels of
+the spinal cord might cause symptoms which would be referred
+to the areas of the cord where the process was most
+advanced. The lesions would be scattered and consequently
+the symptoms might be protean in character.</p>
+
+<p>True epileptic convulsions dependent on arteriosclerotic
+changes are also seen and are not so uncommon.</p>
+
+<p>This is on the whole a rare condition, much less common
+than arteriosclerosis of the cerebral vessels. Collins and
+Zabriskie report the following typical case:</p>
+
+<blockquote><p>"H., a fireman, fifty-one years old, was in ordinary good health until toward
+the end of 1902. At that time he noticed that his legs were growing
+weak and that they tired easily. Later he complained of a jerking sensation
+in different parts of the lower extremities and at times of sharp pain, which
+might last from several minutes to two or three hours. The legs were the
+seat of a heavy, unwieldy sensation, but there was no numbness or other
+paresthesia. About the same time he began to have difficulty in holding the
+urine, a symptom which steadily increased in severity. These symptoms continued
+until March, 1903, i. e., for three months, then he awakened one morning
+to find that he was unable to stand or walk, and the sphincters of the
+bowels and bladder relaxed. There was no complaint of pain in the back or
+legs, no difficulty in moving the arms, in swallowing or in speaking. He says
+he was able to tell when his lower extremities were touched and he could
+feel the bed and clothes. He was admitted to the City Hospital three weeks
+later and the following record was made on April 21, 1903.</p>
+
+<p>"The patient was a frail, emaciated man of medium height, who had the
+appearance of being 55-60 years of age. He was unable to stand or walk.
+When he was lying, he could flex the thigh and the legs slowly and feebly.
+There was slight atrophy of the anterior and inner muscles, more of the left
+than of the right side. The knee jerks and ankle jerks were absent. Irritation
+of the soles caused quite a typical Babinski phenomenon. The patient
+had fair strength in the upper extremities, but the arms tired very soon, he
+said. The grip was moderate and alike in each hand. The motility of the
+face, head, and neck was not noticeably impaired. There was no difficulty<span class="pagenum"><a name="Page_206" id="Page_206">[206]</a></span>
+in swallowing, and articulation was not defective. Tactile sensibility was
+slightly disordered in the lower extremities, although he could feel contact of
+the finger, the point of a pin, and the like. Sensibility was not so acute as
+normal; there was a quantitative diminution. Sensory perception was not
+delayed. There was a distinct zone of slight hyperesthesia about as wide as
+the hand above the femoral trochanters. Above that, sensibility was normal.
+There was no discernible impairment of thermal sensibility. No part of the
+body was particularly tender on pressure. A bedsore existed over the sacrum,
+and there was excoriation of the genitals from constant dribbling of urine.</p>
+
+<p>"Examination of the chest showed shallow respiratory movements. The
+heart was regular, weak, there were no murmurs, the second sound was accentuated.
+Examination of the abdomen showed that the liver and spleen
+were palpable, but were not enlarged. The abdominal reflexes, both upper and
+lower, were sluggish. The patient was slow of speech, likewise apparently of
+thought. He did not seem to show an adequate interest in his condition, still
+he was fully oriented and seemed to have a fair memory. His mental reflex
+was slow. There were indications in the peripheral blood vessels and heart of
+a moderate degree of general arteriosclerosis. The peripheral vessels
+such as the radial, were palpable, the walls thickened, the blood pressure
+increased.</p>
+
+<p>"The patient did not complain of pain while he was in the hospital, a
+period of four weeks, nor was there any particular change in the patient's
+symptoms, subjective and objective, during this time. His mental state remained
+clear until forty-eight hours before death, when he became sleepy,
+stuporous, and comatose, dying apparently of cardiac weakness, which had set
+in simultaneously with the clouding of consciousness."</p>
+
+<p>At autopsy, except for a few small hemorrhages in the posterior horns of
+the lower dorsal segments on the right side and a similar condition of the left
+anterior horns, there was nothing noticed. On microscopic examination, there
+was found widespread sclerosis of the vessels of the cord to a marked degree
+with only slight thickening of the vessels of the brain. There were secondary
+degenerations of ascending and descending type particularly marked at the
+ninth dorsal segment. They included portions of all the tracts, the pyramidal
+tract as well. The symptoms in brief were: (1) weakness and easily induced
+fatigue of the legs; (2) peculiar sensations in the lower extremities, described
+as jerky, numbness, heaviness, and occasionally sharp pain; (3)
+progressive incontinence of urine; (4) progressive paraplegia.</p></blockquote>
+
+<p>Since one of the chief manifestations of syphilis is sclerosis
+of the arteries, neurologic cases characterized by irregular
+symptoms and signs which can not be placed in any of
+the definite system disease groups, are possibly due to
+irregularly scattered areas of sclerosis throughout the
+spinal cord caused by obliterating arteritis. Such cases
+are not so very uncommon. Several have come under my<span class="pagenum"><a name="Page_207" id="Page_207">[207]</a></span>
+observation. Further studies of the spinal cords of these
+cases at autopsy are necessary before a final opinion can
+be given as to their dependence on arteriosclerosis of the
+spinal vessels.</p>
+
+
+<h4>Local or Peripheral</h4>
+
+<p>When the arteriosclerosis in the peripheral arteries
+reaches a stage where endarteritis obliterans supervenes,
+there is usually no chance for a compensatory or collateral
+circulation to be established. The area supplied by the vessel
+undergoes dry gangrene. A portion of a toe or finger or
+a whole foot or hand may shrivel up. It is more common to
+see the spontaneous amputation take place in the lower extremities.
+The same effect may be produced by the plugging
+of a vessel with a thrombus. There may be much pain
+connected with the sudden blocking, whereas the gradual
+obliteration of the blood supply of a toe or foot is not as a
+rule at all painful. The condition is at times revealed more
+or less accidentally when a patient injures his toe or foot
+and discovers that there is no sensation in the part and that
+the wound instead of healing is inclined to grow larger.</p>
+
+<p>Other interesting vasomotor phenomena are frequently
+connected with arteriosclerosis. Such a one is the curious
+condition known as Raynaud's disease, a vascular disorder
+which is divided into three grades of intensity: (1) local
+syncope, (2) local asphyxia, (3) local or symmetrical gangrene.
+This is not the place to describe this condition except
+to say that the condition called "dead fingers" is the
+most characteristic feature of the first stage. Chilblains
+represent the mildest grade of the second stage. The parts
+are intensely congested and there may be excruciating pain.
+Any one who has ever had chilblains knows how painful
+they can be. The general health is not impaired as a rule,
+although the attacks are apt to come on when the person is
+run down. The third stage may vary from a very mild<span class="pagenum"><a name="Page_208" id="Page_208">[208]</a></span>
+grade, with only small necrotic areas at the tips of the
+fingers, to extensive multiple gangrene.</p>
+
+<p>Another and very rare condition in which chronic endarteritis
+was the only constant finding is the disease described
+by S. Weir Mitchell and called by him erythromelalgia (red
+neuralgia). This is "A chronic disease in which a part or
+parts&mdash;usually one or more extremities&mdash;suffer with pain,
+flushing, and local fever, made far worse if the parts hang
+down." (Weir Mitchell.)</p>
+
+<p>Probably the most frequently seen result of arteriosclerosis
+in the leg arteries is the remarkable condition, first described
+by Charcot, known as intermittent claudication.
+Persons the subject of this disease are able to walk if they
+go slowly. If, however, any attempt be made to hurry the
+step, there results total disability accompanied at times by
+considerable cramp-like pain. The condition is much more
+prone to occur in men than in women, and Hebrews seem
+more frequently affected. The cause is most probably to
+be sought in the anemia which results from the narrowing
+of the channels through which the blood reaches the part.
+The stiff, much narrowed arteries allow sufficient blood to
+pass along for the nutrition of the part at rest or in quiet
+motion. Just as soon as more violent exercise is taken,
+calling for more blood, an ischemia of the part supervenes,
+for the stiff vessels can not accommodate themselves to
+changes in the necessary vascularity of the part. A rest
+brings about a gradual return of blood and the function of
+the part is restored. Pulsation may be totally absent in the
+dorsal arteries of the feet and when the legs are allowed to
+hang down there is apt to be deep congestion.</p>
+
+<p>In this connection a curious case reported by Parkes
+Weber will not be out of place. The patient, a male, aged
+42 years, complained of cramp-like pains in the sole of the
+left foot and calf of the leg occurring after walking for a
+few minutes and obliging him to rest frequently. When
+the legs were allowed to hang over the side of the bed, the<span class="pagenum"><a name="Page_209" id="Page_209">[209]</a></span>
+distal portion of the left foot became red and congested
+looking. No pulsation could be felt in the dorsal artery of
+the left foot or in the posterior tibial artery. There was no
+evidence of cardiovascular or other disease. An ulcer on
+the little toe had slowly healed, but cramp-like muscular
+pains still occurred on walking. The disease had lasted
+about five years without the appearance of gangrene.</p>
+
+<p>Weber calls this case one of arteritis obliterans with intermittent
+claudication.</p>
+
+
+<h4>Pulmonary Artery</h4>
+
+<p>In the symptomatology of sclerosis of the pulmonary
+artery the clinical signs and symptoms are mostly referable
+to the obliterating endarteritis of the smaller vessels, while
+the physical signs are more apt to reveal the involvement of
+the main trunk. A history of severe infection in the past
+is frequent, especially smallpox, and accompanying aortic
+sclerosis with insufficiency of the mitral valve or stenosis of
+this valve is the rule. Striking cyanosis is an early symptom,
+while there is little if any dyspnea and edema. Intermittent
+dyspragia is common. There seems to be no
+tendency to clubbed fingers. Repeated hemorrhages from
+the lungs without the formation of infarcts may occur.
+There is usually an area of dullness at the upper left margin
+of the sternum and nearby parts, sensitive to pressure
+and to percussion, and the heart dullness extends unusually
+far towards the right. The diagnosis of the right ventricular
+hypertrophy may be substantiated by a fluoroscopic examination.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_210" id="Page_210">[210]</a></span></p>
+<h2><a name="CHAPTER_X" id="CHAPTER_X"></a>CHAPTER X.</h2>
+
+<h3>DIAGNOSIS</h3>
+
+
+<h4>Early Diagnosis</h4>
+
+<p>Arteriosclerosis is essentially a disease of middle life
+and old age. It is not unusual, however, to find evidences
+of the disease in persons in the third decade and
+even in the second decade. Hereditary influences play
+a most important rôle, syphilis and the abuse of alcohol
+in the family history are particularly momentous. The
+recognition of the early changes in the arteries among
+young persons depends largely upon how carefully these
+changes are looked for. The difference in the point of view
+of one man who finds many cases in the comparatively
+young, and another man who rarely finds such changes early
+in life, at times, depends upon the acuity of perception and
+observation and not upon the fact that one man has had a
+series of unusually young arteriosclerotic subjects. The
+diagnosis of arteriosclerosis may be so easily made that the
+tyro could not fail to make it. It is, however, the purpose
+of this volume to lay stress on the earliest possible diagnosis
+and, if possible, to point out how the diagnosis may be arrived
+at. It is obviously much to the advantage of the patient
+to know that certain changes are beginning in his
+arteries, which, if allowed to go on, will inevitably lead to
+one or more of the symptom groups described in the preceding
+chapters.</p>
+
+<p>The combination of (1) hypertrophied heart, (2) increased
+blood pressure, (3) palpable arteries, and (4)
+ringing, accentuated second sound at the aortic cartilage is,
+in reality, the picture of advanced arteriosclerosis. If the
+individual is in good condition much may be done by judicious<span class="pagenum"><a name="Page_211" id="Page_211">[211]</a></span>
+advice and treatment to ward off complications and
+prolong life with a considerable degree of comfort. But we
+should not wait until such signs are found before making a
+diagnosis and instituting treatment. As in all forms of
+chronic disease the early diagnosis is all important.</p>
+
+<p>The history of the case is the first essential. Often a careful
+inquiry into the personal habits of a patient, with the
+record of all the preceding infectious diseases will give us
+valuable information and may be the means of directing the
+attention at once to the possible true condition. Particularly
+must we inquire into the family history of gout and
+rheumatism. An individual who comes of gouty stock is
+certainly more prone to arterial degeneration than one who
+can show a healthy heredity. Alcoholism in the family also
+is of importance because of the fact that the children of
+alcoholics start in life with a poor quality of tissue, and
+conditions that would not affect a man from healthy stock
+might cause early degeneration of arterial tissue in one of
+bad ancestry.</p>
+
+<p>What infectious diseases has the patient had? Even the
+exanthemata may cause degenerations in the arteries, but,
+as has been shown, such lesions probably heal completely
+with no resulting damage to the vessel. Should the patient
+have passed through a long siege of typhoid fever the problem
+is quite different. Here (vide supra) (Thayer), the
+palpable arteries do appear to be sclerosed permanently.
+Probably the length of time that the toxin has had a chance
+to act determines the permanent damage to the vessel wall.
+More potent than all other diseases to cause early arteriosclerosis
+is syphilis, and hence very careful inquiry should
+be made in regard to the possibility of infection with this
+virus. Not only the fact of actual infection but the duration
+and thoroughness of treatment are important matters
+for the physician to know.</p>
+
+<p>What is the patient's occupation? Has he been an
+athlete, particularly an oarsman? Has he been under any<span class="pagenum"><a name="Page_212" id="Page_212">[212]</a></span>
+severe, prolonged, mental strain? Is he a laborer? If so,
+in what form of manual labor is he engaged? Such questions
+as these should never be overlooked, as they form the
+foundation stones of an accurate diagnosis, and early, accurate
+diagnosis, we repeat, is essential to successful
+therapy.</p>
+
+<p>We have called attention to the factor of sustained high
+pressure in the production of arteriosclerosis. Constant
+overstretching of the vessels leads to efforts of the body to
+increase the strength of the part or parts. The material
+which is used to strengthen the weakened walls has a higher
+elastic resistance than muscle and elastic tissue, but a lower
+limit of elasticity, and is none other than the familiar connective
+tissue. In athletes, laborers, brain workers who are
+under constant mental strain, and in those whose calling
+brings them into contact with such poisons as lead, there is
+every factor necessary for the production of high tension
+and consequently of arteriosclerosis.</p>
+
+<p>Another question in regard to personal habits is how
+much tobacco does the patient use and in what form does he
+use it? Our experience is that the cigar smoker is more
+prone to present the symptoms of arteriosclerosis than the
+cigarette smoker, the pipe smoker, or the one who chews the
+tobacco. A very irritable heart results not infrequently
+from cigarette smoking but such is almost always found in
+young men in whom the lesions of arteriosclerosis are exceedingly
+rare. The probabilities are that the arteriosclerosis
+in cigar smoking results from the slowly acting poison
+which causes a rapid heart rate with an increase of pressure.</p>
+
+<p>Last but not least, and perhaps the most important question
+is, has the patient been a heavy eater? This I believe
+to be a potent cause of splanchnic arteriosclerosis with the
+resulting indigestion, cramp-like attacks, high blood pressure,
+etc. In a joking manner we are accustomed to remark,
+"Overeating is the curse of the American people."
+There is, however, much truth in that sentence. Osler, than<span class="pagenum"><a name="Page_213" id="Page_213">[213]</a></span>
+whom there is no keener observer, states that he is more
+and more impressed with the fact that overloading the
+stomach with rich or heavy or spiced foods is today one of
+the first causes of arterial degeneration. It stands to reason
+that this is true. We know that organs exposed constantly
+to hard work undergo hypertrophy, and that the
+blood tension in those organs is high. Blood tension is,
+after all, dependent on capillary resistance, and if the capillaries
+are distended with blood, the resistance is great.
+The digestive organs can be no exception to this rule. Increased
+work means an increase of blood. This inevitably
+causes distension of the capillaries with stretching of the
+arteries and consequent damage to the walls. Once arteriosclerosis
+is present a vicious circle is established.</p>
+
+<p>A man about forty-five consults us and says that he has
+noticed recently that he gets out of breath easily; in tying
+his shoes he experiences some dizziness. He finds that he
+has palpitation of the heart and possibly pain over the
+precordial region now and then. He notices also that he is
+irritable, that is, his family tell him he is, and he notices
+that things that formerly did not annoy him, now are almost
+hateful to him. On examination, one finds a palpable radial,
+a somewhat hypertrophied heart and slightly accentuated
+second aortic sound. The blood pressure may be
+high. The urine may or may not reveal any abnormalities.
+Not infrequently, although no albumin may be found, there
+are hyaline casts. Such a case of arteriosclerosis is evidently
+not to be regarded as early. Then the question
+arises, How are we to recognize early arteriosclerosis? I
+do not believe that the solution of this problem lies entirely
+in the hands of the physician. Some men are fortunate
+enough to come up for an examination for life insurance
+before an observant doctor who recognizes the palpable
+artery, makes out the beginning heart hypertrophy and the
+slightly accentuated second aortic sound. The patient will
+tell you that he never felt better in his life. He gets up at<span class="pagenum"><a name="Page_214" id="Page_214">[214]</a></span>
+seven, works all day, plays golf, drinks his three to six
+whiskies, and is proud of his physical development. But
+the great mass of people are not fortunate from this standpoint.
+They do not seek the advice of the physician until
+they are stretched out in bed. They boast of the fact that
+for twenty years they have never had a doctor. One may
+well say that it is a problem how to reach such persons. It
+seems to me that there can be but one way to do this. The
+people must be taught that the duty of a physician is just
+as much to keep them in health as it is to bring them back
+to health when they are ill. To that end people should be
+taught that at least twice a year they should be carefully
+examined. I do not mean that the patient should present
+himself to the doctor and, after a few questions the doctor
+say cheerfully, "You are all right." The patient should
+be systematically examined. That means a removal of the
+clothing and examination on the bare skin. Such cooperation
+on the part of patient and doctor would save the patient
+years of active life and make of the doctor, what his
+position entitles him to be, the benefactor to the community.
+Too often careless work on the physician's part lulls the
+patient into a false sense of security and he wakes up too
+late to find that he has wasted months or years of life.
+Early diagnosis of arteriosclerosis is only possible in exceptional
+cases unless people present themselves to the physician
+with the thought in mind that he is the guardian of
+health as well as the healer.</p>
+
+<p>There are patients who go to the ophthalmologist for
+failing vision. Physically they feel quite well. They have
+been heavy eaters, hard workers, men and women who have
+been under great mental strain. On examination of the
+fundus of the eye there is found slight tortuosity of the vessels
+with possibly areas of degeneration in the retina. A
+careful physical examination will usually reveal the signs
+of arteriosclerosis elsewhere. We have mentioned frequently
+high tension as an early sign. This must be taken<span class="pagenum"><a name="Page_215" id="Page_215">[215]</a></span>
+with somewhat of a reservation, for this reason: not infrequently
+a persistent high tension is the earliest sign of
+chronic nephritis. The arteries may be pipe stem in character
+and the heart small and flabby. However, if one
+watches for the palpably thickened superficial arteries (always
+bearing in mind the normal palpability as age advances)
+and the high tension, he can not go far wrong in his
+treatment whether the case is one of chronic nephritis or of
+arteriosclerosis.</p>
+
+<p>There is also this to bear in mind. Arteriosclerosis may
+be marked in some vessels and so slight in the peripheral
+vessels that it can not with certainty be made out. But
+when the radials are sclerosed, it is usually the case that
+similar changes exist in other parts. Then too, there may
+be marked changes at the root of the aorta leading to
+sclerosis of the coronary vessels alone, and the first intimation
+that the patient or any one else has that there is disease,
+may be an attack of angina pectoris. Except for
+symptoms on the part of the heart there is no way to make
+the diagnosis of sclerosis of the coronary arteries.</p>
+
+
+<h4>Differential Diagnosis</h4>
+
+<p>In arriving at a diagnosis, when the question is whether
+or not arteriosclerosis is the main etiologic factor, the
+most important fact to know is the age of the patient.
+Other points that have been dwelt on fully must of necessity
+also be borne in mind.</p>
+
+<p>Possibly the chief conditions that may be confused with
+some of the results of arteriosclerosis are pseudo angina
+pectoris which may be mistaken for true angina pectoris,
+and ulcer of the stomach, appendicitis (?) or other inflammatory
+abdominal condition which may be mistaken for
+angina abdominalis.</p>
+
+<p>Differential tables are sometimes of value in fixing the
+chief points of difference graphically.</p>
+
+
+<p><span class="pagenum"><a name="Page_216" id="Page_216">[216]</a></span></p>
+<p>&nbsp;</p>
+
+
+<table border="0" cellpadding="4" cellspacing="0" summary="Angina Pectoris">
+
+<tr>
+<td><b>Pseudo angina pectoris</b>.</td><td><b>True angina pectoris</b>.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td>
+</tr>
+
+
+<tr>
+<td>Etiology rather certain; hysteria,
+neurasthenia, toxic agents, and reflex
+irritations.</td><td>Etiology not certain but almost always
+associated with arteriosclerosis
+of the coronary arteries and also
+aortic regurgitation.</td></tr>
+
+<tr>
+<td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>No age is exempt. Usually in
+young people, chiefly females.</td>
+<td>Age is important factor. Rare before
+forty, and males usually affected.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Paroxysms of pain occur spontaneously,
+are periodic and often nocturnal.</td>
+<td>Paroxysms brought on by overexertions
+or excessive mental emotion.
+Rarely periodic.
+</td></tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Pain, while severe, is diffuse and
+sensation is of distension of heart.
+No sense of real anguish.</td>
+<td>Intense pain, radiating down arm;
+heart felt as in a vise. Sense of anguish
+and impending dissolution.</td></tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Duration may be an hour or more.</td>
+<td>Duration from few seconds to several
+minutes.</td></tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Restlessness and emotional symptoms
+of causative conditions are
+prominent.</td>
+<td>Silent and fixed attitude, rigidity
+rather than restlessness.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Usually no increase in arterial tension.</td>
+<td>Arterial tension is as a rule increased.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Prognosis favorable.</td>
+<td>Prognosis most unfavorable.</td>
+</tr>
+
+</table>
+<p>&nbsp;</p>
+
+<p>In differentiating between ulcer of the stomach and
+angina abdominalis the following points may be of service:</p>
+
+<p>&nbsp;</p>
+
+
+
+<table border="0" cellpadding="4" cellspacing="0" summary="Ulcer">
+<tr>
+<td><b>Ulcer</b>.</td>
+<td><b>Angina abdominalis</b>.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Occurs as a rule in young persons,
+more often females.</td>
+<td>Only occurs in adults over forty
+who have been heavy eaters and
+drinkers, mostly males.</td></tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr><td>Pain of boring character increased
+by food and by certain positions with
+food in stomach. Felt through to
+left of spine.</td>
+<td>Pain cramp-like, diffuse, although
+more localized in epigastrium. Not
+necessarily any connection with food.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Occult blood found in stools.</td>
+
+<td>
+No occult blood in stools.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr><td>Considerable anemia apt to be
+present.</td>
+<td>Anemia more often absent.</td>
+</tr>
+
+<tr>
+<td>&nbsp;</td><td>&nbsp;</td>
+</tr>
+
+<tr>
+<td>Arterial tension usually low.</td>
+<td>Arterial tension high. (Splanchnic
+sclerosis.)</td>
+</tr>
+
+</table>
+
+
+
+
+<h4>Diseases in Which Arteriosclerosis Is Commonly Found</h4>
+
+<p>There are certain more or less chronic diseases in which
+arteriosclerosis is found either as a separate disease or as
+a result of the chronic disease itself, or the sclerosis may be
+the cause of the disease. As examples of the first class
+are diabetes mellitus and cirrhosis of the liver. As examples<span class="pagenum"><a name="Page_217" id="Page_217">[217]</a></span>
+of the second class are chronic nephritis, gout, syphilis,
+and lead poisoning. Examples of the third class have already
+been fully described. Then certain rare diseases
+that have been briefly described in this chapter, viz.: Raynaud's
+disease and erythromelalgia are frequently associated
+with demonstrable arteriosclerosis.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_218" id="Page_218">[218]</a></span></p>
+<h2><a name="CHAPTER_XI" id="CHAPTER_XI"></a>CHAPTER XI.</h2>
+
+<h3>PROGNOSIS</h3>
+
+
+<p>In a disease that presents as many vagaries as arteriosclerosis,
+it is not possible to give a certain prognosis.
+Unfortunately we do not as a rule see the arteriosclerotic
+until the disease is well advanced, or even after some of the
+more serious complications have taken place. By that time
+the condition is progressive, and while the prognosis is
+grave the individual may live a number of years.</p>
+
+<p>It is fortunate for the arteriosclerotic that mild grades
+of the disease are compatible with a fairly active life. The
+disease in this stage may become arrested and the patient
+may live many years. Not only in the mild grades is this
+possible. Even patients with advanced sclerosis may enjoy
+good health provided the organs have not been so damaged
+as to render them unfit to perform their functions. The
+frequency with which we see advanced arteriosclerosis at
+the postmortem table as an accidental discovery, attests
+the truth of the foregoing statement. Yet how often does
+it happen that individuals, apparently in the best of health,
+suddenly succumb to an asthmatic or uremic attack, an
+apoplexy, cessation of the heart beat, or a rupture of the
+heart due to arteriosclerosis!</p>
+
+<p>In order to arrive at an intelligent opinion in regard to
+prognosis certain factors must be taken into consideration,
+chief of which are: the seat of the sclerosis; the probable
+stage; the existing complications; and, last and most important,
+the patient himself. The whole man must be studied
+and even then our prognosis must be most guarded.</p>
+
+<p>It is much more dangerous for the patient when the
+process is in the ascending portion of the arch of the aorta
+than when it has attacked the peripheral arteries. Here,
+at the root of the aorta, are the openings of the coronary<span class="pagenum"><a name="Page_219" id="Page_219">[219]</a></span>
+arteries and the arteries supplying the brain are close by.
+The coronary arteries here control the situation. When
+loud murmurs are heard at the aortic orifice and the heart
+is evidently diseased, it is useful to divide the endocarditis
+into two types, the arteriosclerotic and the endocarditic.
+The etiology of the former is sclerosis and the prognosis is
+grave because of the liability, nay the probability, that the
+orifices of the coronary arteries will become narrowed.
+The etiology of the second type is in most cases rheumatic
+fever or some other infectious disease, and the prognosis
+is far better than in the first type. True, the two may be
+combined. In such a case, the prognosis is entirely dependent
+upon the course of the arteriosclerosis.</p>
+
+<p>The involvement of the arteries in the kidneys is of considerable
+importance, for it is usually bilateral and widespread.
+As a rule, the disease makes but slow progress
+provided that the general condition of the patient is good,
+but at any time from a slight indiscretion or for no assignable
+cause, symptoms of renal insufficiency may appear and
+may rapidly prove fatal.</p>
+
+<p>It must not be thought that because the localization of
+the arteriosclerosis in the peripheral arteries is usually the
+most favorable condition that it is therefore devoid of ill
+effects. On the contrary, very serious, even fatal, results
+may be brought about by interference with the circulation
+with resultant extensive gangrene of the part supplied by
+the diseased arteries. The amputation of a portion of a
+leg, for instance, may relieve, to some extent, an overburdened
+heart and prove life-saving to the patient, but the
+neuritic pains are not necessarily relieved. The torture
+from these pains may be excruciating.</p>
+
+<p>No stage of the disease is exempt from its particular
+danger. In the early stages of the disease before the
+artery or arteries have had time to become strengthened by
+proliferation of the connective tissue, there is the danger of
+aneurysm. Later, the very same protective mechanism
+leads to stiffening and narrowing of the arteries and hence<span class="pagenum"><a name="Page_220" id="Page_220">[220]</a></span>
+to increased work on the part of the heart with all of its
+consequences. Thrombosis is favored, and where atheromatous
+ulcers are formed, embolism is to be feared.</p>
+
+<p>As the complications and results of arteriosclerosis come
+to the front every one must be considered by itself and as
+if it were the true disease. There may be a slight apoplectic
+attack from which the patient fully recovers, but the
+prognosis is now of a grave character, as the chances are
+that another attack may supervene and carry off the subject.
+Yet, after an apoplectic attack, patients have lived for many
+years. Probably the most noted illustration of this is the
+life of Pasteur. He had at forty-six hemiplegia with gradual
+onset. He recovered with a resulting slight limp, did
+some of his best work after the stroke, and lived to be
+seventy-three years old. Yet the exception but proves the
+rule and the prognosis after one apoplectic stroke should
+always be guarded.</p>
+
+<p>The first attack of cardiac asthma is to be looked upon
+as the beginning of the end. The end may be postponed
+for some time, but it comes nearer with every subsequent
+attack. One may recover from what appears to be a fatal
+attack of cardiac asthma accompanied by edema of the lungs
+and irregular, intermittent, laboring heart, but the recovery
+is slow and the chances that the next attack will be the
+fatal one are increased.</p>
+
+<p>The significance of albuminuria is difficult to determine.
+The kidneys secrete albumin under so many conditions that
+the mere presence of albumin in the urine may have but
+little prognostic value. Many cases are seen where there is
+no demonstrable albumin, and yet the patient may suddenly
+have a cerebral hemorrhage. As a general rule the urine
+should be carefully examined, but not too much stress should
+be laid on the discovery of albumin and casts. It is not
+always possible to determine the extent of the kidney lesion
+by the urinary examination, yet at any time a uremic attack
+may appear and prove fatal.</p>
+
+<p><span class="pagenum"><a name="Page_221" id="Page_221">[221]</a></span>After all the most important fact for the patient is not
+what the pathologist finds in his kidneys after he is dead,
+but what the living functional capacity of the kidneys is.
+This can now be determined in a variety of ways as the
+result of extensive work carried out in quite recent years.
+The simplest method of determining the functional capacity
+of the kidneys is by the injection into the muscles of the
+back of a solution containing 6 mg. of the drug phenolsulphonephthalein
+in one c.c. of fluid. This comes already
+prepared in ampules, with full directions for its employment.<a name="FNanchor_16_16" id="FNanchor_16_16"></a><a href="#Footnote_16_16" class="fnanchor">[16]</a>
+Some clinicians use indigo-carmine in place of
+phthalein. The general consensus of opinion is in favor
+of phthalein.</p>
+
+<p>The nephritic test meal carefully worked out by Mosenthal<a name="FNanchor_17_17" id="FNanchor_17_17"></a><a href="#Footnote_17_17" class="fnanchor">[17]</a>
+gives much valuable information. The determination
+of the nonprotein nitrogen or the creatinin in the blood also
+reveals the functional capacity of the kidneys.<a name="FNanchor_18_18" id="FNanchor_18_18"></a><a href="#Footnote_18_18" class="fnanchor">[18]</a></p>
+
+<p>One might say that the appearance of albumin in the
+urine of an arteriosclerotic where it had not been before,
+is a bad sign, and in making a prognosis this must be taken
+into consideration.</p>
+
+<p>Bleeding from the nose is not infrequently seen in those
+who have arteriosclerosis. It can hardly be called a dangerous
+symptom as it can always be controlled by tampons.
+There are times when epistaxis is decidedly beneficial as it
+relieves headache, dizziness, and may avert the danger of
+a hemorrhage into the brain substance. It is rare to have
+nose bleed except in cases of high tension in plethoric
+individuals. My experience has been that it has saved me
+the trouble of bleeding the patient. It is always of serious
+import in that it indicates a high degree of tension, but
+there is scarcely ever any immediate danger from the nose
+bleed itself.</p>
+
+<p>Intestinal hemorrhage is always a grave sign. As has<span class="pagenum"><a name="Page_222" id="Page_222">[222]</a></span>
+been shown, arteriosclerosis of the splanchnic vessels not
+infrequently occurs, and an embolus or thrombus may completely
+occlude the superior mesenteric artery. The
+chances of the establishment of a collateral circulation are
+small, as the arteries of the intestines are end arteries.
+Necrosis of the part follows, blood is found in the stools,
+and perforation or gangrene, or both, are apt to follow.
+There may be blocking of small branches only, leading to
+ulceration of the intestine. Under all conditions the prognosis
+is serious.</p>
+
+<p>The general condition of the patient, his build, physical
+strength, powers of recuperation, etc., must be taken into
+account in giving a prognosis. The more powerful the individual,
+the more favorable, as a rule, is the prognosis, with
+this reservation always in mind, that the greater the body
+development, the greater is the heart hypertrophy, and the
+accidents from high tension must not be overlooked. Many
+puny individuals with stiff, calcified arteries go about with
+more ease than a robust man with thickened arteries only.
+The differentiation as pointed out by Allbutt (page 186),
+is well to keep in mind in giving a prognosis. It can not be
+too strongly emphasized that it is the whole patient that we
+must consider and not any one system that at the time happens
+to be the seat of greatest trouble, and by its group of
+symptoms dominates the picture.</p>
+
+<p>It is evident from what has been said that an accurate
+prognosis in arteriosclerosis is no easy matter. Were
+arteriosclerosis a simple disease of an acute character there
+might be grounds for giving a more or less definite prognosis.
+The most that can be said is that arteriosclerosis
+is always a serious disease from the time that symptoms
+begin to make themselves known. The gravity depends altogether
+on the seat of the greatest arterial changes, and
+is necessarily greater when the seat is in the brain than
+when it is in the legs or arms.</p>
+
+<p>The attitude of the patient himself also determines to a<span class="pagenum"><a name="Page_223" id="Page_223">[223]</a></span>
+great extent the prognosis. Some men, especially those
+who have always enjoyed good health, turn a deaf ear to
+warnings and instead of ordering their lives according to
+the advice of the physician, persist in going their own way
+in the hope that the luck that has always been with them will
+continue to stand at their elbows. Neither firmness nor
+pleadings avail with some men. The only salve for the conscience
+of the physician is that he has done his best to steer
+the patient away from the shoals and breakers. In others
+who realize their condition and take advantage of the advice
+given as to the regulation of their lives, the prognosis is
+generally favorable.</p>
+
+<p>To sum up the chapter in a few words, I should say:
+Always remember that the patient is a human being; study
+his habits and character and mode of life; look at him as a
+whole; take everything into consideration, and give always
+a guarded prognosis.</p>
+
+<hr style="width: 65%;" />
+
+<p><span class="pagenum"><a name="Page_224" id="Page_224">[224]</a></span></p>
+<h2><a name="CHAPTER_XII" id="CHAPTER_XII"></a>CHAPTER XII.</h2>
+
+<h3>PROPHYLAXIS</h3>
+
+
+<p>Arteriosclerosis comes to almost every one who lives out
+his allotted time of life. As has been noted within, many
+diseases and many habits of life are conducive to the early
+appearance of arterial degeneration. Decay and degeneration
+of the tissues are necessary concomitants of advancing
+years and none of us can escape growing old. From
+the period of adolescence certain of the tissues are commencing
+a retrograde metamorphosis, and hand in hand
+with this goes the deposit of fibrous tissue which later may
+become calcified. The arterial tissue is no exception to this
+rule, and we have already shown that certain changes normally
+take place as the individual grows older, changes
+which are arteriosclerotic in type and are quite like those
+caused in younger people by many of the etiologic factors
+of the disease.</p>
+
+<p>We are absolutely dependent upon the integrity of our
+hearts and blood vessels for the maintenance of activity and
+span of life. Respiration may cease and be carried on artificially
+for many hours while the heart continues to beat.
+Even the heart has been massaged and the individual has
+been brought back to life after its pulsations have ceased,
+but such cases are few in number. We can not live without
+the heart beat and the prophylaxis of arteriosclerosis consists
+in the adjustment of our lives to our environment, so
+that we may get the maximum amount of work accomplished
+with the minimum amount of wear and tear on the blood
+vessels.</p>
+
+<p>The struggle for existence is keen. Competition in every
+profession or trade is exceedingly acute, so much so that to
+rise to the head in any branch of human activity requires<span class="pagenum"><a name="Page_225" id="Page_225">[225]</a></span>
+exceptional powers of mind. Among those who are entered
+in this keen competition, the fittest only can survive for any
+period of time. The weaklings are bound to succumb. A
+scion of healthy stock will stand the wear and tear far better
+than will the progeny of diseased parentage.</p>
+
+<p>It is only necessary to call attention to the part that
+alcohol, syphilis and insanity play in heredity. These have
+been discussed fully in the earlier part of this book.</p>
+
+<p>We live rapidly, burning the candle at both ends. It is
+not strange that so many comparatively young men and
+women grow old prematurely. While heredity is a factor
+as far as the prophylaxis of arteriosclerosis is concerned,
+of far more importance is the mode of life of the individual.
+Scarcely any of us lead strictly temperate lives. If
+we do not abuse our bodies by excessive eating and drinking
+and so wear out our splanchnic vessels and cause general
+sclerosis by the high tension thereby induced, we abuse
+our bodies by excessive brain work and worry with all their
+multitudinous evils. The prophylaxis of arteriosclerosis
+might well be labeled, "The plea for a more rational mode
+of life." Moderation in all things is the keynote to health,
+and to grow old gracefully is an art that admits of cultivation.
+Excesses of any kind, be they mental, moral, or
+physical, tend to wear out the organism.</p>
+
+<p>People habitually eat too much; many drink too much.
+They throw into the vascular system excessive fluid combined
+frequently with toxic products that cause eventually
+a condition of high arterial tension. It has been shown how
+poisonous substances absorbed from the intestines have
+some influence on the blood pressure. Anything that causes
+constant increase of pressure should be studiously avoided.</p>
+
+<p>Mild exercise is an essential feature of prophylaxis. One
+may, by judicious exercise and diet, make of himself a
+powerful muscular man without, at the same time, raising
+his average blood pressure. The man who goes to excess
+and continually overburdens his heart, will suffer the consequences,<span class="pagenum"><a name="Page_226" id="Page_226">[226]</a></span>
+for the bill with compound interest will be
+charged against him. It is a great mistake for any one to
+work incessantly with no physical relaxation of any kind,
+and yet, after all, it is not so much physical relaxation that
+is necessary, as the pursuit of something entirely different,
+so that the mind may be carried into channels other than
+the accustomed routes. Diversification of interests is as a
+rule restful. That is what every man who reaches adult
+life should aim at. Hobbies are sometimes the salvation of
+men. They may be ridden hard, but even then they are
+helpful in bearing one completely away from daily cares
+and worries. The man who can keep the balance between
+his mental and physical work is the man who will, other
+things being equal, live the longest and enjoy the best
+health.</p>
+
+<p>Nowadays the trend of medicine is toward prophylaxis.
+We give the state authority to control epidemics so far as
+it is possible by modern measures to control them.</p>
+
+<p>We urge over and over again the value of early diagnosis
+in all chronic diseases, for we know that many of them, and
+this applies particularly to arteriosclerosis, could be prevented
+from advancing by the recognition of the condition
+and the institution of proper hygienic and medicinal treatment.</p>
+
+<p><i>It is the patent duty of every physician to instruct the
+members of his clientele in the fundamental rules of health.</i>
+Recently the President of the American Medical Association,
+in his address before the 1908 meeting, urged the
+dissemination of accurate knowledge concerning diseases
+among the laity. While this may be done by city and state
+boards of health, it seems far better for the modern trained
+physician to work among his own people. With concise
+information concerning the modes of infection and the dangers
+of waiting until a disease has a firm hold before consulting
+the health mender, people should be able to protect
+themselves from infections and be able to nip chronic processes<span class="pagenum"><a name="Page_227" id="Page_227">[227]</a></span>
+in the bud. But it is difficult to turn the average
+individual away from the habit of having a drug-clerk prescribe
+a dose of medicine for the ailment that troubles him.
+It is really unfortunate that most of the pains and aches and
+morbid sensations that one has speedily pass away with
+little or no treatment. Herein lies the strength of charlatanism
+and quackery. Unfortunate, yes, for a man can not
+tell whether the trivial complaint from which he suffers is
+any different from the one that was so easily conquered six
+months ago. But instead of recovering, he grows worse.
+Hope that springs eternal in the human breast, leads him
+to dilly-dally until he at last seeks medical advice, only to
+find that the disease has made such progress that little can
+be done.</p>
+
+<p><i>Instruct the public to consult the doctors twice a year.</i>
+The dentists have their patients return to them at stated
+intervals only to see if all is well. <i>How much more rational
+it would be if men and women past the age of forty had
+a physical examination made twice a year to find out if all
+is well.</i></p>
+
+<p>The prophylaxis of arteriosclerosis is moderation in all
+the duties and pleasures of life. This in no sense means
+that a man has to nurse himself into neurasthenia for fear
+that something will happen to him. As one grows in years
+exercise should not be as violent as it was when younger,
+and food should be taken in smaller quantities. Many forms
+of exercise suggest themselves, particularly walking and
+golf. Walking is a much neglected form of exercise which,
+in these modern days with our thousand and one means of
+locomotion, is becoming almost extinct. There is no better
+form of exercise than graded walking. To strengthen the
+heart selected hill climbing is one of the best therapeutic
+methods that we have. The patient is made to exercise his
+heart just as he is made to exercise his legs, and as with
+exercise of voluntary muscles comes increase in strength,
+so by fitting exercise may the heart muscle be increased in<span class="pagenum"><a name="Page_228" id="Page_228">[228]</a></span>
+power. A warning should be sounded, however, against
+over exercise. This leads naturally to hypertrophy with
+all its disastrous possibilities. Men who have been athletes
+when young should guard against overeating and lack of
+exercise as they grow older. Many of the factors which
+favor the development of arteriosclerosis are already there,
+and a sedentary, ordinary life, such as office all day, club
+in afternoon, a few drinks and much rich food, will inevitably
+lead to well-advanced arterial disease.</p>
+
+<p>Karl Marx in his famous Socialistic platform said: "No
+rights without duties; no duties without rights." So we
+may paraphrase this and say: "No brain work without
+moderate physical exercise in the open air; no physical exercise
+without moderate brain work."</p>
+
+<p>There is yet one other point that is important, the combination
+of concentrated brain work and constant whiskey
+drinking. This is most often seen in men of forty-five to
+fifty-five, heads of large business concerns who habitually
+take from six to twelve drinks of whiskey daily, and with
+possibly a bottle of wine for dinner. Such men appear
+ruddy and in prime health but, almost invariably, careful
+examination will reveal unmistakable signs of arterial disease.
+There is usually the enlarged heart and pulse of high
+tension with or without the trace of albumin in the urine.
+The lurking danger of this group of manifestations has so
+impressed the medical directors of several of the large insurance
+companies that a blood pressure reading must be
+made on all applicants over forty years of age. Should high
+blood pressure be found, the premium is increased, as the
+expectation of life is proportionately shorter in such men
+than in normal persons.</p>
+
+<p>Therefore, let every physician act his part as guardian
+of health. Only in this way is the prophylaxis of arteriosclerosis
+possible.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_229" id="Page_229">[229]</a></span></p>
+<h2><a name="CHAPTER_XIII" id="CHAPTER_XIII"></a>CHAPTER XIII.</h2>
+
+<h3>TREATMENT</h3>
+
+
+<p>Although it has been rather dogmatically stated (vide
+supra) that every one who reaches old age has arteriosclerosis,
+it must not be inferred that absolutely no exceptions to
+this rule are found. Cases are known where persons of
+ninety years even had soft arteries, and we have seen persons
+of eighty whose arteries could not be palpated. When
+infants and children are seen with considerable sclerosis,
+it proves that, after all, it is the quality of the tissue even
+more than the wear and tear, that is the determining factor
+in the production of arteriosclerosis. It would be well if
+those who can not bring healthy progeny into the world
+were to leave this duty to those who can.</p>
+
+<p>In general the treatment of arteriosclerosis is prophylactic
+and symptomatic. In the preceding chapter I had something
+to say about prophylaxis in general; I must again
+refer to it in detail.</p>
+
+<p>Arteriosclerosis is essentially a chronic progressive disease,
+and the secret of success in the management of it is
+not to treat the disease or the stage of the disease, but to
+treat the patient who has the disease. To infer the stage
+of the disease from the feeling of the sclerosed artery, may
+lead to serious mistakes. Persons with calcified arteries
+may be perfectly comfortable, while those with only moderate
+thickening may have many severe symptoms. The
+keynote is individualization. It is manifestly absurd to
+treat the laboring man with his arteriosclerosis as one
+would treat the successful financier. The habits, mode of
+life, every detail, should be studied in every patient if we
+expect to gain the greatest measure of success in the treatment.
+One may treat fifty patients who have typhoid fever<span class="pagenum"><a name="Page_230" id="Page_230">[230]</a></span>
+by a routine method and all may recover. Individualizing,
+while of great value in the treatment of acute diseases, yet
+is not absolutely essential in order that good results may
+be obtained. Far different is it when treating a disease
+like arteriosclerosis. One who relies on textbook knowledge
+will find himself at a loss to know what to do. Textbooks
+can only outline, in the briefest manner, the average
+case, and no one ever sees the average book case. At the
+bedside with the patients is the place to learn therapeutics
+as well as diagnosis. All that can be hoped for in outlining
+the treatment of arteriosclerosis is to lay down a few principles.
+The tact, the intuition, the subtle something that
+makes the successful therapeutist, can not be learned from
+books. So the man who treats cases by rule of thumb is a
+failure from the beginning. There are certain general
+principles that will be our sheet anchors at all times and
+for all cases. The art of varying the application of these
+fundamentals to suit the individual case, is not to be culled
+from printed words.</p>
+
+
+<h4>Hygienic Treatment</h4>
+
+<p>Every man is more or less the arbiter of his own fate.
+Granted that he has good tissue to begin life, his own habits
+and actions determine his span of comfortable existence.
+No one cares to live after his brain begins to fail, and the
+failing brain is often due to disease of the cranial arteries.
+The hygienic treatment resolves itself into advice in regard
+to prophylaxis.</p>
+
+<p>First and foremost is exercise. It has seemed to us that
+the revival of out-of-door sports is one of the best signs of
+promise of the preservation of a virile, hardy race. That
+women, as well as men, indulge in the lighter forms of out-of-door
+exercise should bring it about that the coming
+generation will start in life under the most advantageous
+conditions of bodily resistance.</p>
+
+<p>Among all the forms of exercise, golf probably is the best.<span class="pagenum"><a name="Page_231" id="Page_231">[231]</a></span>
+It is not too violent for the middle-aged man, yet it gives
+the young athlete quite enough exercise to tire him. It is
+played in the open. One is compelled to walk up and down
+in pleasant company, for golf is essentially a companionable
+game, while he reaps the full benefit of the invigorating exercise.
+The blood courses through the muscles and lungs
+more rapidly; the contraction of the skeletal muscles serves
+to compress the veins and so to aid the return of blood to
+the heart: the lungs are rendered hyperemic, deeper and
+fuller breaths must be taken; oxidation is necessarily more
+rapid, and effete products, which if not completely oxidized
+would possibly act as vasoconstrictors, are oxidized to
+harmless products and eliminated without irritating the
+excretory organs.</p>
+
+<p>Other forms of out-door exercise that can be recommended
+are tennis, canoeing, rowing, fishing, horseback riding,
+swimming, etc. Tennis is the most violent of all the
+sports mentioned and might readily be overdone. Rowing
+as practiced by the eights at college is undoubtedly too violent
+a form of exercise, and may be productive in later life
+of very grave results. Canoeing is a delightful and invigorating
+exercise. The muscles of the arms, shoulders,
+and trunk are especially used, the leg muscles scarcely at
+all. Nevertheless, the deep breathing that necessarily
+comes with all chest exercises aerates every portion of the
+lungs, and is of great benefit to the whole body.</p>
+
+<p>Swimming as an exercise has much to recommend it. In
+this sport all the muscles take part and at the same time the
+chest is broadened and deepened.</p>
+
+<p>All these methods of using the muscles to keep oneself in
+trim, so to speak, are part and parcel of the general hygienic
+mode of life that is conducive to a healthy old age. Exercise
+can be overdone, as eating can be overdone. Both are
+essential and yet both can be the means of hastening an individual
+to a premature grave.</p>
+
+<p>When the arteriosclerosis has advanced so far that it is<span class="pagenum"><a name="Page_232" id="Page_232">[232]</a></span>
+easily recognizable, certain forms of exercise should be absolutely
+prohibited. Such are tennis, rowing and swimming.
+Horseback riding to be allowed must be strictly supervised.
+At times this may be an exceedingly violent exercise. As
+an out-of-door sport, there is nothing that equals golf.
+The physician, knowing the character of the course, and
+the length of it, can say to his patient that he may play six,
+nine, twelve, or eighteen holes, depending on the patient's
+condition.</p>
+
+<p>For those who are not able to get out, exercise in the
+room with the windows open must take the place of out-of-door
+sports. Here the use of chest weights is a most
+excellent means of keeping up the tone of the muscles. By
+adjusting the weights, the exercise may be made light,
+medium, or heavy. Every physician should be familiar
+with the chest weight exercises. They are not as good as
+open air exercise but they undoubtedly have been the means
+of saving years of life to many patients with arterial
+disease.</p>
+
+<p>There comes a time when all forms of exercise must be
+prohibited on account of the dyspnea, edema, dizziness, etc.
+It seems unwise to keep such a patient in bed, even though
+the edema be considerable. Once on his back in bed he
+becomes weak, and the danger of edema of the lungs or
+hypostatic congestion of the bases, with subsequent bronchopneumonia,
+is very great.</p>
+
+<p>Such patients may be allowed to sit up in a comfortable
+chair with the legs supported straight out on a stool or
+other chair. The half reclining position is not easy to assume
+in bed. Considerable ingenuity must often be exercised
+by the physician in making the patient comfortable
+without increasing the symptoms from which the patient
+suffers following the least amount of exercise. Although
+such persons can not exercise actively, they should have
+passive exercise in the form of massage, carefully given, so
+that no injury is done to the rigid vessels. It is possible to<span class="pagenum"><a name="Page_233" id="Page_233">[233]</a></span>
+rupture a vessel, the walls of which are encrusted with lime
+salts, and full of small aneurysmal dilatations. Every patient
+must be watched carefully and measures instituted for
+the individual.</p>
+
+
+<h4>Balneotherapy</h4>
+
+<p>As a tonic and invigorator, the cold or cool bath (shower
+or tub), in the morning on arising can be highly recommended.
+It promotes skin activity, is a stimulant to the
+bowels and kidneys and to the general circulation, besides
+being cleansing. We find today that the morning bath has
+become such a necessity to the average American that all
+new hotels are fitted with private baths, and old hotels, in
+order to get patronage, are arranging as many baths connected
+with sleeping rooms as is possible. Our generation
+assuredly is a ruddy, clean-bodied one. What the actual
+results of this out-door life and frequent bathing will be
+for the race remains to be seen, but one can not but feel
+that it must build up a stronger, more resistant race of
+people, who not only enjoy better health than did their forefathers,
+but enjoy it longer.</p>
+
+<p>Not every one can stand a cold bath. It is folly to urge
+it on one to whom it is distasteful, or on one who does not
+feel the comfortable glow that should naturally result. For
+the well, or those with a tendency to arteriosclerosis, or
+those in whose families there have been several members
+who had early arteriosclerosis, such proceedings as recommended
+could not be improved upon. However, for the
+person who has well recognized sclerosis, only warm baths
+should be advised, and these not daily. The water should
+be at a temperature of 90-95° F. Care should be taken
+that persons sent to spas be cautioned against hot baths.
+It is not inconceivable that the increased force of the heart
+beat that accompanies a hot bath might be sufficient to rupture
+a small cranial vessel. Hence, Turkish and Russian
+baths should be most unqualifiedly condemned. As a matter<span class="pagenum"><a name="Page_234" id="Page_234">[234]</a></span>
+of fact, persons vary so in their habits with regard to
+bathing that what might suit one person would do another
+much harm.</p>
+
+
+<h4>Personal Habits</h4>
+
+<p>The personal habits of the individual, more than any
+other factor, determine whether or not arteriosclerosis sets
+in early in his life. The man or woman who is moderate in
+eating and drinking, sees that the kidneys are kept in good
+condition, and attends strictly to regularity of the bowels,
+lays a good basis for the measure of health which is so
+essential for happiness. It has been shown that sclerosis
+of the splanchnic vessels may be due to constant irritation
+of toxic products elaborated in digesting constantly enormous
+meals. In obstinate constipation, many poisons, the
+nature of which we do not know, are absorbed and circulate
+in the blood. We have not sufficient data to prove that
+constipation favors the production of arteriosclerosis, but
+our impression has been that it does favor it. Constipation
+can often be relieved by a glass of water before breakfast,
+a regular time to go to stool, and abdominal massage
+or exercises. Some maintain that it is a bad habit only,
+and can be readily overcome. Whatever is done, avoid
+leading the patient into the drug habit, for the last state
+of the patient will be worse than the first. Habits of sleep
+are not of such great importance. Most persons get enough
+sleep except when under severe mental strain. Most adults
+need from seven to eight hours' sleep, although some can
+do all their work and keep in prime health on five or six
+hours' sleep.</p>
+
+<p>Tobacco has been accused of causing many ills and has
+been thereby much maligned. We can not see that the use
+of tobacco in any form in moderation is harmful to most
+men. Undoubtedly the blood pressure is raised when mild
+tobacco poisoning occurs, and individual peculiarities of reaction
+to the weed are multitudinous. But to condemn offhand<span class="pagenum"><a name="Page_235" id="Page_235">[235]</a></span>
+its use is the height of folly. There is no reason why
+the arteriosclerotic who has always used tobacco in moderation,
+should not continue to use it, whether he smoke cigarettes,
+cigars, or pipe. His supply should be decreased, but
+there is no sense in depriving a man of one of the solaces of
+life, unless, as is sometimes the case, abstinence is easier
+for the patient than moderation.</p>
+
+<p>As for alcohol, opinions differ widely.<a name="FNanchor_19_19" id="FNanchor_19_19"></a><a href="#Footnote_19_19" class="fnanchor">[19]</a> Some see in alcohol
+one of the most frequent causes of arteriosclerosis;
+others do not believe that the part played by alcohol is a
+serious one, only in conjunction with other poisonous substances
+is it dangerous. Probably unreasoning fanaticism
+has had much to do with the wholesale condemnation of
+alcoholic beverages. The general effect of alcohol is to
+lower the blood pressure by causing marked dilatation of
+all the vessels of the skin. True, the alcohol circulates in
+the blood, and is broken up in the liver, and this organ
+would seem to bear the brunt of the harm done. Alcoholic
+drinks in moderation, I do not believe have any deleterious
+effect on health. On the contrary, I believe that they may
+in some cases assist digestion and assimilation. Indiscriminate
+indulgence is to be condemned, as is overindulgence
+in exercise or eating. What may be moderate for A, might
+be excessive for B. Every man is then the arbiter of his
+own fortune and within his own limits can indulge moderately
+(a relative term after all) without fear of doing himself
+harm. In advanced arteriosclerosis it is necessary to
+decrease the supply of alcohol just as it is necessary to cut
+down the food supply. This must rest entirely on the
+judgment of the physician, who must not act arbitrarily,
+but must have his reasons for every one of his orders.</p>
+
+<h4>Dietetic Treatment</h4>
+
+<p>Most persons eat too much. We not only satisfy our
+hunger, but we satisfy our palates, and, instead of putting<span class="pagenum"><a name="Page_236" id="Page_236">[236]</a></span>
+substantial foodstuffs into our stomachs, we frequently take
+unto ourselves concoctions that defy description.</p>
+
+<p>Foodstuffs are composed of one or all of three classes:
+(1) proteins, (2) fats, (3) carbohydrates. As examples
+of the first are beef and white of egg; of the second, the
+oils, butter, lard; of the third, sugar, potato, beet, corn, etc.</p>
+
+<p>The physiologists and chemists have shown us that both
+endogenous and exogenous uric acid in excess will cause a
+rise of blood pressure, but the bodies most concerned in
+the production of elevated blood pressure are the purin
+bodies, those organic compounds which are formed from
+proteins and represent chemically a step in the oxidation
+of part of the protein molecule to uric acid. Red meat
+contains more of the substances producing purin bodies
+than any other one common foodstuff, and for this reason
+the excessive meat eater is, <i>ceteris paribus</i>, more apt to
+develop arteriosclerosis comparatively early in life.</p>
+
+<p>The fats and carbohydrates contain practically no substances
+that react on the body of the ordinary individual
+in a deleterious manner during their digestion. The extra
+work that is put on the heart by the formation of many
+new blood vessels in adipose tissue is the only harmful effect
+of overindulgence in these foodstuffs.</p>
+
+<p>It has been found that nitrogen equilibrium can be maintained
+at a wide range of levels. Formerly 135-150 gms.
+of protein daily were considered necessary for a man doing
+light work. Now it is known that half that amount is sufficient
+to keep one in nitrogenous equilibrium, and to enable
+one to keep his weight. A person at rest requires even less
+than that. One who is engaged in hard physical labor burns
+up more fuel in the muscles, and so must have a larger
+fuel supply.</p>
+
+<p>Although we habitually eat too much we drink too little
+water. For those who have any form of arterial disease
+an excess of fluid is harmful, as the vessels become filled
+up and a condition of plethora results, which necessarily<span class="pagenum"><a name="Page_237" id="Page_237">[237]</a></span>
+reacts injuriously on the heart and circulation. The drinking
+of a glass of water during meals is, in the author's
+opinion, good practice. The water must be taken mouthful
+at a time, and not gulped down. If this is done, there
+results sufficient dilution of the solid food to enable the
+gastric juices successfully and rapidly to reach all parts
+of the meal.</p>
+
+<p>Some are in favor of a rigid milk diet for those who
+have arteriosclerosis. Some men have lived on nothing
+but milk for several years and have not only kept in good
+health, but have actually gained weight and led at the
+same time active lives. It has been held by others that rigid
+milk diet is positively harmful on account of the relatively
+large quantity of calcium salts that are ingested. This was
+thought to favor the deposition of calcareous material in
+the walls of the already diseased arteries. While possibly
+there may be some danger of increased calcification, the
+majority of clinicians are in favor of a milk cure given at
+intervals. Thus the patient is made to take three to
+four quarts daily for a period of a month. There is then a
+gradual return to a general diet, exclusive of meat, for
+several weeks, then another rigid milk diet period.</p>
+
+<p>If we are bold enough to follow Metschnikoff in his theories
+of longevity, we might advise resection of the large
+intestine, on the ground that it is an enormous culture tube
+that produces prodigious amounts of poisonous substances
+which are thrown into the general circulation. To combat
+such a grave (?) condition as the carrying of several feet
+of large intestine, we are recommended to take buttermilk
+or milk soured by means of the <i>b. acidus lacticus</i>. Clinical
+experience has taught that in arteriosclerosis buttermilk
+is of great value, whether it be the natural product, or made
+directly from sweet milk by the addition of the bacilli. The
+latter is a smoother product and has, to my mind, a delightful
+flavor. It may be diluted with Vichy or plain soda
+water. Cases that can not take milk or any other food will<span class="pagenum"><a name="Page_238" id="Page_238">[238]</a></span>
+often take buttermilk, and do well on this restricted diet.
+From two to four quarts daily should be taken. It should
+be drunk slowly as should milk.</p>
+
+
+<h4>Medicinal</h4>
+
+<p>It has long been thought that the iodides have some specific
+effect on the advancing arteriosclerosis, checking its
+spread, if not really aiding nature to a limited restoration
+of the diseased arteries. It is possible that the eulogies
+upon the iodides owe their origin to the successful treatment
+of syphilitic arteriosclerosis, in which condition these
+drugs have a specific action. However that may be, there
+is no doubt that the administration of sodium or potassium
+iodide is good therapeutics in cases of arteriosclerosis.</p>
+
+<p>Unfortunately many persons have such irritable stomachs
+that they can not take the iodides, even though they be
+diluted many times. They may be made less irritating by
+giving them with essence of pepsin. Unless the case is
+syphilitic, it is doubtful whether it is of value to increase the
+dose gradually until a dram or even more is taken three
+times daily after meals. Usually a maximum dose of ten
+grains seems to be quite sufficient. This may be taken three
+times a day, well diluted, for three months. There follows
+a month's rest, then the treatment is resumed for another
+period of three months, and so on. Either sodium or potassium
+iodide in saturated solution may be given. The sodium
+salt is possibly less irritating, and contains more free
+iodine than the potassium salt, although the latter is more
+generally used. The strontium iodide may also be used.</p>
+
+<p>One sees a patient now and then who can not take the
+iodides, however they may be combined. For such patients
+one may obtain good results with iodopin, sajodin, or other
+of the preparations put up by reputable firms. Personally I
+have never yet seen a patient who could not take the ordinary
+iodides in some form or other, and I am opposed to
+ready made drugging.</p>
+
+<p><span class="pagenum"><a name="Page_239" id="Page_239">[239]</a></span>The action of the iodides is to lower the blood pressure,
+and they are of greatest value when the blood pressure
+is high, and when headache and precordial pain are present.</p>
+
+<p>When the case is moderately advanced, very mild doses,
+gr. &frac12;, morning and evening, of the thyroid extract may be
+given. It is generally believed that the internal secretion
+of the thyroid and the adrenal are antagonistic. That the
+thyroid secretion lowers blood pressure in certain forms of
+hypertension is certain, possibly on account of its iodine
+content. Some combinations of iodine and thyroid such as
+the iodothyroidin have been used and have had some measure
+of success attributed to them.</p>
+
+<p>Hypertension does not always demand active measures
+for its reduction. Viewed from the physiologic standpoint,
+hypertension is but the expression of a compensating
+mechanism which is designed to keep the blood moving
+through narrowed channels. Heart hypertrophy then is
+absolutely essential to the maintenance of life. It has been
+said that the highest blood pressures occur in chronic disease
+of the kidneys. The poisonous substances produced
+in the kidneys must exert their action through absorption
+into the general blood stream. This toxin may be completely
+eliminated, if we accept as our criterion the reduction
+of tension to normal together with the complete return
+of the affected individual to health. A concrete example
+is as follows: A man aged 44 years was brought to the
+Milwaukee County Hospital in coma. His systolic blood
+pressure was over 280 mm. Hg, diastolic 170 mm., his urine
+contained considerable albumin and many casts. He had
+general anasarca. Venesection was done at once and 300
+c.c. blood obtained. Immediately following this operation
+the pressure was 210-150, but within twelve hours it was
+again above 280-170. He was given no medication to reduce
+pressure except that he was freely purged. He was
+given a steam sweat bath daily. Frequent blood pressure
+readings were taken. Within seven days the pressure was<span class="pagenum"><a name="Page_240" id="Page_240">[240]</a></span>
+130-86. He had, in the meantime, completely recovered
+from his symptoms. He was kept in the hospital for two
+weeks longer assisting in the work on the ward, and he was
+discharged with a pressure (systolic) between 130 and 136
+diastolic 80-84. The treatment was rest in bed, free purging,
+venesection, and sweat baths, simple but exceedingly
+effective.</p>
+
+<p>Should there be actual indications for reducing the blood
+pressure, I must admit that it can not always be done. The
+majority of cases will do well on the sodium nitrite or
+erythrol tetranitrate. However, these do not always lower
+blood pressure and keep it within normal limits. When a
+man has very high tension we do not wish to reduce it to
+what it should normally be for the age of the patient, as
+symptoms of collapse might set in at any time under such
+conditions.</p>
+
+<p>Observations made with the sphygmomanometer<a name="FNanchor_20_20" id="FNanchor_20_20"></a><a href="#Footnote_20_20" class="fnanchor">[20]</a> show
+that the effect of nitroglycerin is transient or of no effect
+except in doses which are relatively enormous (one drop of
+the one per cent solution given every hour). Sodium nitrite
+may lower the blood pressure but the effects will have
+worn off in two hours. It is the same with erythrol tetranitrate.
+Sodium sulphocyanate in doses of from one to three
+grains three times a day is highly recommended by some.
+My own experience with it does not lead me to believe that it
+is of any great value in hypertension. It, however, may be
+tried. Benzyl benzoate has been used recently to reduce
+the high blood pressure of hypertension. Macht has reported
+some success. In the author's hands it has been
+efficacious in a few cases. As long as the patient takes the
+drug the pressure may be slightly reduced, but upon the
+withdrawal of the drug the pressure returns to its former
+level. It is well worth a trial and further experimentation<span class="pagenum"><a name="Page_241" id="Page_241">[241]</a></span>
+may reveal better methods of administration. The dose is
+from 2 to 6 c.c. mixed with water at intervals.</p>
+
+<p>In the hypertension of the menopause some have had
+success with large doses of corpus luteum extract. As
+a matter of fact the drug treatment of hypertension,
+when it becomes necessary to treat this condition with
+drugs, has suffered a notable set-back since more careful
+control has been made with the blood pressure instruments.
+In giving any of the depressor drugs their action should
+be controlled by blood pressure measurements, for only
+in this way can we be sure that the drug is exerting its
+physiological effect and we may expect results. The individual
+reaction to these drugs varies greatly and no rule
+for dosage can be dogmatically laid down. The only successful
+therapy is rigid individualization. This is the keystone
+to treatment in cases of arteriosclerosis and high
+tension.</p>
+
+<p>It must not be inferred from what has been said that the
+nitrites are of no value. They are of decided value but
+they have their limitations. The most evanescent of these
+drugs is amyl nitrite. This is put up in the form of capsules,
+or pearls, containing from one to three minims. When
+it is desired to dilate the peripheral vessels suddenly, one
+or two of these capsules are broken in a cloth held to the
+nose. The effect is almost instantaneous. There is flushing
+of the face and other peripheral vessels, particularly
+near the head, denoting a relaxation and widening of the
+bed of the blood stream, and a consequent decrease in pressure
+in the arteries. These effects are over in a short
+while. It is only used in attacks of cardiac spasm, as in
+angina pectoris. Nitroglycerin, the Spiritus Glonoini of
+the U. S. P., acts in about the same manner as amyl nitrite
+but the effects last usually a trifle longer. One drop
+of the one per cent solution may be given every hour until
+physiologic effects are produced. It may be given hypodermically.
+This may be a means of reducing pronounced<span class="pagenum"><a name="Page_242" id="Page_242">[242]</a></span>
+high tension. This drug has been found of benefit especially
+in cases where arteriosclerosis combined with chronic
+nephritis causes cardiac asthma. The other drug which
+may be of service in these conditions, one whose sphere
+of action is somewhat broader, because its effects are more
+lasting, is sodium nitrite. This is given in water in doses
+of one to three or five grains every four hours. Some
+have objected to the use of this drug, but my experience
+has made me place considerable confidence in its harmlessness,
+provided that the patient is carefully watched. This,
+however, applies to all of the nitrite compounds. My experience
+with erythrol tetranitrate is not large. It may
+be used in place of sodium nitrite.</p>
+
+<p>For a mild case, one often finds that sweet spirits of
+niter is sufficient to control the pressure and relieve the
+distressing symptoms, and it is undoubtedly the least harmful
+of all the nitrites. Drugs that are of great value, but
+of which little is noted in textbooks, are aconite and veratrum
+viride. Both of these drugs are well known to be
+marked circulatory depressors. Veratrum viride in my experience
+should be very cautiously used, and never used
+unless a trained attendant is constantly at hand. With regard
+to aconite I have no such feeling, and a mixture of
+tincture of aconite and spiritus etheris nitrosi may be
+given for several weeks with no fear of doing any harm.
+Personally, of all the drugs mentioned, I prefer the nitrite
+of sodium or the combination just given. They may be advantageously
+alternated.</p>
+
+<p>My own feeling is that the most successful means of treatment
+of acute high tension is without the use of drugs.
+The most important measure is absolute rest in bed. This
+often suffices to lower the blood pressure and to arrest the
+symptoms produced by high tension. Venesection I believe
+is also of value. True the arterioles appear to contract
+almost immediately upon the lessened quantity of blood,
+or there is immediate interchange of serum from the tissues<span class="pagenum"><a name="Page_243" id="Page_243">[243]</a></span>
+which brings the blood volume back to the original amount.
+Whatever happens the pressure is not greatly reduced, at
+times not reduced at all, but often the symptoms are relieved.
+Hot packs or sweat baths assuredly do reduce the
+pressure in many cases. This seems to me to be an exceedingly
+valuable measure. Finally the diet should be
+nourishing, but very light, not too much fluid should be
+ingested, and the bowels should be freely opened.</p>
+
+<p>With the fibrolysin of Merck, I have had no experience.
+Some men assert that they have had good results from
+its use, but on the whole the evidence is not highly favorable.</p>
+
+<p>Morphine is invaluable. No drug is of such value in the
+nocturnal dyspneic attacks that occur in the late stages of
+arteriosclerosis when the heart or the kidneys are failing.
+Morphine not only relaxes spasm and quiets the cerebral
+centers, but is an actual heart stimulant under such conditions,
+and should never be withheld, as the danger of the
+patient's becoming addicted to its use is more fanciful than
+real. However, morphine, at times, suppresses the secretion
+of urine. So that if after trial the urine becomes
+scanty and the edema increases, recourse must be had to
+other drugs. The various hypnotics may be used with
+caution. One which seems to be very useful is adalin.</p>
+
+<p>As heart stimulants, one may use strychnine, spartein,
+caffein, or camphor. In desperate cases, where a rapidly
+diffusible stimulant is needed, a hypodermic syringeful of
+ether may be given, and repeated in a short while.</p>
+
+<p>Several years ago a so-called serum was brought out by
+Trunecek which was said to have a favorable effect on the
+metabolism of the vessel walls. It was given at first hypodermatically
+or intravenously but the former method was
+painful. It was later stated that given by mouth it acted
+just as well. The results with the Trunecek serum have not
+come up to the expectations that the early favorable reports
+promised. The original serum was composed as follows:<span class="pagenum"><a name="Page_244" id="Page_244">[244]</a></span>
+NaCl, 4.92 gm.; Na<sub>2</sub>SO<sub>4</sub>, 0.44 gm.; Na<sub>2</sub>CO<sub>3</sub>, 0.21 gm.;
+K<sub>2</sub>SO<sub>4</sub>, 0.40 gm.; aqua destil. q. s. ad. 100.0 c.c. Later
+this was modified for internal use to the following prescription:</p>
+
+<p>
+&#8478;<span style="margin-left: 2em;">&nbsp; Natrii chlor. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; 10.&nbsp;&nbsp; &nbsp; gm.</span><br />
+<span style="margin-left: 3em;">Natrii sulphat.&nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;1.&nbsp;&nbsp; &nbsp; gm.</span><br />
+<span style="margin-left: 3em;">Natrii carbonat.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;0.40 gm.</span><br />
+<span style="margin-left: 3em;">Natrii phosphat.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;0.30 gm.</span><br />
+<span style="margin-left: 3em;">Calcii phosphat.</span><br />
+<span style="margin-left: 3em;">Magnesii phosphat. aa.&nbsp; 0.75 gm.</span><br />
+M. Ft. cachets No. XIII.
+</p>
+
+<p>The contents of every cachet corresponds to 15 c.c. of the
+fluid serum or to 150 c.c. of blood serum. The preparation
+called antisclerosin consists of the salts contained in the
+serum. As to its efficacy, I can not judge, as I have never
+felt that it was worth while to use it. Reports of cases in
+which it has been tried do not speak very highly of it.</p>
+
+<p>In the general treatment of arteriosclerosis, there is no
+one factor of more importance than the regular daily bowel
+movement. Attention to this may save the patient much
+discomfort and even acute attacks of cardiac embarrassment.
+The choice of the purgative is immaterial, with this
+reservation only, that the mild ones, such as cascara, rhubarb,
+licorice powder and the mineral waters, should be
+thoroughly tried before we resort to the more drastic purgatives.
+Plenolphthalein in 3 to 5 grain doses acts remarkably
+well in some people as a pleasant laxative. Agar-agar
+with or without cascara may be useful.</p>
+
+<p>Liquid paraffin under a variety of names is a most useful
+and efficacious laxative. As its action is purely mechanical
+it may be taken indefinitely without doing harm to the intestinal
+musculature.</p>
+
+<p>The old Lady Webster dinner pill is an excellent tonic
+aperient. When the heart is embarrassed and edema of the
+legs and effusion into the serous cavities have taken place,
+then it becomes necessary to use the drastic purgatives
+that cause a number of watery movements. Epsom salts<span class="pagenum"><a name="Page_245" id="Page_245">[245]</a></span>
+given in concentrated form, elaterin gr. 1-12, the compound
+cathartic pill, blue mass and scammony, or even croton
+oil may be used. Since the observation of a greatly congested
+intestine from a patient who had been given croton
+oil, I have ceased to use this purgative, and I doubt much
+whether its use is ever justifiable in these cases.</p>
+
+<p>The management of the ordinary case of arteriosclerosis
+resolves itself into a careful hygienic and dietetic regime
+with the addition of the iodides, aconite, or the nitrites.
+A diet consisting of very little meat, alcohol in moderation
+or even absolutely prohibited, and not too much fluid should
+be prescribed. Condiments and spices should also be used
+sparingly. Cold baths, shower baths, cold and hot sheets
+alternating, are of great benefit in assisting the heart to do
+its best work by making the large capillary area of the skin
+more permeable. It is not true that such baths raise the
+blood pressure so markedly. Certain acts, as sneezing, violent
+coughing, etc., increase the blood pressure much more
+than judicious bathing.</p>
+
+
+<h4>Symptomatic Treatment</h4>
+
+<p>The fact that arteriosclerosis really loses much of its own
+identity and, in later stages, becomes merged with the symptomatology
+of the diseases of various organs, as the kidney,
+brain, heart, compels us, for completeness' sake, to say a
+few words about the treatment of these complications.</p>
+
+<p>One of the results of arteriosclerosis of the coronary
+arteries, angina pectoris, demands prompt treatment. In
+the acute attack, the chief object is to relieve the spasm and
+pain. Pearls of amyl nitrite should be inhaled, and morphine
+sulphate with atropine sulphate given hypodermatically
+at the very earliest moment. It is senseless to withhold
+morphine. The only possible reason for withholding
+it would be uncertainty as to the diagnosis. It is probably
+better to err on the safe side, and should the case prove to<span class="pagenum"><a name="Page_246" id="Page_246">[246]</a></span>
+be one of pseudo angina, in the next attack sterile water
+can be given instead of the morphine and atropine.</p>
+
+<p>When a patient is seen in the condition of broken compensation
+with the much dilated heart, anasarca, dyspnea
+and suppression of urine, there is no better practice than
+venesection. Especially is this valuable when the tension is
+still fairly high and the individual is robust. Following the
+abstraction of six to eight ounces of blood (300-500 c.c.)<a name="FNanchor_21_21" id="FNanchor_21_21"></a><a href="#Footnote_21_21" class="fnanchor">[21]</a>
+the whole picture changes, so that a man who a short while
+before was apparently at death's door, notices his surroundings
+and takes an interest again in life. This should be followed
+up with thorough purgation, and cardiac stimulants
+should be ordered. In such cases digitalis is useful, but its
+action is never so striking as in cases of this general character
+due to uncompensated valvular disease. It must be remembered
+that in arteriosclerosis the changes in the myocardium
+must be of a considerable grade for the heart to
+give away. Therefore, digitalis can not be expected to act
+on a diseased muscle as it acts on a comparatively healthy
+muscle. It is only in such cases of broken compensation
+that digitalis should ever be used.</p>
+
+<p>Digitalis is not a general vasoconstrictor as used to be
+taught. Its action on the kidney is actually a vasodilator
+one. And in its action on the heart the digitonin dilates
+the coronary arteries, according to Macht, while the digitoxin
+acts on the heart muscle. Overdosing with digitalis
+has produced partial heart block in many cases. It is absolutely
+contraindicated in Stokes-Adams syndrome.</p>
+
+<p>There are, however, some cases, especially those with
+transudations, when digitalis may be carefully tried even
+though high tension be present. It is sometimes of advantage
+to combine digitalis with the nitrites although they are
+said to be physiologically incompatible.</p>
+
+<p>Still another drug, that is of great value in conditions such
+as have been described, is diuretin. This may be given in
+capsule or tablets, grs. x. three times daily. There is only<span class="pagenum"><a name="Page_247" id="Page_247">[247]</a></span>
+one caution to express in the use of this drug. It should not
+be given when the kidneys are the seat of chronic inflammatory
+changes; in fact, actual harm may be done by administering
+the drug under such conditions.</p>
+
+<p>The same is true even to a greater extent with theocin.
+This is a powerful diuretic. If given by mouth it should be
+well diluted as it is most irritating to the stomach. It is
+best given intravenously in doses of two and a half to
+three grains dissolved in five to six cubic centimeters of
+distilled water. One must be reasonably sure that the kidneys
+are not the subject of chronic disease and are functionally,
+therefore, below par. The intravenous dose should
+not be given oftener than once in four days.</p>
+
+<p>For the pain in aneurysm, nothing (except, of course,
+morphine) is so valuable as iodide of potassium. Patients
+who are suffering agony, when put to bed and given KI
+grs. x. three times a day, soon lose all the distressing symptoms.
+This applies particularly to aneurysms of the arch
+of the aorta.</p>
+
+<p>When the sclerosis has affected the cerebral arteries to
+such an extent that symptoms result, the case is, as a rule,
+exceedingly grave. Not much can be done except to relieve
+the headaches and keep down the blood pressure, if this is
+high, by means of rest in bed, the iodides, aconite, or the
+nitrites. The cases of transient monoplegias or hemiplegias
+can be much relieved by careful hygienic measures and judicious
+administration of drugs. Much ingenuity is sometimes
+required to overcome the idiosyncrasies of patients,
+but care and patience will succeed in surmounting all such
+difficulties.</p>
+
+<p>The treatment of intermittent claudication is the treatment
+of arteriosclerosis in general. Sometimes the circulation
+in the affected leg or legs is much helped by daily warm
+foot baths. Light massage might be tried and the galvanic
+current may be used once or twice daily.</p>
+
+<p><span class="pagenum"><a name="Page_248" id="Page_248">[248]</a></span>There are a few distressing symptoms that occur usually
+late in the disease, when complications have already occurred,
+which frequently baffle the therapeutic skill of the
+physician. The chief of these&mdash;insomnia, dyspnea, and
+headache&mdash;may not be late manifestations, but insomnia and
+headache are frequently associated with the moderately
+advanced stages of arteriosclerosis. At times all the symptoms
+seem to be due to the high tension, the relief of which
+causes them to disappear. There are, unfortunately, times
+when high tension is not responsible for the headache and
+insomnia. Under these circumstances such drugs as trional,
+veronal, amylene hydrate, ammonol, etc., may be tried until
+one is found which produces sleep. For the headaches,
+phenacetin, alone or in combination with caffein and bromide
+of sodium, may be tried. Acetanilid, cautiously used,
+is at times of value. There have been cases of arteriosclerosis
+with low blood pressure, accompanied by severe headaches,
+that have been relieved by ergot. Codeine should be
+used with care, and morphine only as a very last resource.</p>
+
+<p>Great care must always be exercised in giving drugs that
+depress the circulation, for it is easily conceivable that more
+harm than good can come from injudicious drugging.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_249" id="Page_249">[249]</a></span></p>
+
+<h2><a name="CHAPTER_XIV" id="CHAPTER_XIV"></a>CHAPTER XIV.</h2>
+
+<h3>ARTERIOSCLEROSIS IN ITS RELATION TO LIFE
+INSURANCE</h3>
+
+
+<p>The value of the early recognition of cases of arteriosclerosis
+and hypertension has been spoken of within, but it
+needs to be further emphasized. There is perhaps no class
+among physicians to whom is afforded a better opportunity
+of seeing early cases than the medical examiners of life
+insurance companies.</p>
+
+<p>The relationship between a patient and the physician
+whom he consults, and the applicant for life insurance and
+the examiner are diametrically opposite. In the former
+the patient desires to conceal nothing and the physician is
+called upon to diagnose and treat disease. In the latter the
+applicant, a presumably healthy person, may have much to
+conceal and the examiner is there to pass upon the state of
+health. The question is this&mdash;"Is the applicant now in
+good health?" It becomes then of vital importance for the
+examiner to be able to detect among other abnormal conditions
+the incipient signs of arteriosclerosis and of hypertension.
+Parenthetically it may be stated that arteriosclerosis
+and hypertension are not one and the same disease as has
+been so frequently insisted upon within; the former may
+occur without the latter but the latter can not from its very
+nature be present for long without arterial thickening supervening.
+It is necessary in discussing the question here
+to group the two conditions together in order to prevent
+needless repetition.</p>
+
+<p>Such a case as the following is common. A successful
+business man of forty-four years was brought to me by an
+agent in 1905 for examination. The man was six feet tall,
+weighed 218 pounds, had a ruddy color and looked to be the<span class="pagenum"><a name="Page_250" id="Page_250">[250]</a></span>
+picture of health. He was not strictly intemperate, he
+never became intoxicated, but every day he drank three or
+four whiskies and often he had a bottle of wine for dinner
+in the evening. When he was examined his pulse was of
+good quality and owing to the fleshiness of the wrist it was
+difficult to say positively whether the radial artery was
+sclerosed or not. In the heart no murmurs were heard, and
+it was difficult to be sure that the left ventricle was enlarged.
+There was, however, a slight but definite accentuation of the
+second sound at the aortic cartilage which might readily
+have been overlooked had the patient not been stripped and
+a careful examination made with the stethoscope. Upon
+taking the blood pressure it was found to be from 170-175
+mm. of Hg. The urine specimen examined at the visit was
+normal, no casts were found. The applicant was seen at
+his home and the blood pressure measured. It was again
+the same. He was seen a third time and practically the
+same systolic blood pressure was found. Under protests
+from all the agency staff the man was declined. Two years
+later he died of apoplexy. The man was angry at being
+refused. Instead of looking the matter squarely in the face
+he thrust aside the idea that there was anything the matter
+with him. He had never had one ill day in his life, his forebears
+had lived to ripe old age, and he was sure that he knew
+more about himself than the examiner.</p>
+
+<p>Had this applicant showed a sense of reasonableness he
+should have been grateful to the doctor for calling his attention
+to a condition which surely would sooner or later prove
+either fatal itself or lead to some fatal lesion. It was
+learned that this man had gone directly to his family physician
+who laughed at such nonsense as had been told the
+(now) patient by the examiner.</p>
+
+<p>Another illustration of a slightly different type of case is
+afforded in the following history.</p>
+
+<p>A man of fifty years of age, five feet ten in height and 164
+lbs. in weight, was brought for examination. In his youth<span class="pagenum"><a name="Page_251" id="Page_251">[251]</a></span>
+there was a history of a mild attack of scarlet fever. He
+was almost a total abstainer, rarely taking liquor in any
+form. Physically he appeared to be an excellent risk.
+However, on examining the heart it was found that there
+was slight hypertrophy with an accentuated second aortic
+sound at the base, and the blood pressure was 180 mm. of
+Hg. Some sclerosis of the radial arteries was found. One
+company had refused him on account of albumin in the
+urine. There was none in the first specimen which was
+passed while in the office. The specific gravity was 1014.
+A morning specimen was obtained and contained a trace of
+albumin. Several specimens were then examined. Some
+contained albumin, some had no albumin content. The man
+was declined; no protests from the agent as albumin had
+been found. There was something tangible in that. Had
+the applicant been refused on account of his high tension,
+sclerosis of the radials, and slightly enlarged heart there
+would undoubtedly have been protests. And yet an applicant
+revealing such a state of the cardiovascular system
+without albumin in the urine should unhesitatingly be declined.
+Attention has been called to hypertension as an
+early, and some think an invariable, sign of chronic nephritis.
+My own experience has confirmed me in the belief
+that in hypertension the kidneys are often the seat of
+chronic interstitial changes. Careful palpation of the radial
+and brachial arteries will in every case reveal more
+or less thickening.</p>
+
+<p>There is yet another group of cases which the examiner
+sees as healthy subjects, namely those cases of sclerosis of
+the peripheral arteries without sclerosis of the aorta and
+without high tension. In such cases the radials, brachials,
+temporals and other superficial arteries are readily palpable,
+sometimes even revealing irregularities along the
+course of a vessel. Such cases are not subjects for insurance.
+The recognition of such a condition is of great importance
+to the one who has it and he should be urged to go to<span class="pagenum"><a name="Page_252" id="Page_252">[252]</a></span>
+his regular physician for thorough examination. Should the
+physician ridicule the idea, as has happened to me more
+than once when I was actively engaged in insurance work,
+the examiner has done his full duty to the company, the
+applicant, and himself.</p>
+
+<p>A life insurance examiner has a difficult position to fill.
+He has four people to satisfy; the applicant, the agent, the
+medical director and himself. The straight and narrow
+path of strict honesty is his only salvation. By being honest
+with himself he necessarily gives a square deal to the
+other three parties.</p>
+
+<p>No applicant who has palpable arteries or hypertension
+can be considered a first class risk. It can not be denied
+that men with arteriosclerosis live to an advanced age and
+may even outlive those who have apparently normal arteries,
+but the average life expectancy at any age for an
+arteriosclerotic is less than that for a normal person. The
+apparently healthy applicant who learns for the first time
+when examined for life insurance that he has the early or
+moderately advanced signs of arterial disease, should thank
+the agent and examiner for showing him the danger signals
+ahead. The sensible man then orders his life so that he
+puts as little strain on his heart, arteries, and kidneys as
+possible and may add many years to his life.</p>
+
+<p>It is on account of this very insidiousness of onset that I
+have elsewhere urged as a prophylactic measure the examination
+every six months of all persons over forty years of
+age. I am more and more convinced that it is of vital importance
+to the health of the public.</p>
+
+<p>As I have remarked, the average man consults his dentist
+at least once a year so that no tooth may be so far diseased
+that it can not be saved. It is purely a means of preserving
+the teeth. Why not do the same with the whole body? Of
+what use is it to save the teeth and lose the body? It seems
+to me that the great army of life insurance examiners are
+in an enviable position in their ability to add years of life<span class="pagenum"><a name="Page_253" id="Page_253">[253]</a></span>
+to many men and women. I doubt whether they realize
+their importance in the campaign for health. I should urge
+life insurance companies not to employ recent graduates
+unless they have had at least a year's hospital experience.
+For the company as well as for the individuals I believe
+that there is a prognostic sense which the examiner should
+have and this can only be acquired by experience.</p>
+
+<p>I believe that arteriosclerosis and hypertension are increasing
+for the reasons which have been given in another
+chapter. There can be no doubt that when these conditions
+are recognized long before symptoms would naturally supervene,
+men and women would not only live longer but
+also die more comfortably and many very likely would be
+carried off by some disease having no relationship whatever
+to arteriosclerosis. Slight enlargement of the heart downward
+and to the left, accentuation of the second aortic
+sound at the base, a full pulse, arteries which are palpably
+thickened, increased blood pressure are signs to which attention
+must be paid.</p>
+
+<p>When the peripheral arteries are palpable they are not
+always sclerosed. The radial artery, the one usually palpated,
+may lie very close to the bone in a thin person. Under
+these conditions the artery can be easily felt. It is
+better then to palpate for the brachial as it lies beneath the
+inner edge of the biceps muscle. Should this artery be felt
+then very probably sclerosis is present. Opinion as to
+whether or not sclerosis is present, when it is slight, may
+differ. It is difficult at times to say definitely. Should
+such be the case the applicant should be most carefully
+questioned as to his family and past history, the heart
+should be carefully outlined by percussion and the blood
+pressure should be taken, both the systolic and diastolic
+pressures. The urine should be examined with particular
+care. I am aware that the average examination for life insurance
+is not made with the care which is bestowed upon a
+patient. Yet I see no reason why the same attention to detail<span class="pagenum"><a name="Page_254" id="Page_254">[254]</a></span>
+should not be given in one as in the other. The examination
+of the great majority of applicants can he made in a
+short time, as there is no question of latent chronic disease.
+When the exception turns up he should be given a searching
+examination and a full report should be sent to the Medical
+Director. Only in this way will it be possible to weed out
+the undesirable risks.</p>
+
+<p>On the surface it does not seem to require any great diagnostic
+acumen to be a life insurance examiner. In the old
+days of many of the companies there were no examiners.
+The applicant was brought before the president or other
+appointed official and he was passed or rejected on his
+general appearance. This has changed, and now the medical
+department with its scores of examiners in the field is
+a well organized department.</p>
+
+<p>It seems to me that the examiner should be an exceedingly
+able diagnostician and prognosticator. There is no telling
+when he may be called upon to pass judgment on a borderline
+case. From personal experience I know how difficult
+it is to make a decision in some cases. These suspicious
+cases after a careful examination had better be passed by
+the examiner and a supplementary report sent to the
+medical director containing unbiased details. But no applicant
+with readily palpable arteries, even though the
+blood pressure be normal, should be considered a first class
+insurance risk.</p>
+
+<p>The question of the value of the diastolic pressure reading
+in examinations for life insurance is not yet settled to
+the satisfaction of all medical directors. Certain medical
+directors with clinical experience behind them, lay great
+stress on the increased diastolic pressure and consider a
+persistent diastolic of 100 mm. really more significant as
+an indication of hypertension than a systolic pressure of
+160 mm. Other directors pay little or no attention to the
+diastolic reading. Should an applicant show a systolic
+above the average normal on several successive readings,<span class="pagenum"><a name="Page_255" id="Page_255">[255]</a></span>
+he is declined. When one takes into consideration the
+psychic effect of knowing that he is being examined for
+high blood pressure, it seems unfair to refuse insurance on
+such grounds as is constantly done.</p>
+
+<p>Up to the present there are no extensive series of life-expectancy
+tables in which hundreds of thousands of cases
+are analyzed from the diastolic pressure values. There are
+many such tables for the systolic pressures alone. In the
+tabulation of such statistics one must not lose sight of the
+important fact that the figures are taken by thousands of
+men of varying capacity and different degrees of intelligence.
+Such studies to be of any real value must be taken
+from records made at the home offices by capable men. We
+shall await these tables with interest. In the meantime we
+must be permitted to have the impression that the diastolic
+pressure has been much neglected. This has no doubt been
+due to the difficulty of measuring it with any degree of accuracy.
+Now with the auscultatory method and the correct
+place to read the diastolic pressure the results of blood
+pressure estimations should begin to have some value for
+statistical data.</p>
+
+<p>Clinically the diastolic is probably more important than
+the systolic. Until proof is brought to the contrary we shall
+believe that in life insurance examinations it has the same
+importance.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_256" id="Page_256">[256]</a></span></p>
+<h2><a name="CHAPTER_XV" id="CHAPTER_XV"></a>CHAPTER XV.</h2>
+
+<h3>PRACTICAL SUGGESTIONS</h3>
+
+
+<p>The time spent in obtaining a careful history of a case
+is time well spent. Often the diagnosis can be made from
+the history alone, the physical examination merely adding
+confirmation to the data already obtained.</p>
+
+<p>The younger the patient who has arteriosclerosis, the
+more probable is it that syphilis is the etiologic factor.
+A denial of infection should have little weight if the history
+of possible exposure is present. Miscarriages in a woman
+should arouse the suspicion of lues in her husband. The
+complement-fixation reaction will often clear up an apparently
+obscure diagnosis.</p>
+
+<p>There are various ways of examining a patient but there
+is only one right way; the examination should be made on
+the bare skin. However skillful one may be in the art of
+physical diagnosis, he can gather few accurate data by examining
+over the clothes even if he use a phonendoscope.</p>
+
+<p>The immoderate eater is laying up for himself a wealth
+of trouble at the time when he can least afford to bear it.
+The ounce of advice in time is worth more to him than the
+pounds of medicine later.</p>
+
+<p>It is a wise maxim never to drive a horse too far. Apply
+that to the human being and the rule holds equally well.</p>
+
+<p>There may be no symptoms in a case of advanced arteriosclerosis.
+Do not on that account neglect to advise a patient
+in whom the disease is accidentally discovered.</p>
+
+<p>Many a man owes a debt of gratitude to the life insurance
+examiner. He rarely feels grateful.</p>
+
+<p>When a competent ophthalmologist refers a case to a general
+practitioner with the statement that he believes from
+the appearance of the fundus of the eye that arteriosclerotic<span class="pagenum"><a name="Page_257" id="Page_257">[257]</a></span>
+changes are present over the body, the case should be most
+carefully examined. The earliest diagnoses are not infrequently
+made by the ophthalmologist.</p>
+
+<p>It is the part of wisdom never to have such a firmly preconceived
+idea of the diagnosis that facts observed are
+perverted in order to fit into the diagnosis. Let the facts
+speak for themselves.</p>
+
+<p>Beware of the snap diagnosis. Even in a case of well-marked
+arteriosclerosis when the diagnosis seems to be
+written in large letters all over the patient, go through the
+routine. Nine times out of ten this may seem needless.
+The tenth time it saves your conscience and reputation.
+Always consider that you are examining a tenth case.</p>
+
+<p>Gradual loss of weight in a person over fifty years old
+should arouse the suspicion of arteriosclerosis.</p>
+
+<p>Do not call the nervous symptoms displayed by a middle-aged
+man or woman neurasthenia until you have ruled out
+all organic causes, particularly arteriosclerosis.</p>
+
+<p>When palpating the radial artery, always use both hands
+according to the method already described. Pay attention
+to the superficial or deep situation of the artery.</p>
+
+<p>The examination of one specimen of urine does not give
+much information, especially if it should be found to contain
+no abnormal elements. Fairly accurate data may be
+gathered from the mixed night and morning urine; most
+accurate data from the twenty-four hour specimen. To be
+of any real value there should be frequent examinations of
+the day's excretion.</p>
+
+<p>In measuring the day's output a good rule is as follows:
+begin to collect urine after the first morning's micturition
+and collect all including the first quantity passed the next
+morning. It is best to examine the centrifugated urine for
+casts even though no albumin be present. It is useless to
+look for casts in an alkaline urine.</p>
+
+<p>Casts are not infrequently found in chemically normal
+urine from a middle-aged patient. Other things being normal,<span class="pagenum"><a name="Page_258" id="Page_258">[258]</a></span>
+the finding has no significance. The kidneys must be
+carefully tested functionally.</p>
+
+<p>Blood pressure readings should always be taken with the
+patient in the same posture at every estimation. At the
+first examination it is advisable to take readings from both
+brachial arteries. Let the patient sit comfortably and relax
+all muscles.</p>
+
+<p>Differentiate as soon as possible between the uncompensated
+heart caused by valvular disease and that caused
+by arteriosclerosis. There is a difference in prognosis.
+Both give the same symptoms, and are treated similarly until
+compensation returns; thereafter the management of the
+two forms is different.</p>
+
+<p>Aortic incompetence that comes on late in life is generally
+the result of curling of the free margins of the valves
+caused by syphilitic arteriosclerosis. Prognosis is grave
+because of the fact that the heart muscle also is the seat of
+degenerative changes and compensatory hypertrophy is established
+with difficulty.</p>
+
+<p>When laying down a regime for a patient, consider his
+disposition, and individualize the treatment. Remember
+that exercise is an essential feature of the hygiene of the
+patient's life but do not forget to be explicit about the
+amount and character of the permissible exercise.</p>
+
+<p>In the prophylaxis of arteriosclerosis, a rational mode of
+living is the all-important factor. As a rule, the less meat
+one eats, the less is the liability of arterial degeneration as
+age advances. The exceptions to this rule are many, and
+probably depend upon the character of the "vital rubber"
+with which the individual begins life.</p>
+
+<p>The diet in well-marked cases of arteriosclerosis should
+be carefully selected with regard to its nutritive and non-irritating
+character. Animal proteins should be sparingly
+used. Milk should have an important place in the dietary.</p>
+
+<p>No drug relieves the pain of uncomplicated aneurysm as
+surely as iodide of potassium.</p>
+
+<p><span class="pagenum"><a name="Page_259" id="Page_259">[259]</a></span>Iodides frequently upset the stomach. Be cautious in the
+use of them. The irritable stomach may turn the scales
+against your patient.</p>
+
+<p>Use cardiac stimulants with care and judgment. If all
+the valuable ammunition is used up at first, the fight will be
+lost.</p>
+
+<p>Use digitalis with especial care. Its chief usefulness is
+in steadying the decompensated heart, improving the conduction
+of impulses, and increasing the tone of the cardiac
+muscle. <i>It should never be given to patients with very slow
+pulses, the subjects of Stokes-Adams syndrome.</i> Digitalis
+has been found to produce partial to complete heart block
+when therapeutically administered.</p>
+
+<p>Remember that in the uncompensated heart morphine not
+only eases the oppressive dyspnea, but also steadies and
+stimulates the heart.</p>
+
+<p>See to it that the patient has a daily movement of the
+bowels. In the early stage try the effect of liquid paraffin
+or of the mineral waters such as Pluto, or Hunyadi Janos,
+or artificial Carlsbad salts (Sprudel salts). These last can
+be made as follows: Sodium chloride, &#8485;I; sodium bicarbonate,
+&#8485;II; sodium sulphate, &#8485;IV. Take two tablespoonsful of
+this in a glass of hot water before breakfast. Should these
+not succeed, assist the action of the drugs by the use of
+enemata. The pill of aloin, strychnine sulphate, and extract
+of cascara, with the addition of a small quantity of hyoscyamus,
+is a mild tonic purgative. In cases of constipation
+with high tension, there is no drug as valuable as calomel or
+one of the other mercurials given occasionally.</p>
+
+<p>Never give Epsom salts unless copious watery stools are
+desired to deplete effusion into the serous cavities or into
+the subcutaneous tissue.</p>
+
+<p>Chronic constipation increases the gravity of the prognosis.</p>
+
+<p>In case of suppression of urine and anasarca, hot air
+packs may be of value. The patient may be wrapped in a<span class="pagenum"><a name="Page_260" id="Page_260">[260]</a></span>
+hot wet sheet and covered with blankets. I do not believe in
+administering pilocarpine to assist the sweating.</p>
+
+<p>Remember to treat the patient and not the disease. The
+careful hygienic and dietetic treatment, combined with the
+least amount of drugging, is the best and most rational
+method of treatment.</p>
+
+<hr style="width: 65%;" />
+<p><span class="pagenum"><a name="Page_261" id="Page_261">[261]</a></span></p>
+<h2>INDEX</h2>
+
+
+
+<div>
+A<br />
+<br />
+Abdominal symptoms, <a href="#Page_201">201</a><br />
+<br />
+Aconite in treatment, <a href="#Page_242">242</a><br />
+<br />
+Acquired arteriosclerosis, <a href="#Page_159">159</a><br />
+<br />
+Adami, effect of syphilis in aorta, <a href="#Page_45">45</a><br />
+<br />
+Adventitia, <a href="#Page_28">28</a><br />
+<br />
+Age in arteriosclerosis, <a href="#Page_161">161</a><br />
+<br />
+Albuminuria, <a href="#Page_221">221</a><br />
+<br />
+Albutt's classification of arteriosclerosis, <a href="#Page_186">186</a><br />
+<br />
+Alcohol, <a href="#Page_166">166</a>, <a href="#Page_228">228</a>, <a href="#Page_235">235</a><br />
+<br />
+Anatomy, <a href="#Page_25">25</a><br />
+<br />
+Angina abdominalis, <a href="#Page_201">201</a>, <a href="#Page_216">216</a><br />
+<span style="margin-left: 1em;">pectoris, <a href="#Page_197">197</a>, <a href="#Page_216">216</a></span><br />
+<span style="margin-left: 2em;">pseudo, <a href="#Page_216">216</a></span><br />
+<br />
+Angiosclerosis, <a href="#Page_26">26</a>, <a href="#Page_64">64</a><br />
+<br />
+Aorta, <a href="#Page_27">27</a><br />
+<span style="margin-left: 1em;">anatomical lesions in, <a href="#Page_33">33</a></span><br />
+<span style="margin-left: 1em;">Aschoff on, <a href="#Page_35">35</a></span><br />
+<span style="margin-left: 1em;">normal, <a href="#Page_41">41</a></span><br />
+<span style="margin-left: 1em;">syphilis in, <a href="#Page_44">44</a></span><br />
+<span style="margin-left: 1em;">thoracic, <a href="#Page_29">29</a></span><br />
+<span style="margin-left: 1em;">thoracic and abdominal, arteriosclerosis of, <a href="#Page_39">39</a></span><br />
+<span style="margin-left: 1em;">velocity of blood in, <a href="#Page_66">66</a></span><br />
+<br />
+Aortic incompetence, <a href="#Page_61">61</a>, <a href="#Page_258">258</a><br />
+<span style="margin-left: 1em;">stenosis, <a href="#Page_60">60</a></span><br />
+<br />
+Aortitis, acute, <a href="#Page_165">165</a><br />
+<br />
+Arcus senilis, <a href="#Page_191">191</a><br />
+<br />
+Arrhythmia, tonal, <a href="#Page_92">92</a>, <a href="#Page_102">102</a><br />
+<br />
+Arterial pressure, <a href="#Page_85">85</a><br />
+<span style="margin-left: 1em;">symptoms, <a href="#Page_189">189</a></span><br />
+<br />
+Arteries, <a href="#Page_29">29</a><br />
+<span style="margin-left: 1em;">examination of, <a href="#Page_172">172</a>, <a href="#Page_177">177</a></span><br />
+<span style="margin-left: 1em;">general structure of, <a href="#Page_27">27</a></span><br />
+<span style="margin-left: 1em;">large, <a href="#Page_30">30</a></span><br />
+<span style="margin-left: 2em;">adventitia of, <a href="#Page_30">30</a></span><br />
+<span style="margin-left: 1em;">palpable, <a href="#Page_189">189</a></span><br />
+<span style="margin-left: 1em;">pulmonary, arteriosclerosis of, <a href="#Page_63">63</a></span><br />
+<br />
+Arteriocapillary fibrosis, <a href="#Page_26">26</a><br />
+<br />
+Arteriosclerotic endocarditis, <a href="#Page_60">60</a>, <a href="#Page_219">219</a><br />
+<br />
+Artery, coronary, cross-section of, <a href="#Page_36">36</a><br />
+<span style="margin-left: 1em;">pulmonary, <a href="#Page_209">209</a></span><br />
+<span style="margin-left: 1em;">radial, <a href="#Page_29">29</a></span><br />
+<br />
+Aschoff on aorta, <a href="#Page_35">35</a><br />
+<br />
+Atheroma, simple, <a href="#Page_32">32</a><br />
+<br />
+Atheromatous abscess, <a href="#Page_38">38</a><br />
+<br />
+Auricular fibrillation, <a href="#Page_133">133</a><br />
+<span style="margin-left: 1em;">flutter, <a href="#Page_131">131</a></span><br />
+<br />
+Auscultation, <a href="#Page_176">176</a><br />
+<br />
+Auscultatory blood pressure phenomenon, <a href="#Page_90">90</a><br />
+<span style="margin-left: 1em;">method of taking blood pressure, <a href="#Page_83">83</a></span><br />
+<span style="margin-left: 1em;">percussion, <a href="#Page_175">175</a></span><br />
+<br />
+<br />
+B<br />
+<br />
+Balneotherapy, <a href="#Page_233">233</a><br />
+<br />
+Basch's blood pressure instrument, <a href="#Page_70">70</a><br />
+<br />
+Blood, circulation of, <a href="#Page_65">65</a><br />
+<span style="margin-left: 1em;">velocity of, <a href="#Page_65">65</a></span><br />
+<span style="margin-left: 2em;">in animals, <a href="#Page_66">66</a></span><br />
+<span style="margin-left: 2em;">in aorta, <a href="#Page_66">66</a></span><br />
+<span style="margin-left: 2em;">in capillaries, <a href="#Page_66">66</a></span><br />
+<span style="margin-left: 1em;">viscosity of, <a href="#Page_68">68</a></span><br />
+<br />
+Blood pressure, <a href="#Page_68">68</a><br />
+<span style="margin-left: 1em;">auscultatory method of taking, <a href="#Page_83">83</a></span><br />
+<span style="margin-left: 1em;">clinical applications of, <a href="#Page_147">147</a></span><br />
+<span style="margin-left: 1em;">diurnal variations of, <a href="#Page_102">102</a></span><br />
+<span style="margin-left: 1em;">drugs influencing, <a href="#Page_120">120</a></span><br />
+<span style="margin-left: 1em;">estimation of, <a href="#Page_179">179</a></span><br />
+<span style="margin-left: 1em;">in cancer, <a href="#Page_118">118</a></span><br />
+<span style="margin-left: 1em;">in collapse, <a href="#Page_118">118</a></span><br />
+<span style="margin-left: 1em;">in exercise, <a href="#Page_105">105</a></span><br />
+<span style="margin-left: 1em;">in head injuries, <a href="#Page_148">148</a></span><br />
+<span style="margin-left: 1em;">in hemorrhages, <a href="#Page_105">105</a>, <a href="#Page_118">118</a>, <a href="#Page_148">148</a></span><br />
+<span style="margin-left: 1em;">in infectious diseases, <a href="#Page_153">153</a></span><br />
+<span style="margin-left: 1em;">in kidney diseases, <a href="#Page_155">155</a></span><br />
+<span style="margin-left: 1em;">in meningitis, <a href="#Page_118">118</a></span><br />
+<span style="margin-left: 1em;">in obstetrics, <a href="#Page_152">152</a></span><br />
+<span style="margin-left: 1em;">in pulmonary tuberculosis, <a href="#Page_119">119</a></span><br />
+<span style="margin-left: 1em;">in shock, <a href="#Page_105">105</a>, <a href="#Page_148">148</a></span><br />
+<span style="margin-left: 1em;">in surgery, <a href="#Page_147">147</a></span><br />
+<span style="margin-left: 1em;">in typhoid fever, <a href="#Page_118">118</a>, <a href="#Page_154">154</a></span><br />
+<span style="margin-left: 1em;">in valvular heart disease, <a href="#Page_155">155</a></span><br />
+<span style="margin-left: 1em;">increase of, <a href="#Page_55">55</a></span><br />
+<span style="margin-left: 1em;">instruments, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Brown's, <a href="#Page_74">74</a></span><br />
+<span style="margin-left: 2em;">Cook's, <a href="#Page_71">71</a></span><br />
+<span style="margin-left: 2em;">Erlanger's, <a href="#Page_72">72</a></span><br />
+<span style="margin-left: 2em;">Faught's, <a href="#Page_75">75</a>, <a href="#Page_80">80</a></span><br />
+<span style="margin-left: 2em;">Hill and Barnard's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Hirschfelder's, <a href="#Page_73">73</a></span><br />
+<span style="margin-left: 2em;">K. Vierordt's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Marcy's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Potain's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Riva Rocci's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">Roger's, <a href="#Page_77">77</a></span><br />
+<span class="pagenum"><a name="Page_262" id="Page_262">[262]</a></span><span style="margin-left: 2em;">Sanborn's, <a href="#Page_80">80</a></span><br />
+<span style="margin-left: 2em;">Stanton's, <a href="#Page_72">72</a></span><br />
+<span style="margin-left: 2em;">technique of, <a href="#Page_80">80</a></span><br />
+<span style="margin-left: 2em;">"Tycos," <a href="#Page_77">77</a></span><br />
+<span style="margin-left: 2em;">v. Basch's, <a href="#Page_70">70</a></span><br />
+<span style="margin-left: 2em;">v. Recklinghausen's, <a href="#Page_76">76</a></span><br />
+<span style="margin-left: 1em;">mechanism of, <a href="#Page_55">55</a></span><br />
+<span style="margin-left: 1em;">normal variations of, <a href="#Page_88">88</a></span><br />
+<span style="margin-left: 1em;">phenomenon, auscultatory, <a href="#Page_90">90</a></span><br />
+<span style="margin-left: 1em;">precautions when estimating, <a href="#Page_181">181</a></span><br />
+<span style="margin-left: 1em;">value of, <a href="#Page_181">181</a></span><br />
+<br />
+Bowman's capsules, sclerosis of, <a href="#Page_62">62</a><br />
+<br />
+Brain, changes in, <a href="#Page_62">62</a><br />
+<br />
+Brown atrophy, <a href="#Page_60">60</a>, <a href="#Page_118">118</a>, <a href="#Page_201">201</a><br />
+<br />
+<br />
+C<br />
+<br />
+Calcification of media, <a href="#Page_43">43</a>, <a href="#Page_59">59</a><br />
+<br />
+Cancer, blood pressure in, <a href="#Page_118">118</a><br />
+<br />
+Capillaries, anatomy of, <a href="#Page_27">27</a>, <a href="#Page_31">31</a><br />
+<br />
+Capillary pulse, <a href="#Page_67">67</a><br />
+<br />
+Cardiac dullness, <a href="#Page_172">172</a><br />
+<span style="margin-left: 1em;">irregularities in arteriosclerosis, <a href="#Page_131">131</a></span><br />
+<span style="margin-left: 1em;">symptoms, <a href="#Page_195">195</a></span><br />
+<br />
+Cerebral symptoms, <a href="#Page_203">203</a><br />
+<br />
+Circulation of blood, <a href="#Page_65">65</a><br />
+<span style="margin-left: 1em;">physiology of, <a href="#Page_65">65</a></span><br />
+<br />
+Cirrhosis of liver, <a href="#Page_64">64</a>, <a href="#Page_216">216</a><br />
+<br />
+Classification of arteriosclerosis, <a href="#Page_32">32</a>, <a href="#Page_37">37</a><br />
+<span style="margin-left: 1em;">Allbutt's, <a href="#Page_186">186</a></span><br />
+<br />
+Collapse, blood pressure in, <a href="#Page_118">118</a><br />
+<br />
+Congenital arteriosclerosis, <a href="#Page_157">157</a><br />
+<br />
+Cook's blood pressure instrument, <a href="#Page_71">71</a><br />
+<br />
+Cor bovinum, <a href="#Page_116">116</a><br />
+<br />
+Coronary artery, cross section of, <a href="#Page_36">36</a><br />
+<br />
+Corpus luteum, <a href="#Page_241">241</a><br />
+<br />
+<br />
+D<br />
+<br />
+Definition of arteriosclerosis, <a href="#Page_26">26</a><br />
+<br />
+Diabetes mellitus, <a href="#Page_216">216</a><br />
+<br />
+Diagnosis, <a href="#Page_210">210</a><br />
+<span style="margin-left: 1em;">differential, <a href="#Page_215">215</a></span><br />
+<span style="margin-left: 1em;">early, <a href="#Page_210">210</a></span><br />
+<span style="margin-left: 1em;">ophthalmic examination in, <a href="#Page_214">214</a></span><br />
+<br />
+Diastolic pressure, <a href="#Page_69">69</a>, <a href="#Page_83">83</a>, <a href="#Page_85">85</a>, <a href="#Page_94">94</a><br />
+<span style="margin-left: 1em;">importance of, <a href="#Page_97">97</a></span><br />
+<br />
+Dicrotic pulse, <a href="#Page_123">123</a><br />
+<br />
+Dietetic treatment, <a href="#Page_235">235</a><br />
+<br />
+Differential diagnosis, <a href="#Page_166">166</a>, <a href="#Page_215">215</a><br />
+<br />
+Diffuse arteriosclerosis, <a href="#Page_32">32</a>, <a href="#Page_37">37</a>, <a href="#Page_38">38</a>, <a href="#Page_57">57</a><br />
+<br />
+Digitalis in treatment, <a href="#Page_246">246</a>, <a href="#Page_259">259</a><br />
+<br />
+Diuretin in treatment, <a href="#Page_246">246</a><br />
+<br />
+Drug intoxications, <a href="#Page_166">166</a><br />
+<br />
+Drugs influencing blood pressure, <a href="#Page_105">105</a>, <a href="#Page_120">120</a><br />
+<br />
+Ductless glands, <a href="#Page_171">171</a><br />
+<br />
+Dullness, cardiac, <a href="#Page_172">172</a><br />
+<br />
+Dyspeptic symptoms, <a href="#Page_184">184</a><br />
+<br />
+Dyspnea, <a href="#Page_184">184</a><br />
+<span style="margin-left: 1em;">treatment of, <a href="#Page_248">248</a></span><br />
+<br />
+<br />
+E<br />
+<br />
+Electrocardiogram, <a href="#Page_126">126</a><br />
+<br />
+Embolism, <a href="#Page_59">59</a><br />
+<br />
+Endarteritis deformans, <a href="#Page_47">47</a><br />
+<span style="margin-left: 1em;">obliterans, <a href="#Page_46">46</a></span><br />
+<br />
+Endocarditis, arteriosclerotic, <a href="#Page_60">60</a>, <a href="#Page_219">219</a><br />
+<br />
+Endothelial lining, <a href="#Page_27">27</a><br />
+<span style="margin-left: 1em;">tubes, <a href="#Page_31">31</a></span><br />
+<br />
+Epistaxis, <a href="#Page_184">184</a>, <a href="#Page_221">221</a><br />
+<br />
+Erlanger's blood pressure instrument, <a href="#Page_72">72</a><br />
+<br />
+Erythromelalgia, <a href="#Page_192">192</a>, <a href="#Page_208">208</a><br />
+<br />
+Estimation of blood pressure, <a href="#Page_179">179</a><br />
+<br />
+Etiology, <a href="#Page_157">157</a><br />
+<br />
+Examination of arteries, <a href="#Page_172">172</a>, <a href="#Page_177">177</a><br />
+<span style="margin-left: 1em;">of heart, <a href="#Page_172">172</a></span><br />
+<span style="margin-left: 1em;">of urine, <a href="#Page_257">257</a></span><br />
+<br />
+Exercise, blood pressure in, <a href="#Page_105">105</a><br />
+<span style="margin-left: 1em;">in prophylaxis, <a href="#Page_225">225</a></span><br />
+<span style="margin-left: 1em;">in treatment, <a href="#Page_230">230</a></span><br />
+<br />
+Experimental arteriosclerosis, <a href="#Page_50">50</a><br />
+<br />
+Extrasystole, <a href="#Page_138">138</a><br />
+<br />
+<br />
+F<br />
+<br />
+Faught's blood pressure instrument, <a href="#Page_75">75</a>, <a href="#Page_80">80</a><br />
+<br />
+Fibrillation, auricular, <a href="#Page_133">133</a><br />
+<span style="margin-left: 1em;">ventricular, <a href="#Page_138">138</a></span><br />
+<br />
+Fibrolysin in treatment, <a href="#Page_243">243</a><br />
+<br />
+Fingernail palpation, <a href="#Page_178">178</a><br />
+<br />
+Finger tip palpation, <a href="#Page_179">179</a><br />
+<br />
+Flutter, auricular, <a href="#Page_131">131</a><br />
+<br />
+Food poisons in arteriosclerosis, <a href="#Page_163">163</a><br />
+<br />
+<br />
+G<br />
+<br />
+Gibson's law, <a href="#Page_154">154</a><br />
+<br />
+<br />
+H<br />
+<br />
+"H" wave, <a href="#Page_126">126</a><br />
+<br />
+Habits, personal, <a href="#Page_234">234</a><br />
+<br />
+Head injuries, blood pressure in, <a href="#Page_148">148</a><br />
+<br />
+Headache, <a href="#Page_184">184</a><br />
+<span style="margin-left: 1em;">treatment of, <a href="#Page_248">248</a></span><br />
+<br />
+Heart block, <a href="#Page_140">140</a><br />
+<span style="margin-left: 1em;">boundaries, <a href="#Page_172">172</a></span><br />
+<span style="margin-left: 1em;">examination of, <a href="#Page_172">172</a></span><br />
+<span style="margin-left: 1em;">hypertrophy of, <a href="#Page_60">60</a></span><br />
+<span style="margin-left: 1em;">physical examination of, <a href="#Page_172">172</a></span><br />
+<span style="margin-left: 1em;">stimulants, <a href="#Page_243">243</a>, <a href="#Page_246">246</a>, <a href="#Page_259">259</a></span><br />
+<span style="margin-left: 1em;">symptoms, <a href="#Page_188">188</a></span><br />
+<span class="pagenum"><a name="Page_263" id="Page_263">[263]</a></span><br />
+Hemorrhages, blood pressure in, <a href="#Page_118">118</a><br />
+<br />
+Henle, membrane of, <a href="#Page_29">29</a><br />
+<br />
+Hill and Barnard's blood pressure instrument, <a href="#Page_70">70</a><br />
+<br />
+Hirschfelder's blood pressure instrument, <a href="#Page_73">73</a><br />
+<br />
+His, bundle of, <a href="#Page_141">141</a>, <a href="#Page_197">197</a><br />
+<br />
+Hygienic treatment, <a href="#Page_230">230</a><br />
+<br />
+Hyperpietic arteriosclerosis, <a href="#Page_186">186</a><br />
+<br />
+Hypertension, <a href="#Page_60">60</a>, <a href="#Page_106">106</a>, <a href="#Page_169">169</a>, <a href="#Page_185">185</a>, <a href="#Page_249">249</a><br />
+<span style="margin-left: 1em;">cause of arteriosclerosis, <a href="#Page_159">159</a></span><br />
+<span style="margin-left: 1em;">classification of cases, <a href="#Page_112">112</a></span><br />
+<br />
+Hypertrophy of left ventricle, <a href="#Page_58">58</a><br />
+<br />
+Hypotension, <a href="#Page_117">117</a><br />
+<br />
+<br />
+I<br />
+<br />
+Incompetence, aortic, <a href="#Page_61">61</a>, <a href="#Page_258">258</a><br />
+<br />
+Indicanuria, <a href="#Page_167">167</a><br />
+<br />
+Infants, arteriosclerosis in, <a href="#Page_158">158</a><br />
+<br />
+Infectious diseases in arteriosclerosis, <a href="#Page_163">163</a><br />
+<span style="margin-left: 1em;">blood pressure in, <a href="#Page_153">153</a></span><br />
+<br />
+Insomnia, treatment of, <a href="#Page_248">248</a><br />
+<br />
+Intermittent claudication, <a href="#Page_192">192</a>, <a href="#Page_208">208</a><br />
+<span style="margin-left: 1em;">treatment of, <a href="#Page_247">247</a></span><br />
+<br />
+Intoxications, chronic drug, <a href="#Page_166">166</a><br />
+<br />
+Intracranial tension, <a href="#Page_105">105</a><br />
+<br />
+Involutionary arteriosclerosis, <a href="#Page_187">187</a><br />
+<br />
+Iodides in treatment, <a href="#Page_238">238</a>, <a href="#Page_247">247</a>, <a href="#Page_259">259</a><br />
+<br />
+<br />
+K<br />
+<br />
+Kidney diseases, blood pressure in, <a href="#Page_155">155</a><br />
+<br />
+Kidneys, sclerosis of, <a href="#Page_61">61</a>, <a href="#Page_170">170</a><br />
+<br />
+<br />
+L<br />
+<br />
+Life insurance, relation to, <a href="#Page_249">249</a><br />
+<br />
+Light percussion, <a href="#Page_174">174</a><br />
+<span style="margin-left: 1em;">touch palpation, <a href="#Page_175">175</a></span><br />
+<br />
+Liver, cirrhosis, <a href="#Page_64">64</a>, <a href="#Page_216">216</a><br />
+<br />
+Local symptoms, <a href="#Page_207">207</a><br />
+<br />
+<br />
+M<br />
+<br />
+Marey's blood pressure instrument, <a href="#Page_70">70</a><br />
+<br />
+Maximum pressure, <a href="#Page_85">85</a>, <a href="#Page_94">94</a><br />
+<br />
+Mean pressure, <a href="#Page_85">85</a><br />
+<br />
+Media, calcification of, <a href="#Page_43">43</a>, <a href="#Page_59">59</a><br />
+<br />
+Medicinal treatment, <a href="#Page_238">238</a><br />
+<br />
+Meningitis, blood pressure in, <a href="#Page_118">118</a><br />
+<br />
+Mental strain, <a href="#Page_168">168</a><br />
+<br />
+Mesaortitis, <a href="#Page_45">45</a>, <a href="#Page_47">47</a>, <a href="#Page_49">49</a>, <a href="#Page_165">165</a><br />
+<br />
+Mesentery, cross-section of small artery in, <a href="#Page_56">56</a><br />
+<br />
+Milk diet, <a href="#Page_237">237</a><br />
+<br />
+Minimum pressure, <a href="#Page_86">86</a>, <a href="#Page_94">94</a><br />
+<br />
+Moenckeberg type of arteriosclerosis, <a href="#Page_43">43</a><br />
+<br />
+Morphine in treatment, <a href="#Page_243">243</a><br />
+<br />
+Mosenthal test meal, <a href="#Page_221">221</a><br />
+<br />
+Muscular overwork, <a href="#Page_169">169</a><br />
+<br />
+<br />
+N<br />
+<br />
+Nervous symptoms, <a href="#Page_191">191</a><br />
+<br />
+Nitrites in treatment, <a href="#Page_240">240</a><br />
+<br />
+Nitroglycerin in treatment, <a href="#Page_241">241</a><br />
+<br />
+Nodular arteriosclerosis, <a href="#Page_32">32</a>, <a href="#Page_37">37</a><br />
+<br />
+Normal blood pressure variation, <a href="#Page_88">88</a><br />
+<br />
+<br />
+O<br />
+<br />
+Obstetrics, blood pressure in, <a href="#Page_152">152</a><br />
+<br />
+Occupation in arteriosclerosis, <a href="#Page_162">162</a><br />
+<br />
+Ocular symptoms, <a href="#Page_190">190</a><br />
+<br />
+Ophthalmic examination, importance in early diagnosis, <a href="#Page_214">214</a>, <a href="#Page_256">256</a><br />
+<br />
+Orthodiagraph, <a href="#Page_173">173</a><br />
+<br />
+Overeating, <a href="#Page_167">167</a>, <a href="#Page_212">212</a>, <a href="#Page_225">225</a>, <a href="#Page_235">235</a><br />
+<br />
+Overwork, muscular, <a href="#Page_169">169</a><br />
+<br />
+<br />
+P<br />
+<br />
+"P" wave, <a href="#Page_129">129</a><br />
+<br />
+"P-R" interval, <a href="#Page_130">130</a><br />
+<br />
+Palpable arteries, <a href="#Page_189">189</a><br />
+<br />
+Palpation, <a href="#Page_174">174</a>, <a href="#Page_180">180</a><br />
+<span style="margin-left: 1em;">fingernail, <a href="#Page_178">178</a></span><br />
+<span style="margin-left: 1em;">finger tip, <a href="#Page_179">179</a></span><br />
+<span style="margin-left: 1em;">light touch, <a href="#Page_175">175</a></span><br />
+<br />
+Pathology, <a href="#Page_32">32</a><br />
+<br />
+Percussion, <a href="#Page_174">174</a><br />
+<span style="margin-left: 1em;">auscultatory, <a href="#Page_175">175</a></span><br />
+<span style="margin-left: 1em;">light, <a href="#Page_174">174</a></span><br />
+<br />
+Peripheral symptoms, <a href="#Page_207">207</a><br />
+<br />
+Personal habits, <a href="#Page_234">234</a><br />
+<br />
+Phlebosclerosis, <a href="#Page_64">64</a><br />
+<br />
+Phthalein test, <a href="#Page_221">221</a><br />
+<br />
+Physical signs, <a href="#Page_183">183</a><br />
+<br />
+Physiology of the circulation, <a href="#Page_65">65</a><br />
+<br />
+Potain's blood pressure instrument, <a href="#Page_70">70</a><br />
+<br />
+Practical suggestions, <a href="#Page_256">256</a><br />
+<br />
+Pressure, arterial, <a href="#Page_85">85</a><br />
+<span style="margin-left: 1em;">ausculatory method of determining, <a href="#Page_83">83</a></span><br />
+<span style="margin-left: 1em;">diastolic, <a href="#Page_83">83</a>, <a href="#Page_94">94</a></span><br />
+<span style="margin-left: 1em;">estimation of, <a href="#Page_179">179</a></span><br />
+<span style="margin-left: 1em;">in surgery, <a href="#Page_147">147</a></span><br />
+<span style="margin-left: 1em;">maximum, <a href="#Page_85">85</a>, <a href="#Page_94">94</a></span><br />
+<span style="margin-left: 1em;">normal variations, <a href="#Page_88">88</a></span><br />
+<span style="margin-left: 1em;">pulse, <a href="#Page_83">83</a>, <a href="#Page_85">85</a>, <a href="#Page_87">87</a>, <a href="#Page_100">100</a></span><br />
+<span style="margin-left: 1em;">systolic, <a href="#Page_82">82</a>, <a href="#Page_85">85</a></span><br />
+<span style="margin-left: 1em;">technique, <a href="#Page_80">80</a></span><br />
+<span style="margin-left: 1em;">venous, <a href="#Page_120">120</a></span><br />
+<span class="pagenum"><a name="Page_264" id="Page_264">[264]</a></span><br />
+Prognosis, <a href="#Page_218">218</a><br />
+<br />
+Prophylaxis, <a href="#Page_224">224</a><br />
+<span style="margin-left: 1em;">exercise in, <a href="#Page_225">225</a></span><br />
+<br />
+Pseudo angina pectoris, <a href="#Page_216">216</a><br />
+<br />
+Pulmonary artery, <a href="#Page_209">209</a><br />
+<span style="margin-left: 1em;">arteriosclerosis of, <a href="#Page_63">63</a></span><br />
+<span style="margin-left: 1em;">tuberculosis, blood pressure in, <a href="#Page_119">119</a></span><br />
+<br />
+Pulse, <a href="#Page_123">123</a><br />
+<span style="margin-left: 1em;">capillary, <a href="#Page_67">67</a></span><br />
+<span style="margin-left: 1em;">deficit, <a href="#Page_135">135</a></span><br />
+<span style="margin-left: 1em;">dicrotic, <a href="#Page_123">123</a></span><br />
+<span style="margin-left: 1em;">in arteriosclerosis, <a href="#Page_123">123</a></span><br />
+<span style="margin-left: 1em;">pressure, <a href="#Page_69">69</a>, <a href="#Page_83">83</a>, <a href="#Page_85">85</a>, <a href="#Page_87">87</a>, <a href="#Page_100">100</a></span><br />
+<span style="margin-left: 1em;">rate, <a href="#Page_69">69</a></span><br />
+<span style="margin-left: 1em;">venous, <a href="#Page_123">123</a></span><br />
+<br />
+Purgatives in treatment, <a href="#Page_244">244</a>, <a href="#Page_259">259</a><br />
+<br />
+Pyrosis, <a href="#Page_184">184</a><br />
+<br />
+<br />
+Q<br />
+<br />
+"Q R S" complex, <a href="#Page_129">129</a><br />
+<br />
+<br />
+R<br />
+<br />
+Rabbits, lesions produced experimentally in, <a href="#Page_50">50</a><br />
+<br />
+Race in arteriosclerosis, <a href="#Page_161">161</a><br />
+<br />
+Radial artery, <a href="#Page_29">29</a><br />
+<br />
+Radials, sclerosis of, <a href="#Page_43">43</a><br />
+<br />
+Raynaud's disease, <a href="#Page_192">192</a>, <a href="#Page_207">207</a><br />
+<br />
+Recklinghausen's blood pressure instrument, <a href="#Page_76">76</a><br />
+<br />
+Renal disease, <a href="#Page_169">169</a><br />
+<span style="margin-left: 1em;">symptoms, <a href="#Page_199">199</a></span><br />
+<br />
+Rest in treatment, <a href="#Page_242">242</a><br />
+<br />
+Riva-Rocci's blood pressure instrument, <a href="#Page_70">70</a><br />
+<br />
+Rogers' blood pressure instrument, <a href="#Page_77">77</a><br />
+<br />
+<br />
+S<br />
+<br />
+Sanborn's blood pressure instrument, <a href="#Page_80">80</a><br />
+<br />
+Scaphoid scapula, <a href="#Page_158">158</a><br />
+<br />
+Schwellungsperkussion, <a href="#Page_174">174</a><br />
+<br />
+Sclerosis of veins, <a href="#Page_64">64</a><br />
+<br />
+Senile arteriosclerosis, <a href="#Page_32">32</a>, <a href="#Page_37">37</a>, <a href="#Page_43">43</a>, <a href="#Page_59">59</a><br />
+<br />
+Sex in arteriosclerosis, <a href="#Page_161">161</a><br />
+<br />
+Shock, blood pressure in, <a href="#Page_105">105</a>, <a href="#Page_148">148</a><br />
+<br />
+Spinal symptoms, <a href="#Page_205">205</a><br />
+<br />
+Spirochaeta pallida, <a href="#Page_45">45</a><br />
+<br />
+Stanton's blood pressure instrument, <a href="#Page_72">72</a><br />
+<br />
+Stenosis, aortic, <a href="#Page_60">60</a><br />
+<br />
+Stokes-Adams syndrome, <a href="#Page_197">197</a><br />
+<br />
+Stomach, ulcer of, <a href="#Page_216">216</a><br />
+<br />
+Strain hypertrophy, <a href="#Page_47">47</a>, <a href="#Page_54">54</a>, <a href="#Page_55">55</a><br />
+<br />
+Surgery, blood pressure in, <a href="#Page_147">147</a><br />
+<br />
+Symptomatic treatment, <a href="#Page_245">245</a><br />
+<br />
+Symptoms, <a href="#Page_183">183</a><br />
+<span style="margin-left: 1em;">abdominal, <a href="#Page_201">201</a></span><br />
+<span style="margin-left: 1em;">arterial, <a href="#Page_189">189</a></span><br />
+<span style="margin-left: 1em;">cardiac, <a href="#Page_195">195</a></span><br />
+<span style="margin-left: 1em;">cerebral, <a href="#Page_203">203</a></span><br />
+<span style="margin-left: 1em;">dyspeptic, <a href="#Page_184">184</a></span><br />
+<span style="margin-left: 1em;">dyspnea, <a href="#Page_184">184</a></span><br />
+<span style="margin-left: 1em;">general, <a href="#Page_183">183</a></span><br />
+<span style="margin-left: 1em;">headache, <a href="#Page_184">184</a></span><br />
+<span style="margin-left: 1em;">heart, <a href="#Page_188">188</a></span><br />
+<span style="margin-left: 1em;">local, <a href="#Page_207">207</a></span><br />
+<span style="margin-left: 1em;">nervous, <a href="#Page_191">191</a></span><br />
+<span style="margin-left: 1em;">ocular, <a href="#Page_190">190</a></span><br />
+<span style="margin-left: 1em;">peripheral, <a href="#Page_207">207</a></span><br />
+<span style="margin-left: 1em;">pyrosis, <a href="#Page_184">184</a></span><br />
+<span style="margin-left: 1em;">renal, <a href="#Page_199">199</a></span><br />
+<span style="margin-left: 1em;">special, <a href="#Page_194">194</a></span><br />
+<span style="margin-left: 1em;">spinal, <a href="#Page_205">205</a></span><br />
+<span style="margin-left: 1em;">vertigo, <a href="#Page_184">184</a></span><br />
+<span style="margin-left: 1em;">visceral, <a href="#Page_201">201</a></span><br />
+<br />
+Syphilis, <a href="#Page_165">165</a><br />
+<span style="margin-left: 1em;">in aorta, <a href="#Page_44">44</a></span><br />
+<br />
+Syphilitic arteriosclerosis, <a href="#Page_37">37</a><br />
+<br />
+Systolic pressure, <a href="#Page_69">69</a>, <a href="#Page_82">82</a>, <a href="#Page_85">85</a>, <a href="#Page_94">94</a><br />
+<span style="margin-left: 1em;">importance of, <a href="#Page_97">97</a></span><br />
+<br />
+<br />
+T<br />
+<br />
+"T" wave, <a href="#Page_130">130</a><br />
+<br />
+Technique of blood pressure instruments, <a href="#Page_80">80</a><br />
+<br />
+Thayer and Fabyan, <a href="#Page_34">34</a><br />
+<br />
+Theocin, <a href="#Page_247">247</a><br />
+<br />
+Thoma on arteriosclerosis, <a href="#Page_33">33</a><br />
+<br />
+Thoracic aorta, <a href="#Page_29">29</a><br />
+<br />
+Thyroid extract in treatment, <a href="#Page_239">239</a><br />
+<br />
+Tobacco, <a href="#Page_167">167</a>, <a href="#Page_212">212</a>, <a href="#Page_234">234</a><br />
+<br />
+Tonal arrhythmia, <a href="#Page_92">92</a>, <a href="#Page_102">102</a><br />
+<br />
+Toxic arteriosclerosis, <a href="#Page_186">186</a><br />
+<br />
+Treatment, <a href="#Page_229">229</a><br />
+<span style="margin-left: 1em;">aconite in, <a href="#Page_242">242</a></span><br />
+<span style="margin-left: 1em;">balneotherapy in, <a href="#Page_233">233</a></span><br />
+<span style="margin-left: 1em;">corpus luteum, <a href="#Page_241">241</a></span><br />
+<span style="margin-left: 1em;">dietetic, <a href="#Page_235">235</a></span><br />
+<span style="margin-left: 1em;">digitalis in, <a href="#Page_246">246</a>, <a href="#Page_259">259</a></span><br />
+<span style="margin-left: 1em;">diuretin in, <a href="#Page_246">246</a></span><br />
+<span style="margin-left: 1em;">exercise in, <a href="#Page_230">230</a></span><br />
+<span style="margin-left: 1em;">fibrolysin in, <a href="#Page_243">243</a></span><br />
+<span style="margin-left: 1em;">heart stimulants in, <a href="#Page_243">243</a></span><br />
+<span style="margin-left: 1em;">hygienic, <a href="#Page_230">230</a></span><br />
+<span style="margin-left: 1em;">iodides in, <a href="#Page_238">238</a>, <a href="#Page_247">247</a>, <a href="#Page_259">259</a></span><br />
+<span style="margin-left: 1em;">medicinal, <a href="#Page_238">238</a></span><br />
+<span style="margin-left: 1em;">morphine in, <a href="#Page_243">243</a></span><br />
+<span style="margin-left: 1em;">nitrites in, <a href="#Page_240">240</a></span><br />
+<span style="margin-left: 1em;">nitroglycerin in, <a href="#Page_241">241</a></span><br />
+<span style="margin-left: 1em;">of dyspnea, <a href="#Page_248">248</a></span><br />
+<span class="pagenum"><a name="Page_265" id="Page_265">[265]</a></span><span style="margin-left: 1em;">of headache, <a href="#Page_248">248</a></span><br />
+<span style="margin-left: 1em;">of insomnia, <a href="#Page_248">248</a></span><br />
+<span style="margin-left: 1em;">of intermittent claudication, <a href="#Page_247">247</a></span><br />
+<span style="margin-left: 1em;">personal habits in, <a href="#Page_234">234</a></span><br />
+<span style="margin-left: 1em;">purgatives in, <a href="#Page_244">244</a>, <a href="#Page_259">259</a></span><br />
+<span style="margin-left: 1em;">rest in, <a href="#Page_242">242</a></span><br />
+<span style="margin-left: 1em;">symptomatic, <a href="#Page_245">245</a></span><br />
+<span style="margin-left: 1em;">theocin in, <a href="#Page_247">247</a></span><br />
+<span style="margin-left: 1em;">thyroid extract in, <a href="#Page_239">239</a></span><br />
+<span style="margin-left: 1em;">Trunecek's serum in, <a href="#Page_243">243</a></span><br />
+<span style="margin-left: 1em;">venesection in, <a href="#Page_242">242</a></span><br />
+<span style="margin-left: 1em;">veratrum viride in, <a href="#Page_242">242</a></span><br />
+<br />
+Trunecek's serum in treatment, <a href="#Page_243">243</a><br />
+<br />
+Tuberculosis, blood pressure in, <a href="#Page_119">119</a><br />
+<br />
+Tunica intima, <a href="#Page_28">28</a><br />
+<span style="margin-left: 1em;">media, <a href="#Page_28">28</a></span><br />
+<br />
+"Tycos" blood pressure instrument, <a href="#Page_77">77</a><br />
+<br />
+Typhoid fever as cause of arteriosclerosis, <a href="#Page_164">164</a><br />
+<span style="margin-left: 1em;">blood pressure in, <a href="#Page_118">118</a></span><br />
+<br />
+<br />
+U<br />
+<br />
+Ulcer of stomach, <a href="#Page_216">216</a><br />
+<br />
+Urine, examination of, <a href="#Page_257">257</a><br />
+<span style="margin-left: 1em;">suppression of, <a href="#Page_259">259</a></span><br />
+<br />
+<br />
+V<br />
+<br />
+Valvular heart disease, blood pressure in, <a href="#Page_155">155</a><br />
+<br />
+Vasa vasorum, <a href="#Page_29">29</a><br />
+<br />
+Veins, anatomy of, <a href="#Page_30">30</a><br />
+<span style="margin-left: 1em;">sclerosis of, <a href="#Page_64">64</a></span><br />
+<br />
+Velocity of blood in animals, <a href="#Page_66">66</a><br />
+<span style="margin-left: 1em;">of blood in aorta, <a href="#Page_66">66</a></span><br />
+<br />
+Venesection in treatment, <a href="#Page_242">242</a><br />
+<br />
+Venous pressure, <a href="#Page_120">120</a><br />
+<span style="margin-left: 1em;">pulse, <a href="#Page_123">123</a></span><br />
+<br />
+Ventricle, left, hypertrophy of, <a href="#Page_58">58</a><br />
+<br />
+Ventricular fibrillation, <a href="#Page_138">138</a><br />
+<br />
+Veratrum viride in treatment, <a href="#Page_242">242</a><br />
+<br />
+Vertigo, <a href="#Page_184">184</a><br />
+</div>
+
+
+
+
+
+<h3>FOOTNOTES:</h3>
+
+<div class="footnote"><p><a name="Footnote_1_1" id="Footnote_1_1"></a><a href="#FNanchor_1_1"><span class="label">[1]</span></a> Longcope and McClintock, however, conclude that permanent constriction of the
+superior mesenteric artery and celiac axis, as well as gradual occlusion of one or both
+of these vessels, may be present in dogs for at least five months without giving rise to
+definite and constant elevation of blood pressure or to hypertrophy of the heart. Further,
+they have been unable to find at autopsy on man a definite association between sclerosis
+of the abdominal aorta and great splanchnic vessels and cardiac hypertrophy.</p></div>
+
+<div class="footnote"><p><a name="Footnote_2_2" id="Footnote_2_2"></a><a href="#FNanchor_2_2"><span class="label">[2]</span></a> Warthin, A. S.: Am. Jour. Syph., 1918, i, 693.</p></div>
+
+<div class="footnote"><p><a name="Footnote_3_3" id="Footnote_3_3"></a><a href="#FNanchor_3_3"><span class="label">[3]</span></a> A firm makes a stethoscope so that the bell is clamped on the arm leaving both the
+operator's hands free.</p></div>
+
+<div class="footnote"><p><a name="Footnote_4_4" id="Footnote_4_4"></a><a href="#FNanchor_4_4"><span class="label">[4]</span></a> Weyse, A. W., and Lutz, B. R.: Diurnal Variations in Arterial Blood Pressure,
+Am. Jour. Physiol., 1915, xxxvii, 330.</p></div>
+
+<div class="footnote"><p><a name="Footnote_5_5" id="Footnote_5_5"></a><a href="#FNanchor_5_5"><span class="label">[5]</span></a> Erlanger and Hooker: An Experimental Study of Blood Pressure and of Pulse
+Pressure in Man, Johns Hopkins Hosp. Rep., 1904, xii, 145.</p></div>
+
+<div class="footnote"><p><a name="Footnote_6_6" id="Footnote_6_6"></a><a href="#FNanchor_6_6"><span class="label">[6]</span></a> Dawson and Gorham: The Pulse Pressure as an Index of Systolic Output, Jour.
+Exper. Med., 1908, x, 484.</p></div>
+
+<div class="footnote"><p><a name="Footnote_7_7" id="Footnote_7_7"></a><a href="#FNanchor_7_7"><span class="label">[7]</span></a> Isolation of a New Vasoconstrictor Substance from the Blood and the Adrenal Cortex,
+Jour. Am. Med. Assn., 1913, lxi, 2136.</p></div>
+
+<div class="footnote"><p><a name="Footnote_8_8" id="Footnote_8_8"></a><a href="#FNanchor_8_8"><span class="label">[8]</span></a> Stone, W. J.: The Differentiation of Cerebral and Cardiac Types of Hyperarterial
+Tension in Vascular Diseases, Arch. Int. Med., November, 1915, p. 775.</p></div>
+
+<div class="footnote"><p><a name="Footnote_9_9" id="Footnote_9_9"></a><a href="#FNanchor_9_9"><span class="label">[9]</span></a> Smith, W. H., and Kilgore, A. R.: Dilatation of the Arch of the Aorta in Chronic
+Nephritis with Hypertension, Am. Jour. Med. Sc., 1915, cxlix, 503.</p></div>
+
+<div class="footnote"><p><a name="Footnote_10_10" id="Footnote_10_10"></a><a href="#FNanchor_10_10"><span class="label">[10]</span></a> McCrae, Thomas: Dilatation of the Arch of the Aorta, Am. Jour. Med. Sc., 1910,
+cxl, 469.</p></div>
+
+<div class="footnote"><p><a name="Footnote_11_11" id="Footnote_11_11"></a><a href="#FNanchor_11_11"><span class="label">[11]</span></a> Stone, W. J.: Arch. Int. Med., 1915, xvl, 775.</p></div>
+
+<div class="footnote"><p><a name="Footnote_12_12" id="Footnote_12_12"></a><a href="#FNanchor_12_12"><span class="label">[12]</span></a> Robinson, G. C., and Bredeck, J. F.: Arch. Int. Med., 1917, xx, 725.</p></div>
+
+<div class="footnote"><p><a name="Footnote_13_13" id="Footnote_13_13"></a><a href="#FNanchor_13_13"><span class="label">[13]</span></a> Jour. Exper. Med., 1911, xiv, 217.</p></div>
+
+<div class="footnote"><p><a name="Footnote_14_14" id="Footnote_14_14"></a><a href="#FNanchor_14_14"><span class="label">[14]</span></a> Warfield, L. M.: Jour. Lab. and Clin. Med., November, 1917.</p></div>
+
+<div class="footnote"><p><a name="Footnote_15_15" id="Footnote_15_15"></a><a href="#FNanchor_15_15"><span class="label">[15]</span></a> From &#960;&#953;&#949;&#963;&#969; to squeeze, oppress or distress. Hyperpiesis, therefore, signifies excessive
+pressure.</p></div>
+
+<div class="footnote"><p><a name="Footnote_16_16" id="Footnote_16_16"></a><a href="#FNanchor_16_16"><span class="label">[16]</span></a> I have found the small colorimeter made by Hynson, Westcott and Dunning,
+Baltimore, Mo., costing $5.00, a very practical instrument.</p></div>
+
+<div class="footnote"><p><a name="Footnote_17_17" id="Footnote_17_17"></a><a href="#FNanchor_17_17"><span class="label">[17]</span></a> Mosenthal, H. O.: Arch. Int. Med., 1915, xvi, 733.</p></div>
+
+<div class="footnote"><p><a name="Footnote_18_18" id="Footnote_18_18"></a><a href="#FNanchor_18_18"><span class="label">[18]</span></a> Myers and Lough: Arch. Int. Med., 1915, xvi, 536.</p></div>
+
+<div class="footnote"><p><a name="Footnote_19_19" id="Footnote_19_19"></a><a href="#FNanchor_19_19"><span class="label">[19]</span></a> Discussion of alcohol at present has value only as it relates to the past. The present
+is dry. The future is in the lap of the gods.</p></div>
+
+<div class="footnote"><p><a name="Footnote_20_20" id="Footnote_20_20"></a><a href="#FNanchor_20_20"><span class="label">[20]</span></a> Miller, Jos. L.: Hypertension and the Value of the Various Methods for Its Reduction.
+Jour. Am. Med. Assn., 1910, liv, p. 1666.</p></div>
+
+<div class="footnote"><p><a name="Footnote_21_21" id="Footnote_21_21"></a><a href="#FNanchor_21_21"><span class="label">[21]</span></a> I have taken as much as 1700 c.c. from a large man. He recovered and went back
+to work.</p></div>
+<hr style="width: 65%;" />
+<div class='tn'><h3>Transcriber's Notes:</h3>
+<p>Irregular hyphenation has been preserved, as in
+blood pressure and blood-pressure. Both "Hg" and "Hg." appear.</p>
+
+<p>Minor typographical errors and inconsistencies have been silently
+normalized.</p>
+<p>The original printed list of illustrations shows the original locations; they have been moved
+closer to their discussion area in the text to not interrupt the flow of reading.
+</p>
+
+</div>
+
+
+
+
+
+
+
+<pre>
+
+
+
+
+
+End of the Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
+*** END OF THIS PROJECT GUTENBERG EBOOK ARTERIOSCLEROSIS AND HYPERTENSION: ***
+
+***** This file should be named 37675-h.htm or 37675-h.zip *****
+This and all associated files of various formats will be found in:
+ http://www.gutenberg.org/3/7/6/7/37675/
+
+Produced by Bryan Ness, Julia Neufeld and the Online
+Distributed Proofreading Team at http://www.pgdp.net (This
+file was produced from images generously made available
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+The Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever. You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+Title: Arteriosclerosis and Hypertension:
+ with Chapters on Blood Pressure, 3rd Edition.
+
+Author: Louis Marshall Warfield
+
+Release Date: October 12, 2011 [EBook #37675]
+
+Language: English
+
+Character set encoding: ASCII
+
+*** START OF THIS PROJECT GUTENBERG EBOOK ARTERIOSCLEROSIS AND HYPERTENSION: ***
+
+
+
+
+Produced by Bryan Ness, Julia Neufeld and the Online
+Distributed Proofreading Team at http://www.pgdp.net (This
+file was produced from images generously made available
+by The Internet Archive/American Libraries.)
+
+
+
+
+
+
+
+Transcriber's Notes: Passages in italics are indicated by _underscores_.
+
+Passages in bold are surrounded by =.
+
+Small caps have been replaced by ALL CAPS.
+
+
+
+
+ERRATUM
+
+
+Page 75, Figure shown is not the Brown sphygmomanometer described in the
+text, but the Baumanometer manufactured by W. A. Baum Co., Inc., New
+York. It is claimed that the Baumanometer is made with particular care
+and hence the readings are said to be more accurate than other mercury
+instruments. It is apparently a good instrument. The author has had no
+personal experience with it.
+
+
+
+
+ ARTERIOSCLEROSIS
+
+ AND
+
+ HYPERTENSION
+
+ With Chapters on Blood Pressure
+
+ BY
+
+ LOUIS M. WARFIELD, A.B., M.D., (Johns Hopkins),
+ F.A.C.P.
+
+ FORMERLY PROFESSOR OF CLINICAL MEDICINE, MARQUETTE UNIVERSITY MEDICAL
+ SCHOOL; CHIEF PHYSICIAN TO MILWAUKEE COUNTY HOSPITAL; ASSOCIATE
+ MEMBER ASSOCIATION AMERICAN PHYSICIANS; MEMBER AMERICAN
+ ASSOCIATION PATHOLOGISTS AND BACTERIOLOGISTS;
+ AMERICAN MEDICAL ASSOCIATION, ETC., FELLOW
+ AMERICAN COLLEGE OF PHYSICIANS
+
+ _THIRD EDITION_
+
+ ST. LOUIS
+
+ C. V. MOSBY COMPANY
+
+ 1920
+
+ COPYRIGHT, 1912, 1920, BY C. V. MOSBY COMPANY
+
+
+ _Press of
+ C. V. Mosby Company
+ St. Louis_
+
+
+ TO
+
+ MY MOTHER
+
+ THIS VOLUME IS AFFECTIONATELY
+
+ DEDICATED
+
+
+
+
+PREFACE TO THIRD EDITION
+
+
+Several years have elapsed since the appearance of the second edition of
+this book. During this time there has been considerable experimentation
+and much writing on arteriosclerosis. The total of all work has not been
+to add very much to our knowledge of the etiology of arterial
+degeneration. Points of view and opinions change from time to time. It
+is so with arteriosclerosis. In this edition arteriosclerosis is not
+regarded as a disease with a definite etiologic factor. Rather it is
+looked upon as a degenerative process affecting the arteries following a
+variety of causes more or less ill defined. It is not considered a true
+disease. Possibly syphilitic arteritis may be viewed as an entity, the
+cause is known and the lesions are characteristic.
+
+Much new material and many new figures have been added to this edition.
+Some rearranging has been done. The chapter on Blood Pressure has been
+much expanded and some original observations have been included. The
+literature has been selected rather than indiscriminately quoted. Much
+that is written on the subject is of little value.
+
+It has always seemed to the author that there is not enough of the
+personal element in medical writings. At the risk of being severely
+criticized, he has attempted to make this book represent largely his own
+ideas, only here and there quoting from the literature.
+
+New chapters on Cardiac Irregularities Associated with Arteriosclerosis,
+and Blood Pressure in Its Clinical Application have been added.
+
+The fact that the book has passed through two editions is very
+gratifying and seems to show that it has met with favor. The author
+takes this opportunity of thanking those who have loaned him
+illustrations. Wherever figures are borrowed due credit is given.
+
+It is hoped that the kind of reception accorded to the first and second
+editions will also not be withheld from this present edition.
+
+ LOUIS M. WARFIELD.
+
+ Milwaukee, Wisc.
+
+
+
+
+PREFACE TO THE SECOND EDITION
+
+
+In this second edition so many changes and additions have been made that
+the book is practically a new one. All the chapters which were in the
+previous edition have been carefully revised. Two chapters, "Pathology"
+and "Physiology," have been completely rewritten and brought up to date.
+It was thought best to add some references for those who had interest
+enough to pursue the subject further. These references have been
+selected on account of the readiness with which they may be procured in
+any library, public or private. Two new chapters have been added--one on
+"The Physical Examination of the Heart and Arteries," the other on
+"Arteriosclerosis in Its Relation to Life Insurance," and it is hoped
+that these will add to the practical value of the book.
+
+Arteriosclerosis can scarcely be considered apart from blood pressure,
+and in the view expressed within, with which some may not concur, high
+tension is considered to be a large factor in the production of
+arteriosclerosis. As the data on blood pressure have increased, the
+importance of it has become more evident. The chapter on "Blood
+Pressure" has been wholly rewritten, expanded so as to give a
+comprehensive grasp of the essential features, and several illustrations
+have been added in order to elucidate the text more fully. The chief
+objects in view were to make clear to the physician the technique and
+the necessity for estimating both systolic and diastolic pressures.
+
+The author is grateful for the kindly reception accorded the first
+edition. No one is more keenly aware of the imperfections than he. The
+necessity for a second edition is taken to mean that the book has found
+a place for itself and has been of use to some.
+
+The author hopes that this new edition will fulfill adequately the
+purpose for which he prepared the book--namely, as a practical guide to
+the knowledge and appreciation of a most important and exceedingly
+common disease.
+
+ LOUIS M. WARFIELD.
+
+ Milwaukee, May, 1912.
+
+
+
+
+PREFACE TO THE FIRST EDITION
+
+
+It is hoped that this small volume may fill a want in the already
+crowded field of medical monographs. The author has endeavored to give
+to the general practitioner a readable, authoritative essay on a disease
+which is especially an outcome of modern civilization. To that end all
+the available literature has been freely consulted, and the newest
+results of experimental research and the recent ideas of leading
+clinicians have been summarized. The author has supplemented these with
+results from his own experience, but has thought it best not to burden
+the contents with case histories.
+
+The stress and strain of our daily life has, as one of its consequences,
+early arterial degeneration. There can be no doubt that arterial disease
+in the comparatively young is more frequent than it was twenty-five
+years ago, and that the mortality from diseases directly dependent on
+arteriosclerotic changes is increasing. Fortunately, the almost
+universal habit of getting out of doors whenever possible, and the
+revival of interest in athletics for persons of all ages, have to some
+extent counteracted the tendency to early decay. Nevertheless, the
+actual average prolongation of life is more probably due to the very
+great reduction in infant mortality and in deaths from infectious and
+communicable diseases.
+
+The wear and tear on the human organism in our modern way of living is
+excessive. Hard work, worry, and high living all predispose to
+degenerative changes in the arteries, and so bring on premature old age.
+The author has tried to emphasize this by laying stress on the
+prevention of arteriosclerosis rather than on the treatment of the fully
+developed disease.
+
+No bibliography is given, as this is not intended as a reference book,
+but rather as a guide to a better appreciation and understanding of a
+most important subject. It has been difficult to keep from wandering off
+into full discussions of conditions incident to and accompanied by
+arteriosclerosis, but, in order to be clear in his statements and
+complete in his descriptions, the author has to invade the fields of
+heart disease, kidney disease, brain disease, etc. It is hoped, however,
+that these excursions will serve to show how intimately disease of the
+arteries is bound up with diseases of all the organs and tissues of the
+body.
+
+Some authors have been named when their opinions have been given. Thanks
+are extended also to many others to whom the writer is indebted, but of
+whom no individual mention has been made.
+
+The author also takes this opportunity of expressing his appreciation of
+the kindness of Dr. D. L. Harris, who took the microphotographs, and to
+the publishers for their unfailing courtesy and consideration.
+
+ LOUIS M. WARFIELD.
+
+ St. Louis, August, 1908.
+
+
+
+
+CONTENTS
+
+
+ PAGE
+
+ CHAPTER I
+
+ ANATOMY 25
+
+ Introduction, 25; Definition, 26; General Structure of
+ the Arteries, 27; Arteries, 29; Veins, 30; Capillaries, 31.
+
+ CHAPTER II
+
+ PATHOLOGY 32
+
+ Syphilitic Aortitis, 44; Experimental Arteriosclerosis, 50;
+ Arteriosclerosis of the Pulmonary Arteries, 63; Sclerosis
+ of the Veins, 64.
+
+ CHAPTER III
+
+ PHYSIOLOGY OF THE CIRCULATION 65
+
+ Blood Pressure, 68; Blood Pressure Instruments, 70; Technic,
+ 80; Arterial Pressure, 85; Normal Pressure Variations, 88;
+ The Auscultatory Blood Pressure Phenomenon, 90; The Maximum
+ and Minimum Pressures, 94; Relative Importance of the
+ Systolic and Diastolic Pressures, 97; Pulse Pressure, 100;
+ Blood Pressure Variations, 102; Hypertension, 106;
+ Hypotension, 117; The Pulse, 123; The Venous Pulse, 123;
+ The Electrocardiogram, 126.
+
+ CHAPTER IV
+
+ IMPORTANT CARDIAC IRREGULARITIES ASSOCIATED WITH
+ ARTERIOSCLEROSIS 131
+
+ Auricular Flutter, 131; Auricular Fibrillation, 133;
+ Ventricular Fibrillation, 138; Extrasystole, 138;
+ Heart Block, 140.
+
+ CHAPTER V
+
+ BLOOD PRESSURE IN ITS CLINICAL APPLICATIONS 147
+
+ Blood Pressure in Surgery, 147; Head Injuries, 148; Shock
+ and Hemorrhage, 148; Blood Pressure in Obstetrics, 152;
+ Infectious Diseases, 153; Valvular Heart Disease, 155;
+ Kidney Disease, 155; Other Diseases, Liver, Spleen,
+ Abdomen, etc., 156.
+
+ CHAPTER VI
+
+ ETIOLOGY 157
+
+ Congenital Form, 157; Acquired Form, 159; Hypertension,
+ 159; Age, Sex, Race, 161; Occupation, 162; Food Poisons,
+ 163; Infectious Diseases, 163; Syphilis, 165; Chronic
+ Drug Intoxications, 166; Overeating, 167; Mental Strain,
+ 168; Muscular Overwork, 169; Renal Disease, 169; Ductless
+ Glands, 171.
+
+ CHAPTER VII
+
+ THE PHYSICAL EXAMINATION OF THE HEART AND ARTERIES 172
+
+ Heart Boundaries, 172; Percussion, 174; Auscultation,
+ 176; The Examination of the Arteries, 177; Estimation
+ of Blood Pressure, 179; Palpation, 180; Precautions When
+ Estimating Blood Pressure, 181; The Value of Blood
+ Pressure, 181.
+
+ CHAPTER VIII
+
+ SYMPTOMS AND PHYSICAL SIGNS 183
+
+ General, 183; Hypertension, 185; The Heart, 188; Palpable
+ Arteries, 189; Ocular Signs and Symptoms, 190; Nervous
+ Symptoms, 191.
+
+ CHAPTER IX
+
+ SYMPTOMS AND PHYSICAL SIGNS 194
+
+ Special, 194; Cardiac, 195; Renal, 199; Abdominal or
+ Visceral, 201; Cerebral, 203; Spinal, 205; Local or
+ Peripheral, 207; Pulmonary Artery, 209.
+
+ CHAPTER X
+
+ DIAGNOSIS 210
+
+ Early Diagnosis, 210; Differential Diagnosis, 215;
+ Diseases in Which Arteriosclerosis is Commonly Found, 216.
+
+ CHAPTER XI
+
+ PROGNOSIS 218
+
+ CHAPTER XII
+
+ PROPHYLAXIS 224
+
+ CHAPTER XIII
+
+ TREATMENT 229
+
+ Hygienic Treatment, 230; Balneotherapy, 233; Personal
+ Habits, 234; Dietetic Treatment, 235; Medicinal, 238;
+ Symptomatic Treatment, 245.
+
+ CHAPTER XIV
+
+ ARTERIOSCLEROSIS IN ITS RELATION TO LIFE INSURANCE 249
+
+ CHAPTER XV
+
+ PRACTICAL SUGGESTIONS 256
+
+
+
+
+ILLUSTRATIONS
+
+
+ FIG. PAGE
+
+ 1. Cross section of a large artery 28
+
+ 2. Cross section of a coronary artery 36
+
+ 3. Arteriosclerosis of the thoracic and abdominal aorta 39
+
+ 4. Arteriosclerosis of the arch of the aorta 40
+
+ 5. Normal aorta 41
+
+ 6. Radiogram showing calcification of both radial and ulnar
+ arteries 42
+
+ 7. Syphilitic aortitis of long standing 44
+
+ 8. Diagrammatic representation of strain hypertrophy 48
+
+ 9. Strain hypertrophy 49
+
+ 10. Cross section of small artery in the mesentery 56
+
+ 11. Enormous hypertrophy of left ventricle 58
+
+ 12. Aortic incompetence with hypertrophy and dilatation of
+ left ventricle 61
+
+ 13. Cook's modification of Riva-Rocci's blood pressure
+ instrument 72
+
+ 14. Stanton's sphygmomanometer 73
+
+ 15. The Erlanger sphygmomanometer with the Hirschfelder
+ attachments 74
+
+ 16. Desk model Baumanometer 75
+
+ 17. Faught blood pressure instrument 76
+
+ 18. Rogers' "Tycos" dial sphygmomanometer 77
+
+ 19. Detail of the dial in the "Tycos" instrument 78
+
+ 20. Faught dial instrument 79
+
+ 21. Detail of the dial of the Faught instrument 79
+
+ 22. The Sanborn instrument 80
+
+ 23. Method of taking blood pressure with a patient in sitting
+ position 81
+
+ 24. Method of taking blood pressure with patient lying down 82
+
+ 25. Observation by the auscultatory method and a mercury
+ instrument 84
+
+ 26. Observation by the auscultatory method and a dial instrument 85
+
+ 27. Schema to illustrate decrease in pressure 86
+
+ 28. Chart showing the normal limits of variation in systolic
+ blood pressure 89
+
+ 29. Tracing of auscultatory phenomena 94
+
+ 30. Tracing of auscultatory phenomena 95
+
+ 31. Clinical determination of diastolic pressure, fast drum 96
+
+ 32. Clinical determination of diastolic pressure, slow drum 96
+
+ 33. Venous blood pressure instrument 121
+
+ 34. New venous pressure instrument 122
+
+ 35. Events in the cardiac cycle 124
+
+ 36. Simultaneous tracings of the jugular and carotid pulses 125
+
+ 37. Jugular and carotid tracings 125
+
+ 38. Right side of the heart showing distribution of the
+ two vagus nerves 127
+
+ 39. Normal electrocardiogram 128
+
+ 40. Auricular flutter 132
+
+ 41. Auricular fibrillation 134
+
+ 42. Auricular fibrillation 134
+
+ 43. Pulse deficit 135
+
+ 44. Ventricular fibrillation 137
+
+ 45. Auricular extrasystoles 139
+
+ 46. Ventricular extrasystole 139
+
+ 47. Delayed conduction 141
+
+ 48. Partial heart block 141
+
+ 49. Complete heart block 142
+
+ 50. Alternating periods of sinus rhythm and
+ auriculoventricular rhythm 144
+
+ 51. Auriculoventricular or "nodal" rhythm 144
+
+ 52. Influence of mechanical pressure on the right vagus nerve 144
+
+ 53. Schematic distribution of right and left vagus 145
+
+ 54. Blood pressure record from a normal reaction to ether 149
+
+ 55. Chart showing the method of recording blood pressure
+ during an operation 150
+
+ 56. Method of using blood pressure instrument during operation 151
+
+ 57. Finger-tip palpation of the radial artery 178
+
+ 58. Finger-tip palpation of the radial artery 178
+
+ 59. Aneurysm of the heart wall 196
+
+ 60. Large aneurysm of the aorta eroding the sternum 198
+
+
+
+
+ARTERIOSCLEROSIS AND HYPERTENSION
+
+
+
+
+CHAPTER I
+
+ANATOMY
+
+
+With the increased complexity of our modern life comes increased wear
+and tear on the human organism. "A man is as old as his arteries" is an
+old dictum, and, like many proverbs, the application to mankind today
+is, if anything, more pertinent than it was when the saying was first
+uttered. Notwithstanding the fact that the average age of mankind at
+death has been materially lengthened--the increase in years amounting to
+fourteen in the past one hundred years of history--clinicians and
+pathologists are agreed that the arterial degeneration known as
+arteriosclerosis is present to an alarming extent in persons over forty
+years of age. Figures in all vital statistics have shown us that all
+affections of the circulatory and renal systems are definitely on the
+increase. "Arterial diseases of various kinds, atheroma, aneurysm, etc.,
+caused 15,685 deaths in 1915, or 23.3 per 100,000. This rate, although
+somewhat lower than the corresponding ones for 1912 and 1913, is higher
+than that for 1914, and is very much higher than that for 1900, which
+was 6.1."
+
+The great group of cases of which cardiac incompetence, aneurysm,
+cerebral apoplexy, chronic nephritis, emphysema, and chronic bronchitis
+are the most frequent and important appear as terminal events in which
+arteriosclerosis has probably played an important part.
+
+Thus, in the sense in which we speak of tuberculosis or pneumonia as a
+distinct disease, we can not so designate the diseased condition of the
+arteries.
+
+Arteriosclerosis is not a disease =sui generis=. It is best viewed as a
+degeneration of the coats of the arteries, both large and small
+resulting in several different more or less distinct types.
+
+These types blend one into the other and in the same patient all types
+may be found. Thus the sclerosis of the arteries is the result of a
+variety of causes, none of which is definitely known in the sense of a
+bacterial disease. As we shall see later, one type of arteriosclerosis
+has a special pathology and etiology, the syphilitic arterial changes.
+
+Bearing in mind that arteriosclerosis (called by some "arteriocapillary
+fibrosis," by others "atherosclerosis") is not a true disease, it may,
+for convenience be defined as a chronic disease of the arteries and
+arterioles, characterized anatomically by increase or decrease of the
+thickness of the walls of the blood vessels, the initial lesion being a
+weakening of the middle layer caused by various toxic or mechanical
+agencies. This weakness of the media leads to secondary effects, which
+include hypertrophy or atrophy of the inner layer--and not infrequently
+hypertrophy of the outer layer--connective tissue formation and
+calcification in the vessels, and the formation of minute aneurysms
+along them. The term arteriocapillary fibrosis has a broader meaning,
+but is a cumbersome phrase, and conveys the idea that the capillary
+changes are an essential feature of the process, whereas these are for
+the most part secondary to the changes in the arteries. The veins do not
+always escape in the general morbid process, and when these are affected
+the whole condition is sometimes called vascular sclerosis or
+angiosclerosis.
+
+Upon the anatomical structure of the arteries depends, as a rule, the
+character and extent of the arteriosclerotic lesions. For the clear
+comprehension of the process, it is necessary to keep in mind the
+essential histological differences between the aorta and the larger and
+smaller branches of the arterial tree.
+
+The vascular system is often likened to a central pump, from which
+emanates a closed system of tubes, beginning with one large
+distributing pipe, which gives rise to a series of tubes, whose number
+is constantly increasing at the same time that their caliber is
+decreasing in size. From the smallest of these tubes, larger and larger
+vessels collect the flowing blood, until, at the pump, two large trunks
+of approximately the same area as the one large distributing trunk empty
+the blood into the heart, thus completing the circle. This is but a
+rough illustration, and, while possibly useful, takes into account none
+of the vital forces which are constantly controlling every part of the
+distributing system.
+
+
+General Structure of the Arteries
+
+The aorta and its branches are highly elastic tubes, having a smooth,
+glistening inner surface. When the arteries are cut open, they present a
+yellowish appearance, due to the large quantity of elastic tissue
+contained in the walls. The elasticity is practically perfect, being
+both longitudinal and transverse. The essential portion of any blood
+vessel is the endothelial tube, composed of flat cells cemented together
+by intercellular substance and having no stomata between the cells. This
+tube is reinforced in different ways by connective tissue, smooth muscle
+fibers, and fibroelastic tissue. Although the gradations from the larger
+to the smaller arteries and from these to the capillaries and veins are
+almost insensible, yet particular arteries present structural characters
+sufficiently marked to admit of histological differentiation.
+
+The whole vascular system, including the heart, has an endothelial
+lining, which may constitute a distinct inner coat, the tunica intima,
+or may be without coverings, as in the case of the capillaries. The
+intima (Fig. 1) consists typically of endothelium, reinforced by a
+variable amount of fibroelastic tissue, in which the elastic fibers
+predominate. The tunica media is composed of intermingled bundles of
+elastic tissue, smooth muscle fibers, and some fibrous tissue. The
+adventitia or outer coat is exceedingly tough. It is usually thinner
+than the media, and is composed of fibroelastic tissue. This division
+into three coats is, however, somewhat arbitrary, as in the larger
+arteries particularly it is difficult to discover any distinct
+separation into layers.
+
+[Illustration: Fig. 1.--Cross section of a large artery showing the
+division into the three coats; intima, media, adventitia. The intima is
+a thin line composed of endothelial cells. The wavy elastic lamina is
+well seen. The thick middle coat is composed of muscle fibers and
+fibroelastic tissue. The loose tissue on the outer (lower portion of
+cut) side of the media is the adventitia. (Microphotograph, highly
+magnified.)]
+
+The muscular layer varies from single scattered cells, in the
+arterioles, to bands of fibers making up the body of the vessel in the
+medium-sized arteries and veins.
+
+There is elastic tissue in all but the smallest arteries, and it is also
+found in some veins. It varies in amount from a loose network to dense
+membranes. In the intima of the larger arteries the elastic tissue
+occurs as sheets, which under the microscope appear perforated and
+pitted, the so-called fenestrated membrane of Henle.
+
+The nutrient vessels of the arteries and veins, the vasa vasorum, are
+present in all the vessels except those less than one millimeter in
+diameter. The vasa vasorum course in the external coat and send
+capillaries into the media, supplying the outer portion of the coat and
+the externa with nutritive material. The nutrition of the intima and
+inner portion of the media is obtained from the blood circulating
+through the vessel. Lymphatics and nerves are also present in the middle
+and outer layers of the vessels.
+
+
+Arteries
+
+The structure of the arteries varies notably, depending upon the size of
+the vessel. A cross section of the thoracic aorta reveals a dense
+network of elastic fibers, occupying practically all of the space
+between the single layer of endothelial cells and the loose elastic and
+connective tissue network of the outer layer. Smooth muscle fibers are
+seen in the middle coat, but, in comparison with the mass of elastic
+tissue, they appear to have only a limited function.
+
+In a cross section of the radial artery one sees a wavy outline of
+intima, caused by the endothelium following the corrugations of the
+elastica. The endothelium is seen as a delicate line, in which a few
+nuclei are visible. The media is comparatively thick, and is composed of
+muscle cells, arranged in flat bundles, and plates of elastic tissue.
+Between the media and the externa the elastic tissue is somewhat
+condensed to form the external elastic membrane. The adventitia varies
+much in thickness, being better developed in the medium-sized than in
+the large arteries. It is composed of fibrous tissue mixed with elastic
+fibers.
+
+"Followed toward the capillaries, the coats of the artery gradually
+diminish in thickness, the endothelium resting directly upon the
+internal elastic membrane so long as the latter persists, and afterward
+on the rapidly attenuating media. The elastica becomes progressively
+reduced until it entirely disappears from the middle coat, which then
+becomes a purely muscular tunic, and, before the capillary is reached,
+is reduced to a single layer of muscle cells. In the precapillary
+arterioles the muscle no longer forms a continuous layer, but is
+represented by groups of fiber cells that partially wrap around the
+vessel, and at last are replaced by isolated elements. After the
+disappearance of the muscle cells the blood vessel has become a true
+capillary. The adventitia shares in the general reduction, and gradually
+diminishes in thickness until, in the smallest arteries, it consists of
+only a few fibroelastic strands outside the muscle cells." (Piersol's
+Anatomy.)
+
+The large arteries differ from those of medium size mainly in the fact
+that there is no sharp line of demarcation between the intima and the
+media. There is also much more elastic tissue distributed in firm
+bundles throughout the media, and there are fewer muscle fibers, giving
+a more compact appearance to the artery as seen in cross section. The
+predominance of elastic tissue permits of great distention by the blood
+forced into the artery at every heartbeat, the caliber of the tube being
+less markedly under the control of the vasomotor nerves than is the case
+in the small arteries, where the muscle tissue is relatively more
+developed. The adventitia of the large arteries is strong and firm, and
+is made up of interlacing fibroelastic tissue, of which some of the
+bundles are arranged longitudinally.
+
+
+Veins
+
+The walls of the veins are thinner than those of the arteries; they
+contain much less elastic and muscular tissue, and are, therefore, more
+flaccid and less contractile. Many veins, particularly those of the
+extremities, are provided with cup-like valves opening toward the heart.
+These valves, when closed, prevent the return of the blood to the
+periphery and distribute the static pressure of the blood column. The
+bulgings caused by the valves may be seen in the superficial veins of
+the arm and leg. There are no valves in the veins of the neck, where
+there is no necessity for such a protective mechanism, gravity sufficing
+to drain the venous blood from the cranial cavity.
+
+
+Capillaries
+
+These are endothelial tubes in the substance of the organs, the tissue
+of the organ giving them the necessary support. They are the final
+subdivisions of the blood vessels, and the vast capillary area offers
+the greatest amount of resistance to the blood flow, thus serving to
+slow the blood stream and allowing time for nutritive substances or
+waste products to pass from and to the blood. Usually the capillaries
+are arranged in the form of a network, the channels in any one tissue
+being of nearly uniform size, and the closeness of the mesh depending
+upon the organ.
+
+As far back as 1865, Stricker observed contraction of the capillaries.
+This observation was apparently forgotten until revived again by Krogh
+recently. The latter finds that the capillaries are formed of cells
+which are arranged in strands encircling the vessel. The capillaries are
+rarely longer than 1 mm., and, according to Krogh, are capable of
+enormous dilatation.
+
+The rate of flow through any capillary area is very inconstant, and the
+usual explanation has been that the capillaries were endothelial tubes
+the blood flow of which was dependent upon the contraction or dilatation
+of the terminal arterioles. The actual fact that in an observed
+capillary area some capillaries are empty renders the above explanation
+untenable. The color of a tissue depends upon the state of filling of
+the capillaries with blood.
+
+It would seem that all the evidence now leads us to believe that the
+capillaries themselves are contractile and it is even possible that they
+may be under vasomotor control. If the anatomic structure as stated
+above, is correct, it would take but a slight contraction of the
+encircling cell to shut off completely the capillary. When the enormous
+capillary bed is considered, it is not inconceivable that circulating
+poisons may act on large areas and produce a true capillary resistance
+to the onflow of blood which might express itself, if long continued, in
+actual hypertrophy of the heart.
+
+
+
+
+CHAPTER II
+
+PATHOLOGY
+
+
+The whole subject of the pathology of arteriosclerosis has been much
+enriched by the study of the experimental lesions produced by various
+drugs and microorganisms upon the aortas of rabbits. Simple atheroma
+must not be confused with the lesions of arteriosclerosis. The small
+whitish or yellowish plaques so frequently seen on the aorta and its
+main branches, may occur at any age, and have seemingly no great
+significance. Such plaques may grow to the size of a dime or larger, and
+even become eroded. They represent fatty degeneration of the intima
+which, at times, has no demonstrable cause; at times follows in the
+course of various diseases, and undoubtedly is due to disturbances of
+nutrition in the intima. Except for the remote danger of clot formation
+on the uneven or eroded spot, these places are of no special
+significance, and are not to be confused with the atheroma of nodular
+sclerosis.
+
+The lesions of arteriosclerosis are of a different character. It has
+been customary to differentiate three types: (1) nodular; (2) diffuse;
+(3) senile. It must be understood that this is not a classification of
+distinct types. As a rule in advanced arteriosclerosis, lesions
+representing all types and all grades are found. The nodular type,
+however, may occur in the aorta alone, the branches remaining free. This
+is most often found in syphilitic sclerosis where the lesion is confined
+to the ascending portion of the arch of the aorta.
+
+The retrogressive changes of advancing years can not be rightly termed
+disease, yet it becomes necessary to regard them as such, for the senile
+changes, as we shall see, may be but the advanced stages of true
+arteriosclerosis. Much depends on the nature of the arterial tissue and
+much on the factors at work tending to injure the tissue. A man of
+forty years may therefore have the calcified, pipe stem arteries of a
+man of eighty. Our parents determine, to great extent, the kind of
+tissue with which we start life. The arteries are elastic tubes capable
+of much stretching and abuse. In the aorta and large branches there is
+much elastic tissue and relatively little muscle. When the vessels have
+reached the organs, they are found to be structurally changed in that
+there is in them a relatively small amount of elastic tissue but a great
+deal of smooth muscle. This is a provision of nature to increase or
+decrease the supply of blood at any point or points.
+
+The aorta and the large branches are distributing tubes only. It is
+after all in the arterioles and smaller arteries that the lesions of
+arteriosclerosis do the most damage. A point to be emphasized is that
+the whole arterial system is rarely, if ever, attacked uniformly. That
+is, there may be a marked degree of sclerosis in the aorta and coronary
+arteries with very little, if any, change in the radials. On the
+contrary, a few peripheral arteries only may be the seat of disease. A
+case in point was seen at autopsy in which the aorta in its entirety and
+all the large peripheral branches were absolutely smooth. In the brain,
+however, the arteries were tortuous, hard, and were studded with miliary
+aneurysms. It is not possible to judge accurately the state of the whole
+arterial system by the stage of the lesion in any one artery; but on the
+whole one may say that an undue thickening of the radial artery
+indicates analogous changes in the mesenteric arteries and in the aorta.
+
+So far as the anatomical lesions in the aorta and branches are
+concerned, there is much uniformity even though the etiologic factors
+have been diverse. The only difference is one of extent. To Thoma we owe
+the first careful work on arteriosclerosis. He regarded the lesion in
+arteriosclerosis as one situated primarily in the media; there is a lack
+of resistance in this coat. His views are now chiefly of historical
+interest. As the author understands him, he considered a rupture in the
+media to be the cause of a local widening and consequently the blood
+could not be distributed evenly to the organ which was supplied by the
+diseased artery or arteries. Moreover, there was danger of a rupture at
+the weak spot unless this were strengthened. It was essential for the
+even distribution of blood that the lumen be restored to its former
+size. Nature's method of repair was a hypertrophy of the subintimal
+connective tissue and the formation of a nodule at that point. The
+thickening was compensatory, resulting in the establishment of the
+normal caliber of the vessel. Thoma showed that by injecting an aorta in
+the subject of such changes, with paraffin at a pressure of 160 mm. of
+mercury, these projections disappeared and the muscle bulged externally.
+He recognized the fact that the character of the artery changed as the
+years passed, and to this form he gave the name, primary
+arteriosclerosis. To the group of cases caused by various poisonous
+agents, or following high peripheral resistance and consequent high
+pressure, he gave the name, secondary arteriosclerosis. This is a useful
+but not essential division, as the changes which age and high tension
+produce may not be different from those produced in much younger persons
+by some circulating poison. And most important to bear in mind,
+octogenarians may have soft, elastic arteries.
+
+As the body ages, certain changes usually take place in the arteries
+leading to thickening and inelasticity of their walls. This is a normal
+change, and in estimating the palpable thickening of an artery, such as
+the radial, the age of the individual must always be considered.
+
+Thayer and Fabyan, in an examination of the radial artery from birth to
+old age, found that, in general, the artery strengthens itself, as more
+strain is thrown upon it, by new elastica in the intima and connective
+tissue in the media and adventitia. Up to the third decade there is
+only a strengthening of the media and adventitia. During the third and
+fourth decades there is also distinct connective tissue thickening in
+the intima. "In other words, the strain has begun to tell upon the
+vessel wall, and the yielding tube fortifies itself by the connective
+tissue thickening of the intima and to a lesser extent of the media." By
+the fifth decade the connective tissue deposits in the intima are
+marked, there is an increase of fibrous tissue upon the medial side of
+the intima and, in lesser degree, throughout the media. "Finally, in
+these sclerotic vessels degenerative changes set in, which are somewhat
+different from those seen in the larger arteries, consisting, as they
+do, of local areas of coagulation necrosis with calcification,
+especially marked in the deep layers of the connective tissue
+thickenings of the intima, and in the muscle fibers of the media,
+particularly opposite these points. These changes may ... go on to
+actual bone formation." The mesenteric artery differs in some respects
+from the radial, but in the main, the changes brought about by age are
+the same. Thayer and Fabyan note two striking points of difference: "(1)
+calcification is apparently much less frequent than in the radials; (2)
+in several cases plaques were seen with fatty softening of the deeper
+layers of the intima and superficial proliferation--a picture which we
+have never seen in the radial." (See Fig. 2.)
+
+[Illustration: Fig. 2.--Cross-section of a coronary artery, x50, showing
+nodular sclerosis. Note the heaping up of cells in the intima, the
+fracture of the elastica, and the destruction of the media beneath the
+nodule. The primary lesion evidently was in the media. The thickened
+intima is the effort on the part of nature to heal the breach. At such
+places as shown here aneurysms may form. (Microphotograph.)]
+
+Aschoff's studies of the aorta show that, "in infancy the elastic laminae
+of the media stand out sharply defined, well separated from each other
+by the muscle layers, which are well developed.... From childhood there
+is to be observed a slowly progressive increase in the elastic elements
+of the media. Not only do the individual lamellae seen in cross-sections
+become thicker, but also they afford an increasing number of fine
+secondary filaments feathering off from these and crossing the muscle
+layer, so that now they are no longer sharply defined, but more ragged
+upon cross-section. This progressive increase attains its maximum at or
+about the age of thirty-five, and from now on for the next fifteen
+years the condition is relatively stationary. After fifty there is to be
+observed a slowly progressive atrophy of the elastica. The media becomes
+obviously thinner and presumably weaker." (Adami.) It has also been
+found (Klotz) that after the age of thirty-five, the muscle of the media
+begins to exhibit fatty degeneration which after fifty years is well
+marked. The fatty degeneration may then give place to a calcareous
+infiltration or the fibers may undergo complete absorption. It would
+appear that the thinning of the aortic media is due not so much to the
+atrophy of the elastic tissue as to that of the muscle tissue. The
+elastic tissue does lose its specific property and the artery thus
+becomes practically a connective tissue tube.
+
+Scheel has made very careful measurements of the ascending, the
+thoracic, and the abdominal aorta, and the pulmonary artery. He found
+that from birth to sixty years, the aorta became progressively wider and
+lost its elasticity. The pulmonary changed little, if at all, after
+thirty to forty years, and where before it was wider than the aorta, it
+now was found to be smaller. In chronic nephritis both were widened. The
+continuous increase of width and length of the aorta stands in reverse
+relationship to the elasticity of its walls.
+
+Although the division of the lesions into nodular, diffuse, and senile
+has been the usual one, it is better to separate three groups into (1)
+nodular, (2) diffuse or senile, and (3) syphilitic. There is more known
+about the histology of the syphilitic form and the lesions which consist
+of puckerings and scars seen on opening an aorta just above the valves,
+and on the ascending portion of the arch are characteristic. A
+macroscopic examination suffices in most cases for a definite diagnosis.
+
+In the nodular form the lesions are found on the aorta and large
+branches particularly at or near the orifices of branching vessels.
+These nodules may increase in size, forming rather large, slightly
+raised plaques of yellowish-white color. They are, as a rule,
+irregularly scattered throughout the aorta and branches and tend to be
+more numerous and larger in the abdominal aorta. The initial lesion is
+in the media, consisting of an actual dissolution of this coat with
+rupture of the elastic fibers and infiltration with small round cells.
+There is thus a weak spot in the artery. Hypertrophy of the intimal
+cells takes place, layer upon layer being added in an attempt to
+strengthen the vessel at the injured place. Coincidently with this,
+there is thickening by a connective tissue growth in the adventitia. The
+process begins, at least in syphilis, around the terminals of the vasa
+vasorum. It will be recalled that the blood supply of the inner portion
+of the media comes from within the vessel itself. As the intimal growth
+increases, the blood supply is cut off. The inevitable result is
+softening of the portion farthest from the lumen of the vessel. As a
+rule there has been a sufficient growth of connective tissue in the
+media and adventitia to repair the damage done to the media. This
+softening and dissolution gives rise to a granular debris composed of
+degenerated cells and fat. This is the so-called atheromatous abscess.
+There are no leucocytes as in ordinary pus. These "abscesses" are
+frequent and in rupturing leave open ulcers with smooth bases, the
+atheromatous ulcer. A further change which often takes place is
+calcification of the bases of the ulcers and calcification of the
+softened spots before rupture takes place. This only occurs in advanced
+cases. (See Fig. 3.)
+
+[Illustration: Fig. 3.--Arteriosclerosis of the thoracic and abdominal
+aorta, showing irregular nodules, atheromatous plaques, denudation of
+the intima, thin plates of bone scattered throughout with spicules
+extending into the lumen of the vessel. Note the contraction of the
+openings of the large branches, the rough appearance of the aorta and
+the greater degree of sclerosis of the upper two-thirds, i. e., of the
+aorta above the diaphragm. This aorta in the recent state was much
+thickened and almost inelastic.]
+
+[Illustration: Fig. 4.--Arteriosclerosis of the arch of the aorta.
+Numerous calcified plaques, thickening and curling of the aortic valves,
+giving rise to insufficiency of the aortic valves. The aortic ring is
+rigid and not much dilated. (Milwaukee County Hospital.)]
+
+[Illustration: Fig. 5.--Normal aorta. Compare with Fig. 3. Note the
+perfectly smooth, glossy appearance of the intima. The openings of all
+the intercostal arteries are distinctly seen. In the recent state this
+artery was highly elastic, capable of much stretching both transversely
+and longitudinally.]
+
+Rather contrary to what one would expect, there are no new capillaries
+advancing from the media to the intima in the nodular form of
+arteriosclerosis, consequently there is no granulation tissue to heal
+and leave scars. It must be borne in mind that these changes rarely, if
+ever, are the only ones found throughout the arterial system.
+Nevertheless, the manifold changes, as will be shown within, appear to
+be but stages of one primary process.
+
+The character of the changes which are known as diffuse arteriosclerosis
+seems to have, at first sight, little in common with those of the
+nodular sclerosis. The aorta may or may not have plaques of nodular
+sclerosis, while the arteries, such as the radial or temporal, may be
+beaded or pipe stem in hardness. In spite of these far advanced
+peripheral lesions the aorta may appear smooth but it is markedly
+dilated, particularly the thoracic portion, it is noticeably thinned
+even on macroscopic examination, it has elongated as evidenced by its
+slight tortuosity, and it has lost the greater part of its elasticity.
+The abdominal aorta is not so extensively affected, although this, too,
+shows some elongation and slight thinning. This is considered by some
+pathologists to be the uncomplicated form of the so-called senile
+arteriosclerosis. It is more of the nature of a degenerative change, it
+is true, but, as will be shown later, it has its beginnings, at times,
+in comparatively young persons and its etiology is not simple. This
+type has been studied most carefully by Moenckeberg, who showed that on
+the large branches of the aorta there were depressions due to a
+degeneration of the middle coat. These depressions encircled the vessel
+to a greater or lesser extent, causing small bulgings at such places
+and giving to the vessel a beaded appearance. On viewing such an artery
+held to the light, the sacculated spots are seen to be much thinner than
+the contiguous normal artery. Associated with such changes in the aorta
+and large branches is marked sclerosis of the smaller arteries. Intimal
+fibrosis is common, together with hypertrophy and fibrosis of the middle
+coat. Not infrequently periarterial thickening is also seen.
+Calcification of the media is found and is said to be preceded by
+hypertrophy of the middle coat.
+
+Pure cases of this, the so-called Moenckeberg type, are seen but seldom.
+Most commonly there are nodules and plaques in the aorta and large
+branches together with thinning and sacculation of other portions of the
+vessels' walls. While the two processes appear at a glance to be so
+different from each other, it is possible for them to have a common
+origin. The initial lesion is in the media but the resulting sclerotic
+changes depend upon the kind of vessel, the strength of the coats, the
+pressure in the vessel, and other causes.
+
+Thus the sclerosis of the radials of such an extent that these arteries
+are easily palpable, appears to be a different process from that of the
+sclerosis in the aorta, yet fundamentally it is the same. The difference
+lies in the anatomic structure of the two vessels, and possibly also in
+the degree of stretching and strain to which the vessels are subjected
+at every heart beat. In the radial artery the media as usual is affected
+first. The muscle cells undergo degeneration and either marked
+thickening takes place or sacculation results, depending upon the
+severity of the exciting cause. Calcification of the media is common.
+This occasionally takes the form of rings encircling the vessel, and
+gives to the examining finger the sensation of feeling a string of fine
+beads. There may be calcification of the subintimal tissue without
+deposits of lime salts in the media, but this is more commonly found in
+the larger arteries. When the calcification occurs in plates through the
+media, the well known pipe stem vessel is produced. (Fig. 6.)
+
+[Illustration: Fig. 6.--Radiogram of a man aged seventy-five, showing
+calcification of both radial and ulnar arteries.]
+
+The senile sclerosis found in old people is usually a combination of the
+Moenckeberg type in the large and medium-sized arteries, and the nodular
+type in the aorta, leading eventually to calcareous intimal deposits,
+and widened, elongated, inelastic aorta.
+
+
+=Syphilitic Aortitis=
+
+[Illustration: Fig. 7.--Syphilitic aortitis of long standing. The aortic
+valves are curled and thickened, the heart is enlarged and the cavity of
+the left ventricle is dilated. (Milwaukee County Hospital.)]
+
+The seat of election of the syphilitic poison is in the aorta just above
+the aortic valves, Fig. 7, and in the ascending portion of the arch.
+There are semitranslucent, hyaline-like plaques which have a tendency to
+form into groups and, instead of undergoing an atheromatous change as
+in the ordinary nodular form of arteriosclerosis, they are prone to scar
+formation with puckering, so that macroscopically the nature of the
+process may, as a rule, be readily diagnosed. Microscopically the
+process is found to be a subacute inflammation of the media, which has
+been called a mesaortitis. There is marked small celled infiltration
+around some of the branches of the vasa vasorum and there appears to be
+actual absorption of the tissue elements of the middle coat. This is
+accompanied by hypertrophy of the intimal tissue. There follows
+degeneration in the deeper portions of this new tissue and new
+capillaries are formed which have their origin in the inflammatory area
+in the media. As is everywhere the case throughout the body, granulation
+tissue in the process of healing contracts and forms scars. This
+explains the scar formation in the aorta. When the process is more
+acute, instead of there being a reparative attempt on the part of the
+intima, there is actual stretching of the wall at the weakened spot and
+there results an aneurysmal dilatation. =Spirochetae pallidae= have been
+found in the degenerated media and in small gummata which were situated
+beneath the intima. Within the past years it has been found that a large
+percentage of patients with cardiovascular disease give the Wassermann
+reaction. In cases of aortic insufficiency, the reaction is present in
+almost every case. This is in marked contrast to the cases of diffuse
+endocarditis where the reaction is rarely present.
+
+According to Adami the effects of syphilis upon the aorta are the
+following: (1) the primary disturbance is a granulomatous, inflammatory
+degeneration of the media; (2) this leads to a local giving way of the
+aorta; (3) if this be moderate it results in a strain hypertrophy of the
+intima and of the adventitia, with the development of a nodose intimal
+sclerosis; (4) if it be extreme, there results, on the contrary, an
+overstrain atrophy of the intima and aneurysm formation; (5) the intimal
+nodosities are here not of an inflammatory type and are nonvascular,
+although, with the progressive laying down of layer upon layer of
+connective tissue on the more intimal aspect of the intima, the earlier
+and deeper-placed layers of new tissue gain less and less nourishment,
+and so are liable to exhibit fatty degeneration and necrosis; (6) these
+products of necrosis exert a chemotactic influence upon the nearby
+vessels of the medial granulation tissue, with, as a result, (a) a
+secondary and late entrance of new vessels into the early and
+deeply-placed atheromatous area, (b) absorption of the necrotic
+products, (c) replacement by granulation tissue, (d) contraction of the
+granulation tissue, and (e) depression and scarring of the sclerotic
+nodules so characteristic of syphilitic sclerosis.
+
+In the smaller arteries and arterioles the arteriosclerotic process
+appears on superficial examination to be a different process from that
+in the aorta and large arteries, but the difference is only apparent. It
+will be recalled that there is relatively much more muscle tissue in the
+arterioles than in the large arteries. The size, of course, is much
+less. Large nodular plaques are not possible. The atheromatous
+degeneration is not marked. In the smaller muscular arteries is seen the
+intimal proliferation, the stretching of the Moenckeberg type, and the
+calcification of the media rather than the intima. The media is thinned
+beneath the marked intimal proliferation so that the artery exhibits
+translucent areas when held to the light. Again, there is seen
+degeneration of the muscle and replacement by connective tissue with or
+without hypertrophy of the intima. In the arterioles three kinds of
+changes occur: a muscular hypertrophy; a fibrosis of all the coats; or a
+marked proliferation of the intimal endothelium. The last two are
+probably the same process, the connective tissue having its origin in
+the proliferated endothelial cells. Such a deposition of layer upon
+layer of cells in an arteriole and the resulting fibrosis leads to the
+condition of disappearance of the lumen of the vessel, endarteritis
+obliterans. This obliterating endarteritis is not, of course, due alone
+to syphilis. Syphilis is only a type of poison which produces such
+changes as have been described above. It is in the organs such as the
+kidney, liver, spleen, and intestines that one sees the most perfect
+examples of this obliterating endarteritis. Endarteritis deformans is a
+term applied to the condition of the arteries as a result of irregular
+thickenings and deposits of lime salts in the walls. These changes give
+rise to marked tortuosity of the vessels.
+
+Occasionally such an obliterating process takes place in a larger
+artery. A thrombus forms and by a process of central softening, new
+channels permeate the thrombus, thus restoring to some extent the
+function of the vessel.
+
+That the same process leads at one time to thinning and at another time
+to thickening of the arterial walls has been noted above. Prof. Adami
+holds that the regular development of layer upon layer of new connective
+tissue is non-inflammatory. He calls it a "strain hypertrophy." It is
+analogous to the localized hypertrophy of bone where the muscle tendons
+are attached, as is so frequently seen in athletes. The increased
+tension on connective tissue, provided that it is not overstrained,
+leads to its overgrowth, but only when there is sufficient nourishment.
+Such conditions are adequately fulfilled in the arteries. When a local
+giving way under pressure occurs in the media, the intima is put on the
+stretch (see Fig. 8), and there results a hypertrophy of the intima
+until the volume of the new tissue and the resistance which this affords
+to the mean distending force, balances the loss sustained by the
+weakened media. When the balance is struck, the hypertrophy is arrested.
+The youngest tissue is thus found directly beneath the endothelium. Now
+should this local weakening of the media have an acute origin, instead
+of a stimulus to growth there is overstrain, and there is, in
+consequence, not hypertrophy but atrophy. The beginning process is here
+a mesaortitis, but the acuteness of the poison, and the pressure from
+within the artery so stretches the artery that there is no compensatory
+hypertrophy, but a thinning, and the ground is prepared for aneurysmal
+dilatation or pouching.
+
+[Illustration: Fig. 8.--I, media weakened at M' with overgrowth of
+intima filling in the depression. II, with postmortem rigor and
+contraction of the muscles of the media and removal of the blood
+pressure from within, the stretched media at M'' contracts; the intimal
+thickening thus projects into the arterial lumen. (After Adami.)]
+
+Again, one not infrequently encounters intimal nodosities when the
+underlying media appears of normal thickness. The explanation of this
+apparent exception is that the media in the living aorta is actually
+thinned, but the layers of subintimal tissue deposited over the weak
+spot due to strain hypertrophy become bulged inward when the pressure is
+relieved, as at postmortem. The media has not lost all of its elasticity
+(see Fig. 9), hence it contracts and there is the appearance of a nodule
+on the intima beneath which is a media equal in thickness to that of the
+healthy surrounding media.
+
+[Illustration: Fig. 9.--Schematic representation of the increased strain
+brought to bear upon the cells of the intima, Int., when the media,
+Med., undergoes a localized expansion through relative weakness. (After
+Adami.)]
+
+The essential lesion in arteriosclerosis of the aorta and large arteries
+is a degeneration in the middle coat. This may be brought about by a
+variety of poisons circulating in the body. In syphilis, for example,
+the initial lesion has been shown to be a mesaortitis. The media seems
+to be dissolved, the artery is consequently thinned, there is actual
+depression along the level of the vessel. The elastic fibers disappear
+and small-celled infiltration takes its place. The intima hypertrophies,
+layer upon layer being added in an attempt to restore the strength of
+the vessel. There is also, as a rule, rather pronounced hypertrophy of
+the adventitia.
+
+
+=Experimental Arteriosclerosis=
+
+Within the past few years many workers have attempted by various means,
+to produce arterial lesions in animals, chiefly rabbits and dogs. The
+present status is somewhat chaotic, some affirming and some denying that
+arterial changes follow the various methods employed. Following the
+injection of small, repeated doses of adrenalin over a certain period of
+time, changes occur in the arteries of rabbits which are
+arteriosclerotic in type, the essential lesion being a degeneration of
+the muscular and elastic tissue of the media with the consequent
+production of aneurysm in the vessel. This is said by some to be quite
+like the type of arteriosclerosis in man which has been so well
+described by Moenckeberg. The degenerations in the arteries following
+the experimental lesions are of the nature of a fatty metamorphosis, and
+later proceed to calcification. Barium chloride, digitalin,
+physostigmin, nicotin and other substances, as well as adrenalin, have
+been found to exert a selective toxic action on the muscle cells of the
+middle coat of the aorta. The infundibular portion of the pituitary
+body, the portion which is developed from the infundibulum of the brain,
+possesses an internal secretion, which, injected intravenously, causes a
+marked rise of blood pressure and slowing of the heart beat. So far as I
+know, this active principle of the gland has not been used in an attempt
+to produce experimentally the lesions of arteriosclerosis.
+
+Wacker and Hueck succeeded in producing aortic disease in rabbits which
+they considered to be in many points quite like human arteriosclerosis.
+They injected the rabbits intravenously with cholesterin. They feel that
+this is of great importance in view of the fact that exercise (muscle
+metabolism) dyspnea, certain poisons, as well as adrenalin, and even
+adrenal extirpation occasion a high cholesterin content of the blood.
+Anitschow's experiments are confirmatory. He fed rabbits on large
+amounts of cholesterin-containing substances (yolk of egg, brain
+tissue) and pure cholesterin and found changes in the intima and inner
+portion of the media consisting of fatty infiltration between the muscle
+and elastic fibres, advent of small round cells and large phagocytic
+cells containing fat droplets of cholesterin esters. The elastic fibres
+were dissolved, broken up into fibrillae and these seemed to be absorbed.
+The internal elastic lamina as such disappeared and the inner layer of
+the aorta fused with the middle coat. He considers these changes to be
+quite analogous to those found in human aortas.
+
+Oswald Loeb produced changes in the arteries of rabbits by feeding them
+sodium lactate (lactic acid). His controls fed on other acids became
+cachectic, but showed no arterial changes. He further found that in 100
+gm. of human blood there was normally from 15 to 30 mg. of lactic acid.
+After heavy work, he found as much as 150 gm. He considers that after
+adrenalin or nicotin injections, the function of the liver is so
+disturbed that lactic acid is not bound. The arteriosclerosis is
+actually due to the presence of free lactic acid in the circulation. He
+succeeded, also, in producing lesions of the intima in a dog fed for a
+long time on protein poor diet, plus lactic acid and sodium lactate.
+
+Another investigator, Steinbiss, fed rabbits on animal proteins only, a
+diet totally foreign to their natural habits. He succeeded, however, in
+keeping some alive for three months. He also tried various substances
+and in the general conclusions says that no aortic changes could be
+produced in animals kept in natural living conditions by any mechanical
+means, increase of blood pressure, digital compression, hanging by hind
+legs, etc. In infectious diseases, especially septic, widespread
+sclerotic changes occurred in the aorta. A most suggestive conclusion in
+this "the most important result of feeding rabbits with animal proteins
+is, along with a constant glycosuria, disease of the aorta and
+peripheral arteries which is identical with changes in the aorta
+produced by injections of adrenalin. The degree of disease of the
+circulatory system increases with the duration of the experiment."
+
+By a small addition of vegetable to the protein diet, the lives of the
+animals were prolonged at will. With this modification of the
+experiment, the findings in the vessel walls were noticeably altered.
+The changes affected chiefly the intima, to less degree the media, and
+histologically were very much like human intimal disease.
+
+I have been unable to produce the slightest arterial lesions in rabbits
+by intravenous injections of lead. Frothingham had no success feeding
+animals with lead. In a study of autopsy material from persons up to 40
+years, who died of infectious disease, he found changes in the arteries
+of those who had succumbed to infection with the pus cocci or to very
+severe infectious disease. These changes were, however, localized, and
+were not like those of the general diffuse arteriosclerosis.
+
+Adler has recently reported experiments on dogs, to which he fed or
+injected intravenously various substances supposed to induce
+arteriosclerotic changes. He was unable to find any arterial lesions
+comparable to human arteriosclerosis.
+
+The difficulty experienced by experimenters is not surprising when the
+character of the changes is considered. Arteriosclerosis is not an acute
+process. In its very nature, it is of months' or years' standing, the
+specific changes are of slow growth, and more in the nature of
+degeneration. It would seem that a very careful study of the histories
+of those with arteriosclerosis and a final examination upon the actual
+tissue might eventually give us data for the etiology.
+
+The most frequent site of disease in these experimental lesions is the
+thoracic aorta, and it is there also that the most severe changes are
+seen. While the toxic action is felt in the vessels all over the body,
+the lesions are, as a rule, scattered and small. The thoracic aorta
+stands the brunt of the high pressure, and this combined with the
+poisonous action of the drug or drugs, results in the formation of a
+fusiform aneurysmal dilatation which stops at the diaphragmatic opening.
+The aortic opening in the diaphragm seems to act as a flood gate,
+allowing only a certain amount of blood to flow through, and thus the
+abdominal aorta is protected to a great extent from the deleterious
+effects of increased pressure. Focal degenerative lesions are, however,
+found in the abdominal aorta.
+
+Changes somewhat analogous to those found in the human aorta as the
+result of intimal proliferations, are produced in animals by the toxins
+of the typhoid bacillus and the Streptococcus pyogenes. Clinically,
+Thayer and Brush have found that the arteries of those who have
+recovered from an attack of typhoid fever are more palpable than the
+arteries of average individuals of equal age who have never had the
+disease.
+
+Experimentally, the changes caused by the toxins above noted are
+proliferations of cells in the intima and subintimal tissues, and a
+breaking up of the internal elastic laminae into several parallel layers
+which stretch themselves among the proliferating cells. The diphtheria
+toxin, on the contrary, produces a lesion more like that caused by
+adrenalin. All pathologists are not agreed as to whether the
+experimental lesions produced by blood pressure raising drugs are
+similar to the arteriosclerotic changes in the arteries of man.
+
+Some of the work on rabbits has been discredited for the reason that
+arteriosclerosis appears spontaneously in about fifteen per cent of all
+laboratory rabbits. Furthermore, comparatively young rabbits have been
+found with arteriosclerosis. O. Loeb, however, denies this. He has
+examined in the course of eight years 483 healthy rabbits and never
+found arterial changes. The spontaneous lesions can not be distinguished
+histologically from those due to adrenalin. They differ macroscopically
+in that the lesion is usually limited to a few foci near the origin of
+the aorta.
+
+Lesions produced by the drugs enumerated above represent one type of
+experimental arteriosclerosis. More interesting and important are the
+experiments which seem to show that high tension alone is capable of
+producing lesions in arteries which in all respects correspond to
+Adami's strain hypertrophy and overstrain theory. It has been shown that
+when a portion of vein is placed under conditions of high arterial
+pressure, as in a transplantation of a portion of vein into a carotid
+artery, the vein undergoes marked connective tissue hypertrophy which
+includes all the coats. This is evidently strain hypertrophy. Again, it
+has been demonstrated that by suspending a previously healthy rabbit by
+the hind legs for three minutes daily over a period of three to four
+months, there results hypertrophy of the heart with thinning and
+dilatation of the arch and the upper part of the thoracic aorta. No
+change was found in the abdominal aorta. The carotids, however, were
+larger than normal and they showed typical intimal sclerosis with
+connective tissue thickening.
+
+Neither I nor others have been able to confirm this experiment, so it is
+very doubtful whether mechanical pressure alone can produce true
+arteriosclerosis. Some evidence is adduced to bear on this point,
+however, in the fact that sclerosis of the pulmonary artery follows
+often upon mitral stenosis. Yet we do not know but that factors other
+than pressure alone produce the arteriosclerotic change in such cases,
+so we are forced back on our conclusion expressed above; viz., that
+experiments on animals fail to sustain the purely mechanical origin of
+arteriosclerosis.
+
+The changes in the intima constitute the effort on the part of nature to
+repair a defect in the vessel wall which is to compensate for the
+weakened media and the widened lumen. This applies only to true
+arteriosclerosis, not to the condition produced experimentally by the
+toxin of the typhoid bacillus, for example.
+
+When an artery loses its elasticity and begins to have connective tissue
+deposited in its walls, the pressure of the blood stretches the vessel
+which is now no longer capable of retracting when the pulse wave has
+passed, and, in consequence, the artery is actually lengthened. This
+necessarily causes a tortuosity of the vessel which can be easily seen
+in such arteries as the temporals, brachials, radials, and other
+arteries near the surface of the skin.
+
+The exact mechanism of increase of blood pressure is not satisfactorily
+explained. The smaller arteries all over the body are supplied with
+vasoconstrictor and vasodilator nerve fibers from the sympathetic
+nervous system. Normally when an organ is actively functionating the
+vessels are widely dilated and the flow of blood is rapid. Among the
+many factors which influence blood pressure and blood supply must be
+reckoned the psychic.
+
+We know that normally there is a certain resistance offered to the
+propulsion of blood through the arteries by the contraction of the
+heart. This tonus is essential to the maintenance of an equalized
+circulation. The muscular arterioles throughout the body by their tonus
+serve to keep up the normal blood pressure and to distribute the blood
+evenly to the various organs. Contraction of a large area of arterioles
+increases the blood pressure and, strangely enough, the arteries respond
+to increased arterial pressure, not by dilatation, but by contraction.
+It would appear that rise of blood pressure tends to throw increased
+work upon the musculature of the arterioles. This may be sufficient only
+to cause them to hypertrophy, but further strain may easily lead to
+exhaustion and to dilatation. "As a result strain hypertrophy of the
+intima shows itself with thickening, and it may also be of the
+adventitia, resulting in chronic periarteritis. And now with continued
+degeneration of the medial muscle in those muscular arteries, fibrosis
+of the media may also show itself. I would thus regard muscular
+hypertrophy of the arteries and fibrosis of the different coats as
+different stages in one and the same process. Whether these peripheral
+changes are the more marked, or the central, depends upon the relative
+resisting power of the elastic and muscular arteries of the individual
+respectively." (Adami.)
+
+[Illustration: Fig. 10.--Cross-section of a small artery in the
+mesentery. Note that the vessel appears capable of being much widened.
+The internal elastic lamina is thrown into folds somewhat resembling the
+convolutions of the brain. Note also that the middle coat of the artery
+is composed almost entirely of muscle. The enormous number of such
+vessels in the mesentery and intestines explains the ability of the
+splanchnic area to accommodate the greater part of the blood in the
+body. Universal constriction of these vessels would naturally render the
+intestines anemic. The vasomotor control of these vessels plays an
+important role in the distribution of the blood. Small arteries in the
+skin and in other organs, possibly the brain, have a similar function.
+(Microphotograph, highly magnified.)]
+
+It is conceivable that in one section of the body the vessels may be
+markedly contracted, but if there is dilatation in some other part there
+will be no increased work on the part of the heart, and theoretically,
+there should be no rise of blood pressure. The vascular system, however,
+while likened to a system of rubber tubes, must be regarded as a very
+live system, every subsystem having the property of separate control.
+
+For blood tension to be raised all over the body, conditions must favor
+the generalized contraction of a large area of arterioles. Some authors
+consider that the so-called viscosity of the blood also is a factor in
+the causation of increased tension. The usual cause for the high tension
+is probably the presence in the blood of some poisonous substance.
+
+It is held by some authors that the great splanchnic area is capable of
+holding all the blood in the body and in respect of its liability to
+arteriosclerosis, it is second only to the aorta and coronary arteries.
+The enormous area of the skin vessels could probably contain most of the
+blood. The tone of the vasoconstrictor center controls the distribution
+of blood throughout the body. The fact that the vessels in the
+splanchnic area are frequently attacked by sclerotic changes means, as a
+rule, increase of work for the heart.[1] The resistance offered to the
+passage of the blood must be great and signifies that, for blood to
+travel at the same rate that it did before the resistance set in, more
+power must be expended in its propulsion. In other words, the heart must
+gradually become accustomed to the changed conditions, and, as a result
+of increased work, the muscle hypertrophies. (See Fig. 11.)
+
+ [1] Longcope and McClintock, however, conclude that permanent
+ constriction of the superior mesenteric artery and celiac axis, as well
+ as gradual occlusion of one or both of these vessels, may be present in
+ dogs for at least five months without giving rise to definite and
+ constant elevation of blood pressure or to hypertrophy of the heart.
+ Further, they have been unable to find at autopsy on man a definite
+ association between sclerosis of the abdominal aorta and great
+ splanchnic vessels and cardiac hypertrophy.
+
+[Illustration: Fig. 11.--Enormous hypertrophy of left ventricle probably
+due to prolonged increased peripheral resistance. Note that the whole
+anterior surface of the heart is occupied by the left ventricle. The
+right ventricle does not appear to be much affected. x2/3.]
+
+In diffuse arteriosclerosis accompanied by chronic nephritis the heart
+is always hypertrophied. This is a result, not a cause of the
+condition. In the pure type, there is hypertrophy only of the left
+ventricle without dilatation of the chamber. The muscle fibers are
+increased in number and in size, and there are frequently areas of
+fibrous myocarditis due to necrosis caused by insufficient nutrition of
+parts of the muscle. In these cases the coronary arteries share in the
+generalized arteriosclerotic process. The openings of the arteries
+behind the semilunar valves may be very small. There is often thickening
+and puckering of the aortic valves and of the anterior leaflet of the
+mitral valve leading, at times, to actual insufficiency of the orifice.
+Later, when the heart begins to weaken, there is dilatation of the
+chambers and loud murmurs result, caused by the inability of the
+nondistensible valves to close the dilated orifices. Until the
+compensation is established, it is impossible to say whether or not true
+insufficiency is present.
+
+In senile arteriosclerosis there is the physiologic atrophy of the media
+to be reckoned with. This change has already been referred to. When such
+degeneration has taken place, the normal blood pressure may be
+sufficient to cause stretching of the already weakened media with or
+without hypertrophy of the intima. The arteries may be so lined with
+deposits of calcareous matter that they appear as pipe stems. More
+frequently there are rings of calcified material placed closely together
+or irregular beading, giving to the palpating finger the impression of
+feeling a string of very fine beads. The arteries are often tortuous,
+hard, and are absolutely nondistensible. At times no pulse wave can be
+felt.
+
+The larger arteries such as the brachials and femorals are most
+affected. The walls become thinned and show cracks, and areas
+apparently, but not actually denuded of intima. Yellowish-white,
+irregular, raised plaques are scattered here and there. Interspersed
+among these areas are irregularly shaped clean-cut ulcers having as a
+rule a smooth base, and frequently on the base is a thin plate of
+calcified matter. The color of these denuded areas is usually brownish
+red or reddish brown. White thrombi may be deposited on these areas. The
+danger of an embolus plugging one of the smaller arteries is great and
+probably happens more often than we think. The collateral circulation is
+able to supply the thrombosed area. Should the thrombus be on the
+carotid arteries, hemiplegia may result from cerebral embolism. On
+microscopic examination of the arteries there is seen extreme
+degeneration of all the coats, the degeneration of the media leading
+almost to an obliteration of that coat. On seeing such arteries as these
+one wonders how the circulation could have been maintained and the
+organs nourished. Senile atrophy of the internal organs naturally goes
+hand in hand with such arterial changes.
+
+There is, as a rule, no increase in arterial tension; on the contrary,
+the pressure is apt to be low. This is readily understood when the heart
+is seen. This organ is small, the muscle is much thinned, it is flabby
+and of a brownish tint, the so-called "brown atrophy." Microscopically,
+there is seen to be much fragmentation of the fibers with a marked
+increase of the brown pigment granules which surround the cell nuclei.
+Cases are seen, however, in which blood pressure increases as the
+patient grows older. The hearts in such cases are more or less
+hypertrophied and show extensive areas of fibroid myocarditis.
+
+From what has been said, it follows that hypertension alone may be the
+cause of arteriosclerosis; that certain poisons in the blood which
+attack the media and cause it to degenerate and weaken cause
+arteriosclerosis without increased blood pressure; that the normal blood
+pressure may be, for the artery which is physiologically weakened in an
+individual over fifty, really hypertension, and arteriosclerosis may
+result. Our observations lead us to believe that the process is at
+bottom one and the same. The different types noted clinically depend
+upon the nature of the etiologic factors and the kind of arterial tissue
+with which the individual is endowed. This view at least brings some
+order out of previous chaos, and corresponds well with our present
+knowledge of the disease.
+
+There are many cases of arteriosclerosis which lead to definite
+interference with the closure of the valves of the heart, particularly
+the aortic and the mitral. It has been said that puckerings of the
+valves frequently occur (Fig. 12). This arteriosclerotic endocarditis at
+times leads to very definite heart lesions, chiefly aortic or mitral
+insufficiency, or both with, at times, murmurs of a stenotic character
+at the base. There is rarely true aortic stenosis, however. The murmur
+is caused by the passage of the blood over the roughened valves and into
+the dilated aorta. Aortic stenosis is one of the rarest of the valvular
+lesions affecting the valves of the left heart, and should be diagnosed
+only when all factors, including the typical pulse tracings, are taken
+into consideration.
+
+[Illustration: Fig. 12.--Aortic incompetence with hypertrophy and
+dilatation of left ventricle, the result of arteriosclerosis affecting
+the aortic valves. Note how the valves have been curled, thickened, and
+shortened, the edges of valves being a half inch below the upper points
+of attachment. The anterior coronary artery is shown, the lumen
+narrowed. (Reduced one-half.)]
+
+The kidneys, as a rule, show extensive sclerosis. They are small, firm,
+and contracted and not always to be differentiated from the contracted
+kidneys of chronic inflammation. The lesions of the arteriosclerotic
+kidney are due to narrowing and eventual obstruction of the afferent
+vessels. The organs are usually bright red or grayish red in color. At
+times there is marked fatty degeneration of cortex and medulla, giving
+to them a yellowish streaking. The capsule is here and there adherent,
+the cortex is much thinned and irregular. The surface presents a
+roughly granular appearance. The glomeruli stand out as whitish dots
+and the sclerosed arteries are easily recognized, as their walls are
+much thickened. The process does not, as a rule, affect the whole kidney
+equally, but rather affects those portions corresponding to the
+interlobular arteries. The replacement of the normal kidney tissue by
+connective tissue and the resulting contraction of this latter tissue
+leads to the formation of scars. As the process is not regular, the
+scarring is deeper in some places than in others, with the result that
+localized rather sharply depressed areas appear on the surface. The
+pelvis is relatively large and is filled with fat. The renal artery is
+often markedly sclerosed and the whole process may be due to localized
+thickening of the artery, or as part of a general arteriosclerosis. The
+latter is the more frequent. Microscopically, it is seen that the
+tubules are atrophied, the Bowman's capsules are, as a rule, thickened,
+and the glomeruli are shrunken or have been replaced by fibrous tissue.
+In places they have fallen out of the section. There is marked
+proliferation of connective tissue in cortex and medulla. The arterioles
+are thickened, the sclerosis being either of the intima or media or of
+both. There is even occlusion of many arterioles.
+
+Changes in other organs as the result of arteriosclerosis of their
+afferent vessels occur, but are not so characteristic as in the kidney.
+In the brain the result of gradual thickening of the arterioles is a
+diminished blood supply, softening of the portion supplied by the
+artery, and later a connective tissue deposit. The occurrence of thrombi
+is favored and, now and again, a thrombus plugs an artery which supplies
+an important and even vital part of the brain. The arteries of the brain
+are end arteries, hence there is no chance for collateral circulation.
+It is therefore evident how serious a result may follow the disturbance
+in or actual deprivation of blood supply to any of the brain centers or
+to the internal capsule.
+
+
+=Arteriosclerosis of the Pulmonary Arteries=
+
+There have been a number of cases of sclerosis of the pulmonary
+arteries, either alone, or associated with general systemic
+arteriosclerosis.
+
+A primary and a secondary form are recognized, the former in conjunction
+with congenital malformations of the heart, the latter as the result of
+severe infection or of mitral stenosis. These two causes seem to be the
+most important in the production of the arterial changes. The cases thus
+far described have revealed widespread thickening of the pulmonary
+arteries. If one may judge by the description of the pathologic changes,
+the condition is quite similar to that produced in a vein by
+transplantation along the course of an artery. The diffuse form with
+connective tissue thickening of all coats has been generally described.
+There is also obliterating endarteritis of the smaller vessels. In the
+etiology of the condition severe infection seems to play a prominent
+role. The constant presence of right ventricular hypertrophy is
+interesting, the heart dullness extends, as a rule, far to the right of
+the sternum. In some of the cases no demonstrable changes were observed
+in the bronchial arteries or in the pulmonary veins.
+
+Sanders has described a case of primary pulmonary arteriosclerosis with
+hypertrophy of the right ventricle.
+
+Recently Warthin[2] has reported a case of syphilitic sclerosis of the
+pulmonary artery which places the lesion in exactly the same category as
+that of syphilis in the systemic arteries. There was also aneurysm of
+the left upper division present and, to settle the etiologic nature of
+the process, Spirochete pallida were found in the wall of the aneurysm
+sac and in that of the pulmonary artery. The microscopic picture in the
+pulmonary artery could not be told from that in a syphilitic aorta.
+
+ [2] Warthin, A. S.: Am. Jour. Syph., 1918, i, 693.
+
+
+=Sclerosis of the Veins=
+
+Phlebosclerosis not infrequently occurs with arteriosclerosis. It is
+seen in those cases characterized by high blood pressure. Such increased
+pressure in the veins is due, for example, to cirrhosis of the liver
+which affects the portal circulation, or to mitral stenosis which
+affects the pulmonary veins. The affected vessels are usually dilated.
+The intima shows compensatory thickening especially where the media is
+thinned. As a rule all the coats are involved in the connective tissue
+thickening. Occasionally hyaline degeneration or calcification of the
+new-formed tissue is seen. "Without existing arteriosclerosis the
+peripheral veins may be sclerotic usually in conditions of debility, but
+not infrequently in young persons." (Osler.)
+
+In many cases of arteriosclerosis, the pathologic changes are not
+confined to the arteries, but are found in the veins as well as in the
+capillaries. Such cases could be called angiosclerosis.
+
+
+
+
+CHAPTER III
+
+PHYSIOLOGY OF THE CIRCULATION
+
+
+No attempt will be made to cover the entire subject of the physiology of
+the circulation. Only in so far as it relates to arteriosclerosis and
+blood pressure and has a bearing on the probable explanation of blood
+pressure phenomena will it be discussed.
+
+"The heart and the blood vessels form a closed vascular system,
+containing a certain amount of blood. This blood is kept in endless
+circulation mainly by the force of the muscular contractions of the
+heart; but the bed through which it flows varies greatly in width at
+different parts of the circuit, and the resistance offered to the moving
+blood is very much greater in the capillaries than in the large vessels.
+It follows, from the irregularities in size of the channels through
+which it flows, that the blood stream is not uniform in character
+throughout the entire circuit--indeed, just the opposite is true. From
+point to point in the branching system of vessels the blood varies in
+regard to its velocity, its head of pressure, etc. These variations are
+connected in part with the fixed structure of the system and in part are
+dependent upon the changing properties of the living matter of which the
+system is composed." (W. H. Howell.)
+
+If the vascular system were composed of a central pump, projecting at
+every stroke a given amount of liquid into a series of rigid tubes, the
+aggregate cross sections of which were equal to the cross section of the
+main pipe, then the velocity at the openings would be the same as at the
+source (making allowances for friction). The problem would then be a
+simple one. In the circulation of the blood no such simple condition
+obtains. The capillary beds is an enormous area through which the blood
+flows slowly. From the time the blood is thrown into the aorta the
+velocity begins to diminish until it reaches its minimum in the
+capillaries. In no two persons is the initial velocity at the heart the
+same, nor in the same person is it the same at all times of day. The
+size of the heart, the actual strength of the muscle, the amount of
+blood ejected at every beat, and the size and elasticity of the aorta
+are some of the factors which determine the velocity of blood at the
+aortic orifice. When to these factors are added the differences in
+arterial tissue, the activity or resting stage of the various organs,
+etc., the question becomes exceedingly complicated. In spite of these
+many disturbing elements, attempts more or less successful have been
+made to estimate the velocity of the blood in animals. Thus, in the
+carotid of the horse the velocity was found to be 300 mm. per second
+(Volkman) and 297 mm. (Chauveau); in the carotid of the dog, 260 mm.
+(Vierordt). In the jugular vein of the dog Vierordt found the velocity
+to be 225 mm. per second. These figures do not represent the actual
+velocity of the blood in all horses or all dogs, but they do give us
+some general idea of the rate of flow of the blood. For man it has been
+calculated that the velocity in the aorta is about 320 mm. per second.
+The velocity is not uniform in the large arteries, where at every heart
+beat there is a sudden increase followed by a decrease as the heart goes
+into diastole. The farther away from the heart the measurements are made
+the more even is the flow.
+
+Observations by W. H. Luedde with the Zeiss binocular corneal microscope
+on the rate of flow in the conjunctival capillaries must modify somewhat
+our former conceptions. He finds that "The rate varies in the different
+arteries, capillaries, and veins from a barely perceptible motion to a
+little more than 1 mm. per second. Further, some parts of the capillary
+network are ordinarily supplied with blood elements only occasionally.
+This is shown by the passage of a column of corpuscles along a certain
+line, followed after an interval of seconds, during which no corpuscles
+pass, by another column in the same line as before."
+
+The vessels of the conjunctiva probably are quite like superficial
+vessels in the skin and mucous membranes. Therefore, we must be free to
+admit that the circulation in them is not absolutely steady. Luedde
+found further that in syphilitics there were tortuosities,
+irregularities, minute aneurysmal dilatations and even obliterations of
+capillaries. Some of the changes occurred as early as one month after
+infection.
+
+The rate in the capillaries of man is estimated to be between 0.5 mm.
+and 0.9 mm. per second. As the blood is collected into the veins and the
+bed becomes smaller, the velocity increases until at the heart it is
+almost the same as in the aorta. That the velocity could not be exactly
+the same is evident from the fact that the cross section of the veins,
+which return the blood to the right auricle, is greater than is the
+cross section of the aorta.
+
+The volume of the bed is subject to rapid and wide fluctuations, which
+are dependent on many causes, both physiologic and pathologic. The call
+of an actively functionating organ or group of organs causes a widening
+of a more or less extensive area, and the velocity necessarily varies.
+In states of great relaxation of the vessels there may be a capillary
+pulse. In order to force blood at the same rate through dilated vessels
+as through normal vessels, there must be more blood or there must be a
+more rapid contraction of the central pump. What actually happens, as a
+rule, is an increase in the rate of the heart beat. There are
+conditions--such, for example, as aortic insufficiency--where actually
+more blood is thrown into the circulation at every beat, so that the
+rate is not changed.
+
+It has been calculated that the average amount of blood thrown into the
+aorta at every systole of the heart is from 50 to 100 c.c. This is
+forcibly ejected into a vessel already filled (apparently) with blood.
+In order to accommodate this sudden accession of fluid, the aorta must
+expand. The aortic valves close, and during diastole the blood is forced
+through the vascular system by the forcible, steady contraction of the
+highly elastic aorta. Other large vessels which branch from the aorta
+also have a part in this steady propulsion of blood. From seventy to
+eighty times a minute the aorta is normally forcibly expanded to
+accommodate the charge of the ventricle. It is not difficult to
+understand the great frequency of patches of sclerosis in the arch when
+these facts are borne in mind.
+
+What relationship the viscosity of the blood has to the rate and volume
+of flow is not fully understood. As yet there is not much known about
+the subject, and no one has devised a satisfactory means of measuring
+the viscosity. It is thought by some that an increased viscosity assists
+in producing an increased amount of work for the heart.
+
+
+=Blood Pressure=
+
+Blood pressure is the expression used for a series of phenomena
+resulting from the action of the heart. As every heart beat is actual
+work done by the heart in overcoming resistance to the outflow of blood,
+this force is approximately measurable in a large artery such as the
+brachial. It has been determined that the pressure in the brachial
+artery is almost equal to the intraventricular pressure in the left
+ventricle. In animals it is easy to attach manometers to the carotid
+artery and to measure the blood pressure accurately. Formerly the method
+consisted in attaching a tube and allowing the blood to rise in the
+tube. The height to which the blood rose measured the maximum pressure.
+This is a crude method and has been replaced by the U-tube of mercury
+with connection made to the artery by saline or Ringer's solution. This
+apparatus is familiar to all physiologists.
+
+In man the measurement is most conveniently made from the brachial
+artery. There is some difference in the pressure in the femoral and the
+brachial and some use both arteries. However, the difficulty of
+adjusting instruments to the upper leg, the great force which must be
+used to compress the femoral artery and the relative inaccessibility of
+the leg as compared to the arm, make the leg an inconvenient part for
+use in blood pressure determinations. It is not to be recommended.
+
+Blood pressure is a valuable aid in diagnosis and of material help in
+many cases in prognosis, but it is not infallible neither can it be used
+alone to diagnose a case. Blood pressure is only one of many links in a
+chain of evidence leading to diagnosis. It has been badly used and much
+abused. It has been condemned unjustly when it did not furnish _all_ the
+evidence. It has been made a fetish and worshipped by both doctors and
+patients. A sane conception of blood pressure must be widely
+disseminated lest we find it being discarded altogether.
+
+Blood pressure consists of more than the estimation of the systolic
+pressure. The blood pressure picture consists of (1) the systolic
+pressure, (2) the diastolic pressure, (3) the pulse pressure which is
+the difference between the systolic and diastolic pressure, (4) the
+pulse rate. Expressed in the literature it should read thus: 120-80-40;
+72. That tells the whole story in a brief, accurate form. This is
+recommended in history reporting. It must be ever kept in mind that a
+blood pressure reading represents the work of the heart at the _moment
+when it was taken_. Within a few minutes the pressure may vary up or
+down. There is no normal pressure as such, but an average pressure for
+any group of people of the same age living under similar conditions. The
+habit of speaking of any systolic figure as normal should be broken. A
+pressure picture may be normal but a systolic reading, whatever it may
+be, is not accurately designated as normal. This distinction is worth
+insisting upon.
+
+
+=Blood Pressure Instruments=
+
+There are several instruments which are in common use for the purpose of
+recording blood pressure in man.
+
+Historically, the determination of blood pressure for man began with the
+attempt of K. Vierordt in 1855 to measure the blood pressure by placing
+weights on the radial pulse until this was obliterated. The first useful
+instrument, however, was devised by Marcy in 1876. He placed the hand in
+a closed vessel containing water connected by tubing with a bottle for
+raising the pressure and by another tube with a tambour and lever for
+recording the size of the pulse waves. He maintained that when pressure
+on the hand was made, the point where oscillations of the lever ceased
+was the maximal pressure, the point where the oscillations of the
+recording lever was largest, was the minimal pressure.
+
+This pioneer work was practically forgotten for twenty-five years. It
+was not until 1887 that V. Basch devised an instrument which was used to
+some extent. This instrument recorded only maximum pressure. It
+consisted of a small rubber bulb filled with water communicating with a
+mercury manometer. The bulb was pressed on the radial artery until the
+pulse below it was obliterated and the pressure then read off on the
+column of mercury. V. Basch later substituted a spring manometer for the
+mercury column. Potain modified the apparatus by using air in the bulb
+with an aneroid barometer for recording the pressure. These instruments
+are necessarily grossly inaccurate. Moreover, they do not record the
+diastolic pressure.
+
+In 1896 and 1897 further attempts were made to record blood pressure by
+the introduction of a flat rubber bag encased in some nonyielding
+material, which was placed around the upper arm. Riva-Rocci used silk,
+while Hill and Barnard used leather. The latter used a bulb or Davidson
+syringe to force air into the cuff around the arm and palpated the
+radial artery at the wrist, noting the point of return of the pulse
+after compression of the upper arm, and reading the pressure on a column
+of mercury in a tube.
+
+Except that the width of the cuff has been increased from 5 cm. to 12
+cm., this is the general principle upon which all the blood pressure
+instruments now in use are based. Most of the apparatuses make use of a
+column of mercury in a U-tube to record the millimeters of pressure. As
+the mercury is depressed in one arm to the same extent as it is raised
+in the other arm the scale where readings are made is .5 cm. and the
+divisions represent 2 mm. of mercury but are actually 1 mm. apart.
+
+The cuff was made 12 cm. in diameter because it was shown (v.
+Recklinghausen) that with narrow cuffs much pressure was dissipated in
+squeezing the tissues. Janeway has shown that with the use of the 12 cm.
+cuff accurate values are obtained independently of the amount of muscle
+and fat around the brachial artery. In other words if an actual systolic
+blood pressure of 140 mm. is present in two individuals, the one with a
+thin arm, the other with a thick arm, the instrument will record these
+pressures the same where a 12 cm. arm band is used. We need have no fear
+of obtaining too high a reading when we are taking pressure in a stout
+or very muscular individual. Janeway also was the first to call
+attention to the fact that the diastolic or minimal pressure was at the
+point where the greatest oscillation of the mercury took place. This is
+difficult to estimate in many cases as the eye can not follow slight
+changes in the oscillation when the pressure in the cuff is gradually
+reduced. Practically this is the case in small pulses.
+
+The Riva-Rocci instrument was modified by Cook. (See Fig. 13.) He used a
+glass bulb containing mercury into which a glass tube projected. The
+bulb was connected by outlet and tubing to the cuff and syringe. The
+glass tube was marked off in centimeters and millimeters and for
+convenience was jointed half way in its length. The instrument could be
+carried in a box of convenient size. This instrument is fragile and more
+cumbersome, although lighter in weight, than others and is very little
+used at present.
+
+[Illustration: Fig. 13.--Cook's modification of Riva-Rocci's blood
+pressure instrument.]
+
+Stanton's instrument (Fig. 14) is practically Cook's made more rigid in
+every way but without the jointed tube. The cuff has a leather casing,
+the pressure bulb is of heavy rubber, the glass tube in which the
+mercury rises is fixed against a piece of flat metal and there are
+stopcocks in a metal chamber introduced between the bulb and mercury
+with which to regulate the in- and out-flow of air. The pressure can be
+gradually lowered conveniently without removing the pressure bulb.
+
+[Illustration: Fig. 14.--Stanton's sphygmomanometer.]
+
+The most accurate mercury manometer is that of Erlanger. (Fig. 15.) The
+instrument is bulky and is not practicable for the physician in
+practice. The principle is that used by Riva-Rocci. There is an extra
+T-tube introduced between the manometer and air bulb connecting with a
+rubber bulb in a glass chamber. The oscillations of this are
+communicated to a Marey tambour and recorded on smoked paper revolving
+on a drum. There is a complicated valve which enables the operator to
+reduce the pressure with varying degrees of slowness. The mercury is
+placed in a U-tube with a scale alongside it. The instrument is
+expensive and not as easy to manipulate as its advocates would have us
+believe. Hirschfelder has added to the usefulness (as well as to the
+complexity) of the Erlanger instrument, by placing two recording
+tambours for the simultaneous registering of the carotid and venous
+pulses. In spite of its complexity and necessary bulkiness, very
+valuable data are obtained concerning the auricular contractions.
+
+[Illustration: Fig. 15.--The Erlanger sphygmomanometer with the
+Hirschfelder attachments by means of which simultaneous tracings can be
+obtained from the brachial, carotid, and venous pulses.]
+
+One of the best of the mercury instruments is the Brown
+sphygmomanometer. In this (Fig. 16) the mercury is in a closed,
+all-glass tube so that it can not spill under any sort of manipulation.
+It is in this sense "fool-proof." The cuff, however, is poorly
+constructed. It is too short and there are strings to tie it around the
+arm. I have found that this causes undue pressure in a narrow circle and
+renders the reading inaccurate. In the clinic we use this mercury
+instrument with a long cuff like that provided by the Tycos instrument.
+
+[Illustration: Fig. 16.--Desk model Baumanometer.]
+
+The Faught instrument (Fig. 17) is larger than the Brown, but is less
+easily broken and is not too cumbersome to carry around. The
+substitution of a metal air pump for the rubber makes the apparatus more
+durable.
+
+[Illustration: Fig. 17.--The Faught blood pressure instrument. An
+excellent instrument which is quite easily carried about and is not
+easily broken.]
+
+The v. Recklinghausen instrument is not employed to any extent in this
+country. It is both expensive and cumbersome, and has no advantages over
+the other instruments.
+
+Several other instruments have been devised and new ones are constantly
+being added to the already large list. With those employing mercury the
+principle is the same. The aim is to make an instrument which is easily
+carried, durable, and accurate.
+
+In all the mercury instruments the diameter of the tube is 2 mm. One
+would suppose that there would be noticeable differences in the readings
+of the different mercury instruments depending upon the amount of
+mercury used in the tube. By actual weight there is from 35 to 45 gms.
+of mercury in the several instruments. After many trials, no noticeable
+differences in blood pressure readings can be made out between a column
+weighing 35 gm. and one weighing 45 gm.
+
+There is, however, the inertia of the mercury to be overcome, friction
+between the tube and the mercury, and vapor tension. The mercury is
+therefore not as sensitive to rapid changes of pressure in the cuff as a
+lighter fluid would be. The mercury must be clean and the tube dry so
+that there is no more friction than what is inherent between the mercury
+and glass. In making readings on a rapid pulse the oscillations of the
+mercury column are apt to be irregular or to cease now and then, due to
+the fact that the downward oscillation coincides with a pulse wave, or
+an upward oscillation receives the impact of two pulse waves transmitted
+through the cuff. Instruments have been devised to obviate this
+difficulty, but they have not come into favor. They are usually too
+complicated and at present can not be recommended.
+
+[Illustration: Fig. 18.--Rogers' "Tycos" dial sphygmomanometer.]
+
+An instrument devised by Dr. Rogers (the "Tycos") has met with
+considerable popularity. (Fig. 18.) This is not an instrument which
+operates with a spring and lever. The instrument is composed essentially
+of two metal discs carefully ground and attached at their circumferences
+to the metal casing below the dial. There is an air chamber between
+these discs through the center of which air is forced by the syringe
+bulb. When air is forced into the space between these two discs, they
+are forced apart to a very slight extent, with the highest pressures
+only 2-3 mm. of bulging occurs. From data gathered after extensive use
+for five years these discs were not found to have sprung. A lever
+attached to a cog which in turn is attached to the dial needle magnifies
+to an enormous extent the slightest expansion of the discs. Every dial
+is handmade and every division is actually determined by using a U. S.
+government mercury manometer of standard type. No two dials therefore
+are alike in the spacing of the divisions of the scale but every one is
+calibrated as an individual instrument. There is no doubt in the
+author's mind that for the general practitioner the instrument has some
+advantages over the mercury instruments. It reveals the slightest
+irregularity in force of the heart beat. The oscillation of the dial
+needle is more accurately followed by the eye than is that of the column
+of mercury. The needle passes directly over the divisions of the scale,
+while with usual mercury instruments the scale is an appreciable
+distance (sometimes .5 cm.) from the column of mercury at the side.
+(Fig. 19.) The diastolic pressure is more easily read on the "Tycos."
+It is where the maximum oscillation of the needle occurs as the pressure
+is slowly released from the cuff. Although it does not appear that this
+instrument, if properly made and standardized, could become inaccurate,
+nevertheless it is advisable to check it every few months against a
+known accurate mercury manometer instrument.
+
+[Illustration: Fig. 19.--Detail of the dial in the "Tycos" instrument.]
+
+[Illustration: Fig. 20.--Faught dial instrument.]
+
+[Illustration: Fig. 21.--Detail of the dial of the Faught instrument.]
+
+Another perfectly satisfactory dial instrument is the Faught (Figs. 20
+and 21). The general plan of this differs in some minor points from the
+"Tycos." I have compared the two and have found no difference in the
+readings. Both can be recommended.
+
+[Illustration: Fig. 22.--The Sanborn instrument.]
+
+One or two other cheaper dial instruments are on the market. The Sanborn
+seems to be quite satisfactory. (Fig. 22.) It is cheaper than the other
+dial instruments. There is this much to be said, no instrument using a
+spring as resistance to measure pressure can be recommended.
+
+
+=Technic=
+
+The same technic applies to all the mercury instruments. The patient
+sits or lies down comfortably. The right or left arm is bared to the
+shoulder, the cuff is then slipped over the hand to the upper arm. (See
+Fig. 23.) At least an inch of bare arm should show between the lower end
+of the cuff and the bend of the elbow. The rubber is adjusted so that
+the actual pressure from the bag is against the inner side of the arm.
+The straps are tightened, care being taken not to compress the veins.
+The upper part of the cuff should fit more snugly than the lower part.
+The part of the instrument carrying the mercury column is now placed on
+a level surface; the two arms of the mercury in the tube must be even,
+and at _0_ on the scale. With the fingers of one hand on the radial
+pulse, the bag is compressed until the pulse is no longer felt. (See
+Fig. 24.) One should raise the pressure from 10-12 mm. above this, and
+close the stopcock between the bulb and the mercury tube. In a good
+instrument the column should not fall. If it does there is a leak of air
+in the system of tubing and arm bag. Now with the finger on the pulse,
+or where the pulse was last felt, gradually allow air to escape by
+turning the stopcock so that the column of mercury falls about 2 mm.
+(one division on the scale) for every heart beat or two. One must not
+allow the column of mercury to descend too slowly as it is
+uncomfortable for the patient and introduces a psychic element of
+annoyance which affects the blood pressure. On the other hand, the
+pressure must not be released too rapidly, else one runs over the points
+of systolic and diastolic pressure and the readings are grossly
+inaccurate. It is impossible to say how rapidly the mercury must fall.
+Every operator must find that out for himself by practice. The first
+perceptible pulse wave felt beneath the palpating finger at the wrist,
+represents on the scale the systolic pressure. This can be seen to
+correspond to a sudden increase in the magnitude of the oscillation of
+the mercury column. The systolic pressure, thus obtained, is from 5-10
+mm. lower than the real systolic pressure. The more sensitive the
+palpating finger, the more nearly does the systolic pressure reading
+approach that found by using such an instrument as Erlanger's, where the
+first pulse wave is magnified by the lever of the tambour.
+
+[Illustration: Fig. 23.--Method of taking blood pressure with a patient
+in sitting position.]
+
+[Illustration: Fig. 24.--Method of taking blood pressure with patient
+lying down.]
+
+The pressure is now allowed to fall, until the palpating finger feels
+the largest possible pulse wave, which is coincident with the greatest
+oscillation of the mercury. This is the diastolic pressure. Beyond this
+point there is no oscillation of the mercury column. The difference
+between the two is the pulse pressure. Thus the pulse is felt after
+compression at 120 on the scale, and the maximum oscillation occurs at
+80. The systolic pressure is 120 mm., the diastolic is 80 mm., and the
+pulse pressure is 40 mm.
+
+With the "Tycos" or Faught the arm band is snugly wound around the arm,
+the bag next to the skin and the end tucked in, so that the whole band
+will not loosen when air is forced into the bag. The cuff is blown up
+until the pulse is no longer felt. One should raise the pressure not
+more than 10 mm. above the point of obliteration of the pulse. The valve
+is then carefully opened so that the needle gradually turns toward zero.
+At the first return of the pulse wave felt at the wrist, the needle is
+sure to give a sudden jump. This is the systolic pressure and is read
+off on the scale. The needle is now carefully watched until it shows the
+maximum oscillation. This is the diastolic pressure. The difference
+between the two is, as above, the pulse pressure.
+
+In taking pressure one should take the average of several, three or
+four. Moreover, one must not take consecutive readings too quickly and
+one must be sure that between every two readings all the air is out of
+the cuff and that the mercury or dial is at zero. _It has been
+repeatedly shown that in a cyanosed arm the systolic pressure is raised
+so that even slight cyanosis between readings must be carefully
+avoided._
+
+The only accurate method of determining both the systolic and diastolic
+pressure, but especially the diastolic, is by the so-called auscultatory
+method. (See Fig. 25.) The cuff is adjusted in the usual way and one
+places the bell of a binaural stethoscope over the brachial artery from
+one to two centimeters below the lower edge of the cuff.[3] Care must
+be taken that the bell is not pressed too firmly against the arm and
+that the edge of the bell nearest the cuff is not pressed more firmly
+than the opposite end. For this purpose, one can not use the ordinary
+Bowles stethoscope or any of the other much lauded stethoscopes, because
+the surface of the bell is too large. The diameter of the bell must not
+be more than twenty-five millimeters, twenty is still better. It is
+advisable before beginning the observation to locate with the finger the
+pulse in the brachial artery just above the elbow, so that the
+stethoscope may be placed over the course of the artery. (Fig. 26.) The
+first wave which comes through is heard as a click, and occurs at a
+point on the manometer or dial scale from 5-10 mm. higher than can
+usually be palpated at the radial artery. This is the true systolic
+pressure. By keeping the bell of the stethoscope over the brachial
+artery while the pressure is falling, one comes to a point when all
+sound suddenly ceases. This is said to be the diastolic pressure. This
+is incorrect as will be shown later.
+
+ [3] A firm makes a stethoscope so that the bell is clamped on the arm
+ leaving both the operator's hands free.
+
+[Illustration: Fig. 25.--Observation by the auscultatory method and a
+mercury instrument. One hand regulates the stop cock which releases air
+gradually.]
+
+[Illustration: Fig. 26.--Observation by the auscultatory method and a
+dial instrument. The right hand holds the bulb and regulates the air
+valve.]
+
+
+=Arterial Pressure=
+
+The arterial pressure in the large arteries undergoes extensive
+fluctuations with every heart beat. The maximum pressure produced by the
+systole of the left ventricle of the heart is known as the =maximum= or
+=systolic pressure=. It practically equals the intraventricular
+pressure. The minimum pressure in the artery, the pressure at the end of
+diastole, is called the =diastolic pressure=. The difference between the
+systolic and diastolic pressures is known as the =pulse pressure=. There
+is yet another term known as the =mean pressure=. For convenience, this
+may be said to be the arithmetical mean of the systolic and diastolic
+pressures. Actually, however, this can not be the case, owing to the
+form of the pulse wave, which is not a uniform rise and fall--the
+upstroke being a straight line, but the downstroke being broken usually
+by two notches. We do not make use of the mean pressure in recording
+results. It is of experimental interest and needs only to be mentioned
+here.
+
+[Illustration: Fig. 27.--Schema to illustrate the gradual decrease in
+pressure from the heart to the vena cava: (a), arteries; (c),
+capillaries; (v), veins; (A), aorta, pressure 150 mm.; (B), brachial
+artery, pressure 130 mm.; (F), femoral vein, 20 mm.; (IVC), inferior
+vena cava, 3 mm. (Modified from Howell.)]
+
+It has been shown that the mean pressure is quite constant throughout
+the whole arterial system. The maximum pressure necessarily falls as the
+periphery of the vascular system is approached. In general it may be
+said that the minimal pressure is quite constant. Too little attention
+is paid to minimal and pulse pressure. The minimal pressure is
+important, for it gives us valuable data as to the actual propulsive
+force driving the blood forward to the periphery at the end of diastole.
+
+It is readily understood how the maximum pressure falls as the periphery
+is approached, until in the arterioles the maximum and minimum pressures
+are about equal. The pressure then in these arterioles is practically
+the same as the diastolic pressure. Actually it is a few millimeters
+less. The diastolic blood pressure would, therefore, measure the
+peripheral resistance and, as the maximum for systolic pressure
+represents approximately the intraventricular pressure, the difference
+between the two, the pulse pressure, actually represents the force which
+is driving the blood onward from the heart to the periphery. It is hence
+very evident that the mere estimation of the systolic pressure gives us
+but a portion of the information we are seeking.
+
+The pulse pressure is subject to wide fluctuations but as a rule for any
+one normal heart it remains fairly constant as the rate varies. In a
+rapidly beating heart the diastole is short and the diastolic pressure
+rises. If the systolic pressure does not also rise, as in a normal heart
+following exercise, we will say, the pulse pressure falls. We know that
+when the pulse rate is constant, vasodilatation causes a fall in
+diastolic pressure and a rise in pulse pressure. On the contrary,
+vasoconstriction causes a rise in diastolic pressure and a fall in pulse
+pressure.
+
+It is very probably the case that with two individuals of equal age and
+equal pulse rate, and equal systolic pressure of 160 mm., the one with a
+diastolic pressure of 110 mm. and, therefore, a pulse pressure of 50 mm.
+is much worse off than the other with a diastolic pressure of 90 mm. and
+a pulse pressure of 70 mm. The latter may be normal for the age of the
+person especially when certain forms of fibrous arteriosclerosis
+accompanied by enlarged heart are present.
+
+The former is not normal for any age. Low pulse pressure usually means a
+weak vasomotor control and is only found in failing circulation or in
+markedly run down states, such as after serious illness or in
+tuberculosis. Therefore, it is most important to estimate accurately the
+diastolic pressure as well as the systolic pressure, for only in this
+way can we obtain any data of value regarding the driving power of the
+heart and the condition of the vasomotor system. A high systolic
+pressure does not necessarily mean that a great deal of blood is forced
+into the capillaries. Actually it may mean that very little blood enters
+the periphery. The heart wastes its strength in dilating constricted
+vessels without actually carrying on the circulation adequately.
+
+
+=Normal Pressure Variations=
+
+The systolic pressure varies considerably under conditions which are by
+no means abnormal. Thus, the average for men at all ages is about 127
+mm. Hg. (All measurements are taken from the brachial artery, with the
+individuals in the sitting posture.) For women the average is somewhat
+lower, 120 mm. Hg. The pressure is lowest in children. In children from
+6-12 years the average systolic pressure is 112 mm. Normally, there is a
+gradual increase as age comes on, due, as will be shown in the
+succeeding chapter, to physiologic changes which take place in the
+arteries from birth to old age. In the chart here appended is
+graphically shown the normal variations in the blood pressure at
+different ages compiled from observations made on one thousand
+presumably normal persons. (Fig. 28.)
+
+[Illustration: Fig. 28.--Chart showing the normal limits of variation in
+systolic blood pressure. (After Woley.)]
+
+The diastolic pressure has been estimated to be about 35 to 45 mm. Hg
+lower than the systolic pressure, and consequently these figures
+represent the pulse pressure in the brachial artery of man. This is
+equivalent to saying that every systole of the left ventricle distends
+this artery by a sudden increase in pressure equal to the weight of a
+column of mercury 2 mm. in diameter and 35 to 45 mm. high. Naturally, at
+the heart the pressure is highest. As the blood goes toward the
+capillary area the pressure gradually decreases until, at the openings
+of the great veins into the heart, the pressure is least. At the aorta
+(A) the pressure (systolic) is approximately 150 mm. Hg, at the brachial
+artery (B) it is 130 mm., in the capillary system (C) it is 30 mm., in
+the femoral vein (F) it is 20 mm., at the opening of the inferior vena
+cava (I) it is 3 mm.
+
+Attention has been called to the normal systolic pressure at different
+ages. This is not the only cause for variations in the blood pressure.
+Normally, it is greater when in the erect position than when seated,
+and greater when seated than when lying down. During the day there are
+well-recognized changes. The pressure is lowest during the early morning
+hours, when the person is asleep. In women there are variations due to
+menstruation. Muscular exercise raises the blood pressure markedly. The
+effect of a full meal is to raise the blood pressure. The explanation is
+that during and following a meal there is dilatation of the abdominal
+vessels. This takes blood from other parts of the body, provided that
+the other factors in the circulation remain constant. A fall of
+pressure would necessarily occur in the aorta. To compensate for this,
+there is increased work on the part of the heart, which reveals itself
+as increased pressure and pulse pressure. It is well known that the
+interest in the process taken by an individual upon whom the blood
+pressure is estimated for the first time tends to increase the rate of
+the heart and to raise the blood pressure. For this reason the first few
+readings on the instrument must be discarded, and not until the patient
+looks upon the procedure calmly can the true blood pressure be obtained.
+As a corollary to this statement, mental excitement, of whatever kind,
+has a marked influence on the pressure. The patient must remain
+absolutely quiet. Raising the head or the free arm causes the pressure
+to rise. Another important physiologic variation is produced by
+concentrated mental activity. This tends to hurry the heart and increase
+the force of the beat. In short, it may be stated as a general rule that
+any active functioning of a part of the body which naturally requires a
+great excess of blood tends to elevate the blood pressure. At rest the
+pressure is constant. Variations caused by the factors mentioned act
+only transitorily, and the pressure shortly returns to normal.
+
+
+=The Auscultatory Blood Pressure Phenomenon=
+
+Since the first description of the auscultatory blood pressure sounds by
+Korotkov in 1905, this method has been more and more employed until
+today it is the standard, recognized method of determining the points in
+the blood pressure reading. When one applies the 12 cm. arm band over
+the brachial artery and listens with the bell of the stethoscope about
+one cm. below the cuff directly over the brachial artery near the bend
+of the elbow, one hears an interesting series of sounds when the air in
+the cuff is gradually reduced. The cuff is blown up above the maximum
+pressure. As the air pressure around the arm gradually is lowered, the
+series of sounds begins with a rather low-pitched, clear, clicking
+sound. This is the first phase. This only lasts through a few
+millimeters fall when a murmur is added and the tone becomes louder.
+This click and murmur phase is the second phase. A few millimeters more
+of drop in pressure and a clear, sharp, loud tone is audible. Usually
+this tone lasts through a greater drop than any of the other tones. This
+is the third phase. Rather suddenly the loud, clear tone gives place to
+a dull muffled tone. In general the transition is quite sharp and
+distinct. This is the fourth phase. The tone gradually or quickly ceases
+until no tone is heard. This is the fifth phase (Ettinger.)
+
+The first phase is due to the sudden expansion of the collapsed portion
+of the artery below the cuff and to the rapidity of the blood flow. This
+causes the first sharp clicking sound which measures the systolic
+pressure.
+
+The second, or murmur and sound phase, is due to the whorls in the blood
+stream as the pressure is further released and the part of the artery
+below the cuff begins to fill with blood.
+
+The third tone phase is due to the greater expansion of the artery and
+to the lowered velocity in the artery. A loud tone may be produced by a
+stiff artery and a slow stream or by an elastic artery and a rapid
+stream. This tone is clear cut and in general is louder than the first
+phase.
+
+The fourth phase is a transition from the third and becomes duller in
+sound as the artery approaches the normal size.
+
+The fifth phase, no sound phase, occurs when the pressure in the cuff
+exerts no compression on the artery and the vessel is full throughout
+its length.
+
+It is generally conceded that the sounds heard are produced in the
+artery itself and not at the heart.
+
+The tones vary greatly in different hearts. A very strong third tone
+phase or prolongation of this phase usually means that the heart which
+produces the tone is a strongly acting one, although allowances must be
+made for a sclerosed artery in which there is a tendency to the
+production of a sharp third phase.
+
+Weakness of the third phase, as a rule, indicates weakness of the heart
+and this dulling of the third phase may be so excessive that no sound is
+produced. Goodman and Howell have carried this method further by
+measuring the individual phases and calculating the percentage of each
+phase to the pulse pressure. Thus, if in a normal individual the
+systolic pressure is 130 mm., the diastolic 85 mm., and the pulse
+pressure 45 mm., the first phase lasts from 130 to 116 or 14 mm., the
+second from 116 to 96, or 20 mm., the third from 96 to 91 or 5 mm., the
+fourth from 91 to 85, or 6 mm. The first phase would then be 31.1 per
+cent of the total pulse pressure, the second phase 44.4 per cent, the
+third phase 11.1 per cent, and the fourth phase 13.3 per cent. They
+consider that the second and third phases represent cardiac strength (C.
+S.) and the first and fourth represent cardiac weakness (C. W.). They
+believe that C. S. should normally be greater than C. W. In the example
+above C. S.:C. W. = 55.5:44.4. In weak hearts, especially in
+uncompensated hearts, the conditions are reversed and C. W. > C. S. This
+is often the case. As a heart improves C. S. again tends to become
+greater than C. W. They think that the phases should be studied in
+respect to the sounds and also to the encroachment of one sound upon
+another.
+
+These observations are interesting but we have not found the division
+into phases as helpful as it was thought to be. We spent a great deal of
+time on this question. All that can be said, in my opinion, is that a
+loud, long third phase is usually evidence of cardiac strength.
+
+A further interesting feature which can be heard in all irregular hearts
+is a great difference in intensity of the individual sounds. Goodman and
+Howell call this phenomenon tonal arrhythmia. Irregularities can be made
+out by the auscultatory method which can not be heard at the heart.
+
+In anemia the sounds are very loud and clear and do not seem to
+represent the actual strength of the heart.
+
+The general lack of vasomotor tone in the blood vessels together with
+some atrophy and flabbiness of the coats probably explains the loud
+sounds.
+
+In polycythemia the sounds have a curious, dull, sticky character and
+can not be differentiated accurately into phases, a condition which was
+predicted from the knowledge of the sharp sounds in anemia.
+
+In not all cases can all phases be made out. It is usually the fourth
+phase which fails to be heard.
+
+In such cases the loud third tone almost immediately passes to the fifth
+phase or no sound phase. The importance of this will later be taken up.
+
+"In arteriosclerosis, with hardening and loss of elasticity of the
+vessel walls, the auscultatory phenomena, according to Krylow, are apt
+to be more pronounced, since the back pressure at the cuff probably
+causes some dilatation of the vessel above it, while the lumen of the
+vessel is smaller than normal. Both of these factors cause an increased
+rapidity in the transmission of the blood wave when pressure in the cuff
+is released, which in time favors the vibration of the vessel walls.
+
+"In high grade thickening of the arterial walls, however, especially
+where calcification had occurred, Fischer found that the sounds were
+distinctly less loud than normal, the more so in the arm, which showed
+the greater degree of hardening. According to Ettinger's experience, the
+rapidity of the flow distinctly increases the auscultatory phenomenon."
+(Gittings.)
+
+The sounds depend upon the resonating character of the cuff, upon the
+size and accessibility of the vessel, upon the force of the heart beat,
+and upon the velocity of the blood.
+
+
+=The Maximum and Minimum Pressures=
+
+The maximum (systolic) pressure is read at the point where the first
+audible click is heard after the cuff is blown up and the pressure
+gradually reduced by means of the needle valve in the hand bulb or on
+the upright of the glass containing the mercury. All are agreed upon
+this point. There has been some dispute as to the place where the
+diastolic pressure should be read. Korotkov considered that the
+diastolic pressure should be read at the fourth phase when the loud tone
+suddenly becomes dulled. Others held that the diastolic pressure should
+be read at the fifth phase, the absence of all sound. Experiments
+carried out to determine this point were made by me with the assistance
+of Prof. Eyster and Dr. Meek at the Physiological Laboratory of the
+University of Wisconsin. We arranged apparatus making it possible to
+hold the pressure in the carotid artery of dogs at maximum or minimum. A
+femoral artery was then dissected and an instrument devised to compress
+the artery with a water jacket. The whole was connected up with a
+kymograph. A time marker was put in so as to record the place where
+changes in sound were heard while listening below the cuff around the
+femoral artery. Two sets of records were taken. One with pressure
+greater than minimum pressure and a falling pressure over the femoral
+artery (Fig. 29), the other with pressure at zero and gradually raised
+to minimum pressure (Fig. 30). Both sets of records showed the same
+result; viz., that at a point corresponding to the sudden change of tone
+the pressure on the artery corresponded to the minimum pressure. It was
+therefore concluded that experimentally in dogs the point where
+diastolic pressure should be read is at the tone change from clear to
+dull, not at the point where all sound disappears.
+
+[Illustration: Fig. 29.--Tracing of auscultatory phenomena. (See
+explanation in legend of Fig. 30.)]
+
+[Illustration: Fig. 30.--Figures are to be read from left to right. The
+top line records the points where sounds were heard, the figures above
+the short vertical lines refer to tones (see text). Mx. B. P., maximum
+blood-pressure. M. B. P., minimum blood-pressure. P. B., pressure bulb
+recorder. It was impossible to lower and raise this bulb by hand without
+obtaining the great irregular oscillations of the attached lever above
+the mercury manometer. B. L., base line.]
+
+Erlanger showed some years ago, that with his instrument, the point at
+which diastolic pressure should be read was at the instant when the
+maximum oscillation of the lever suddenly became smaller. While
+checking up the graphic with the auscultatory method using Erlanger's
+instrument, it was noticed that the disappearance of all sound did not
+correspond with the sudden diminution of the oscillation of the lever
+connected with the brachial artery. A series of records were carefully
+made on patients. It was seen that during the period of the third tone
+phase the oscillations of the lever on the drum reached a maximum (Fig.
+31) and remained at approximately the same height for some millimeters
+while the pressure was gradually falling. At a point at which the third
+tone, clear and distinct, became dull, there was an appreciable decrease
+in the height of the pulse wave. From this point to the disappearance of
+all sound there was a gradual diminution of the size of the pulse
+waves.
+
+[Illustration: Fig. 31.--Fast drum. Sudden decrease in size of pulse
+wave at 4, marking the change from clear sharp tone to dull tone.]
+
+[Illustration: Fig. 32.--Slow drum. Sudden decrease in amplitude at 4.]
+
+For normal pressures the difference between the fourth (dull) tone and
+the fifth (disappearance of all tone) phase, amounted to 4 to 10 mm.
+Occasionally the difference was so little, the change from sharp third
+tone through fourth dull tone to disappearance of all sound was so
+abrupt, that one could take the disappearance of all sound as the
+diastolic pressure, with an error of not more than 2 to 4 mm. This is
+within the limits of normal error and practically may be used by those
+who have difficulty in noting the change from third to fourth phase. For
+high pressures, however, the difference between fourth and fifth phases
+was never less than 8 mm., and was found as much as 16 mm. The
+diastolic, therefore, should always be taken at the fourth phase if
+possible.
+
+It was found that with the dial instrument the greatest fling of the
+lever corresponded to the third phase and the sudden lessened amplitude
+of the oscillation was at the fourth phase and was coincident with the
+change of tone from sharp to dull. Thus the diastolic pressure may be
+read off on the dial scale by watching the fling of the hand and with
+some practice one might acquire considerable accuracy. It is better,
+simpler, and, for most observers, more accurate to use the stethoscope
+and hear the change of sound.
+
+
+=The Relative Importance of the Systolic and Diastolic Pressures=
+
+The systolic pressure represents the maximum force of the heart. It is
+measured by noting the first sound audible over the brachial artery
+using the auscultatory method. It is the summation of two factors
+largely; the force expended in opening the aortic valves (potential) and
+the force expended from that point to the end of systole, the force
+which is actually driving the blood to the periphery (kinetic). To start
+the blood in motion, the heart must overcome a dead weight equal to the
+sum of all the forces holding the aortic valves closed. This sum of
+factors, called the peripheral resistance, must be reached and passed by
+the force of the ventricular beat before one drop of blood is set in
+motion along the aorta. This factor of resistance assumes a great
+importance.
+
+The systolic pressure is always fluctuating as it depends upon so many
+conditions, and the calls of the body except during sleep are many and
+various. In a study of diurnal variations in arterial blood pressure it
+has been found that--(1) A rise of maximum pressure averaging 8 mm. of
+Hg. occurs immediately on the ingestion of food. A gradual fall then
+takes place until the beginning of the next meal. There is also a slight
+general rise of the maximum pressure during the day. (2) The range of
+maximum pressure varies considerably in different individuals, but the
+highest and lowest maximum pressures are practically equidistant from
+the average pressure of any one individual.[4]
+
+ [4] Weyse, A. W., and Lutz, B. R.: Diurnal Variations in Arterial
+ Blood Pressure, Am. Jour. Physiol., 1915, xxxvii, 330.
+
+The pressure is lowest during sleep and gradually rises near the end of
+sleep, so that on awakening the pressure was the same as before sleep.
+
+Physiologically there are many conditions which modify the systolic
+pressure. Sleep, position, meals, exercise, emotional states cause often
+wide fluctuations which may be very sudden. It should be constantly
+borne in mind, that the systolic pressure reading which is made, is the
+maximum effort of the heart at that moment only.
+
+The diastolic pressure measures the peripheral resistance. It measures
+the work of the heart, the potential energy, up to the moment of the
+opening of the aortic valves. It is the actual pressure in the aorta.
+The diastolic pressure is not very variable; it is not subject to the
+same influences which disturb the systolic pressure. It fluctuates as a
+rule, within a small range. It is not affected by diet, by mental
+excitement, by subconscious psychic influences, to anything like the
+extent to which the systolic pressure is affected by the action of
+these factors. The diastolic pressure is determined by the tone in the
+arterioles and is under the control of the vasomotor sympathetic system.
+Any agent which causes chronic irritation of the whole vasomotor system
+produces increase in the peripheral resistance with consequent rise in
+the diastolic pressure. Any agent which acts to produce thickening of
+the walls of the arterioles, narrowing their lumina, produces the same
+effect.
+
+Such states naturally result in increased work on the part of the heart,
+which as a result, hypertrophies in the left ventricle. The increase in
+size and strength is a compensatory process in order to keep the tissues
+supplied with their requisite quota of blood. Conversely, paralysis of
+the vasomotor system produces fall of diastolic pressure which, if long
+continued, results in death.
+
+The diastolic pressure then is of importance for the following reasons:
+
+1. It measures peripheral resistance.
+
+2. It is the measure of the tonus of the vasomotor system.
+
+3. It is one of the points to determine pulse pressure.
+
+4. Pulse pressure measures the actual driving force, the kinetic energy
+of the heart.
+
+5. It enables us to judge of the volume output, for pulse pressure which
+is only determined by measuring both systolic and diastolic pressure, is
+such an index.
+
+6. It is more stable than the systolic pressure, subject to fewer more
+or less unknown influences.
+
+7. It is increased by exercise.
+
+8. It is increased by conditions which increase peripheral resistance.
+
+9. The gradual increase of diastolic pressure means harder work for the
+heart to supply the parts of the body with blood.
+
+10. Increased diastolic pressure is always accompanied by increased
+pulse pressure, and increased size of the left ventricle, temporarily
+(exercise) or permanently.
+
+11. Decreased diastolic pressure goes hand in hand with vasomotor
+relaxation, as in fevers, etc.
+
+12. Low diastolic pressure is frequently pathognomonic of aortic
+insufficiency.
+
+13. When the systolic and diastolic pressures approach, heart failure is
+imminent either when pressure picture is high or low.
+
+When all these factors are taken into consideration, it becomes apparent
+that the diastolic pressure is most important, if not the most important
+part of the pressure picture.
+
+Up to within a very brief time all the statistical evidence of blood
+pressure was based on systolic readings alone. This data is most
+valuable and much has been learned as to diagnosis and prognosis, but it
+is a mass of data based on a one-sided picture and can not be as
+valuable as the statistics which will undoubtedly be published later
+when all the pressure picture figures can be analyzed.
+
+
+=Pulse Pressure=
+
+The pulse pressure is the actual head of pressure which is forcing the
+blood to the periphery. At every systole a certain amount of blood 75-90
+c.c. (Howell) is thrown violently into an already comfortably filled
+aorta. The sudden ejection of this blood instigates a wave which rapidly
+passes down the arteries as the pulse wave. The elastic recoil of the
+aorta and large arteries near the heart contract upon the blood and keep
+it moving during diastole. Normally the blood-vessels are highly elastic
+tubes with an almost perfect coefficient of elasticity. The pulse
+pressure varies under normal conditions from 30 to 50 mm. Hg. There is a
+very definite relationship between the velocity of blood and the pulse
+pressure which is expressed thus; velocity = pulse rate x pulse
+pressure.[5]
+
+Further it has been demonstrated that under normal conditions and during
+various procedures--the pulse pressure is a reliable index of the
+systolic output.[6]
+
+ [5] Erlanger and Hooker: An Experimental Study of Blood Pressure and
+ of Pulse Pressure in Man, Johns Hopkins Hosp. Rep., 1904, xii, 145.
+
+ [6] Dawson and Gorham: The Pulse Pressure as an Index of Systolic
+ Output, Jour. Exper. Med., 1908, x, 484.
+
+Increased pulse pressure therefore goes hand in hand with greater
+systolic output. Physiologically this is most ideally seen during
+exercise. Following exercise the pulse rate increases, the systolic
+pressure rises greatly, the diastolic slightly or not at all. The pulse
+pressure therefore is increased. The velocity also is much increased.
+The call comes for more blood and the heart responds. In the chronic
+high pulse pressures there are four correlated conditions which, so far
+as I have studied them, are always present. These are: (1) An increase
+in size of the cavity of the left ventricle. The ventricle actually by
+measurement contains more blood than normal, and therefore throws out
+more blood at every systole. The volume output is greater per unit of
+time. (2) There is actual permanent increase in diameter of the arch of
+the aorta. This is a compensating process to accommodate the increased
+charge from the left ventricle. (3) There are on careful auscultation
+over the manubrium, particularly the lower half, breath sounds which
+vary from bronchial to intensely tubular, depending upon the anatomic
+placing of the aorta, the shape of the chest, and the degree of
+dilatation. Often there is very slight impairment of the percussion note
+as well. (4) There is increase in size of all the large distributing
+arteries, carotids, brachials, femorals, renals, celiac axis, etc., with
+fibrous changes in the media, loss of some elasticity, and increase in
+size of the pulse wave. Increased pulse pressure means increased volume
+output, but does not always mean increased velocity. The proper
+distribution of blood to the various organs of the body is regulated by
+the vasomotor system acting upon the small arteries which contain
+considerable unstriated muscle. When fibrous arteriosclerosis is present
+there is loss of elasticity in the distributing arteries and a greater
+volume of blood must be thrown out by the ventricle at every systole in
+order that every organ shall have its full quota of blood. A force which
+is sufficient to send blood through elastic normal distributing tubes
+becomes totally insufficient to send the same amount of blood through
+tortuous and more or less inelastic tubes.
+
+It is evident then that pulse pressure is exceedingly important. It can
+only be determined by measuring both the _systolic_ and _diastolic_
+pressure. The pulse rate must also be known in order to compute the
+velocity. It is essential to have the whole pressure picture for all
+cases if correct conclusions are to be drawn.
+
+In an irregular heart, especially in the cases due to myocardial
+disease, it is quite impossible to determine the true diastolic
+pressure. One can only approximate it and say that the pulse pressure is
+low or high. As a matter of fact the real systolic pressure can not be
+determined. For this figure the place on the scale where most of the
+beats are heard may be taken for the average systolic pressure. No one
+can seriously maintain that he can measure the diastolic pressure under
+all circumstances.
+
+By means of the auscultatory method of measuring blood pressure we are
+able to determine irregularities of force in the heart beats more easily
+than by listening to the heart sounds. A pulsus alternans is readily
+made out. The irregular tones heard over the brachial artery in cases of
+irregular heart action have been called "tonal arrhythmias."
+
+
+=Blood Pressure Variations=
+
+A recent study of diurnal variations in blood pressure has shown that
+while the maximum pressure rises after the ingestion of food and
+steadily rises slightly throughout the day, the minimum blood pressure
+is very uniform throughout the day, and is little affected by the
+ingestion and digestion of meals. When it is affected, a rise or a fall
+may take place. Throughout the day, it tends to become slightly lower.
+The pulse pressure then is greater towards evening.
+
+Weysse and Lutz in a study of this question draw the following
+conclusions:
+
+1. A rise of maximum pressure averaging 8 mm. of Hg occurs immediately
+on the ingestion of food. A gradual fall then takes place until the
+beginning of the next meal. There is also a slight general rise of the
+maximum pressure during the day.
+
+2. The average maximum blood pressure for healthy young men in the
+neighborhood of 20 years of age is 120 mm. of Hg. This pressure obtains
+commonly one hour after meals. The higher maximum pressures occur
+immediately after meals, and the lower, as a rule, immediately before
+meals.
+
+3. The range of maximum pressure varies considerably in different
+individuals, but the highest and lowest maximum pressures are
+practically equidistant from the average pressure of any one individual.
+
+4. The minimum blood pressure is very uniform throughout the day, and is
+little affected by the ingestion and digestion of meals. When it is
+affected a rise or fall may take place. There is a tendency for a slight
+general lowering of the minimum pressure throughout the day.
+
+5. The average minimum blood pressure for healthy young men in the
+neighborhood of 20 years of age is 85 mm. of Hg. Thus we get an average
+pulse pressure of 35 mm. of Hg.
+
+6. Pulse pressure, pulse rate, and the relative velocity of the blood
+flow are increased immediately upon the ingestion of meals. They attain
+the maximum, as a rule, in half an hour, and then decline slowly until
+the next meal. There is a general increase in each throughout the day.
+
+These measurements were made upon persons at rest. Almost any form of
+exercise would have made the variations much greater. No account is
+taken of the psychic variations which for the physician are the most
+important to bear in mind. Neglect to take this variation into account
+will inevitably lead to false conclusions.
+
+THE AVERAGE DIURNAL BLOOD PRESSURE RECORD OF THE TEN SUBJECTS
+
+==========+=======+=======+=======+=======+========+=======+===============
+ TIME |MAXIMUM|MINIMUM| MEAN | PULSE | PULSE |PP x PR| NOTES
+ | | | | |PRESSURE| RATE |
+----------+-------+-------+-------+-------+--------+-------+---------------
+ |_mm._Hg|_mm._Hg|_mm._Hg|_mm._Hg| | |
+4:30 p.m. | 119.5 | 84.1 | 101.8 | 35.4 | 72.0 | 2549 |
+5:00 p.m. | 117.7 | 83.5 | 100.6 | 34.2 | 71.1 | 2432 |
+6:00 p.m. | 118.0 | 84.0 | 101.0 | 34.0 | 74.9 | 2547 |Before dinner
+6:45 p.m. | 127.2 | 88.2 | 107.7 | 39.0 | 78.1 | 3046 |After dinner
+7:00 p.m. | 124.7 | 87.7 | 106.2 | 37.0 | 76.0 | 2812 |
+7:30 p.m. | 122.0 | 83.4 | 102.7 | 38.6 | 76.0 | 2934 |
+8:00 p.m. | 122.4 | 85.5 | 103.4 | 36.9 | 71.2 | 2527 |
+8:30 p.m. | 120.0 | 85.0 | 102.5 | 35.0 | 69.7 | 2439 |
+9:00 p.m. | 120.5 | 84.7 | 102.5 | 35.8 | 65.2 | 2334 |
+9:30 p.m. | 118.2 | 84.4 | 101.6 | 33.8 | 64.4 | 2177 |
+7:30 a.m. | 118.4 | 87.6 | 103.0 | 30.8 | 70.3 | 2165 |
+8:00 a.m. | 116.4 | 86.4 | 101.4 | 30.0 | 69.8 | 2094 Before breakfast
+8:30 a.m. | 124.2 | 85.4 | 104.8 | 38.8 | 79.4 | 3081 |After breakfast
+9:00 a.m. | 123.8 | 84.4 | 104.1 | 39.4 | 84.1 | 3313 |
+10:00 a.m.| 118.2 | 83.6 | 100.9 | 34.6 | 70.7 | 2446 |
+11:00 a.m.| 116.2 | 84.8 | 100.5 | 31.4 | 67.7 | 2126 |
+12:00 m | 114.4 | 83.2 | 98.8 | 31.2 | 66.2 | 2065 |Before luncheon
+12:30 p.m.| 122.8 | 83.2 | 103.0 | 39.6 | 70.9 | 2808 |After luncheon
+1:00 p.m. | 122.3 | 82.0 | 102.1 | 40.3 | 79.7 | 3212 |
+2:00 p.m. | 118.4 | 81.4 | 99.9 | 37.0 | 77.6 | 2871 |
+3:00 p.m. | 118.8 | 82.6 | 100.7 | 36.2 | 75.1 | 2719 |
+4:00 p.m. | 115.8 | 82.0 | 98.9 | 33.8 | 71.9 | 2420 |
+5:00 p.m. | 117.2 | 83.4 | 100.3 | 33.8 | 69.6 | 2352 |
+6:00 p.m. | 117.4 | 84.4 | 100.9 | 33.0 | 72.8 | 2402 |Before dinner
+6:45 p.m. | 124.6 | 83.1 | 103.8 | 41.5 | 80.4 | 3337 |After dinner
+7:00 p.m. | 125.2 | 84.2 | 104.7 | 41.0 | 76.1 | 3120 |
+7:30 p.m. | 122.0 | 84.0 | 103.0 | 38.0 | 73.7 | 2801 |
+8:00 p.m. | 119.6 | 85.0 | 102.3 | 34.6 | 72.3 | 2502 |
+8:30 p.m. | 119.7 | 84.0 | 101.3 | 34.7 | 69.0 | 2394 |
+9:00 p.m. | 120.0 | 86.2 | 103.1 | 33.8 | 68.0 | 2298 |
+ +-------+-------+-------+-------+--------+-------+
+ Average | 120.0 | 85.0 | 102.5 | 35.0 | 72.0 | 2550 |
+----------+-------+-------+-------+-------+--------+-------+---------------
+ (Taken from Weysse and Lutz.)
+
+In some experiments to determine the changes upon the blood pressure
+induced by hot and cold applications on and within the abdomen, Hammett,
+Tice and Larson found that heat applied to the outside of the abdomen
+raises the blood pressure. The application of cold produces no change.
+Either hot or cold saline introduced within the abdomen causes a fall in
+blood pressure.
+
+Experimentally, certain drugs such as adrenalin, barium chloride,
+nicotine, digitalis, strophanthus and the infundibular portion of the
+pituitary body known as pituitrin raise the maximum pressure. In the
+clinic it is difficult to conclude always whether the drug alone is
+responsible for rise in maximum pressure. Adrenalin given intravenously
+will raise the pressure. So will digitalis and strophanthus. I have
+watched the maximum pressure rise within three minutes following an
+intravenous injection of gr. 1/100 (0.0006 gm.) strophanthin 20 mm. of
+Hg: I have seen the subcutaneous injection of 10 minims of adrenalin
+repeated several times daily for six months fail to have the least
+effect on the blood pressure picture.
+
+Elevation of the foot of the bed about nine inches proved so efficacious
+in steadying failing hearts in acute infectious diseases, particularly
+typhoid, that a study was made of the effect upon blood pressure. Many
+observations were made, but no instrumental proof of rise in blood
+pressure could be adduced.
+
+Exercise always raises blood pressure, the maximum much more than the
+minimum. In athletes the minimum pressure may actually fall, the maximum
+rise so that a greater volume output results from the greater pulse
+pressure.
+
+Shock and hemorrhage lower it. Hemorrhage lowers also the pulse
+pressure, and it may be possible to prognosticate internal hemorrhage by
+frequent estimations of the systolic and diastolic pressures (Wiggers).
+Compression of the superior mesenteric artery or the celiac axis in dogs
+raises the blood pressure measured in the carotid artery for a period of
+at least an hour. This seems to be dependent on purely mechanical
+causes, and is not a reflex vasomotor phenomenon. (Longcope and
+McClintock.)
+
+Experimentally blood pressure can be increased by direct compression of
+the brain as Cushing has shown. It was thought at one time that in man
+the same effect would result from tumor of the brain or especially from
+subdural or extradural hemorrhage following head injuries. This,
+however, is not the case. No information of great value can be obtained
+by the measurement of blood pressure in these states. We do know that
+too high and too prolonged compression of the medulla brings about
+exhaustion of the cardiac center accompanied with rapid pulse, low
+pressure and eventual death.
+
+
+=Hypertension=
+
+All the conflict during the past few years over the subject of blood
+pressure has revolved around this much overworked word. Hypertension
+means high pressure, and yet it carries with it a suggestion of high
+pressure which is harmful to the individual. As a matter of fact
+hypertension is a compensatory process, it is often a saving process in
+spite of the fact that it carries possibilities of harm in its
+possessor. It has been made a fetish, a god to fall down before and
+worship and it has been the means of holding a torch of fear over a
+patient which has not been lost on the charlatans. Popularization of
+blood pressure has brought its crop of evils, no one of which has been
+as fruitful in dollars to unprincipled quacks as hypertension.
+
+Hypertension is the expression on the part of the circulation to meet
+new conditions in the tissues so that all tissues will be nourished and
+all will be enabled to function. Looked at from that point of view it is
+a conservative process and in many cases it is. It is not an average
+normal state, but it is normal state for the man who has it in chronic
+form. Hypertension should be viewed rationally and its proper place in
+the whole make-up of the patient determined. Hypertension is a relative
+term. What might be high pressure in a man of sedentary habits who
+reaches the age of fifty, might not be high pressure in a full blooded
+formerly athletic man of the same age. Temporary hypertension due to
+excitement, exercise, etc., must be kept in mind. It is not intended to
+convey the impression that hypertension is of no moment. It is a matter
+for investigation, but not a matter to worship as the all-in-all.
+
+Hypertension is, after all, a physiologic response on the part of the
+organism in order to maintain the circulation in equilibrium in the face
+of conditions which tend to produce vasoconstriction in large areas and,
+therefore tend to deprive these areas of blood. That there must be some
+substance in the blood stream which causes this constriction seems
+certain. What it is, is not at present known. Recently, Voegtlin and
+Macht[7] have isolated a crystalline substance from the blood of man and
+other mammals which they regard as a lipoid and closely related to
+cholesterin. This substance was recovered by them from the cortex of the
+adrenal gland. This becomes of added interest in the light of
+observations made by Gubar (quoted by Voegtlin and Macht). He noted
+"that the vasoconstricting properties of blood serum vary in different
+pathologic conditions, being increased in nephritis, for instance, and
+diminished in others." In some experiments made in the summer of 1913,
+we found there was no marked difference in the anaphylactic shock
+produced in half-grown rabbits by the injection of normal and uremic
+blood serum. As lipoids do not cause anaphylaxis, there should be no
+difference in the reaction of normal and uremic sera unless in one there
+was some form of protein not in the other. This does not seem to be the
+case. The presence of something in the circulation, therefore, produces
+constriction of vessels. This calls for more force in contraction on the
+part of the heart. This substance may be of lipoid nature. The continued
+presence of this hypothetical substance naturally would lead to
+hypertrophy of the heart.
+
+ [7] Isolation of a New Vasoconstrictor Substance from the Blood and
+ the Adrenal Cortex, Jour. Am. Med. Assn., 1913, lxi, 2136.
+
+What makes hypertension of significance is not the hypertension itself,
+but the fact that it is the expression of processes going on in the
+body which demand exhaustive investigation. To attach a blood pressure
+cuff to the arm, find the pressure, and diagnose hypertension is like
+putting a thermometer under the tongue, noting a rise in the mercury,
+and diagnosing fever. What causes the hypertension? Can the causes be
+removed? Those are the really vital questions after the symptom
+hypertension has been discovered.
+
+All states of hypertension are accompanied by more or less increase of
+pulse pressure. In other words the systolic pressure is always increased
+to greater degree than the diastolic pressure. In studies carried out in
+the wards and Pathological Laboratory of the Milwaukee County Hospital,
+Milwaukee, we found that in all of the cases of chronic high blood
+pressure with resulting high pulse pressure four correlated factors were
+found. If any one of these factors is present, the other three are
+found.
+
+1. In all high pulse pressure cases there is increase in the size of the
+cavity of the left ventricle. The ventricle actually contains more blood
+when it is full, and throws out, therefore, more blood at each systole.
+The actual volume output is greater per unit of time. Such hearts always
+show increase in thickness of the ventricular wall. I quite agree with
+Stone,[8] who says, "It is merely to be emphasized that when the pulse
+pressure persistently equals the diastolic pressure (high pressure
+pulse, in other words) with a resulting 50 per cent, _overload_, which
+means the expenditure of double the normal amount of kinetic energy on
+the part of the heart muscle, cardiac hypertrophy has occurred." They
+are found in aortic insufficiency, in chronic nephritis, in the diffuse
+fibrous type of arteriosclerosis, and in some cases of exophthalmic
+goiter. Such a condition occurs temporarily after exercise.
+
+ [8] Stone, W. J.: The Differentiation of Cerebral and Cardiac Types of
+ Hyperarterial Tension in Vascular Diseases, Arch. Int. Med., November,
+ 1915, p. 775.
+
+2. In all high pulse pressure cases there is actual permanent increase
+in diameter of the arch of the aorta. This is a compensating process to
+accommodate the increased charge from the left ventricle. Smith and
+Kilgore[9] have shown this to be true in cases of chronic nephritis with
+hypertension. Their research confirms my own observations. They found
+dilatation of the arch in (1) syphilis (that is, aortitis); (2) age over
+50 (that is, probable factor of arteriosclerosis); (3) other serious
+cardiac enlargement, and (4) hypertension (with more or less
+hypertrophy, as in chronic nephritis).
+
+ [9] Smith, W. H., and Kilgore, A. R.: Dilatation of the Arch of the
+ Aorta in Chronic Nephritis with Hypertension, Am. Jour. Med. Sc.,
+ 1915, cxlix, 503.
+
+In ten cases showing arches at the upper limit of normal (that is, 6 cm.
+in diameter) and hypertrophy of the heart, three were chronic mitral
+endocarditis; one was chronic aortic endocarditis; three were chronic
+mitral and aortic endocarditis, and there was one each of
+hyperthyroidism, pericarditis and adherent pericardium.
+
+In fourteen cases of hypertension (highest systolic 270 mm., average
+systolic, 215 mm.), all showed cardiac hypertrophy. "All but three of
+these cases had great vessels whose transverse diameters measured over
+the normal limit of 6 cm., and in one of those measuring 6 cm. the
+Roentgen-ray diagnosis was 'slight dilatation' of the arch." Smith and
+Kilgore are at a loss to explain the three exceptions. They did not give
+diastolic pressures, so pulse pressures are not known. Possibly the
+three exceptions were cases of high diastolic pressure in which the
+pulse pressure possible was not over 60 mm. Such cases might show
+"slight dilatation of the arch," but not marked dilatation, such as was
+found in the other, evidently high pulse pressure cases.
+
+We have found that only the high pulse pressure cases show dilatation of
+the arch. Certain high tension cases which have had a very high
+diastolic pressure do not reveal any accurately measurable dilatation of
+the aortic arch. An empty aorta after death is quite different from a
+functionating aorta during life. Hence the dilatation which is found
+postmortem must have been considerable during life. And conversely, a
+dilatation which was present during life might not be looked on as such
+after death.
+
+3. In all high pulse pressure cases one will find on careful
+auscultation over the manubrium, particularly its lower half, breath
+sounds which vary from bronchial to intensely tubular. At times the
+percussion note will be slightly impaired, as McCrae[10] has shown in
+dilatation of the arch of the aorta. This auscultatory sign is evidence
+of some more or less solid body in the anterior mediastinum which is
+lying on the trachea and permits the normal tubular breathing in the
+trachea to be audible over the upper part of the sternum. It is found in
+cases of dilated aortic arch. Fluoroscopic examination has confirmed the
+findings on auscultation.
+
+ [10] McCrae, Thomas: Dilatation of the Arch of the Aorta, Am. Jour.
+ Med. Sc., 1910, cxl, 469.
+
+4. In all high pulse pressure cases, in which the pulse pressure is over
+70 mm. of mercury, there is increase in the size of all large
+distributing arteries, carotids, brachials, femorals, renals, celiac
+axis, etc., with fibrous changes in the media, loss of some of the
+elasticity, and in the palpable superficial arteries, increase in size
+of the pulse wave.
+
+Increased pulse pressure means increased volume output, but does not
+always mean increased velocity. The proper distribution of blood to the
+various organs of the body is regulated by the vasomotor system acting
+on the small arteries which contain considerable unstriated muscle. In
+order that there may be enough blood at all times and under varying
+conditions of rest and function, there must be a proper supply coming
+through the distributing vessels, the large arteries, those containing
+much elastic tissue, and only a very small amount of unstriated muscle
+tissue or none whatever. Fibrous sclerosis of these vessels causes them
+to become enlarged and tortuous and to lose much of their elasticity,
+which is essential for the even distribution of blood. A greater blood
+volume is therefore necessary in order that the organs may receive their
+quota of blood. A force which is sufficient to send blood through
+elastic normal distributing tubes becomes totally insufficient to send
+the same amount of blood through tortuous and more or less inelastic
+tubes. As a compensatory process the pulse pressure increases. For this
+to increase, the left ventricular cavity dilates, the arch dilates, and
+as a greater force must be exerted to keep the increased mass in motion,
+the heart responds by hypertrophy of its left ventricle and becomes
+itself the subject of fibrous changes in the myocardium. The mass
+movement of blood is therefore greater in high pulse pressure cases than
+in cases of normal pulse pressure.
+
+In cases of chronic interstitial nephritis--contracted granular
+kidney--it may well be that the sclerosis of the arteries is a secondary
+process caused, as Adami thinks, by the hypertension itself. In aortic
+insufficiency the situation is somewhat different. The high pulse
+pressure is due to a very low diastolic pressure, for in my experience
+with uncomplicated aortic insufficiency the systolic pressure is, as a
+rule, not much increased above the normal for the individual's age. Here
+peripheral resistance is so low that a capillary pulse is common. The
+volume output per unit of time is greatly increased, the arch of the
+aorta is dilated, and the pulse is large. The fact that a large part of
+the blood regurgitates during diastole back into the ventricle, and the
+fact that the diastolic pressure is low means that there is no increased
+resistance to overcome, and the systolic pressure is not raised.
+
+Stone[11] has divided the cases of hypertension into the cerebral and
+cardiac types. He finds that there is a difference in prognosis and in
+the mode of death in the two groups. He has further attempted to judge
+of the work placed upon the heart by calculating what he calls the
+heart load or pressure-ratio. For example, he takes a normal pressure at
+120-80-40. The relation between 80 and 40 is 1/2 or 50 per cent. That he
+considers normal. When the heart load increases so that the pulse
+pressure equals or exceeds the diastolic pressure, the heart load is 100
+per cent or more, he considers the danger of myocardial exhaustion
+graver than when the heart load is normal or less than 50 per cent.
+
+ [11] Stone, W. J.: Arch. Int. Med., 1915, xvl, 775.
+
+It is his opinion, in which I heartily concur, "that an individual with
+a systolic pressure of 200 and a diastolic pressure of 140, is in
+greater danger of cerebral death than an individual with a systolic
+pressure of 200 and a diastolic pressure of 100." He is "likewise
+certain that the individual with a systolic pressure of 200 and a
+diastolic of 90 to 100 is in greater danger of a cardiac death. It is
+apparently the constant high diastolic pressure rather than the
+intermittently high systolic pressure which predisposes to cerebral
+accident."
+
+I have not been able to confirm all of Stone's conclusions. His
+contention holds good for some cases, but not, in my experience, for the
+great majority of the hypertension cases. I feel that in the
+classification of the chronic high pressure case we can go one step
+farther and split his first group into two usually differentiable
+groups. Syphilis is not an etiological factor in any of these groups. It
+is not considered that these groups are absolutely distinct and can
+always be rigidly separated. There are variations and combinations which
+render an exact separation impossible. But bearing this in mind the
+following classification is proposed as a working classification.
+
+Group A. Chronic nephritis.
+
+Group B. Essential hypertension.
+
+Group C. Arteriosclerotic hypertension.
+
+Group A. _Chronic Nephritis._ These are the cases with a high-pressure
+picture, that is to say, high systolic (200+) and high diastolic
+(120-140+). The pulse pressure is much increased. The palpable arteries
+are hard and fibrous. There is puffiness of the under eyelids, which is
+more pronounced in the morning on arising. Polyuria with low specific
+gravity and nycturia are present. There are almost constant traces of
+albumin in the urine, with hyaline and finely granular casts.
+
+Functionally these kidneys are much under normal. The functional
+capacity determined by Mosenthal's modification of the Schlayer-Hedinger
+method shows a marked inability to concentrate salts and nitrogen. The
+phthalein output is below normal. As the case advances the phthalein
+output becomes less and less, until a period is reached when there are
+only traces or complete suppression at the end of a two-hour period.
+Such patients may live for ten weeks (one of our cases) or longer, all
+the time showing mild uremic symptoms, and suddenly pass into coma and
+die.
+
+The natural end of patients in this group is either uremia or cardiac
+decompensation (so-called cardiorenal disease). Cerebral accidents may
+happen to a small number. It is only to this group, in my opinion, that
+the term cardiorenal disease should be applied. Formerly I believed that
+all high systolic pressure cases were cases of chronic nephritis of some
+definite degree. From the purely pathologic standpoint that is true, but
+from the important, functional standpoint it is far from being the true
+state of the cases.
+
+In this group there is marked hypertrophy and moderate dilatation of the
+left ventricle with dilatation and nodular sclerosis of the aorta. The
+kidneys are firm, red, small, coarsely granular, the cortex much
+reduced, the capsule adherent. Cysts are common. It is the familiar
+primary contracted kidney. Mallory calls this capsular-glomerulonephritis.
+The etiology is obscure. Often no cause can be found. Again, there is a
+history of some kidney involvement following one of the acute infectious
+diseases, or it may follow the nephritis of pregnancy. Usually, however,
+these cases fall into the group of secondary contracted kidneys, chronic
+parenchymatous nephritis.
+
+ Illustrative Case.--R. Z., a woman, aged thirty-six years, was seen
+ July 26, 1916, in coma. There was a history of typhoid fever at
+ nineteen years, but no other disease. She had had nine full-term
+ pregnancies, the last one thirteen months previously. For a week
+ before the onset of the present illness she had complained of severe
+ headaches and dizziness. There were no heart symptoms. For the past
+ year she has had nycturia. Physical examination revealed tubular
+ breathing beneath the manubrium, a few rales in the chest, an
+ enlarged heart (left side), with a systolic murmur over the aortic
+ area. Blood pressure was 178-125-53, the pulse rate 96, leucocytes
+ 27,250. Venesection of 500 c.c. of blood and intravenous injections
+ of 500 c.c. of 5 per cent NaHCO_3 in normal saline were employed.
+ Lumbar puncture withdrew 60 c.c. of clear fluid under pressure with
+ 6 cells per cubic millimeter. The eye grounds showed distinct
+ haziness of the disks and dilatation of the veins. Blood pressure
+ after venesection was 164-122-42, pulse 76, but in a few days rose
+ to 222-142-80, pulse 70. A second venesection of 400 c.c. and
+ proctoclysis of 1000 c.c. saline solution was tried. The
+ blood-pressure now was 198-140-58. The pH of the blood was 7.6, the
+ alkaline reserve was 35 volume per cent (van Slyke), and the CO_2
+ tension of the alveolar air (Marriott) was 25 mm. The phthalein on
+ the day following the second venesection was 45 per cent in two
+ hours. The urine at first showed 500 c.c. in twenty-four hours,
+ specific gravity 1016, albumin and casts. Later she passed 1300 to
+ 1600 c.c. with specific gravity around 1010. The blood-pressure
+ fluctuated considerably, reaching as low as 138-98-40, pulse 88. She
+ was discharged improved September 10, 1916. She had constant
+ headache but managed to keep up. In June, 1917, she suddenly died in
+ an uremic coma.
+
+Group B. This one might designate as the hereditary type, although there
+is not always a history in the antecedent. This group includes the
+robust, florid, exuberantly healthy people. They often are heard to
+boast that they have never had a doctor in their lives. They are usually
+thick-set or very large, fleshy people. The pressure picture is
+exceedingly high. The pulse pressure is moderately increased. The
+arteries are rather large, fibrous, and often quite tortuous, although
+this is not always the case. Some persons have hard, small, fibrous
+arteries. There is no puffiness beneath the eyes, no polyuria, and no
+nycturia as a rule. The urine is of normal amount, color, and specific
+gravity. Albumin is only rarely found and then in traces, but careful
+search of a centrifuged specimen invariably reveals a few hyaline
+casts. The phthalein excretion is normal or only slightly reduced. The
+kidneys excrete salt and nitrogen normally. It is in this group that
+apoplexy is found most frequently. The rupture of the vessel occurs when
+the victim is in perfect health, often without any warning. Occasionally
+when such a case recovers sufficiently to be around, cardiac
+decompensation sets in later and he dies then of the cardiac
+complications.
+
+Pathologically the hearts of such persons are found to have the most
+enormous hypertrophy of the wall of the left ventricle. The cavity is
+somewhat enlarged, as is always the case when the pulse-pressure is
+increased, but the size of the cavity is not the striking feature. The
+aorta is fibrous, thick walled, and the arch is slightly dilated. There
+are patches of arteriosclerosis. One such case seen only at autopsy had
+a rupture of the aorta just above the sinus of Valsalva and died of
+hemopericardium. The kidneys are of normal size, dark red, firm, the
+capsule strips readily, the surface is smooth or finely granular, the
+cortex is not decreased. The pyramids are congested and red streaks
+extend into the cortex. Microscopically the capsules of the glomeruli
+are a trifle thickened; a few show hyaline changes. There is rather
+diffuse, mild, round-cell infiltration between the tubules. The tubular
+epithelium shows little or no demonstrable changes. The arterioles are
+generally the seat of a moderate thickening of the intima and media, but
+it is not usual to find obliterating endarteritis. There is evidently a
+diffuse fibrous change which has not affected either the tubules or
+glomeruli to any great extent.
+
+ Illustrative Case.--L. C., a man, aged fifty-six years, stonemason
+ by trade, is a stocky, thick-necked individual. He had never been
+ ill in his life until a year ago, when he fell from his chair
+ unconscious. He had a right-sided hemiplegia which has cleared up so
+ completely that except for a very slight drag to his foot he walks
+ perfectly well. He came in complaining of shortness of breath and
+ cough. There was no swelling of the feet. Here evidently was
+ left-heart decompensation. Examination showed the blood pressure to
+ be 240-130-110, pulse irregular, 104 to the minute. There were
+ cyanosis and rales throughout both chests. The urine was normal in
+ color, specific gravity 1025, small amount of albumin, few casts,
+ hyaline and granular. The phthalein elimination was 65 per cent in
+ two hours. Under rest, purgatives, and digitalis he was much
+ improved. He has since had two other apoplectic strokes, the last of
+ which was fatal.
+
+When these patients are seen with acute cardiac decompensation, there
+are, of course, much albumin and many casts in the urine, and the
+phthalein output is, for the time being, decreased.
+
+Group C. This might be called the arteriosclerotic high-tension group
+(Stone's cardiac group). The cases are usually over fifty years old.
+They are men and women who have lived high and thought hard. Often they
+have had periods of great mental strain. Many men in this group were
+athletes in their young manhood. Many have been fairly heavy drinkers,
+although never drinking to excess. They are usually well nourished and
+inclined to stoutness. The pressure picture is high systolic with normal
+or only slightly increased diastolic and large pulse pressure. The
+arteries are large, full, fibrous, usually tortuous. The heart is very
+large, the apex far down and out. There is no polyuria; nycturia is
+uncommon, quite the exception. The urine is normal in color, amount, and
+specific gravity. Albumin is only rarely found and hyaline casts are not
+invariably present. The phthalein excretion is quite normal and the
+excretions of salt and nitrogen are also normal. The terminal condition
+in most of the patients in this group is cardiac decompensation. They
+may have several attacks from which they recover, but after every attack
+the succeeding one is produced by less exertion than the preceding one,
+and it becomes more and more difficult to control attacks. Eventually
+the patients become bed- or chair-ridden, and finally die of acute
+dilatation of the heart.
+
+Occasionally patients in this group may have a cerebral attack, but in
+my experience this is uncommon. Pathologically the heart is large, at
+times true _cor bovinum_, dilated and hypertrophied. The cavity of the
+left ventricle is much dilated. The aorta is dilated and sclerosed.
+
+The kidneys are increased in size, are firm, dark red in color, with
+fatty streaks in the cortex. The capsule strips readily and the cortex
+is normal in thickness or only slightly increased. The organ offers some
+resistance to the knife. The microscope shows small areas scattered
+throughout where the glomeruli are hyalinized, the stroma full of small
+round cells, the tubules dilated, and the cells are almost bare of
+protoplasm. Naturally the tubules are full of granular cast material.
+Also the arterioles show extensive intimal thickening, fibrous in
+character, with occasional obliterating endarteritis. One gets the
+impression that the small sclerotic lesions are the result of anemia and
+gradual replacement of scattered glomeruli by fibrous tissue. For the
+most part the kidney, except for the chronic passive congestion, appears
+quite normal. One can readily understand that in such a kidney function
+could not have been much interfered with.
+
+ Illustrative Case.--C. K., an active, stout, business man, aged
+ fifty-six years, consulted me on account of shortness of breath and
+ swelling of the feet in May, 1915. He had just returned from a
+ hospital in another city, where he had gone with what was apparently
+ cardiac decompensation. In his early manhood he had been a gymnast
+ and a prize winner. He has worked hard, often given way to violent
+ paroxysms of temper, has eaten heavily but drunk very moderately.
+ The heart was greatly enlarged, the arch of the aorta dilated, a
+ mitral murmur was audible at the apex. The radials and temporals
+ were large, tortuous, and fibrous. The blood pressure picture ranged
+ around 180-90-90. He was easily made dyspneic and had a tendency to
+ swelling of the lower legs. The urine was acid, of normal specific
+ gravity, normal in amount, normal phthalein, normal concentration of
+ salt and nitrogen, contained albumin only when he was suffering from
+ decompensation of the heart. Casts were always found. He finally
+ died, after sixteen months, with all the symptoms of chronic
+ myocardial insufficiency. The heart was enormous, a true _cor
+ bovinum_. The kidneys were typical of this condition, possibly
+ somewhat larger than usual.
+
+
+=Hypotension=
+
+When the pressure is constantly below the normal, it is called
+hypotension. This may be transient--as in fainting--it may be a normal
+state of the individual, it occurs in most fevers and in a great
+variety of diseases, including anemias.
+
+In arteriosclerosis, especially the diffuse (senile) type, the blood
+pressure is invariably low, and may be spoken of as hypotension. The
+heart in such a case is small, the muscle is flabby, there is brown
+atrophy of the fibers, and some replacement of the muscle cells by
+connective tissue. The same causes which have produced general
+arteriosclerosis have also produced sclerosis of the coronary arteries,
+and probably the lessened blood supply accounts for much of the atrophy
+of the heart muscle.
+
+In typhoid fever the maximum blood pressure during beginning
+convalescence may be as low as 65 mm. Hg. I have frequently seen
+hypotension of 80 mm. This is common.
+
+Meningitis is the only acute infectious disease in which the blood
+pressure is more often high than low. This is accounted for by the
+increased intracranial tension.
+
+Following large hemorrhages the blood pressure is reduced. In
+venesection the withdrawal of blood may not affect the blood pressure.
+The procedure is done to relieve overdistension of the heart.
+
+In pleurisy with effusion and in pericarditis with effusion there is
+hypotension.
+
+Collapse, whether from poisoning by drugs or as the result of dysentery,
+cholera, or profuse vomiting from whatever cause, reduces the blood
+pressure.
+
+In cachectic states, such as cancer, the blood pressure is low. General
+wasting of the whole musculature includes that of the heart and the
+heart muscle shows the condition known as "brown atrophy."
+
+A most interesting and important condition in which hypotension occurs
+is pulmonary tuberculosis. Haven Emerson has recently gone over the
+whole subject in a careful piece of work and his summary is as follows:
+
+"Hypotension or subnormal blood pressure is universally found in
+advanced pulmonary tuberculosis, in which condition emaciation may play
+a part in its causation. Hypotension is found in almost all cases of
+moderately advanced tuberculosis, or in early cases in which the toxemia
+is marked except when arteriosclerosis, the so-called arthritic or gouty
+diathesis, chronic nephritis, or diabetes complicate the tuberculosis
+and bring about a normal pressure or a hypertension. Occasionally the
+period just preceding a hemoptysis or during a hemoptysis may show
+hypertension in a patient whose usual condition is that of hypotension.
+
+"Hypotension has been found by so many observers in early, doubtful or
+suspected cases with or before physical signs of the disease in the
+lungs, and is considered by competent clinicians so useful a
+differential sign between various conditions and tuberculosis, that it
+should be sought for as carefully as it is the custom at present to
+search for pulmonary signs.
+
+"Hypotension when found persistently in individuals or families or
+classes living under certain unhygienic conditions should put us on our
+guard against at least a predisposition to tuberculosis. Most unhygienic
+conditions, overwork, undernourishment and insufficient air, are of
+themselves causes of a diminished resistance, and it seems likely that a
+failure of normal cardiovascular response to exercise or change of
+position may be found to indicate this stage of susceptibility,
+especially to tuberculous infection.
+
+"... Hypotension, when it is present in tuberculosis, increases with an
+extension of the process. Recovery from hypotension accompanies arrest
+or improvement. Return to normal pressure is commonly found in those who
+are cured. Continuation of hypotension seems never to accompany
+improvement. Prognosis can as safely be based on the alteration in the
+blood pressure as on changes in the pulse or temperature...."
+
+There are a few drugs which lower the blood pressure, but, as a rule,
+their effects are more or less transitory. We know of no drug, unless it
+be iodide of potassium, which has the property of causing changes in the
+blood (decrease in viscosity?), which tends to reduce the blood pressure
+when it is excessive. This drug fails us many times.
+
+
+SOME DRUGS WHICH INFLUENCE THE BLOOD PRESSURE
+
+ =Pressure Raisers=
+
+ Adrenalin, when injected directly
+ into a vein or deep into the muscles.
+ The action is transitory.
+
+ Caffeine, preferably in the form
+ of caffeine-sodium-benzoate. A good
+ drug.
+
+ Strychnine, which does not act directly
+ but seemingly through the
+ higher centers.
+
+ Ergot, somewhat uncertain.
+
+ Nicotine, not used therapeutically.
+
+ Camphor, used in sterile olive oil
+ and injected deeply into the muscles.
+
+ Digitalis, when the cardiac tone is
+ low and decompensation is present.
+ Its action is prolonged but slow. Injections
+ of the infundibular portion
+ of the pituitary body. Not in use
+ clinically.
+
+
+ =Pressure Depressors=
+
+ Nitroglycerine and amyl nitrite,
+ action transitory but rapid.
+
+ Sodium nitrite and erythrol tetranitrate.
+ Action somewhat more prolonged.
+
+ Aconite, veratrum viride, chloral,
+ etc. These depress the heart.
+
+ Purgatives, drastic and hydragogue.
+
+ Potassium and sodium iodide may
+ lower blood pressure. When they do,
+ the action is prolonged.
+
+ Diuretin and theocin-sodium-acetate.
+
+
+=Venous Pressure=
+
+Comparatively little work has been done upon the determination of the
+pressure in the veins in man. It is conceivable that this procedure may,
+at times, be of great value. A number of attempts have been made to
+measure the venous pressure by compressing the arm veins and noting on a
+manometer the force necessary to obliterate the vein. As the pressure is
+so slight, water is used instead of mercury, and readings have been
+given in centimeters of water.
+
+[Illustration: Fig. 33.--Apparatus for estimating the venous blood
+pressure in man, devised by Drs. Hooker and Eyster. The small figure is
+the detail of the box B. See explanation in text.]
+
+In the apparatus shown in the figure (Fig. 33), Drs. Hooker and Eyster
+succeeded in making estimations of the venous pressure. The box _B_ is
+held in position by the tapes _A_, so that the vein is visible through
+the rectangular opening in the thin rubber covering the bottom. The box
+is connected with the water manometer _G_, by a rubber tube, from which
+a T-tube enters the rubber bulb _E_. When the bulb _E_ is compressed
+between the plates _D_, by the coarse thumbscrew _C_, air is forced
+into the box _B_, exerting a pressure on the vein lying exposed beneath.
+This pressure is transmitted directly to the manometer =G=, and may be
+read off in centimeters of water on the accompanying scale. The veins of
+the back of the hand are used and there must be no obstruction between
+them and the heart. The rubber-covered box is accurately and lightly
+fitted over a vein and pressure made until it is obliterated. By
+measuring the distance above or below the heart level that the hand was
+when the observation was made, and subtracting or adding these figures
+to the manometer reading, we obtain the venous pressure at the heart
+level.
+
+Eyster has modified this instrument so that it is now much simpler to
+operate. He uses a small glass cup with a flaring edge and a diameter of
+about 2 cm. This is sealed to the skin directly over a vein on the back
+of the hand by means of collodion. The stem of the cup has a rubber tube
+leading to a small hand bulb and to the manometer tube which contains
+colored water. Slight compression of the hand bulb obliterates the vein
+which can be seen through the glass cup. The pressure in centimeters of
+water is then read off. (Fig. 34.) The principle is the same as in the
+earlier instrument, but the application is easier.
+
+[Illustration: Fig. 34.--New venous pressure instrument. (After
+Eyster.)]
+
+Practically Hooker and Eyster found that the normal variation in healthy
+subjects was from 3 to 10 cm. of water. The pressure rose in cases of
+decompensated hearts with dyspnea and venous stasis, and returned to
+normal with improvement in the condition of the patient. It might be
+possible with this instrument to foretell an oncoming decompensation by
+the rise in venous pressure.
+
+The venous pressure may also be estimated roughly by slowly elevating
+the arm and noting the instant at which a particular vein collapses. By
+measuring the height of the vein above the heart some idea may be
+obtained of the pressure within the right auricle.
+
+
+=The Pulse=
+
+There is nothing characteristic about the pulse of a person suffering
+from arteriosclerosis, except it be the difference in the pulse of high
+tension and of low tension. The pulse of high tension has a gradual
+rise, a more or less rounded apex, and the dicrotic wave is slightly
+marked and occurs about half-way down on the descending limb. In
+arteriosclerosis with low tension the radial artery is usually so rigid
+that very little pulse wave can be obtained. The general form of a low
+tension pulse is a sharp upstroke, a pointed summit, and a secondary
+wave on the base line, which corresponds to the dicrotic wave. Such a
+pulse can be easily palpated, and is known as a dicrotic pulse. However,
+such a pulse can occur only when the artery still retains all or a large
+part of its elasticity; hence in arteriosclerotic low tension we would
+never see such a pulse as the typical dicrotic.
+
+
+=The Venous Pulse=
+
+It would carry us too far to discuss fully the character of the venous
+pulse, but a brief summary of the essential features of the normal
+venous pulse is presented. The venous pulse is a term used to express
+the tracing obtained from the internal or external jugular vein at the
+root of the neck. Normally a very characteristic curve is produced,
+which can be readily analyzed into a series of waves corresponding to
+the fluctuations in the cardiac cycle. To understand these waves and
+their values, the accompanying figure is helpful. (Fig. 35.)
+
+[Illustration: Fig. 35.--Semidiagrammatic representation of the events
+in the cardiac cycle: Jug., pulse in the jugular vein; Aur., contraction
+of auricle; V. Pr., intraventricular pressure; Pap. M., contraction of
+the papillary muscles; Car., carotid pulse. Below are given the times of
+occurrence of the heart sounds and of the opening and closing of the
+heart valves. (After Hirschfelder.)]
+
+Bachmann summarizes the normal waves in the venous pulse tracing as
+follows:
+
+"The physiological or so-called venous pulse consists of three positive
+and three negative waves, bearing a more or less definite relation to
+the events of the cardiac cycle, and having their origin in the various
+movements of the chambers and structures of the right heart. The first
+positive wave (_a_) is presystolic in time, and is due to the
+contraction of the auricle, causing a slowing of the venous current and
+producing a centrifugal wave through a sudden arrest of the inflowing
+blood. The second positive wave (_S_) is presystolic in time, and
+originates in the sudden projection of the tricuspid valve into the
+cavity of the auricle during the quick, incipient rise in the
+intraventricular pressure occurring in the protosystolic period. The
+third positive wave (_v_) occurs toward the end of ventricular systole.
+It consists of two lesser waves separated by a shallow notch. The
+factors entering into its formation are the relaxation of the papillary
+muscle at a time when the intraventricular is still higher than the
+intraauricular pressure, resulting in an upward movement of the
+tricuspid leaflets and a return of the auriculoventricular septum to its
+position of rest.
+
+"The first negative wave (between positive wave _a_ and _S_) is due to
+the relaxing auricle. The second negative wave (_Af_) occurs during the
+diastole of the auricle. It is due to the dilatation of its walls, to
+the displacement of the auriculoventricular septum toward the apex
+occurring at the time of ventricular systole, and to the pull of the
+papillary muscles on the tricuspid valve leaflets. The third negative
+wave (_Vf_) appears during ventricular diastole and in the common pause
+of the heart chambers. Its cause is found in the passage of the blood
+from the auricle into the ventricle. It is somewhat modified possibly by
+the continual ascent of the auriculoventricular septum and by a wave of
+stasis due to the accumulation of blood coming from the periphery."
+(Fig. 36.)
+
+[Illustration: Fig. 36.--Simultaneous tracings of the jugular and
+carotid pulses showing normal waves in the venous pulse and relation to
+carotid pulse. (After Bachmann.)]
+
+Hirschfelder has described another wave which he calls the "h" wave,
+which is due to the floating up of the tricuspid valve by the blood in
+the ventricle before the complete filling of the ventricle following the
+auricular systole. (Fig. 37.)
+
+[Illustration: Fig. 37.--Jugular and carotid tracing from a normal
+individual with a well-marked third heart sound showing a large "h" and
+a smaller pre-auricular wave "w." ? indicates a small wave in
+mid-diastole following the "h" wave, occasionally found though perhaps
+an artefact. (After Hirschfelder.)]
+
+
+=The Electrocardiogram=
+
+In the past few years an immense amount of work has been done by
+numerous observers on the changes in the electrical potential of the
+various portions of the heart during contraction. The very elaborate and
+delicate electrocardiograph with the string galvanometer devised by
+Einthoven is used. It has been definitely determined that the impulse to
+cardiac contraction originates in the sinus node, a collection of
+differentiated nerve cells situated at the junction of the superior vena
+cava with the right auricle. From there the impulse travels in certain
+fibers in the interauricular wall, passes through another node, the
+auriculoventricular or Tawara node, situated in the auricular wall just
+above the auriculoventricular ring, thence via the Y-bundle, or bundle
+of His to the ventricles. This sequence is orderly, regular, and
+normally invariable. (Fig. 38.)
+
+[Illustration: Fig. 38.--Right side of the heart showing
+diagrammatically the distribution of the two vagus nerves to different
+parts of the viscus. The impulse to contraction originates at the
+sino-auricular node and passes over the wall of the auricle to Tawara's
+node, and thence over His' bundle across the auriculoventricular septum
+to be distributed throughout the ventricular wall. If the upper,
+sino-auricular, node is damaged, or if its impulses fail to get across
+the wall of the auricle, Tawara's node acts in its place to start off
+the ventricle. If a lesion at the base of the mesial segment of the
+tricuspid valve damages His' bundle, so that Tawara's node is cut off
+from the ventricle, then the ventricle may originate its own impulses to
+contraction. (Hare's Practice of Medicine.)]
+
+The sino-auricular (s-a) node is the most irritable portion of the
+heart, it is endowed with the greatest amount of rhythmicity as well.
+It is under the control of the vagus nerve. Its inherent rate of
+rhythmicity is probably more rapid than the usual numbers of impulses
+per minute, but it is inhibited by the vagus. Paralysis of the vagus
+endings increases the rate of impulse formation and therefore the rate
+of the heart.
+
+The electrocardiogram is a graphic representation on a photographic film
+or sensitive bromide paper of the changes of electrical potential during
+muscular activity. The lines are made by the highly magnified string of
+the galvanometer as it moves across the slit in the photographic
+apparatus in response to the induction currents set up in the heart
+magnified by the special galvanometer.
+
+The record is made in three so-called Leads.
+
+ Lead I
+
+ The electrodes are attached to right arm and left arm.
+
+ Lead II
+
+ The electrodes are attached to right arm and left leg.
+
+ Lead III
+
+ The electrodes are attached to left arm and left leg.
+
+A series of regular figures is normally obtained in which are
+depressions and elevations and regular spacing of these elevations and
+depressions. The waves so-called have been arbitrarily designated _P_,
+_Q_, _R_, _S_, _T_. There is some difference in the three leads. "The
+wave _P_ is positive in _all leads_. _P_ to _R_ interval varies slightly
+in the _three leads_. All the waves of _Lead II_ are greater than those
+of _Leads I_ and _III_. The wave _R_ is positive in _all leads_. _T_ is
+usually positive in _all leads_, but is occasionally negative in Lead
+III. Even in normal individuals there is a considerable range of
+variation in the electrocardiogram which is within the limits of the
+normal." (Hart.) (Fig. 39.)
+
+[Illustration: Fig. 39.--Normal electrocardiogram. (After Hart.)]
+
+The _P_ wave is admitted to be the wave of auricular contraction. _Q_,
+_R_, _S_, is the ventricular complex caused, it is thought, by the
+current passing over the ventricles. _T_ wave is not yet definitely
+settled. It has been thought by some that it represented actual
+ventricular contraction and its height and shape had some meaning in
+heart force. This is denied by others. Hart defines it as "The final
+activity of the ventricle." The _T_ wave is usually increased in size
+during exercise.
+
+The _P-R_ interval is almost the most important feature of the tracing.
+It is the actual conduction time in fractions of a second of the impulse
+from s-a node to the ventricles. Normally this is about 0.2 second or
+slightly less. Much that was hoped for from the electrocardiograph in
+the clinic has not been forthcoming. Its greatest value is in states of
+abnormal conductivity, such as various grades of heart block,
+extrasystoles, whether originating in auricles or in either ventricle,
+abnormalities of rhythm, as flutter and fibrillation. It has, however,
+aided materially in the intelligent interpretation of many phenomena
+heretofore not well understood, and has enormously increased our
+knowledge of the physiology and pathologic physiology of the heart.
+
+It is not possible to enter farther into the subject here. This brief
+discussion must suffice. The reader is referred to works on this subject
+in connection with diseases of the heart.
+
+
+
+
+CHAPTER IV
+
+IMPORTANT CARDIAC IRREGULARITIES ASSOCIATED WITH ARTERIOSCLEROSIS
+
+
+Arteriosclerosis of the aorta, of the coronary arteries, or of both, is
+practically always found in cases dying of various cardiac
+irregularities other than those the result of rheumatic cardiac lesions.
+It is not that arteriosclerosis causes the cardiac lesions (although the
+thickening of the walls of the coronary arteries does interfere
+mechanically with the nutrition of the heart muscle), but the
+arteriosclerosis is a part of the tissue reaction in the arteries to
+some set of causes affecting the whole body. It is true when one boils
+down the question to its last analysis, general arteriosclerosis may
+mechanically so interfere with the blood supply to tissues that the
+tissue is thrown out of function either in the reduction or even loss of
+function. So it may be that occasionally the arteriosclerosis in the
+arteries supplying the heart is really responsible for the cardiac
+irregularity. The past few years have been fruitful ones in increasing
+our knowledge of the various irregularities of the heart. We can do no
+more than sketch briefly some of them in relation to arteriosclerosis.
+
+The chief irregularities are (1) auricular flutter, (2) auricular
+fibrillation, (3) ventricular fibrillation, (4) auricular extrasystole,
+(5) ventricular extrasystole, (6) heart block, partial or complete.
+
+
+=Auricular Flutter=
+
+Auricular flutter is an abnormal rhythm characterized by very rapid, but
+rhythmic auricular contractions usually 250 to 300 per minute. The
+auricular contractions are so rapid that the ventricle can not respond,
+so that an electrocardiagram of a heart in such a state (Fig. 40) shows
+the ventricle beating regularly but at a much slower rate than the
+auricle.
+
+[Illustration: Fig. 40.--(After Hart.)]
+
+The majority of cases exhibiting this peculiar rhythm are over 40 years
+of age. In many cases sclerosis of the coronary arteries as a part of
+general arteriosclerosis has been found. Auricular flutter can be
+suspected when the pulse is regular or not particularly irregular and a
+fluttering, rapid pulsation is seen in the jugular vein on the right
+side. One can only be sure of the condition by making graphic records of
+the heart.
+
+Attacks usually come on suddenly and may disappear as suddenly,
+suggesting paroxysmal tachycardia. The patient feels a commotion in his
+chest, dyspnea, precordial distress, etc. The attack may last for weeks
+or months, in which case the patient may carry on his usual work but be
+conscious of palpitation in his chest. One may safely assume that the
+flutter is a sign of a failing myocardium and sooner or later the heart
+will pass to the graver stage of auricular fibrillation.
+
+
+=Auricular Fibrillation=
+
+In this condition the auricle is widely dilated and over its surface are
+countless twitchings of individual muscles giving to the auricle the
+appearance of a squirming bunch of worms. Such a condition may be
+readily produced in a dog's exposed heart by direct faradization of the
+auricle. It should be seen by every physician in order fully to
+appreciate the passive, dilated sac part which the auricle plays when in
+such a state. There is no auricular wave on the electrocardiogram (Figs.
+41 and 42) only a series of fine tremulous lines, and the ventricles
+beat irregularly with many dropped beats and variations in the size and
+force of individual beats. Extrasystoles are also frequent. The heart is
+absolutely irregular. Such a condition is readily recognizable as the
+state of broken compensation. Graphic records are not essential as in
+auricular flutter to establish the condition. Inspection of the root of
+the neck for jugular pulsations and examination of the pulse with the
+patient's evident dyspneic, cyanotic, edematous condition settles the
+diagnosis.
+
+[Illustration: Fig. 41.--Electrocardiogram showing auricular
+fibrillation in Leads I (upper) and II (middle and lower). (Courtesy of
+Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 42.--Auricular fibrillation. (After Hart.)]
+
+In no case of auricular fibrillation is the heart muscle free from
+extensive fibrous changes. These may be the result of general
+arteriosclerotic changes or may result from toxic changes. It is the
+general consensus of opinion that auricular fibrillation may persist for
+months or even years. Some hold that the state of perpetual irregular
+pulse is associated with auricular fibrillation. If that is true, then
+auricular fibrillation may last for many years. Patients may go about
+their work but always live with the imminent danger of a sudden
+dilatation of the ventricle and symptoms of acute cardiac
+decompensation.
+
+In these cases the blood pressure is of particular interest. It is often
+stated that the blood pressure is lowered as compensation returns and
+digitalis has exhibited its full action. As a matter of fact this
+statement needs some modification. If one takes the highest pressure at
+the strongest beat, which may be only one in a dozen or more, that may
+be true, but that does not represent the action of the much embarrassed
+heart. We know that the circulation is much interfered with, that there
+is hypostatic congestion, that the mass action is slow. The pulse
+pressure is greatly disturbed and the head of pressure which should
+force the blood to the periphery is so little that the circulation
+almost ceases.
+
+A count of the cardiac contractions heard with the stethoscope and a
+count of the pulse shows a great discrepancy in number. This has been
+called the "pulse deficit" (Hart). In order to arrive at the true
+average systolic pressure the following procedure is done. "The apex and
+radial are counted for one minute, at the same time by two observers,
+(if possible) then a blood pressure cuff is applied to the arm, and the
+pressure raised until the radial pulse is completely obliterated; the
+pressure is then lowered 10 mm., and a second radial count is made; this
+count is repeated at intervals of 10 mm. lowered pressure until the
+cuff-pressure is insufficient to cut off any of the radial waves
+(between each estimation the pressure on the arm should be lowered to
+zero). From the figures thus obtained the average systolic blood
+pressure is calculated by multiplying the number of radial beats by the
+pressures under which they came through, adding together these products
+and dividing their sum by the number of apex-beats per minute, the
+resulting figure is what we have called the 'average systolic blood
+pressure.'" (Fig. 43.)
+
+[Illustration: Fig. 43.--The shaded area represents the pulse deficit;
+the upper edge is the apex rate, the lower edge the radial rate. The
+broken line indicates the "average systolic blood pressure." (Compare
+these values with the figures at the bottom of the chart, which show the
+systolic blood pressure determined by the usual method.) (After Hart.)]
+
+For example: "B. S., April 29, 1910, Apex 131; radial, 101; deficit, 30.
+
+ BRACHIAL PRESSURE RADIAL COUNT
+ 100 mm. Hg. 0
+ 90 mm. 13 13 x 90 = 1170
+ 80 mm. 47 - 13 = 34 x 80 = 2720
+ 70 mm. 75 - 47 = 28 x 70 = 1960
+ 60 mm. 82 - 75 = 7 x 60 = 420
+ 50 mm. 101 - 82 = 19 x 50 = 950
+ ----
+ Apex = 131) 7220
+ ----
+ Average systolic blood-pressure 55 plus
+
+B. S., May 11, 1910, Apex 79; radial, 72; deficit 7.
+
+ BRACHIAL PRESSURE RADIAL COUNT
+ 120 mm. Hg. 0
+ 110 mm. 44 44 x 110 = 4840
+ 100 mm. 64 - 44 = 20 x 100 = 2000
+ 90 mm. 72 - 64 = 8 x 90 = 720
+ ----
+ Apex = 79) 7560
+ ----
+ Average systolic blood-pressure 95 plus"
+
+The diastolic pressure in these cases can not be determined except
+approximately. This may be done by using an instrument with a dial and
+noting the pressure where the oscillations of the dial hand show the
+maximum excursion. The diastolic pressure is not at all important under
+such conditions of acute cardiac breakdown. It would make no difference
+in treatment whether the case was one of pure cardiac disease or one
+of the hypertension groups. After the heart has rallied and the
+circulation is reestablished, then a careful determination of the
+diastolic pressure can be made and the prognosis will rest on what is
+found at the compensated stage.
+
+
+=Ventricular Fibrillation=
+
+Ventricular fibrillation as its name implies, is fibrillation of the
+ventricle analogous to that of the auricle, but the condition is rarely
+observed as it is incompatible with life. It has been shown that hearts
+at the time of death at times enter a state of fibrillation of the
+ventricles and that cases of sudden death may be due to this condition.
+Recently G. Canby Robinson[12] has seen and made electrocardiograms of a
+case of ventricular fibrillation. (Fig. 44.) The case was that of a
+woman forty-five years old, "who had a series of attacks of prolonged
+cardiac syncope, closely resembling Stokes-Adams syndrome, from which
+she recovered." During an attack of unconsciousness in which there was
+no apex beat for about four minutes, the electrocardiogram was taken.
+Following this the tracings showed an almost regular heart beating at
+the rate of 85 to 100 per minute. The patient had three convulsions and
+died with edema of lungs about 30 hours after the attack of ventricular
+fibrillation.
+
+ [12] Robinson, G. C., and Bredeck, J. F.: Arch. Int. Med., 1917, xx,
+ 725.
+
+[Illustration: Fig. 44.--Upper curve. Record obtained during period of
+cardiac syncopy at 2:48 p.m., Lead II. Lower curve from dog. Ventricular
+fibrillation observed in the exposed heart. Lead from right foreleg and
+left hind leg. (Courtesy of Dr. G. C. Robinson.)]
+
+Autopsy revealed chronic fibrous endocarditis of aortic and mitral
+valves, arteriosclerosis, bilateral carcinoma of the ovaries, and signs
+of general chronic passive congestion.
+
+It is possible that the syncopal attacks in this case were the result of
+sclerosis of the vessels supplying the heart muscle although careful
+microscopical examination did not throw much light on the ultimate
+cause.
+
+
+=Extrasystole=
+
+Whenever there is a dropped beat or an intermittent pulse one may be
+sure that it is the result of an extrasystole. Such extrasystoles are
+produced in the ventricle at some point other than the regular path of
+conduction of impulses. The extrasystole may have its origin in either
+the auricle or the ventricle. If there is auricular extrasystole it can
+not usually be recognized except by graphic methods. (Fig. 45.) The
+ventricular extrasystole on the contrary is commonly seen and readily
+recognized. Most of those seen in the clinic have their origin in some
+part of the ventricular wall. Their two characteristics are that they
+occur too early and that they are followed by a pause longer than the
+normal diastolic pause. (Fig. 46.)
+
+[Illustration: Fig. 45.--Electrocardiogram showing auricular
+extrasystoles (P). (Courtesy of Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 46.--Electrocardiogram showing ventricular
+extrasystole. Heart rate 56-60 beats per minute. Note that diastolic
+pause in which extrasystole occurs is practically equal to two normal
+diastolic pauses. (Courtesy of Dr. G. C. Robinson.)]
+
+When one listens over the chest to a heart when extrasystoles are
+occurring, one suddenly hears a weak beat which has taken place rather
+too early after the previous systole to be strong enough to effect the
+opening of the aortic valves. Consequently there is no pulse, the blood
+does not move, and that beat is lost to the circulation. Moreover, when
+the next regular stimulus comes from the s-a node it finds the ventricle
+in a refractory condition, having just ceased a contraction, and it is
+not until the next sinus impulse that the ventricle responds normally.
+(Fig. 46.)
+
+Patients who have occasional extrasystoles will say that all of a sudden
+the heart turns upside down in the chest. Sometimes there is slight
+sharp twinge of pain. Patients are at times quite alarmed about their
+condition. Provided there is no evidence of gross myocardial lesion, the
+extrasystole itself is of no great significance.
+
+While many cases showing pathologic causes for extrasystoles have more
+or less marked arteriosclerosis, there are other states in which no
+arteriosclerosis is found where the extrasystole is present.
+
+
+=Heart Block=
+
+As heart block occurs frequently in cases characterized by extensive
+arteriosclerosis, a brief discussion of the essential features will be
+given. It is, however, probable that arteriosclerosis is not the cause
+of any of the cases of heart block directly, but it is only a result of
+the same etiological conditions which produce the lesion or lesions
+which result in heart block. We may define heart block as the condition
+in which the auricles and ventricles beat independently of each other.
+There may be delayed conduction (Fig. 47), partial (Fig. 48), or
+complete heart block (Fig. 49). In the former there are ventricular
+silences, during which the auricles beat two, three, four, five, even up
+to nine times, with only one ventricular contraction. It is believed by
+most physiologists that the essential factor in the production of heart
+block is an interference in the conduction of impulses from the
+auricles to the ventricles through the band of tissue known as the
+auriculoventricular bundle.
+
+[Illustration: Fig. 47.--Electrocardiogram showing delayed conduction
+(lengthening of P-R interval). These P-R intervals are quite regular.
+When irregular there is apt to be extrasystole of ventricle or
+occasional blocking of impulse going to ventricle. (Courtesy of Dr. G.
+C. Robinson.)]
+
+[Illustration: Fig. 48.--Electrocardiogram showing partial heart-block
+in the three leads. Note the variability of P-R interval calculated in
+seconds in Lead II. (Courtesy of Dr. G. C. Robinson.)]
+
+[Illustration: Fig. 49.--Complete heart block. (Courtesy of Dr. G. C.
+Robinson.)]
+
+The bundle of muscles described by His in 1905, connecting the auricles
+and ventricles, has been definitely shown to be the path through which
+impulses having their origin in the orifices of the great veins pass to
+the ventricles. The situation and size of this bundle has been thus
+described in man by Retzer:
+
+"When viewed from the left side, the bundle lies just above the muscular
+septum of the ventricles and below the membranous septum. In some hearts
+the muscular septum is so well developed that it envelops the bundle. It
+is then difficult to find, but occasionally it can be seen directly by
+means of transmitted light. From the left side the bundle can be
+followed no farther posteriorly than the right fibrous trigone, for here
+the connective tissue becomes so dense that it is difficult to dissect
+it away. The impression is, therefore, received that this mass of
+connective tissue forms the insertion of the bundle. The bundle may be
+followed anteriorly until it becomes intimately mixed with the
+musculature of the ventricles.
+
+"When viewed from the right side of the heart, the bundle can not be
+seen, because it is covered by the mesial leaflet of the tricuspid
+valve, whose line of attachment passes obliquely over the membranous
+septum. Then, if the endocardium is removed from the posterior part of
+the septum of the auricle up to the membranous septum, the posterior
+part of the auriculoventricular bundle will be exposed. If, in addition,
+the membranous septum be removed, the bundle may be traced from the
+point to which it could be followed when viewed from the left side as it
+passes posteriorly over the muscular septum. In the region of the
+auriculoventricular junction it loses its compactness, the fibers
+divide, and the bundle seems to fork. One branch passes into the
+superficial part of the valve musculature which descends from the
+auricles, and the other branch passes directly into the musculature of
+the auricle.
+
+"Briefly, the auriculoventricular bundle runs posteriorly in the septum
+of the ventricles about 10 mm. below the posterior leaflet of the aortic
+semilunar valves; with a gentle curve it passes posteriorly just over
+the upper edge of the muscular septum and sends its fibers into the
+musculature of the right auricle and of the auricular valves. In the
+heart of the adult the bundle is 18 mm. long, 2.5 mm. wide, and 1.5 mm.
+thick." (Erlanger.)
+
+All normal impulses have their origin in the sino-auricular node at the
+junction of the superior vena cava with the right auricle (Fig. 50).
+From there the impulse travels in the wall of the auricle in the
+interauricular septum to the node of Tawara or A-V node (Fig. 51),
+thence through the bundle of His to be distributed to the fibers of the
+right and left ventricles. This sequence is orderly and perfectly
+regular.
+
+[Illustration: Fig. 50.--Showing alternating periods of sinus rhythm and
+auriculoventricular rhythm. (After Eyster and Evans.)]
+
+[Illustration: Fig. 51.--Period of auriculoventricular or "nodal" rhythm
+following exercise in sitting posture. (After Eyster and Evans.)]
+
+It has also been shown that the independent auricular and ventricular
+rates vary somewhat, that of the auricle being in general faster than
+that of the ventricle. A strip of mammalian ventricle placed outside of
+the body in proper surroundings will begin to beat automatically at the
+rate of about 40 beats a minute. Experimentally various grades of heart
+block have been produced in the dog's heart by more or less compression
+of the bundle at the A-V ring. The block may be partial, when two to
+nine auricular beats occur to every one of the ventricle, up to
+absolute complete block when the auricles and ventricles beat
+independently of one another.
+
+In any stage of partial block, pressure on the vagus nerve in the neck
+produces certain specific changes. (Fig. 52.) Robinson and Draper[13]
+have found qualitative differences in the two vagi. The right vagus
+sends most of its fibers to the s-a node (Fig. 53) and has a more
+evident influence on the rate and force of the cardiac contractions. The
+majority of fibers from the left vagus are distributed to the A-V node
+so that its most evident action is upon the conductivity of the impulse.
+Pressure then on the right vagus will have a tendency to slow the whole
+heart. Pressure on the left vagus will have a tendency to prolong the
+P-R interval until even complete block occurs. Even when the heart block
+is complete, stimulation of the accelerator nerve, as a rule, increases
+the rate of both auricles and ventricles.
+
+[Illustration: Fig. 52.--Influence of mechanical pressure on the right
+vagus nerve. (After Eyster and Evans.)]
+
+[Illustration: Fig. 53.--Schematic distribution of right and left vagus.
+(After Hart.)]
+
+ [13] Jour. Exper. Med., 1911, xiv, 217.
+
+If the block is functional, depending upon some temporary
+overstimulation of the vagus nerve, atropin, which paralyzes the endings
+of the vagus, will naturally lift the block. If the block is due to some
+actual lesion of the bundle of His, such as fibrosis, gumma, or other
+lesion, then atropin will have no influence to terminate the block. In
+this manner we are able to distinguish between functional and organic
+heart block.
+
+
+
+
+CHAPTER V
+
+BLOOD PRESSURE IN ITS CLINICAL APPLICATIONS
+
+
+It is well to bear constantly in mind the point made over and over in
+this work, that blood pressure is only one of many methods of acquiring
+information. He who worships his sphygmomanometer as a thing apart and
+infallible will sooner or later come to grief. Judgment must be used in
+interpreting changes in blood pressure just as judgment is essential in
+properly evaluating any instrumental help in diagnosis. One must not
+forget the personal equation which enters into even accurate
+instrumental recording in medicine and surgery.
+
+In this chapter there will be no attempt to quote largely from what
+others have said or thought. Every one has his own opinion as to the
+value of certain methods after he has worked with them for a long time.
+The ideas here expressed, except in cases where no opportunity has
+offered to make personal studies, are those gathered from personal
+experience.
+
+
+=Blood Pressure in Surgery=
+
+Careful estimation of the blood pressure in surgical cases has, at
+times, great value. In all surgical diseases the most important fact to
+know is not the systolic pressure, but the pulse pressure. If the pulse
+pressure keeps within the range of normal, does not drop much below 30
+mm. in an adult, then so far as we can tell the circulation is being
+carried on. When the systolic pressure is gradually falling and the
+diastolic remains the same, the circulation is failing and unless the
+pulse pressure can be established again the patient will die. Again we
+see the value of the pulse pressure.
+
+All prolonged febrile diseases tend to produce a lowering of the blood
+pressure picture. The diastolic does not fall to the same extent as the
+systolic so that there is a pulse pressure smaller than normal. This is
+to be expected from what we know of the general depression of the
+circulation in fevers. The blood pressure reading is only a graphic
+record of what we have long known, and enables us from day to day
+accurately to measure the general circulation.
+
+
+=Head Injuries=
+
+It was claimed that in fracture of the skull or in concussion much could
+be gained by frequent estimations of the blood pressure. This seemed
+probable in the light of experiments on compressing the brains of dogs
+by the use of bags inserted through trephine openings (Cushing). In the
+clinic, however, it has not been found of any material value. It has a
+value in differentiating a simple fracture, let us say, from a case of
+uremia which is picked up on the street with a bump on the head. There
+the high pressure usually found would at once direct attention to the
+kidneys and the newer methods of blood examination would at once settle
+the question. Naturally uremics may also have skull fracture. There the
+diagnosis would be complicated. A decompression done at once would be
+indicated. If the skull fracture happened in a uremic, the decompression
+would probably do no harm. In fact, there are some who advise
+decompression for uremia.
+
+
+=Shock and Hemorrhage=
+
+In shock the blood pressure picture is low but the pulse pressure drops
+to abnormally low figures. It seems to me that the blood pressure
+instrument has its greatest value in surgery in the warning it gives to
+the operating surgeon in cases of impending shock.
+
+It is well known that the first effect of ether, the commonly used
+anesthetic, is to raise the blood pressure and quicken the pulse rate.
+The whole blood pressure picture is at first elevated (Fig. 54). Soon
+the whole pressure falls slightly but continues at a higher level than
+normal. The diastolic pressure drops back nearly to normal and the
+increased pulse pressure is due almost entirely to the slight rise in
+the systolic pressure. Now the whole duty of the anesthetist is to
+administer the ether so that this ratio of systolic and diastolic is
+maintained throughout the operation. Warning comes to him of impending
+shock before it comes to any one in the neighborhood (Fig. 55). Any
+sudden change in the pressure is a signal for increased watchfulness.
+Should the pressure all at once drop he can immediately notify the
+surgeon and institute measures to resuscitate the patient.
+
+[Illustration: Fig. 54.--Blood pressure record from a normal reaction to
+ether. Note that the systolic and diastolic rise and fall together. At
+the end of the anesthetization the pulse pressure is practically the
+same as at the beginning. Compare this with the record in Fig. 55, where
+the operation had to be discontinued on account of the onset of shock.]
+
+[Illustration: Fig. 55.--Beginning of operative shock. Chart showing the
+method of recording blood pressure during operation.
+
+Note that the pulse and respiration show no remarkable changes, but the
+blood pressure steadily fell, the systolic more than the diastolic so
+that the pulse pressure was gradually reaching the danger point. Further
+work on this case was stopped following the warning given by the blood
+pressure. The patient was returned to the ward and a week later
+anesthesia was again given, the operation was completed, and the patient
+had a satisfactory convalescence.]
+
+A method which is widely used is as follows: The anesthetist wraps the
+cuff of one of the dial instruments around the patient's arm, and
+arranges the dial so that it can easily be seen by him at all times.
+This does not in any way interfere with the work of the surgeon. Over
+the brachial artery below the cuff is the bell of a binaural stethoscope
+held in place by the strap attachment now on the market. The tubes of
+the stethoscope are long enough to reach conveniently to the ear pieces.
+A watch is pinned to the sheet of the table. He has a chart, as
+illustrated (Fig. 56) on a board and makes a dot in every space for five
+minute intervals. By joining the lines a curve is obtained which tells
+at a glance what the circulation is doing. I feel sure that more
+attention and care exercised on the part of the anesthetist would be the
+means of conserving many lives lost from shock following operation.
+
+[Illustration: Fig. 56.--Showing method of using blood pressure
+instrument during operation without interfering with the operator or
+assistants. Sheet thrown back to show cuff on arm of patient.
+Anesthetist has chart on table beside him, dial pinned to pad in full
+view, bulb near hand. Extra tubing must be put on the blood pressure
+instrument.]
+
+A sudden drop in the pressure picture may mean a large hemorrhage. The
+gradual return of the pressure picture means that the vasomotor
+mechanism has acted to keep up the pulse pressure. Should the diastolic
+pressure continually fall, it may mean that the hemorrhage is still
+taking place (Wiggers).
+
+
+=Blood Pressure in Obstetrics=
+
+One might affirm almost without fear of contradiction that the constant
+determination of blood pressure during pregnancy is more important than
+the examination of the urine. Within recent years a number of observers
+having access to a large material, have given the results of their
+findings. There is a striking unanimity of opinion, although now and
+then a difference in minor details.
+
+The blood pressure should be taken frequently during pregnancy. The
+usual and highly essential precautions in taking pressure in general
+apply most particularly in these cases. Towards the end of pregnancy the
+pressure should if possible be taken daily and oftener if necessary.
+
+Pressure in women is usually below 120 mm. Many patients have a
+temporary rise in blood pressure during pregnancy, due oftenest to
+constipation, without developing other symptoms. This is common to all
+conditions and has no significance. Some think that an abnormally low
+pressure, that is, a systolic below 90 mm., suggests that the patient is
+likely to react unduly to the strain of labor. This is denied by others.
+Among 1000 cases (Irving) the pressure was below 90 in only one case. A
+gradually rising pressure precedes albuminuria, as a rule. If there is
+albumin without change in pressure the albumin may usually be
+disregarded. Some think that a pressure over 130 mm. systolic should be
+carefully watched. The danger limit is set by some at 150 mm. If the
+blood pressure from the very first is high, it may mean only that that
+was the patient's normal pressure. This calls for increased
+watchfulness. It is held by some that high blood pressure favors
+hemorrhage and probably explains the hemorrhagic lesions in the placenta
+and some viscera in eclampsia and albuminuria.
+
+All are agreed that the most significant change is the gradual but sure
+rise from a low pressure. When this is combined with albuminuria the
+danger of toxemia is imminent. The high blood pressure in those under
+thirty years of age seems to be a more certain sign of approaching
+toxemia than the same pressure in those older. The pressure falls within
+a few days to its normal after delivery in the toxic cases.
+
+Although the emesis gravidarum is held to be a sign of a toxemia of some
+unknown nature, the blood pressure is never raised even in the
+pernicious form.
+
+
+=Infectious Diseases=
+
+In all infectious diseases the blood pressure tends to be lower than
+normal. During chills the systolic may rise to great height due to the
+violent muscular contractions.
+
+We found the blood pressure of great value in giving information
+concerning the circulation. Again we repeat that it is not the systolic
+alone or the diastolic alone but the pulse pressure which we wish to
+keep informed about. In pneumonia we have tried out Gibson's law only to
+discard it. This so-called law is that in pneumonia the systolic
+pressure in millimeters should remain above the figure for the pulse
+rate. When the figure in mm. of pressure is equalled by or exceeded by
+the pulse rate the prognosis is grave.
+
+In typhoid fever we have made many estimations at various stages of the
+disease. We can only say that the pressure picture tends to fall during
+the course. The systolic falls more than the diastolic so that it is not
+uncommon to see pulse pressures of 20 mm. at the beginning of
+convalescence in spite of the high caloric feeding practiced. At the
+time of perforation the systolic pressure may be raised. This is only
+the reflex from the initial pain. Soon the pressure falls and if
+peritonitis sets in, the pressure is exceedingly low and the pulse
+pressure gradually falls until the circulation can no longer be carried
+on. In large hemorrhage the pressure suddenly falls. If only one
+hemorrhage has occurred a gradual rise takes place, but the general
+pressure picture remains at a lower level for days, gradually returning
+where it was before the hemorrhage.
+
+In beginning failure of the circulation we found elevation of the foot
+of the bed about nine inches to be of such value that we felt there must
+be some increase in blood pressure. Numerous readings were made covering
+a period of several months. Although we felt certain that the
+circulation was improved, we rarely needed cardiac stimulation, we never
+could prove any increase of blood pressure with the sphygmomanometer.
+
+In all infectious diseases there is no help offered by blood pressure
+estimations in diagnosis. The sole and important use is that of keeping
+track of the circulation.
+
+
+=Valvular Heart Disease=
+
+No rules can be laid down for blood pressure in valvular heart disease.
+Aortic stenosis, the rarest of the valvular lesions, is practically
+always accompanied by high pressure picture. Mitral stenosis on the
+contrary usually shows a low pressure picture. Mitral insufficiency may
+show an exceedingly low picture or an exceedingly high picture. Aortic
+insufficiency also may be accompanied by a high systolic or by a normal
+systolic pressure. It depends on the etiology. Practically all the
+rheumatic cases have low pressure, the syphilitic cases have a high
+pressure. It is characteristic of all cases of aortic insufficiency that
+the diastolic pressure is low, even as low as 30 mm. The pulse pressure
+is invariably high. Usually there is no difficulty in determining the
+diastolic pressure. The intense third tone suddenly becomes dull at the
+point of diastolic pressure and frequently the dull sound can be
+distinctly heard over the artery down to the zero of the scale. If
+difficulty is found in reading the diastolic as the pressure is reduced,
+the estimation may be reversed and the pressure gradually increased from
+zero to the point where the dull tone suddenly becomes loud and clear.
+These points always coincide.
+
+
+=Kidney Diseases=
+
+This has already been discussed somewhat fully in Chapter III and will
+receive more consideration later. It might be remarked in passing that
+in a case of seeming coma where albumin is found in the urine but where
+the blood pressure is low or normal, I have found at autopsy in several
+cases pyonephrosis and not chronic nephritis. The blood pressure may be
+useful in differentiating uremic coma from the coma of pyonephrosis.
+Also in the cases of coma with anasarca, either the acute, subacute or
+chronic form the blood pressure is not raised as a rule. Other diseases
+of the kidney, as tuberculosis, cancer, infection with pyogenic
+organisms, are not accompanied with any notable changes in blood
+pressure.
+
+
+=Other Diseases, Liver, Spleen, Abdomen, etc.=
+
+Blood pressure is only of value in the above diseases in affording
+information concerning the state of the circulation. There is nothing
+characteristic about the pressure in any of these diseases.
+
+
+
+
+CHAPTER VI
+
+ETIOLOGY
+
+
+The causes of arteriosclerosis are many and varied. No two persons have
+the same resisting power toward poisons that circulate in the blood.
+Some go through life exposed to all the infectious diseases without ever
+becoming infected, while others fall easy victims to every disease that
+comes, no matter how careful they may be, and it is quite the same in
+regard to the resistance of the arterial tissues. If the tubing is of
+first class quality and the individual does not place too much strain on
+it, he may live to the biblical three-score years and ten, and possess
+arteries which have undergone such slight changes that they are not
+palpable. Such a person is, however, the exception. On the other hand,
+if the tissue is of poor quality, even the ordinary wear and tear of
+life causes early changes in the vessels, and a person of forty may have
+hard arteries.
+
+We have described in a previous chapter the changes which normally occur
+in the arteries as age advances. An artery that is normal for a man of
+fifty years would be distinctly abnormal for a boy of fifteen.
+
+Two broad divisions of arteriosclerosis may be made: (1) congenital, or
+the result of inherited tendency; (2) acquired.
+
+
+=Congenital Form=
+
+When Dr. O. W. Holmes was asked how to live to the age of seventy, he
+replied that a man should begin to pick his ancestors one hundred years
+before he was born. Our parents determine the character of the tissues
+with which we start in life, and this determines our general resistance.
+We might properly speak of congenital arteriosclerosis where the
+affected individual had poor arterial tissue with which to begin life,
+for that, in a sense, is a congenital defect, and arterial tissue that
+is poor in quality is prone to disease.
+
+The author is more and more impressed with the part that heredity plays
+in the determination of arterial degeneration. Especially does syphilis
+in the parents or grandparents leave its stigma in the succeeding
+generations in the shape of poor arterial tissue which is prone to early
+degeneration. Recently W. W. Graves has called attention to a
+malformation of the vertebral border of the scapula which consists in a
+concavity instead of the normal convexity of the bone. To this
+malformation he has given the name, scaphoid scapula. He considers this
+to be but one manifestation of a general lack of development in the
+individual. He speaks of this maldevelopment as a blight and considers
+that syphilis in the ancestors is responsible for the condition in the
+offspring. He finds that even in children, the subjects of the scaphoid
+scapula, the arteries are very definitely thickened. While confirmation
+of his observations is lacking, there is no doubt that we must lay the
+blame for much of the arteriosclerosis in our patients to the poor
+quality of arterial tissue transmitted by ancestors who have acquired
+some constitutional disease. It may have been syphilis, it may have been
+the degeneration produced by alcohol or other drug. We can not ignore
+the part which heredity plays. The various factors to be considered in
+the production of the acquired form of arteriosclerosis appear to me to
+be but contributory factors to a very great extent, the essential and
+fundamental factor being the quality of arterial tissue with which the
+individual is endowed.
+
+Arteriosclerosis may occur in infants. Cases have been reported of
+calcification of the arteries in infants and children. The
+arteriosclerosis may occur without nephritis or rise of blood pressure.
+Cerebral hemorrhage in a child of two years has been seen. Heredity in
+these cases plays a most important role. In many of the reported cases
+there was no question of congenital syphilis. Aneurysms, single or
+multiple, have been found in the arteries of children, and even the
+pulmonary artery may show sclerotic changes.
+
+
+=Acquired Form=
+
+As a rule the cases usually seen belong in this group because it seems
+as if a connection could be established almost always between one or
+more of the etiologic factors to be described and the disease. While
+this apparently is the case, we must never lose sight of the part which
+the quality of the tissue plays. When we leave this out of our
+calculations we undoubtedly make many false deductions. When two men of
+the same age who have been exposed to the same conditions as far as we
+can learn, are found to have quite different arteries, the one normal,
+the other thickened, we must postulate congenitally poor tissue on the
+part of the latter. Such tissue readily becomes diseased following
+conditions which would very likely have produced no noticeable effect on
+perfectly normal, healthy tissue.
+
+
+=Hypertension=
+
+Hypertension must still be reckoned with in the etiology of
+arteriosclerosis although the role that it was thought to play does not
+seem so important. Changes of blood pressure alone are not considered by
+many to be sufficient for the production of arteriosclerosis. This may
+play some part, but there are many other factors mostly unknown which
+determine in any case the production of arterial lesions.
+
+With every systole of the heart, blood is forced out into the arterial
+system against a certain amount of resistance represented by the
+tonicity of the capillary area, and the amount of cohesion between the
+viscous blood and the walls of arterioles. When a dilatation of the
+capillaries over any large area takes place, the blood pressure falls,
+provided there is no compensatory contraction in other areas to make up
+for the decreased resistance in the dilated vessels. The viscosity of
+the blood, as such, probably has very little effect on the resistance to
+the flow. With the systole of the heart there is a sudden dilatation of
+the arch of the aorta, and a wave of expansion follows, which is
+transmitted to the periphery and is lost only in the capillaries.
+
+The blood pressure is constantly changing. Physiologically there are
+relatively wide variations in the pressure in a perfectly normal
+individual. There are some persons who have hypotension, a blood
+pressure much below the normal. Such persons have usually small hearts,
+small aortas, and they seem to have but little resistance to disease.
+Many diseases, especially the prolonged fevers, diminish markedly the
+blood pressure. Whether the hypertension is the cause of the structural
+changes that are found in the walls of the vessels, or is the result of
+the diminished area of the arterial tree through which the same amount
+of blood has to be driven as before the vessel walls became narrowed, is
+still disputed. As has been stated, experimental evidence would tend to
+place the initial blame upon the poisons circulating in the blood, which
+first damage the vessel walls. The subsequent changes then produce
+thickening and inelasticity. Some think (Allbutt) that the hypertension
+is primary. There are cases seen clinically that lend support to this
+view and there is experimental evidence also (v. Chap. II). Not
+infrequently individuals in middle life begin to show increase of
+arterial blood pressure without discoverable cause. In such case it may
+be that there is slowly progressing chronic nephritis. The urine if
+examined only superficially in single specimens may not reveal any
+abnormalities. Careful functional examination by means of the newer
+tests may reveal functional deficiency. It must not be supposed that
+all cases of increasing hypertension are cases of chronic nephritis. The
+opinion has already been expressed (Chap. III) concerning this point.
+Experience has convinced me that the opinion expressed in former
+editions is not altogether correct.
+
+
+=Age=
+
+No age is exempt from the lesions of arteriosclerosis if we consider the
+two groups. However, the disease is seen for the most part in persons
+past middle life. The relative frequency with which it is found in the
+different decades depends on so many factors that it is of no value to
+tabulate them. As has been stated, arteriosclerosis of all types is an
+involution process that advances with age. Longevity is a question of
+the integrity of the arterial tissue, and no one can tell what sort of
+"vital rubber" (Osler) any one of us has. However, many with poor tubing
+may make such use of it that it will outlast good tubing that is badly
+treated. Unfortunately we have no way of telling early enough with just
+what sort of arterial tissue we are starting life.
+
+
+=Sex=
+
+There is no doubt that men are far more prone to arterial disease than
+women are; all statistics are in accord on this point. This is explained
+by the greater exposure of men to those conditions of life which tend to
+produce circulatory strain, and so to produce arteriosclerosis, or vice
+versa. Arteriosclerosis in women is not often seen until after the
+fiftieth year. Cases of the most extreme grade of pipe stem arteries
+are, however, seen in old women, and calcified arteries are not hard to
+find among the inmates of an old woman's home.
+
+
+=Race=
+
+Some of the most beautiful examples of arteriosclerosis in this country
+are seen in the negro. Not only is this disease more frequent in the
+black race, but the age of onset is much earlier than in the Caucasian.
+The accidents of arteriosclerosis, viz., aneurysm, cerebral hemorrhage,
+etc., are more common among the negro males. The etiologic factors that
+are most often found in the history are the prevalence of syphilis and
+hard physical labor.
+
+
+=Occupation=
+
+Certain occupations have a distinct causal relationship to
+arteriosclerosis; among such are particularly those entailing prolonged
+muscular exercise, especially if much lifting is necessary. Every one is
+familiar with the phenomena accompanying the exertion of lifting. The
+breath is drawn in, the glottis is closed, and the muscles of the chest
+wall are held rigidly while the exertion lasts. This causes a great
+increase in blood pressure, and constant repetition of this will produce
+permanent high tension. In hospitals, the stevedores as a class have
+marked arteriosclerosis, and, almost without exception, they are
+comparatively young men. Occupations that are accompanied with prolonged
+mental strain, such as now occur to the heads of large manufacturing and
+financial institutions, also predispose to early arterial changes.
+Psychic activity, especially when it is accompanied by worry, is a
+potent factor in the production of the increased blood pressure which is
+the chief factor in producing arterial disease. It has been suggested
+that sexual continence in high-strung men produces changes in the
+nervous system which can conceivably lead to the production of high
+tension and further to arteriosclerosis. This, however, I can not think
+has any foundation in fact except in so far as such men are prone to
+live at high speed and wear themselves out sooner than the normal
+person. The sexual continence _per se_ is not harmful. There are,
+however, men who seem not to be harmed by the constant wear and tear of
+our modern life. These are the exceptions.
+
+Workers in factories where paint is made and the ingredients
+hand-mixed, are prone to develop arteriosclerosis early in life. It has
+been found that the laborers most apt to be victims of lead intoxication
+are those who are careless in their habits of cleanliness, particularly
+in regard to the fingernails. The continuous absorption of lead into the
+system, brings about a condition of hypertension that has its inevitable
+results.
+
+The fact is that any occupation which entails either the absorption of
+toxic substances, or prolonged muscular labor, will hasten markedly the
+onset of arterial disease.
+
+
+=Food Poisons=
+
+The opinion that arteriosclerosis is due in large part to poisoning by
+end products or by-products of protein digestion is now receiving much
+support. Experiments on dogs and rabbits have lent some confirmation to
+chemical observations. It has been shown that dogs fed for a long time
+on putrefied meat developed inflammation and degeneration of the
+adventitia and media, with hyperplasia and calcification of the intima
+of many arteries. In the pulmonary and carotid arteries, in the vena
+cavas and myocardium, there were extensive necroses and hyaline
+degeneration. Moreover, injections of sodium urate and ergot caused
+necroses in the muscularis and elastica of the aorta, pulmonary artery,
+vena cavas inferior and heart muscle, but there was no calcification.
+Guinea pigs which were fed indol in small doses by the mouth over a long
+period showed atheromatous degeneration of the aorta.
+
+
+=Infectious Diseases=
+
+As more study has been given to the arteries in persons who have died of
+the acute infectious diseases, more has come to light concerning the
+effects of the toxins of these diseases on the vessel walls. In the
+arteries of children who have died of measles, scarlet fever,
+diphtheria, cerebrospinal meningitis, etc., degenerative changes in the
+arteries occur, modified only by the length of time that the toxins have
+acted.
+
+Thayer has shown that the arteries of those who have passed through an
+attack of moderately severe or severe typhoid fever are as a rule more
+readily palpable than are the vessels of persons of corresponding years
+who have never had the disease. Clinically the typhoid toxin appears to
+cause the early production of arteriosclerosis. The changes in the
+arteries occur for the most part, and always earlier, in the peripheral
+arteries, and the media is chiefly affected. Minute yellowish patches
+are found on the aorta, carotids, and coronaries. In persons who have
+passed through an attack of one of the fevers, and have later died from
+some other cause, regenerative changes are sometimes found to have taken
+place in the arteries, consisting of an ingrowth of elastic fibers from
+the intact adventitia to the diseased media.
+
+That there are some other factors than the infectious disease which are
+concerned in the production of arterial changes seems evident from a
+study[14] made recently among a group of almshouse inmates ranging in
+age from 38 to 90 years. The study included 500 persons of both sexes.
+Careful histories were taken to determine the presence of antecedent
+infectious disease. The radial artery was palpated to determine the
+presence of sclerosis. Among the cases giving a history of one
+infectious disease the following table gives the results:
+
+ -------------------------------------------------------------
+ DISEASE NO. + ++ +++ POSITIVE NEGATIVE
+ -------------------------------------------------------------
+ Measles 47 10 6 12 28 19
+ Infectious arthritis 38 9 6 4 19 19
+ Pneumonia 30 5 8 5 18 12
+ Typhoid 27 6 8 3 17 10
+ Scarlet fever 10 0 0 4 4 6
+ Smallpox 14 1 4 0 5 9
+ Miscellaneous 12 2 5 2 9 3
+ -------------------------------------------------------------
+ 178 33 37 30 100 78
+ -------------------------------------------------------------
+
+ [14] Warfield, L. M.: Jour. Lab. and Clin. Med., November, 1917.
+
+A summary of the cases showed: 252 cases without sclerosis; 248 with
+sclerosis; 147 cases with infections but no sclerosis; 180 cases with
+infections and sclerosis.
+
+This study failed to throw any positive light on the question.
+Infectious diseases undoubtedly play a certain role, particularly those
+continuing a long time and certain particular infectious diseases, as
+measles.
+
+
+=Syphilis=
+
+Syphilis is one of the most important of the etiologic factors in the
+production of arteriosclerosis. It has been shown that in 85 per cent of
+cases of aortic insufficiency in persons, usually males, over forty-five
+years, who did not have chronic infective endocarditis, the Wassermann
+reaction was positive. Acute aortitis affecting the ascending and
+transverse portions of the arch of the aorta is very commonly seen, and
+the irregular, scattered, slightly raised, yellowish-white patches of
+sclerosis in the arch which are found years after the syphilitic lesion,
+are considered by some to be very characteristic of syphilis.
+Mesaortitis is the primary lesion and acts as a _locus minoris
+resistentiae_ where an aneurysm forms.
+
+Hypertensive cardiovascular cases have been serologically studied, and a
+positive Wassermann reaction found in a large percentage of one series.
+In fifty cases, 90 per cent either gave a positive Wassermann reaction
+or luetin test, were known to have syphilis, or had children with
+hereditary syphilis. This suggests what might be called "familial
+cardiovascular syphilis."
+
+Hypertensive disease is possibly one of the common so-called "late"
+manifestations of syphilis. That syphilis is responsible for the
+arterial disease in the vessels of the brain, resulting in apoplexy or
+sudden cardiac death in middle life, has long been known. In fact, it is
+claimed (Osler) that all aneurysms occurring in persons under thirty
+years of age are due to syphilitic aortitis. In the late stages of
+syphilis the arterial lesions may be of a diffuse character.
+
+
+=Chronic Drug Intoxications=
+
+Lead, tobacco, and according to some, tea and coffee, are to be classed
+as causal factors in the production of arteriosclerosis. Certain it is
+that all these substances have a tendency to raise the arterial
+pressure, but whether the drug itself causes first a degeneration, and
+later a hypertension results, or vice versa, is not yet positively
+known. We have just mentioned that lead particularly has a marked effect
+in producing arterial lesions. Other drugs as adrenalin, barium
+chloride, physostigmin, etc., while producing experimental
+arteriosclerosis, hardly could produce the disease in man. =Alcohol= has
+been blamed for much, and as an etiologic factor in the production of
+arteriosclerosis formerly was accorded a first place. More recently much
+doubt has been thrown on this supposition by the work of Cabot, who
+showed that the mere drinking of even large quantities of spirits had no
+effect in producing arterial disease.
+
+This observation has been recently substantiated by Hultgen, who
+carefully studied clinically 460 cases of chronic alcoholism. He says,
+"There are no cardiovascular symptoms which might be termed
+characteristic of chronic alcoholism, unless it be the peculiar fetal
+qualities of the heart sounds which we know as embryocardia. I find this
+very frequent among drinkers, but I can offer only a tentative
+explanation for it, namely the following: Embryocardia can only occur
+with low tension blood pressure, and in the absence of renal
+insufficiency. Hence it might be considered as a useful condition of no
+pathologic significance at all. That alcohol is a sclerogenic pharmakon
+and productive of arteriosclerosis with its usual train of symptoms may
+be a fact, but its demonstration would be difficult and is really not
+shown by my tabulations. There were cardiovascular changes, such as
+myocarditis, aortitis, valvular heart disease and arteriosclerosis in
+chronic alcoholics in 54.3 per cent of 461 cases, but this by no means
+constitutes a proof of the causal relationship between these lesions and
+the abuse of liquors. I believe it, nevertheless, to be good reasoning
+to ascribe the bulk of cardiovascular symptoms to the sclerogenic action
+of alcohol, while abstaining from an interpretation of its
+pathogenesis." Just what role =tobacco= plays is difficult to say. My
+own opinion is, that of itself when used in moderation, it has no ill
+effects. However, as tobacco is a drug that may raise the blood
+pressure, excessive use must be held responsible for the production of
+arteriosclerosis. It is difficult to separate its effects from those
+produced by eating and drinking.
+
+
+=Overeating=
+
+There can be no doubt but that the constant overloading of the stomach
+with rich or difficultly digestible food is responsible for a large
+number of cases of arteriosclerosis. Every one must have noted the
+increase in force and volume of the heart beat after the ingestion of a
+large meal. The constant repetition of such processes conceivably can
+lead to damage to the vessel walls through hypertension.
+
+In the metabolism of food in the intestines there are substances
+produced which are poisonous when absorbed directly into the
+circulation. Ordinarily these substances are rendered harmless either
+before absorption or are detoxicated in the liver to harmless
+substances. It is conceivable that a constant overproduction of such
+poisons would eventually damage the defensive mechanism of the body to
+such an extent that some of the poisons would circulate in the blood. An
+expression of a surplus of one, at least, of these decomposition
+products is the appearance of indican in the urine. It is not believed
+that indicanuria has the importance attached to it which some authors
+would have us believe. It is found too often and in too many varying
+conditions, nevertheless it undoubtedly does reveal the presence of
+perverted metabolism.
+
+In how far the toxins absorbed from the intestinal tract are responsible
+for the production of arterial disease, it is not possible to say. Some
+observers lay great stress on this factor as a cause of
+arteriosclerosis. The author believes that the role played by the
+absorption of products of perverted intestinal metabolism is an
+important one. The primary change is an increased tension in the
+arterioles which later leads to thickening of the coats of the vessels
+and to the other consequences of arterial disease. A vicious circle is
+thus established which has a tendency to become progressively worse.
+
+
+=Mental Strain=
+
+More and more does one become impressed with the fact that patients with
+arteriosclerosis are very often those who take life too seriously and
+either from ambition or from an exalted sense of duty lead especially
+strenuous lives. Not always are these persons addicted to drug or liquor
+habit. Many are rather abstemious in their habits. It is not so often
+that we see as a victim of arteriosclerosis, the carefree person who
+laughs his way through life without worrying about the morrow. He is not
+so prone to arteriosclerosis. Worry is a far more potent cause of
+breakdown than actual manual work. It is the rule to find thickened
+arteries among neurasthenics. This may be only part of a generalized
+degeneration of all tissue in the body. The blood pressure in such
+persons is usually low. So many men of our better class live under a
+continuous mental strain in the business world. The increase in
+arteriosclerosis cases is real, not apparent. The intense mental strain
+seems to cause a marked increase in blood pressure (for short periods of
+mental effort this has been proved) over a period of time sufficient to
+cause permanent changes in the vessel walls. The same sequence of events
+repeats itself; high tension, arterial strain, compensatory thickening,
+hypertrophied heart, etc.
+
+Certainly the character of the arterial tissue has much to do with the
+determination of degenerative changes which may result from the action
+of one or more of the etiologic factors.
+
+
+=Muscular Overwork=
+
+Muscular overwork is to be reckoned with as an etiologic factor. One
+sees it especially among the laboring class in both whites and negroes.
+Possibly other factors, as alcohol and coarse heavy food, contribute to
+the early arterial degeneration. Hypertrophy of the heart occurs in
+athletes, and statistics gathered among the oarsmen especially, show a
+relatively high mortality at the different decades traceable to the high
+tension produced while in training. This question deserves more
+consideration than has been accorded it.
+
+
+=Renal Disease=
+
+Chronic disease of the kidneys (contracted red kidney) is one of the
+most certain producers of hypertension; in fact, some maintain that high
+tension, even without demonstrable kidney lesions, as revealed by
+careful urine examinations, is a valuable sign pointing to chronic
+nephritis. This is doubted by others, myself among them. Just what
+causes the increase in blood pressure sometimes to over 270 mm. of Hg,
+is not definitely known. It seems most probable that it is some poison
+elaborated by the diseased kidneys and absorbed into the general
+circulation. There it acts primarily on the musculature of the
+arterioles causing tonic contraction and an increase of work on the part
+of the heart to force the blood through narrowed channels. One fact is
+certain. We see patients in coma due to renal disease with blood
+pressure much over 200 mm of Hg. As these cases clear up, the pressure
+may fall, and should they seemingly recover, the recovery is accompanied
+with a marked decrease in blood pressure, finally reaching the normal
+for the individual. Moreover, in the course of a severe acute or
+subacute nephritis, hypertension is associated with headache, partial or
+total blindness, and drowsiness. When the pressure is reduced, all these
+symptoms disappear.
+
+There is also the chronically shrunken and scarred kidney known
+pathologically as the arteriosclerotic kidney. It is probable that there
+are two groups of cases which we may designate: (1) primary; (2)
+secondary. In the primary group the kidney disease antedates the
+sclerosis of the arteries, and the sclerosis is most probably dependent
+on the constant high tension. We know that prolonged hypertension will
+produce severe forms of arteriosclerosis. The arterial disease in this
+group is caused by the renal disease.
+
+In the second group the kidney changes are apparently due to the general
+arteriosclerosis which, affecting the kidney vessels, causes changes
+leading to atrophy and subsequent fibrous tissue ingrowth of scattered
+areas. These cases are not necessarily associated with hypertension; on
+the contrary there is more apt to be hypotension. Where the first group
+occurs for the most part in young and active middle-aged people, the
+second group is the result of involutionary processes which accompany
+advanced age.
+
+However careful a urinalysis may be, there is no assurance that one can
+predict the pathologic state of the kidney. Often so-called normal urine
+will be secreted by a badly diseased kidney, whereas a urine which
+contains considerable albumin and many casts may be secreted by a kidney
+which is only temporarily the seat of inflammation. What matters after
+all is not the state of the kidney which the pathologist describes, but
+the actual functional response of the kidney in the body to the various
+tests now well known.
+
+
+=Ductless Glands=
+
+At the present time the tendency among some writers is to make the
+ductless glands the responsible agents in almost all diseases.
+Arteriosclerosis is no exception to this tendency. Sajous, for example,
+divides the morbid process producing arteriosclerosis into three types;
+(1) autolytic, (2) adrenal, (3) denutrition. In the first type he finds
+the pancreas to be the most important gland. It supplies an internal
+secretion which "takes a direct part in the protein metabolism of the
+tissue cells, and also in the defensive reactions within these cells, as
+well as in the phagocytes and in the blood stream." This being the case
+exaggeration of this digestive process has tissue destruction as its
+result, arteriosclerosis among them.
+
+In the adrenal type Sajous argues that adrenalin produces lesions
+experimentally, therefore the adrenal gland has a profound influence by
+its internal secretion in connection with the sympathetic system in
+producing degenerations leading to arteriosclerosis.
+
+The denutrition type has as its particular gland the thyroid. The
+sclerotic process in the arteries is due to the lack of thyroid as in
+cases of myxedema. After a long resume of his ideas he concludes "that
+arteriosclerosis is the result of excessive or deficient activity of
+certain ductless glands, the thyroid and adrenal in particular."
+
+No one can dogmatically deny the part which the ductless glands may play
+in the production of arteriosclerosis, but it hardly seems that there is
+enough actual experimental evidence to show that they take such an
+important part as Sajous believes. Until further and more convincing
+evidence is offered by competent investigators, I prefer to look with
+some skepticism upon the ductless gland theory of the causation of
+arteriosclerosis. The field lends itself too easily to speculation and
+imagery. Some are already allowing themselves the mental debauch of this
+nature.
+
+
+
+
+CHAPTER VII
+
+THE PHYSICAL EXAMINATION OF THE HEART AND ARTERIES
+
+
+=Heart Boundaries=
+
+In order to be able to estimate the departures from normal in the
+boundaries of the heart, it is essential that there be a definite
+appreciation of the boundaries of the normal heart in relation to the
+chest wall.
+
+It is frequently stated that the right limit of cardiac dullness is
+normally, in the adult, just at the right border of the sternum. This is
+not strictly accurate. Careful dissections at the autopsy table and
+x-ray plates of the chest made at a distance of two meters from the tube
+show that the border of the right auricle is from one to one and a half
+and even two centimeters from the edge of the sternum at the level of
+the fourth rib, and on the living subject this can be also demonstrated.
+The right border of the heart usually is from 3 to 4 cm. from the
+midsternal line at the level of the fourth rib.
+
+Again there is a term used in defining the apex, known as the point of
+maximum impulse. As this does not always coincide with the apex beat and
+with the outer lower left border of the heart, it would be better to use
+the term apex beat.
+
+Normally, then, the cardiac dullness, the so-called relative cardiac
+dullness, begins above at the upper border of the third costal
+cartilage, as a rule, and taking a somewhat curved line with the
+concavity inward, descends to the fifth interspace or beneath the fifth
+rib from 9 to 10 cm. from a line drawn through the center of the sternum
+parallel to its length, the midsternal line. This seems to me to be a
+better method of recording the size of the heart than by the lines
+commonly used; viz., the nipple, or midclavicular, or parasternal line.
+Below, the cardiac dullness is merged into the tympany from the stomach
+and the dullness from the liver. At the sixth right costosternal
+articulation there is a sharp turn upwards forming at that point with
+the liver the cardiohepatic angle. At the fourth right cartilage or the
+third interspace, the dullness is from one to two centimeters from the
+edge of the sternum. We have then a somewhat pear-shaped area or
+triangular area with the apex at the apex of the heart. The so-called
+absolute cardiac dullness does not appear to me to be of any great
+significance. In reality it is the limit of lung resonance and may be
+greater or less, not so much on account of variations in the size of the
+heart, as of variations in size of the lungs and shape of the chest
+wall.
+
+The really crucial question which should always be asked is, Is the
+heart enlarged or decreased in size? The position of the apex beat alone
+can not determine this, neither can the limit to the right of the
+sternum. The distance between these two points and the depth of the
+dullness at a distance of 5 cm. from the midsternal line on the left
+side, will give the size of the heart as nearly as can be obtained in
+the living subject. A series of measurements in normal adults average 13
+to 14 cm. and 9 to 10 cm. respectively. For women they are about 1 cm.
+less in each direction.
+
+The elaborate mechanism known as the orthodiagraph is probably the best
+means of determining the actual limits of the heart, but few men have
+such an expensive instrument, and, moreover, at the bedside such an
+instrument could not be used. From comparative measurements I concur in
+the belief of those who affirm that careful percussion will furnish
+equally as accurate limits.
+
+The first step in making an examination of the heart is to expose the
+patient's chest in a good light, and, sitting at his right side,
+carefully inspect the chest. The position of the apex beat, heaving,
+bulging, retraction of interspaces, etc., can easily be seen if
+visible. After careful inspection has given all the data which it is
+possible to obtain, one next lays the palm of the hand over the heart
+and attempts to palpate the apex beat. The thrust of the apex in a
+hypertrophied heart can readily be felt, and one can feel whether the
+heart is regular, irregular, intermittent, or has other change in
+rhythm. The shock of the closing valves, particularly the aortic, can be
+felt, and that and the forcible apical impulse are very suggestive signs
+of hypertrophy and hypertension. Thrills may also be felt and can be
+timed in relation to the heart cycle.
+
+
+=Percussion=
+
+It is to percussion that we next proceed, and for the data in regard to
+the size of the heart, it is, for our purpose, the most valuable of all
+the physical methods of heart examination.
+
+First and foremost we wish by percussion to learn the actual size of the
+heart, in other words what is ordinarily called the relative cardiac
+dullness. With the absolute dullness we are not concerned. That
+irregular area represents, as has been said, actually the =limits of
+lung resonance=. The heart may or may not be covered with lung; there
+may or may not be the incisura cardiaca. What I wish to insist upon is
+that the size of the area of absolute dullness can give us no data in
+regard to the size of the heart. What we must endeavor to learn is the
+actual size of the heart as nearly as our crude means will permit.
+
+Light, very light, almost inaudible percussion, what Goldscheider called
+"Schwellungsperkussion," must be practiced. Use the middle finger of the
+right (left) hand as the hammer and the last joint of the middle finger
+of the left (right) hand pressed firmly against the chest, as
+pleximeter. I believe it is better to place the pleximeter finger
+parallel to the boundary to be limited although some place the finger
+perpendicularly, that is, pointing toward the boundary. Now and then it
+helps to bend the pleximeter finger at the second joint, hold it
+perpendicularly to the chest wall, and strike the joint directly in line
+of the finger. This in my hands has been of great assistance in
+percussing the limits of the heart dullness. Pottenger's "light touch
+palpation" is a modification of the light palpation and, to my mind, has
+no very special advantages. Auscultatory percussion is of great value at
+times. The bell of the stethoscope is placed over the portion of heart
+uncovered by lung (should such be the case), and with this point as a
+center the chest is lightly and quickly tapped along radii converging
+toward the stethoscope. One soon learns to recognize the change of pitch
+as the tapping reaches the border of the heart. It is well to use all
+methods, especially in difficult cases, and to compare the results.
+Personally I have found that by light percussion I can limit with much
+accuracy the upper, right, and left borders of the heart.
+
+There is much to be gained by using light percussion. Strong blows set
+in vibration not only the underlying structures, but also more or less
+of the chest wall. We wish to avoid this source of error, we do not wish
+to differentiate by pitch alone. Finally one's pleximeter finger
+becomes, after long practice, so sensitive to changes in the resonance
+of structures lying below it, that there is actual feeling of impairment
+to the slightest degree. This delicate touch is what we should endeavor
+to cultivate.
+
+It is at times of advantage to use immediate percussion. This is done by
+bending the fingers of the striking hand, bringing the tips in a line
+and striking the chest lightly with the four fingers as one finger. Some
+find it easier to percuss the dullness due to the heart in this way than
+by mediate percussion.
+
+The little hammer and hard rubber, celluloid, bone, or ivory pleximeter
+does not seem to me to be nearly as good as the fingers. Moreover, one
+always has his hands, but may forget his hammer and pleximeter.
+
+
+=Auscultation=
+
+In auscultating the heart I prefer the binaural stethoscope of the Ford
+pattern. The recent substitution of an aluminum bell for the hard rubber
+bell is an improvement. Personally I do not favor the phonendoscope or
+any of the new patent non-roaring instruments now for sale by urgent
+instrument makers. The phonendoscope has its uses, for example in
+auscultating the back when a patient is lying in bed or in listening to
+the heart sounds when a patient is under an anesthetic; but for
+differentiating the murmurs and for heart diagnosis, I much prefer the
+regular bell stethoscope.
+
+In arteriosclerosis the two places over which it is important to listen
+are the apex and the second right cartilage, the aortic area. Over the
+former, one gains data in regard to the strength of the heart as
+indicated by the first sound, over the latter point, one learns of the
+tension in the aorta by the character of the sound produced when the
+aortic valves close.
+
+The hypertrophy of the heart in arteriosclerosis is invariably due to
+the enlargement and thickening of the left ventricle. From the nature of
+the position which the heart assumes in the thorax, this enlargement is
+downward and to the left. The apex beat will therefore be found in the
+fifth or sixth interspace, and definitely at an increased distance from
+the midsternal line. As stated above, it is most important that this
+distance be accurately measured and put down in the notes of the case
+for future reference. No satisfactory prognosis can be given unless this
+is done, for the gradual increase or the decrease under treatment in the
+size of the heart can thus be definitely known, and, knowing the other
+factors, a prognosis may be given which will be of some value to the
+patient.
+
+
+=The Examination of the Arteries=
+
+It is exceedingly difficult at times to affirm definitely that an
+artery, the radial for example, is actually sclerosed. Much depends on
+the sensitiveness of the fingers of him who palpates, and much upon the
+relation of the palpated artery to the surrounding, chiefly underlying,
+structures. In the examination of arteries it is well to inspect the
+body for the pulsations caused by them. Frequently an exceedingly
+tortuous artery, such as the brachial, may be seen throughout its whole
+extent and yet the radial appear little, if any, thickened by palpation.
+Again the artery of a pulse of high tension which is small in size but
+full between the beats, may not be as sclerosed as one which collapses
+and feels much softer. It is difficult to obtain accurate data in regard
+to the tension in an artery by feeling it with the fingers of one hand.
+One should use both hands. With the middle finger of the right (left)
+hand the artery is compressed peripherally, that is, nearest the wrist.
+The blood is then pressed out of the artery with the middle finger of
+the left (right) hand, so as to obliterate completely the pulse wave and
+the two or three inches between the middle fingers are felt with the
+index fingers. By holding the finger firmly on the artery near the wrist
+so as to block any wave that may come through the palmar arch by
+anastomosis with the ulnar artery and by releasing pressure on the
+proximal middle finger, some idea may be had of the degree of pulse
+tension. However, no amount of practice can more than approximate the
+tension and when one is surest that he can tell how many millimeters of
+pressure there are, he is apt to be farthest wrong when he checks his
+guess with the sphygmomanometer.
+
+Much may be learned from carefully palpating the peripheral arteries,
+and, as a rule, the sclerosis of these arteries means general
+arteriosclerosis, although there are many exceptions to this.
+
+A more recent method, and one which in the author's hands has been found
+to be valuable, is that proposed by Wertheim-Salomonson who palpates the
+artery not with the ball of the finger but with the fingernail. The
+finger is held so that the nail is perpendicular to the surface of the
+skin and the artery is felt with the end of the nail. The sensation is
+perceived at the root and makes use of all the sensitive nerve endings
+there. In this way it is possible to feel the arterial wall distinctly,
+and a little practice will enable one to determine whether or not the
+vessel wall is thickened. It is also possible to determine with a
+considerable degree of accuracy the diameter of the artery and the size
+of the wall when the current is cut off by pressure on the proximal side
+of the artery. It is best to have a firm background when this
+"fingernail" palpation is used. This may be obtained by palpating the
+radial artery against the lower end of the radius.
+
+Probably the best method of palpating the arteries, especially the
+radial, to determine the degree of sclerosis and thickening, is to use
+the tip of the finger and roll it carefully over the artery. The tip of
+the finger is exceedingly sensitive and, moreover, it is a firmer
+palpating surface than the ball, thus enabling one to appreciate degrees
+of sclerosis which could not be differentiated by palpation with the
+soft yielding ball. This finger tip palpation is well illustrated in the
+figures here shown. (Figs. 57 and 58.)
+
+[Illustration: Fig. 57.--A method of finger-tip palpation of the radial
+artery. (Graves.)]
+
+[Illustration: Fig. 58.--Another method of finger-tip palpation of the
+radial artery. (Graves.)]
+
+
+=Estimation of Blood Pressure=
+
+It must be borne in mind at the outset that arteriosclerosis and high
+blood pressure are not always associated. As a matter of fact in the
+severest grades of senile arteriosclerosis the blood pressure is usually
+below the normal for the individual's years. However, as high tension is
+a frequent factor in the production of arterial thickening, blood
+pressure readings are of importance.
+
+The instrument which one uses is of minor importance provided it is
+properly standardized. The most important feature of the instrument is
+the cuff. This must be 12 cm. wide and be long enough to wrap around the
+arm several times so that the pressure is evenly distributed over the
+whole arm and not over a small portion. One mercury instrument we had in
+the hospital was reported to be at great variance with a dial
+instrument. This mercury instrument was provided with a cuff which was
+short and was tied around the arm by means of a piece of tape. This
+caused a tight constriction over a small area and rendered the
+estimation too high. A new, long tailed cuff easily remedied the
+apparent defect in the instrument.
+
+In taking blood pressures the difference from day to day of 10 or even
+15 mm. of systolic pressure has no great significance. Fluctuations of
+the systolic pressure alone, it is insisted upon, have very little
+meaning. One must take the whole pressure picture into consideration and
+determine how the picture changes in order to draw any conclusion in
+regard to the state of the blood pressure. Failure to pay attention to
+this evident point has caused much futile work to be written and
+published.
+
+It is well to emphasize again the point that the blood pressure picture
+consists of the systolic, the diastolic, the pulse pressure and the
+pulse rate.
+
+
+=Palpation=
+
+Hoover has called attention to the direct palpation of the femoral
+artery just below Poupart's ligament as a more accurate index of the
+pressure in the aorta than the palpation of the radial artery. Possibly
+one can obtain a more accurate estimate of the blood pressure in this
+way. This, however, is open to dispute. To estimate the blood pressure
+by palpating the radial artery is most deceptive. In about 75 per cent
+of cases one can tell fairly well whether the pressure is abnormally
+high or abnormally low. Small variations are impossible to determine.
+Unquestionably it is most advantageous to get into the habit of
+palpating the femoral artery and checking the result with the
+sphygmomanometer so that the fingers may be trained to appreciate as
+accurately as possible changes of pressure.
+
+It may be that one day when the instrument is needed it is not at hand.
+A well-trained touch then becomes a great asset.
+
+
+=Precautions When Estimating Blood Pressure=
+
+There are certain precautions which must be strictly observed when
+deductions are drawn from the manometer readings. The psychic factor
+must be reckoned with. Any emotion may cause marked variations in the
+pressure. Excitement and anger are especial sources of error. Even the
+slight excitement arising from taking the first blood pressure on a
+nervous patient especially is apt to give false values. Usually the
+readings must be taken many times at the first sitting and the first few
+may have to be set aside. Worry is a potent factor in raising the
+pressure. A walk to the physician's office, especially if rapid, has its
+effect.
+
+The position of the patient when the blood pressure is taken is
+important. Usually in the office the pressure is taken when the patient
+sits in a chair. He should assume a relaxed, comfortable attitude. The
+readings should be made at the same time of day and at the same interval
+between meals. The pressure in both arms should be measured and
+comparisons should be made only between readings on the same arm. These
+precautions may seem useless and even somewhat trivial, and the
+conditions difficult to control. But unless they are carefully observed
+the readings will be false, no comparisons can be drawn between the
+readings on different days, and the instrument will most probably be
+blamed. I have known this to happen so often that I can not emphasize
+too strongly the importance of controlling all the essential conditions
+which go to make accurate work.
+
+
+=The Value of Blood Pressure=
+
+In the past few years there has been a veritable avalanche of blood
+pressure instrument salesmen who have covered the country, sold
+instruments, and have made many startling claims for the instrument.
+They have emphasized its value out of proportion to what the instrument
+can do even in the hands of one familiar will all the defects.
+Consequently it is not necessary to emphasize the value of blood
+pressure. It seems best to utter a few words of caution in regard to its
+interpretation.
+
+The value lies not in the occasional estimation compared with some other
+one reading, but in the frequent estimation and in the visualization of
+the blood pressure picture. For the great majority of diseases the blood
+pressure has no particular value except to show that the circulation is
+not materially disturbed. The limits of normal are rather wide, so that
+consideration of the patient's age, sex, build, etc., will give us some
+idea of a base line, so to speak, for any one person. Wide departures
+from relatively normal figures are important, but are not diagnostic or,
+rather, pathognomonic. I can not help but feel that the diastolic
+pressure is _the_ most important part of the blood pressure picture.
+Persistent high diastolic pressure means increased work for the heart,
+which, if acting for a long time against the high peripheral resistance,
+must eventually hypertrophy. The arteries become thickened, lose their
+wonderful elasticity, fibrous tissue is deposited in their walls, and
+the vicious circle is established which leads to pathologic
+hypertension.
+
+Blood pressure readings must be intimately mixed with brains in order to
+be of any great value in diagnosis or prognosis.
+
+
+
+
+CHAPTER VIII
+
+SYMPTOMS AND PHYSICAL SIGNS
+
+
+=General=
+
+Well developed arteriosclerosis shows four pathognomonic signs: (1)
+hypertrophy of the heart; (2) accentuation of the aortic second sound;
+(3) palpable thickening of the arteries; and (4) heightened blood
+pressure. However, it must not be inferred that these signs must be
+present in order to diagnose arteriosclerosis. It has already been said
+that a very marked degree of thickening, with even calcification of the
+palpable arteries, may occur with absolutely no increase of blood
+pressure, and at autopsy a small flabby heart may be found.
+
+While arteriosclerosis is usually a disease which is of slow maturation,
+nevertheless cases are occasionally seen which develop rather rapidly.
+The peripheral arteries have been noticed to become stiff and hard in as
+relatively brief a time as two years from the recognized onset of the
+disease.
+
+Since involution processes are physiologic, as has been described (vide
+infra), arteriosclerosis may assume an advanced grade and run its course
+devoid of symptoms referable to diseased arteries. It is doubtful
+whether the sclerosis itself could produce symptoms, except in cases
+later to be described, were it not that the organs supplied by the
+diseased arteries suffer from an insufficient blood supply and the
+symptoms then become a part of the symptom-complex of any or all the
+affected organs.
+
+There are cases, however, in comparatively young persons where a
+combination of certain ill-defined symptoms gives a clue to the
+underlying pathologic processes. These symptoms of early
+arteriosclerosis are the result of slight and variable disturbances in
+the circulation of the various organs. Normally there are frequent
+changes in the blood pressure in the organs, but the vasomotor control
+of normal elastic vessels is so perfect that no symptoms are noted by
+the individual. When the arteries are sclerosed, they are less elastic
+and the blood supply is, therefore, less easily regulated. At times
+symptoms occur only after effort. The patient may tire more readily than
+he should for a given amount of mental or bodily exercise; he is weary
+and depressed, and occasionally there is noted an unusual intolerance of
+alcohol or tobacco. Vertigo is common, especially on rising in the
+morning or in suddenly changing from a sitting to a standing position.
+Some complain of constant roaring or ringing in the ears. There may be
+dull headache that the accurate fitting of glasses does not alleviate.
+Unusual irritability or somnolency with a disinclination to commence a
+new task may be present. Sometimes the effort of concentrating the
+attention is sufficient to increase the headache. This has been called
+"the sign of the painful thought." Numbness and tingling in the hands,
+feet, arms, or legs are also complained of, and neuralgias, not
+following the course of the nerves but of the arteries, also occur. It
+is important to remember that the train of symptoms resembling
+neurasthenia in a person over forty-five years old may be due to
+incipient arteriosclerosis. This tardy neurasthenia frequently
+accompanies cancer, tuberculosis, diabetes, and incipient general
+paralysis, as well as incipient arteriosclerosis.
+
+Bleeding from the nose, epistaxis, taking place frequently in a
+middle-aged person, sometimes is an early symptom. The bleeding may be
+profuse, but is rarely so large as to be positively harmful. In fact, it
+may do much good in relieving tension. Slight edema of the ankles and
+legs is seen. Dyspnea on slight exertion is not uncommon. Dyspeptic
+symptoms are not infrequent, pyrosis (heartburn), a feeling of fullness
+after meals with belching or a feeling of weight in the epigastrium.
+The dyspeptic symptoms may be so marked that one might almost speak of a
+variety of arteriosclerosis, the dyspeptic type. For quite a while
+before any symptoms that would definitely fix the case as one of
+undoubted arteriosclerosis, the patient complains that foods which
+previously were digested with no difficulty now give him gastric
+distress. The examination of the stomach contents of a patient
+presenting gastric symptoms reveals usually a subacidity. The total
+acidity measured after the Ewald test meal may be only 20 and the free
+HCl may be absent. Attention has been called to an unnatural pallor of
+the face in early arteriosclerosis. Progressive emaciation is sometimes
+seen in cases of arteriosclerosis and may be the only symptom of which
+the patient complains.
+
+
+=Hypertension=
+
+Not all cases of arteriosclerosis are accompanied by increased arterial
+tension. As has been stated in a previous chapter, the blood pressure in
+the arterial system depends chiefly on two factors; viz., the degree of
+peripheral (capillary) resistance, and the force of the ventricular
+contraction. The highest arterial pressures recorded with the
+sphygmomanometer occur not in pure arteriosclerosis but in cases where
+there is concomitant chronic interstitial disease of the kidneys. When
+this is found there is always arteriosclerosis more or less marked. In
+cases where the arteries are so sclerosed that they feel like pipe stems
+there may be an actual decrease in the blood pressure. Hence the
+clinical measuring of the pressure in the brachial artery alone is not
+sufficient for a diagnosis of arteriosclerosis. A persistent high blood
+pressure even with normal urinary findings is not a sign of
+arteriosclerosis. The high tension later may lead to the production of
+sclerosis of the arteries, but in these cases the kidney may be
+primarily at fault.
+
+The impression must not be gained that hypertension in itself always
+constitutes a disease or even a symptom of disease. Hypertension itself
+is practically always a compensatory process. That is to say, it is the
+attempt on the part of the body to equalize the distribution of blood in
+the body when there is some poison causing constriction of the small
+arteries. In this sense hypertension is not only essential, but actually
+life-saving. A heart which is so diseased that it can not respond to the
+call for increased action by hypertrophy of its fibers, would shortly
+wear out. The very fact that the heart becomes enlarged and the tension
+in the arteries becomes high, indicates that in such a heart there was
+great reserve power. But while hypertension is largely an effort at
+adjustment among the various parts of the circulation, it nevertheless
+tends to increase, provided the cause or causes which produced it act
+continuously. Moreover, as has been said (Chap. II), the arterioles do
+not respond to increased work on the part of the heart by expanding, but
+by contracting. A vicious circle is thus maintained which eventually
+must lead to serious consequences.
+
+Hypertension is then, if anything, only a symptom which may or may not
+demand treatment. That hypertension leads to the production of sclerosis
+of the arteries has been repeatedly affirmed here. In certain cases it
+is good and should not be experimented with. In other cases it is bad
+and some treatment to reduce the tension must be tried. The main point
+is to regard hypertension as one regards a compensated heart lesion.
+
+Prof. T. Clifford Allbutt divides the causes of arteriosclerosis
+clinically into three classes: (1) The toxic class--the results of
+poisons of the most part of extrinsic origin, chiefly those of certain
+infections. In some of these diseases, the blood pressures, as for
+example, in syphilis, are ordinarily unaffected; in others, as in lead
+poisoning, they are raised. (2) The class he calls hyperpietic,[15] in
+which an arteriosclerosis is the consequence of tensile strength, of
+excessive arterial blood pressure persisting for some years. A
+considerable example of this class is the arteriosclerosis of granular
+kidney, but in many cases kidney disease is, clinically speaking,
+absent. (3) The involutionary class, in which the change depends upon a
+senile, or quasisenile degradation. This may be no more than wear and
+tear, a disposition of all or of certain tissues to premature
+failure--partly atrophic, partly mechanical--under ordinary stresses; or
+it also may be toxic, a slow poisoning by the "faltering rheums of age."
+In ordinary cases of this class the blood pressures for the age of the
+patient are not excessive. Although the toxins of the specific fevers,
+notably typhoid, as stated above, and influenza, have been shown to
+produce arteriosclerosis, this, under favorable circumstances he
+believes tends to disappear. This has been shown by Wiesel.
+
+ [15] From pieso to squeeze, oppress or distress. Hyperpiesis,
+ therefore, signifies excessive pressure.
+
+As the blood pressure is dependent on the resistance offered by the
+capillaries and arterioles, there are only two ways in which increased
+pressure can be brought about; either by rendering the blood more
+viscous, or by the generation of some poison from the food taken into
+the body which, acting on the vasomotor center or directly on the finer
+vessels, arteriolar or capillary, sets up a constriction over any large
+area, and mainly in the splanchnic area. In regard to the liability to
+arteriosclerosis, this area stands second only to the aortic and
+coronary areas. He believes that arteriosclerosis itself has little
+effect in raising arterial pressure. Many cases are seen in which with
+extreme arteriosclerosis there was no rise in blood pressure, and some
+in which pressures have been rising even long before the appearance of
+arterial disease. Prof. Allbutt also believes that in the hyperpietic
+cases the arteries undergo a transient thickening, which can be removed
+if the causes can be reached and overcome.
+
+Clinically speaking, then, hyperpietic arteriosclerosis is not a
+disease, but a mechanical result of disease. If the narrowing of the
+arterioles is brought about by thickening due to arteriosclerosis, then
+it would seem _a priori_ that such obliteration should cause a rise in
+pressure. Were the vascular system a mere mechanical set of tubes and a
+pump, this would happen, but other factors of great importance must be
+taken into consideration besides the mechanical factors; viz., chemical
+and biological factors. Thus, whole parts may be closed and with
+compensatory dilatation in other parts there would be little or no
+change in pressure, unless there were hyperpiesis. In established
+hyperpiesis, we note two conditions in the radial artery: first, a
+comparatively straight vessel with a small diameter; secondly, a larger,
+more tortuous vessel, "the large leathery artery." In the cases of the
+first group, hyperpiesis is often more marked, although not appearing so
+to the examining finger, than in the second class. In view of the
+difficulty of estimating by touch alone the amount of hyperpiesis in a
+contracted hard artery, it is often overlooked until a ruptured vessel
+in the brain startles us to a realization of our mistake. The "narrow"
+artery is more dangerous than the tortuous one, for with every change in
+pressure the passive vessels of the brain must receive blood that under
+normal conditions would go to other parts of the circulation.
+
+In involutionary sclerosis there is a gradual thickening and tortuosity
+of the vessel, which although it may be greater than in the hyperpietic
+cases, yet is never so dangerous to life. The heart in hyperpiesis
+hypertrophies and dilates, but such a heart is the result, not an
+integral part, of the arterial disease.
+
+
+=The Heart=
+
+When the arterial tree becomes narrowed and the resistance offered to
+the flow of blood thereby is increased, more muscular work is required
+of the left ventricle and according to the general laws which govern
+muscles the ventricle hypertrophies. There is an actual increase in
+number of fibers as well as an increase in the size of the individual
+fibers. Some of the best examples of simple hypertrophy of the left
+ventricle are found under such circumstances. The chambers as a rule do
+not dilate until the resistance becomes greater than the contraction can
+overcome, when symptoms of broken compensation of the heart take place.
+The hypertrophy of the left ventricle brings more of this portion of the
+heart toward the anterior chest wall. The enlargement is toward the
+left, also, consequently the apex-beat is found below and to the left of
+its usual site, even an inch or more beyond the nipple line. The impulse
+is heaving, pushing the palpating hand forcibly up from the chest wall.
+The visible area of pulsation may occupy three interspaces and the
+precordium is seen to heave with every systole. On auscultation the
+second sound at the aortic cartilage is ringing, clear, and accentuated.
+Not infrequently, too, the first sound is loud and booming, but has a
+curious muffled sound that may even be of a murmurish quality. The
+leaflets of the mitral valve may be the seat of sclerosis, the edges are
+slightly thickened and do not quite approximate, thus causing a definite
+murmur with every systole. This murmur may be transmitted out into the
+axilla and be heard at the inferior angle of the left scapula.
+
+
+=Palpable Arteries=
+
+Not every artery that can be felt is the subject of arteriosclerosis,
+and, as has been stated, palpable arteries being more or less a
+condition of advancing years, judgment as to whether the artery is
+pathologically or physiologically thickened may be a matter of
+individual opinion. A radial artery that lies close to the lower end of
+the radius and can actually be seen to pulsate when the hand is held
+slightly extended on the back of the wrist, is easily felt, but must
+not, therefore, be considered a sclerosed artery. The radial may be so
+deeply situated in the wrist of a fat subject that it is difficultly
+palpable. Yet the two cases just described may have arteries of
+identical structure, there being no more retrogressive changes in the
+one than in the other. "Experience is fallacious and judgment
+difficult."
+
+The small, contracted, wiry artery of a chronic nephritic may feel like
+a pipe stem, but if properly felt the mistake will not be made of
+considering such an artery an unusually sclerosed one. When the wave is
+pressed out of such a high tension artery, it is found that what seemed
+to be a firm sclerosed vessel, was in reality an artery tightly
+stretched over the column of blood.
+
+
+=Ocular Signs and Symptoms=
+
+It would not exaggerate too much to say that the examination of the eye
+grounds with the ophthalmoscope is the most important aid in the early
+diagnosis of arteriosclerosis. Long before there are any subjective
+symptoms, changes can be seen in the blood vessels of the retina which,
+while not always diagnostic, at least call attention to a beginning
+chronic disease. As I become more proficient in the use of the
+ophthalmoscope, I am impressed with the importance of the ocular signs
+of arterial disease. I would urge practitioners to familiarize
+themselves with this instrument. The electrically lighted instruments on
+the market now have so simplified the technic that any physician should
+be able to see the grosser changes which take place in the arteries and
+veins of the retina and in the disc. Frequently the ophthalmologist is
+the first to recognize early arteriosclerosis. In the fundus are seen
+increased tortuosity of the retinal vessels and their terminal twigs
+with more or less bending of the vessels at their crossings. The
+arteries are terminal ones, and small patches of retinitis are therefore
+found. The changes have been divided into (1) suggestive, (2)
+pathognomonic.
+
+Under (1) are:
+
+(a) Uneven caliber of the vessels,
+
+(b) Undue tortuosity,
+
+(c) Increased distinctness of the central light streak,
+
+(d) An unusually light color of the breadth of the artery.
+
+Under (2) are:
+
+(a) Changes in size and breadth of the retinal arteries so that they
+look beaded,
+
+(b) Distinct loss of translucency,
+
+(c) Alternate contractions and dilatations in the veins,
+
+(d) Most important of all, the indentation of the veins by the stiffened
+arteries.
+
+There is yet another sign which appears to be pathognomonic. The
+arteries are pale, appear rigid and through the center, parallel to the
+course, is a rather bright, fine threadlike line. The appearance is
+known as the "silverwire" artery. It is particularly constant in
+hypertension where the most beautiful examples are seen.
+
+Moreover, there is the arcus senilis, the fine translucent to opaque
+circle surrounding the outer portion of the iris. Practically every one
+with a well-marked arcus senilis has arteriosclerosis, but vice versa
+not every one with even marked arteriosclerosis has an arcus senilis.
+
+In general, the symptoms are gradual loss of acute vision, and attacks
+of transient loss of vision. The explanation which has been offered for
+these phenomena is the contraction in a diseased central artery.
+
+
+=Nervous Symptoms=
+
+The onset of arteriosclerosis is, in the majority of cases, so insidious
+that certain nervous manifestations, due in all probability to
+disturbances in blood pressure, are present long before the actual
+sclerosis of the arteries can be felt. These nervous symptoms are at
+times the sign posts to show us the way to accurate diagnosis. There may
+be gradual increase in irritability of temper, inability to sleep,
+vertigo even extending to transient attacks of unconsciousness. Loss of
+memory for details frequently is an early symptom of sclerosis of the
+cerebral arteries. Nervous indigestion may be present. Various
+paresthesias as numbness, tingling, a sense of coldness or of heat or
+burning, a sense of stiffness or even actual stiffness or weakness may
+occur in the arms and legs, more frequently in the legs. The pain
+complained of may be due to occlusion of an artery, although evidence
+for this is lacking. It has been thought by some that the pain in angina
+pectoris might be due to this cause.
+
+Several curious and interesting diseases which have been thought by some
+to have arteriosclerosis as a basis are accompanied by pain. Such are
+erythromelalgia, Raynaud's disease, "dead fingers," and intermittent
+claudication.
+
+Erb has reported a large series of intermittent limp (claudication) from
+his private practice. He finds that the large majority of the cases
+occur in men. The abuse of tobacco was evidently the main etiologic
+factor in about half of the cases. Repeated exposure to cold and the
+abuse of alcohol were responsible for most of the other cases. Curiously
+enough he finds that a history of syphilis was present in only a small
+proportion of his cases. It is his firm conviction that intermittent
+limping--which he thinks should be called angiosclerotic dysbasia--is
+frequently incorrectly diagnosed. It is mistaken for other troubles and
+treated wrongly. As gangrene may develop this is particularly dangerous.
+The affection generally develops gradually, although he has seen cases
+where the onset was rather acute. The partial or complete lack of the
+pulse in the foot is the one striking sign, together with the varying
+behavior of the pulse, its disappearance when the feet are cold and its
+return after a warm foot bath or under other treatment. Signs of general
+arteriosclerosis were present in nearly every case. When there is a
+tendency to the development of intermittent limp he finds that a
+valuable sign is the manner in which the leg blanches when it is lifted
+repeatedly while the patient is recumbent and becomes hyperemic later
+when placed horizontally. In health this change occurs more rapidly.
+
+
+
+
+CHAPTER IX
+
+SYMPTOMS AND PHYSICAL SIGNS
+
+
+=Special=
+
+Our conception of arteriosclerosis as a degenerative process affecting
+the vascular tree rather than a disease, removes the possibility of
+discussing special symptoms. As a matter of fact, we know of very few
+organs where even profound pathologic changes in the vascular system
+produced during life any symptoms which could be laid to these arterial
+changes. Kind nature has given to us such an excess of organs of every
+kind that the destruction of large portions of any organ seems to affect
+the function but little. So only particular groups of organs, which show
+symptomatic changes as the result of arteriosclerotic processes, will be
+discussed. It is realized that this may not give Teutonic completeness
+to the discussion, but it certainly saves paper and has a distinct
+practical value to the long suffering reader.
+
+Although arteriosclerosis is a disease which affects the whole arterial
+system, it nevertheless never reaches the same grade all over the body.
+The difference in the structure and functions of the various organs
+determines to great extent the eventual symptomatology. Endarteritis
+obliterans of a small sized artery in the liver or leg would lead to no
+marked symptoms, as the circulation is so rich that the anastomoses of
+the blood vessels would soon establish a collateral circulation that
+would be perfectly competent to sustain the function of the part. Quite
+different would it be should one of the small arteries of the brain, the
+lenticulo-striate, for example, which supplies the corpus striatum,
+become the seat of a thrombosis or embolism caused by arteriosclerosis.
+The arteries of the brain are terminal arteries and the blood supply
+would be cut off entirely with a resulting anemic necrosis of the part
+supplied by the artery and a loss of function of the part. What would be
+of no moment in the leg or arm might prove even fatal in the brain.
+
+The further symptomatology, therefore, of arteriosclerosis depends
+entirely on the organ or organs most affected by the interference with
+the blood supply. The following groups may be recognized:
+
+ 1. Cardiac.
+
+ 2. Renal.
+
+ 3. Abdominal.
+
+ 4. Cerebral.
+
+ 5. Spinal.
+
+ 6. Local vasomotor effects.
+
+ 7. Pulmonary.
+
+
+=Cardiac=
+
+Most cases of arteriosclerosis sooner or later present symptoms
+referable to the heart. When the organ is hypertrophied and is already
+working against an enormous peripheral resistance, a slight excess of
+work put upon it may cause a dilatation of the chambers with the
+resulting broken compensation. There is dyspnea on slight exertion,
+possibly some precordial distress, slight edema of the ankles and lower
+legs and possibly scanty urine. With proper care, a patient with such
+symptoms may recover, but the danger of another break in compensation is
+enhanced. The next attack is more severe. The edema is greater, there
+may be signs of edema of the lungs, effusions into the serous cavities
+may occur. The heart shows marked dilatation. There is gallop or canter
+rhythm and there are loud murmurs at the apex. When a patient is first
+seen in this stage, it may be quite impossible to state whether or not
+there is true valvular disease of the heart. The muscle is usually
+diseased in that there is fibroid degeneration of more or less
+extensive character. This factor causes the heart to lose much of its
+elasticity and increases the tendency to permanent dilatation. Such
+cases must be watched before one can say that true valvular
+insufficiency is not present. The fatal termination of such a case is
+quite like that of true valvular disease. There is increasing dyspnea,
+increasing anasarca, and the patient usually succumbs to edema of the
+lungs, drowned in his own secretions.
+
+[Illustration: Fig. 59.--Aneurysm of the heart wall. (Milwaukee County
+Hospital.)]
+
+A very rare complication of the fibroid degeneration of the heart muscle
+is aneurysm of the heart wall. (Fig. 59.) The apex of the left
+ventricle is most commonly the site of the aneurysm and rupture
+occasionally occurs. Such an accident is rapidly fatal. In the
+arteriosclerotic process which occurs at the root of the aorta, the
+coronary arteries become involved both at the openings and along the
+courses of the vessels. A branch or branches or even one artery may
+become blocked as a result of obliterating endarteritis. The arteries of
+the heart are not terminal vessels but as a rule blocking of a large
+branch leads to anemic infarct. These areas become replaced by fibrous
+tissue which in the gross specimen appears as streaks of whitish or
+yellowish color in the musculature. Anemic infarcts may not occur. In
+such cases the anastomosis between branches of the coronary arteries is
+unusually free. Through arteriosclerosis of the coronary vessels
+extensive fibrous changes may occur that lead to a myocardial
+insufficiency with its attending symptoms--dyspnea, irregular and
+intermittent heart, gallop rhythm, edema, etc. One of the most
+distressing and dangerous results of sclerosis of the coronary arteries
+and of the root of the aorta is angina pectoris. While in almost every
+case of angina pectoris there is disease of the coronary arteries, the
+contrary does not hold true, for most extensive disease, even embolism,
+of the arteries is frequently found in persons who never suffered any
+attacks of pain. This symptom group is more common in males than in
+females and as a rule occurs only in adult life. "In men under
+thirty-five syphilitic aortitis is an important factor." (Osler.)
+
+Since the valuable experiments of Erlanger on heart block, considerable
+attention has been paid to lesions of the Y-shaped bundle of fibers, a
+bundle arising at the auriculoventricular node and extending to the two
+ventricles, known also as the auriculoventricular bundle of His.
+Interference with the transmission of impulses through this bundle gives
+rise to the symptom group known as the Stokes-Adams syndrome, which is
+characterized by: (a) slow pulse, (b) cerebral attacks--vertigo,
+syncope, transient apoplectiform and epileptiform seizures, (c) visible
+auricular impulses in the veins of the neck. Many of the cases which
+occur are in elderly people the subjects of arteriosclerosis.
+
+[Illustration: Fig. 60.--Large aneurysm of the aorta eroding the
+sternum. Death from rupture through the skin preceded by frequent small
+hemorrhages. (Milwaukee County Hospital.)]
+
+So far as we now know all cases of the Stokes-Adams syndrome are caused
+by heart block which is only another name for disease in the
+auriculoventricular bundle. Of interest here is the fact that besides
+gummata, ulcers, and other lesions of the bundle, definite
+arteriosclerotic changes have been found.
+
+"The investigation of a typical case of Stokes-Adams disease has shown
+that the symptoms of this case are caused by some lesion in the heart
+which gives rise to the condition now generally termed heart block.
+Practically all degrees of heart block have been observed, namely,
+complete heart block and partial block with 4:1, 3:1, and 2:1 rhythm,
+and occasionally ventricular silences. These stages occurred during
+recovery.
+
+"Experiments testing the reaction of the heart to various extrinsic
+influences demonstrate that when the block is complete the ventricles do
+not respond to influences presumably of vagus origin, although the
+auricles still respond normally to such influences, that effects exerted
+upon the heart presumably through the accelerators still influence the
+rate of the ventricles as well as that of the auricles.
+
+"When the block is partial the rate of the ventricular contraction
+varies proportionally with the rate of the auricular contractions but
+only within certain limits. When these limits are exceeded the block
+becomes more complete, i. e., a 2:1 rhythm may be changed into a 3:1
+rhythm, this into a 4:1 rhythm, and this into complete block, and vice
+versa.
+
+"The syncopal attacks are, in all probability, directly dependent upon a
+marked reduction of the ventricular rate. Such reductions of the
+ventricular rate are always associated with an increase of the auricular
+rate, and it is believed that the latter is the cause of the former."
+(Erlanger.)
+
+The epileptiform seizures of the syndrome may be caused by the anemia of
+the brain resulting from failure of the heart to supply a sufficient
+quantity of blood.
+
+The apoplectiform attacks are most probably caused by venous congestion
+when the slowing of the ventricular contractions is not sufficient to
+cause convulsions, but will just cause complete unconsciousness.
+
+
+=Renal=
+
+Chronic nephritis, hypertension, arteriosclerosis form a most important
+trinity. Some stoutly affirm that in all cases of high tension there is
+chronic renal disease. Certainly the very highest blood pressures which
+we see occur in the chronic interstitial forms of kidney disease. The
+cause is most probably to be sought in some poison which is elaborated
+in the kidney, is absorbed into the circulation and acts powerfully
+either on the vasoconstrictor center as a stimulus, or directly on the
+musculature of the small arteries all over the body. Usually
+hypertension is progressive but it may be temporary.
+
+A man, 43 years old, entered the Milwaukee County Hospital in uremic
+coma. The systolic blood pressure was 280-290 mm. Hg, the diastolic
+pressure 220 mm. (Janeway instrument). Under treatment his blood
+pressure gradually became lower, at the same period the albumin and
+casts gradually disappeared from the urine. In two weeks from admission
+he seemed perfectly well, there were no albumin or casts found in the
+urine, and the systolic blood pressure was 136 mm., not a high figure
+for a muscular man of the laboring class. It must be admitted, however,
+that such cases are the exception, not the rule.
+
+Patients suffering from the association of chronic nephritis with
+hypertension die slowly, usually. There is gradual development of
+anasarca. Headache is frequent and severe. Pains all over the body may
+occur. The sight may suddenly become dim or may even be lost. Dizziness
+may be complained of and dyspnea is usually marked. Cyanosis comes on,
+the pulse becomes weak, irregular or intermittent, heart failure sets
+in, and the patient dies with edema of the lungs.
+
+Another class of renal arteriosclerosis is characterized by a small
+granular kidney in which fibrous changes of a patchy character have
+taken place. These scattered areas are the result of obliterating
+endarteritis of renal arteries here and there with consequent anemia,
+death of cells, and replacement by fibrous tissue. It occurs as part of
+a generalized arteriosclerosis in which the whole arterial system is the
+seat of diffuse (senile) sclerosis. The palpable arteries are usually
+beaded or even encircled with calcareous deposits and the aorta is the
+seat of an extensive nodular and ulcerating sclerosis. The heart is
+usually small, shows extensive fibrous and fatty changes and possibly
+the condition known as "brown atrophy;" the blood pressure is low. Such
+cases do not show any special symptoms. They are anemic, short of breath
+on exertion, have the appearance and show the signs of senility.
+
+In the first group it is, at times, difficult to say whether the kidney
+disease or the arterial disease is the most important. From a clinical
+standpoint the decision is not essential as the end results are much the
+same in both. However, when actual uremic symptoms dominate the picture,
+it becomes evident that the disease of the kidney is the chief feature
+in the causation of the symptoms.
+
+
+=Abdominal or Visceral=
+
+There is an important group of cases to which but little attention has
+been paid until quite recently. This is the abdominal or visceral type
+of arteriosclerosis. It has been stated that arteriosclerosis of the
+splanchnic vessels almost invariably causes high tension. Among others,
+Janeway has shown that general arteriosclerosis without marked disease
+of the splanchnic vessels does not cause as a rule increase of blood
+pressure.
+
+There are cases in which the brunt of the lesion falls upon the
+abdominal vessels. Such cases have been called "angina abdominalis." It
+has been suggested (Harlow Brooks) that this type of arteriosclerosis
+may be determined by constant overloading of the stomach with food,
+especially rich and spiced food. This causes overwork of the special
+arteries connected with digestion and so leads to sclerosis of the
+vessels of the stomach, pancreas, and intestines. Personal habits
+probably influence to great extent the production of this more or less
+=localized= condition.
+
+The organs supplied by the diseased arteries suffer from changes
+analogous to those occurring in general or local malnutrition, such as
+starvation, old age, or local anemias. These changes are atrophy with
+hemachromatosis (brown atrophy) or fatty infiltration and degeneration.
+Following the degenerative changes there result connective tissue growth
+and further limitation of the functionating power of the affected
+organs.
+
+Pain is a more or less constant symptom of visceral sclerosis. In the
+early stages there may be only a sense of oppression, of weight, or of
+actual pressure in the abdomen or pit of the stomach. There may be only
+recurring attacks of violent abdominal pain accompanied by vomiting. In
+some cases symptoms of tenderness in the epigastrium, pains in the
+stomach after eating, vomiting and backache may suggest gastric ulcer.
+There may be dyspnea and a sense of anguish accompanied with a rapid and
+feeble pulse. Hematemesis may make the symptom group even more like
+ulcer of the stomach, and only the course of the disease with the
+failure of rigid ulcer treatment and the substitution of treatment
+directed toward relief of the arterial spasm with resulting betterment,
+enables one to make a diagnosis. The condition may be present for years
+and the symptoms only epigastric tenderness with dizziness and sweating
+on lying down after dinner, as in one of Perutz's patients. The attacks
+are probably due to spasmodic contraction of the sclerosed intestinal
+vessels with a resulting local rise in blood pressure. The pains are
+most probably due to the spasm of the intestinal muscles, and some think
+they are located in the sympathetic and mesenteric plexuses.
+
+This result of arteriosclerosis is not so uncommon, and by keeping this
+cause of obscure abdominal pain in mind we are now and then enabled to
+save a patient from operation.
+
+An autopsy on a case which for many years had attacks of abdominal pain
+and cramp-like attacks, with high blood pressure and heart hypertrophy,
+showed extensive sclerosis of the abdominal aorta, superior mesenteric
+and iliacs. These vessels were calcified. Hypertrophy of the left
+ventricle was found. The kidneys were microscopically normal. There were
+no changes in the ascending aorta but in the descending portion there
+were scattered nodules and small calcified plaques.
+
+The attacks of pain from which this patient suffered for many years, the
+hypertrophy of the left ventricle and the increased blood pressure were
+thought to be directly due to the sclerosis of the abdominal vessels.
+
+
+=Cerebral=
+
+It has been stated that arteriosclerosis is a general disease, yet
+certain systems of vessels may be affected far more than others, and
+indeed there may be marked sclerosis at one part of the body and none
+demonstrable at another part.
+
+In advanced sclerosis there may be one or more of a series of accidents
+due to embolism, thrombosis, or rupture of the vessels. Such conditions
+as transient hemiplegia, monoplegia or aphasia may occur. The attacks
+may come on suddenly and be over in a few minutes; what Allbutt calls
+"Larval apoplexies." They may last from a few hours up to a day, and are
+very characteristic. A patient aged 64 years with pipe stem radials and
+tortuous hard temporals would be lying quietly in bed when suddenly he
+would stiffen, the eyes would become fixed and the breathing cease. In a
+few seconds consciousness returned, the patient would shake himself,
+pass his hand over his brow and ask, "Where am I? Oh, yes, that's all
+right." He had as many as thirty of these attacks in twenty-four hours,
+none of them lasting over one minute. To just what such attacks are due,
+it is hard to say. Some have attributed them to spasm of the smaller
+blood vessels of the brain, but there have never been demonstrated in
+the vessels any constrictor fibers.
+
+There is a well recognized form of dementia caused by arteriosclerosis.
+In general paralysis of the insane and in senile dementia the blood
+vessels are always diseased. Milder grades of psychic disturbances are
+accompanied by such symptoms as mental fatigue, persistent headaches,
+vertigo, memory weakness and fainting. Aphasia, periods of excitement
+and mental confusion occur in some. Later stages are at times
+accompanied by inclination to fabulate, loss of judgment,
+disorientation, narrowing of the external interests, episodes of
+confusion and hallucinatory delirium.
+
+The hemiplegias, monoplegias and paraplegias may occur again and again
+and last for one or two days. Unless there has been rupture of the
+vessels, there is complete recovery as a rule.
+
+In persons who have arteriosclerosis with high tension attacks of
+melancholia are seen. There are at the same time fits of depression,
+insomnia, irritability, fretfulness, and a generally marked change in
+disposition. When the tension is reduced by appropriate treatment these
+symptoms disappear, to recur when the tension again becomes high. On the
+contrary, attacks of mania are accompanied by low blood pressure. The
+dizziness and vertigo in cerebral arteriosclerosis are probably due to
+the stiffness of the vessels which prevents them from following closely
+the variations of pressure produced by position, and thus, at times, the
+brain is deprived of blood and a transient anemia occurs.
+
+Arteriosclerosis of the cerebral vessels is always a serious condition.
+The greatest danger is from rupture of a blood vessel. Another of the
+dangers is gradual occlusion of the arteries bringing about necrosis
+with softening of the brain substance. The latter is more apt to be
+associated with psychic changes, dementia, etc.; the former, with
+hemiplegia. It is curious that a small branch of the Sylvian artery, the
+lenticulo-striate, which supplies the corpus striatum, should be the one
+which most frequently ruptures. Where the motor fibers from the whole
+cortex are gathered together in one compact bundle, a very small
+hemorrhage may and does cause very serious effects. A comparatively
+large hemorrhage in the silent area of the brain may cause few or no
+symptoms.
+
+
+=Spinal=
+
+It is conceivable that arteriosclerosis of the vessels of the spinal
+cord might cause symptoms which would be referred to the areas of the
+cord where the process was most advanced. The lesions would be scattered
+and consequently the symptoms might be protean in character.
+
+True epileptic convulsions dependent on arteriosclerotic changes are
+also seen and are not so uncommon.
+
+This is on the whole a rare condition, much less common than
+arteriosclerosis of the cerebral vessels. Collins and Zabriskie report
+the following typical case:
+
+ "H., a fireman, fifty-one years old, was in ordinary good health
+ until toward the end of 1902. At that time he noticed that his legs
+ were growing weak and that they tired easily. Later he complained of
+ a jerking sensation in different parts of the lower extremities and
+ at times of sharp pain, which might last from several minutes to two
+ or three hours. The legs were the seat of a heavy, unwieldy
+ sensation, but there was no numbness or other paresthesia. About the
+ same time he began to have difficulty in holding the urine, a
+ symptom which steadily increased in severity. These symptoms
+ continued until March, 1903, i. e., for three months, then he
+ awakened one morning to find that he was unable to stand or walk,
+ and the sphincters of the bowels and bladder relaxed. There was no
+ complaint of pain in the back or legs, no difficulty in moving the
+ arms, in swallowing or in speaking. He says he was able to tell when
+ his lower extremities were touched and he could feel the bed and
+ clothes. He was admitted to the City Hospital three weeks later and
+ the following record was made on April 21, 1903.
+
+ "The patient was a frail, emaciated man of medium height, who had
+ the appearance of being 55-60 years of age. He was unable to stand
+ or walk. When he was lying, he could flex the thigh and the legs
+ slowly and feebly. There was slight atrophy of the anterior and
+ inner muscles, more of the left than of the right side. The knee
+ jerks and ankle jerks were absent. Irritation of the soles caused
+ quite a typical Babinski phenomenon. The patient had fair strength
+ in the upper extremities, but the arms tired very soon, he said. The
+ grip was moderate and alike in each hand. The motility of the face,
+ head, and neck was not noticeably impaired. There was no difficulty
+ in swallowing, and articulation was not defective. Tactile
+ sensibility was slightly disordered in the lower extremities,
+ although he could feel contact of the finger, the point of a pin,
+ and the like. Sensibility was not so acute as normal; there was a
+ quantitative diminution. Sensory perception was not delayed. There
+ was a distinct zone of slight hyperesthesia about as wide as the
+ hand above the femoral trochanters. Above that, sensibility was
+ normal. There was no discernible impairment of thermal sensibility.
+ No part of the body was particularly tender on pressure. A bedsore
+ existed over the sacrum, and there was excoriation of the genitals
+ from constant dribbling of urine.
+
+ "Examination of the chest showed shallow respiratory movements. The
+ heart was regular, weak, there were no murmurs, the second sound was
+ accentuated. Examination of the abdomen showed that the liver and
+ spleen were palpable, but were not enlarged. The abdominal reflexes,
+ both upper and lower, were sluggish. The patient was slow of speech,
+ likewise apparently of thought. He did not seem to show an adequate
+ interest in his condition, still he was fully oriented and seemed to
+ have a fair memory. His mental reflex was slow. There were
+ indications in the peripheral blood vessels and heart of a moderate
+ degree of general arteriosclerosis. The peripheral vessels such as
+ the radial, were palpable, the walls thickened, the blood pressure
+ increased.
+
+ "The patient did not complain of pain while he was in the hospital,
+ a period of four weeks, nor was there any particular change in the
+ patient's symptoms, subjective and objective, during this time. His
+ mental state remained clear until forty-eight hours before death,
+ when he became sleepy, stuporous, and comatose, dying apparently of
+ cardiac weakness, which had set in simultaneously with the clouding
+ of consciousness."
+
+ At autopsy, except for a few small hemorrhages in the posterior
+ horns of the lower dorsal segments on the right side and a similar
+ condition of the left anterior horns, there was nothing noticed. On
+ microscopic examination, there was found widespread sclerosis of the
+ vessels of the cord to a marked degree with only slight thickening
+ of the vessels of the brain. There were secondary degenerations of
+ ascending and descending type particularly marked at the ninth
+ dorsal segment. They included portions of all the tracts, the
+ pyramidal tract as well. The symptoms in brief were: (1) weakness
+ and easily induced fatigue of the legs; (2) peculiar sensations in
+ the lower extremities, described as jerky, numbness, heaviness, and
+ occasionally sharp pain; (3) progressive incontinence of urine; (4)
+ progressive paraplegia.
+
+Since one of the chief manifestations of syphilis is sclerosis of the
+arteries, neurologic cases characterized by irregular symptoms and signs
+which can not be placed in any of the definite system disease groups,
+are possibly due to irregularly scattered areas of sclerosis throughout
+the spinal cord caused by obliterating arteritis. Such cases are not so
+very uncommon. Several have come under my observation. Further studies
+of the spinal cords of these cases at autopsy are necessary before a
+final opinion can be given as to their dependence on arteriosclerosis of
+the spinal vessels.
+
+
+=Local or Peripheral=
+
+When the arteriosclerosis in the peripheral arteries reaches a stage
+where endarteritis obliterans supervenes, there is usually no chance for
+a compensatory or collateral circulation to be established. The area
+supplied by the vessel undergoes dry gangrene. A portion of a toe or
+finger or a whole foot or hand may shrivel up. It is more common to see
+the spontaneous amputation take place in the lower extremities. The same
+effect may be produced by the plugging of a vessel with a thrombus.
+There may be much pain connected with the sudden blocking, whereas the
+gradual obliteration of the blood supply of a toe or foot is not as a
+rule at all painful. The condition is at times revealed more or less
+accidentally when a patient injures his toe or foot and discovers that
+there is no sensation in the part and that the wound instead of healing
+is inclined to grow larger.
+
+Other interesting vasomotor phenomena are frequently connected with
+arteriosclerosis. Such a one is the curious condition known as Raynaud's
+disease, a vascular disorder which is divided into three grades of
+intensity: (1) local syncope, (2) local asphyxia, (3) local or
+symmetrical gangrene. This is not the place to describe this condition
+except to say that the condition called "dead fingers" is the most
+characteristic feature of the first stage. Chilblains represent the
+mildest grade of the second stage. The parts are intensely congested and
+there may be excruciating pain. Any one who has ever had chilblains
+knows how painful they can be. The general health is not impaired as a
+rule, although the attacks are apt to come on when the person is run
+down. The third stage may vary from a very mild grade, with only small
+necrotic areas at the tips of the fingers, to extensive multiple
+gangrene.
+
+Another and very rare condition in which chronic endarteritis was the
+only constant finding is the disease described by S. Weir Mitchell and
+called by him erythromelalgia (red neuralgia). This is "A chronic
+disease in which a part or parts--usually one or more extremities--suffer
+with pain, flushing, and local fever, made far worse if the parts hang
+down." (Weir Mitchell.)
+
+Probably the most frequently seen result of arteriosclerosis in the leg
+arteries is the remarkable condition, first described by Charcot, known
+as intermittent claudication. Persons the subject of this disease are
+able to walk if they go slowly. If, however, any attempt be made to
+hurry the step, there results total disability accompanied at times by
+considerable cramp-like pain. The condition is much more prone to occur
+in men than in women, and Hebrews seem more frequently affected. The
+cause is most probably to be sought in the anemia which results from the
+narrowing of the channels through which the blood reaches the part. The
+stiff, much narrowed arteries allow sufficient blood to pass along for
+the nutrition of the part at rest or in quiet motion. Just as soon as
+more violent exercise is taken, calling for more blood, an ischemia of
+the part supervenes, for the stiff vessels can not accommodate
+themselves to changes in the necessary vascularity of the part. A rest
+brings about a gradual return of blood and the function of the part is
+restored. Pulsation may be totally absent in the dorsal arteries of the
+feet and when the legs are allowed to hang down there is apt to be deep
+congestion.
+
+In this connection a curious case reported by Parkes Weber will not be
+out of place. The patient, a male, aged 42 years, complained of
+cramp-like pains in the sole of the left foot and calf of the leg
+occurring after walking for a few minutes and obliging him to rest
+frequently. When the legs were allowed to hang over the side of the bed,
+the distal portion of the left foot became red and congested looking.
+No pulsation could be felt in the dorsal artery of the left foot or in
+the posterior tibial artery. There was no evidence of cardiovascular or
+other disease. An ulcer on the little toe had slowly healed, but
+cramp-like muscular pains still occurred on walking. The disease had
+lasted about five years without the appearance of gangrene.
+
+Weber calls this case one of arteritis obliterans with intermittent
+claudication.
+
+
+=Pulmonary Artery=
+
+In the symptomatology of sclerosis of the pulmonary artery the clinical
+signs and symptoms are mostly referable to the obliterating endarteritis
+of the smaller vessels, while the physical signs are more apt to reveal
+the involvement of the main trunk. A history of severe infection in the
+past is frequent, especially smallpox, and accompanying aortic sclerosis
+with insufficiency of the mitral valve or stenosis of this valve is the
+rule. Striking cyanosis is an early symptom, while there is little if
+any dyspnea and edema. Intermittent dyspragia is common. There seems to
+be no tendency to clubbed fingers. Repeated hemorrhages from the lungs
+without the formation of infarcts may occur. There is usually an area of
+dullness at the upper left margin of the sternum and nearby parts,
+sensitive to pressure and to percussion, and the heart dullness extends
+unusually far towards the right. The diagnosis of the right ventricular
+hypertrophy may be substantiated by a fluoroscopic examination.
+
+
+
+
+CHAPTER X
+
+DIAGNOSIS
+
+
+=Early Diagnosis=
+
+Arteriosclerosis is essentially a disease of middle life and old age. It
+is not unusual, however, to find evidences of the disease in persons in
+the third decade and even in the second decade. Hereditary influences
+play a most important role, syphilis and the abuse of alcohol in the
+family history are particularly momentous. The recognition of the early
+changes in the arteries among young persons depends largely upon how
+carefully these changes are looked for. The difference in the point of
+view of one man who finds many cases in the comparatively young, and
+another man who rarely finds such changes early in life, at times,
+depends upon the acuity of perception and observation and not upon the
+fact that one man has had a series of unusually young arteriosclerotic
+subjects. The diagnosis of arteriosclerosis may be so easily made that
+the tyro could not fail to make it. It is, however, the purpose of this
+volume to lay stress on the earliest possible diagnosis and, if
+possible, to point out how the diagnosis may be arrived at. It is
+obviously much to the advantage of the patient to know that certain
+changes are beginning in his arteries, which, if allowed to go on, will
+inevitably lead to one or more of the symptom groups described in the
+preceding chapters.
+
+The combination of (1) hypertrophied heart, (2) increased blood
+pressure, (3) palpable arteries, and (4) ringing, accentuated second
+sound at the aortic cartilage is, in reality, the picture of advanced
+arteriosclerosis. If the individual is in good condition much may be
+done by judicious advice and treatment to ward off complications and
+prolong life with a considerable degree of comfort. But we should not
+wait until such signs are found before making a diagnosis and
+instituting treatment. As in all forms of chronic disease the early
+diagnosis is all important.
+
+The history of the case is the first essential. Often a careful inquiry
+into the personal habits of a patient, with the record of all the
+preceding infectious diseases will give us valuable information and may
+be the means of directing the attention at once to the possible true
+condition. Particularly must we inquire into the family history of gout
+and rheumatism. An individual who comes of gouty stock is certainly more
+prone to arterial degeneration than one who can show a healthy heredity.
+Alcoholism in the family also is of importance because of the fact that
+the children of alcoholics start in life with a poor quality of tissue,
+and conditions that would not affect a man from healthy stock might
+cause early degeneration of arterial tissue in one of bad ancestry.
+
+What infectious diseases has the patient had? Even the exanthemata may
+cause degenerations in the arteries, but, as has been shown, such
+lesions probably heal completely with no resulting damage to the vessel.
+Should the patient have passed through a long siege of typhoid fever the
+problem is quite different. Here (vide supra) (Thayer), the palpable
+arteries do appear to be sclerosed permanently. Probably the length of
+time that the toxin has had a chance to act determines the permanent
+damage to the vessel wall. More potent than all other diseases to cause
+early arteriosclerosis is syphilis, and hence very careful inquiry
+should be made in regard to the possibility of infection with this
+virus. Not only the fact of actual infection but the duration and
+thoroughness of treatment are important matters for the physician to
+know.
+
+What is the patient's occupation? Has he been an athlete, particularly
+an oarsman? Has he been under any severe, prolonged, mental strain? Is
+he a laborer? If so, in what form of manual labor is he engaged? Such
+questions as these should never be overlooked, as they form the
+foundation stones of an accurate diagnosis, and early, accurate
+diagnosis, we repeat, is essential to successful therapy.
+
+We have called attention to the factor of sustained high pressure in the
+production of arteriosclerosis. Constant overstretching of the vessels
+leads to efforts of the body to increase the strength of the part or
+parts. The material which is used to strengthen the weakened walls has a
+higher elastic resistance than muscle and elastic tissue, but a lower
+limit of elasticity, and is none other than the familiar connective
+tissue. In athletes, laborers, brain workers who are under constant
+mental strain, and in those whose calling brings them into contact with
+such poisons as lead, there is every factor necessary for the production
+of high tension and consequently of arteriosclerosis.
+
+Another question in regard to personal habits is how much tobacco does
+the patient use and in what form does he use it? Our experience is that
+the cigar smoker is more prone to present the symptoms of
+arteriosclerosis than the cigarette smoker, the pipe smoker, or the one
+who chews the tobacco. A very irritable heart results not infrequently
+from cigarette smoking but such is almost always found in young men in
+whom the lesions of arteriosclerosis are exceedingly rare. The
+probabilities are that the arteriosclerosis in cigar smoking results
+from the slowly acting poison which causes a rapid heart rate with an
+increase of pressure.
+
+Last but not least, and perhaps the most important question is, has the
+patient been a heavy eater? This I believe to be a potent cause of
+splanchnic arteriosclerosis with the resulting indigestion, cramp-like
+attacks, high blood pressure, etc. In a joking manner we are accustomed
+to remark, "Overeating is the curse of the American people." There is,
+however, much truth in that sentence. Osler, than whom there is no
+keener observer, states that he is more and more impressed with the fact
+that overloading the stomach with rich or heavy or spiced foods is today
+one of the first causes of arterial degeneration. It stands to reason
+that this is true. We know that organs exposed constantly to hard work
+undergo hypertrophy, and that the blood tension in those organs is high.
+Blood tension is, after all, dependent on capillary resistance, and if
+the capillaries are distended with blood, the resistance is great. The
+digestive organs can be no exception to this rule. Increased work means
+an increase of blood. This inevitably causes distension of the
+capillaries with stretching of the arteries and consequent damage to the
+walls. Once arteriosclerosis is present a vicious circle is established.
+
+A man about forty-five consults us and says that he has noticed recently
+that he gets out of breath easily; in tying his shoes he experiences
+some dizziness. He finds that he has palpitation of the heart and
+possibly pain over the precordial region now and then. He notices also
+that he is irritable, that is, his family tell him he is, and he notices
+that things that formerly did not annoy him, now are almost hateful to
+him. On examination, one finds a palpable radial, a somewhat
+hypertrophied heart and slightly accentuated second aortic sound. The
+blood pressure may be high. The urine may or may not reveal any
+abnormalities. Not infrequently, although no albumin may be found, there
+are hyaline casts. Such a case of arteriosclerosis is evidently not to
+be regarded as early. Then the question arises, How are we to recognize
+early arteriosclerosis? I do not believe that the solution of this
+problem lies entirely in the hands of the physician. Some men are
+fortunate enough to come up for an examination for life insurance before
+an observant doctor who recognizes the palpable artery, makes out the
+beginning heart hypertrophy and the slightly accentuated second aortic
+sound. The patient will tell you that he never felt better in his life.
+He gets up at seven, works all day, plays golf, drinks his three to six
+whiskies, and is proud of his physical development. But the great mass
+of people are not fortunate from this standpoint. They do not seek the
+advice of the physician until they are stretched out in bed. They boast
+of the fact that for twenty years they have never had a doctor. One may
+well say that it is a problem how to reach such persons. It seems to me
+that there can be but one way to do this. The people must be taught that
+the duty of a physician is just as much to keep them in health as it is
+to bring them back to health when they are ill. To that end people
+should be taught that at least twice a year they should be carefully
+examined. I do not mean that the patient should present himself to the
+doctor and, after a few questions the doctor say cheerfully, "You are
+all right." The patient should be systematically examined. That means a
+removal of the clothing and examination on the bare skin. Such
+cooperation on the part of patient and doctor would save the patient
+years of active life and make of the doctor, what his position entitles
+him to be, the benefactor to the community. Too often careless work on
+the physician's part lulls the patient into a false sense of security
+and he wakes up too late to find that he has wasted months or years of
+life. Early diagnosis of arteriosclerosis is only possible in
+exceptional cases unless people present themselves to the physician with
+the thought in mind that he is the guardian of health as well as the
+healer.
+
+There are patients who go to the ophthalmologist for failing vision.
+Physically they feel quite well. They have been heavy eaters, hard
+workers, men and women who have been under great mental strain. On
+examination of the fundus of the eye there is found slight tortuosity of
+the vessels with possibly areas of degeneration in the retina. A careful
+physical examination will usually reveal the signs of arteriosclerosis
+elsewhere. We have mentioned frequently high tension as an early sign.
+This must be taken with somewhat of a reservation, for this reason: not
+infrequently a persistent high tension is the earliest sign of chronic
+nephritis. The arteries may be pipe stem in character and the heart
+small and flabby. However, if one watches for the palpably thickened
+superficial arteries (always bearing in mind the normal palpability as
+age advances) and the high tension, he can not go far wrong in his
+treatment whether the case is one of chronic nephritis or of
+arteriosclerosis.
+
+There is also this to bear in mind. Arteriosclerosis may be marked in
+some vessels and so slight in the peripheral vessels that it can not
+with certainty be made out. But when the radials are sclerosed, it is
+usually the case that similar changes exist in other parts. Then too,
+there may be marked changes at the root of the aorta leading to
+sclerosis of the coronary vessels alone, and the first intimation that
+the patient or any one else has that there is disease, may be an attack
+of angina pectoris. Except for symptoms on the part of the heart there
+is no way to make the diagnosis of sclerosis of the coronary arteries.
+
+
+=Differential Diagnosis=
+
+In arriving at a diagnosis, when the question is whether or not
+arteriosclerosis is the main etiologic factor, the most important fact
+to know is the age of the patient. Other points that have been dwelt on
+fully must of necessity also be borne in mind.
+
+Possibly the chief conditions that may be confused with some of the
+results of arteriosclerosis are pseudo angina pectoris which may be
+mistaken for true angina pectoris, and ulcer of the stomach,
+appendicitis (?) or other inflammatory abdominal condition which may be
+mistaken for angina abdominalis.
+
+Differential tables are sometimes of value in fixing the chief points of
+difference graphically.
+
+ =Pseudo angina pectoris=.
+
+ Etiology rather certain; hysteria, neurasthenia, toxic agents, and
+ reflex irritations.
+
+ No age is exempt. Usually in young people, chiefly females.
+
+ Paroxysms of pain occur spontaneously, are periodic and often
+ nocturnal.
+
+ Pain, while severe, is diffuse and sensation is of distension of
+ heart. No sense of real anguish.
+
+ Duration may be an hour or more.
+
+ Restlessness and emotional symptoms of causative conditions are
+ prominent.
+
+ Usually no increase in arterial tension.
+
+ Prognosis favorable.
+
+
+ =True angina pectoris=.
+
+ Etiology not certain but almost always associated with
+ arteriosclerosis of the coronary arteries and also aortic
+ regurgitation.
+
+ Age is important factor. Rare before forty, and males usually
+ affected.
+
+ Paroxysms brought on by overexertions or excessive mental emotion.
+ Rarely periodic.
+
+ Intense pain, radiating down arm; heart felt as in a vise. Sense of
+ anguish and impending dissolution.
+
+ Duration from few seconds to several minutes.
+
+ Silent and fixed attitude, rigidity rather than restlessness.
+
+ Arterial tension is as a rule increased.
+
+ Prognosis most unfavorable.
+
+In differentiating between ulcer of the stomach and angina abdominalis
+the following points may be of service:
+
+
+ =Ulcer=.
+
+ Occurs as a rule in young persons, more often females.
+
+ Pain of boring character increased by food and by certain positions
+ with food in stomach. Felt through to left of spine.
+
+ Occult blood found in stools.
+
+ Considerable anemia apt to be present.
+
+ Arterial tension usually low.
+
+
+ =Angina abdominalis=.
+
+ Only occurs in adults over forty who have been heavy eaters and
+ drinkers, mostly males.
+
+ Pain cramp-like, diffuse, although more localized in epigastrium.
+ Not necessarily any connection with food.
+
+ No occult blood in stools.
+
+ Anemia more often absent.
+
+ Arterial tension high. (Splanchnic sclerosis.)
+
+
+=Diseases in Which Arteriosclerosis Is Commonly Found=
+
+There are certain more or less chronic diseases in which
+arteriosclerosis is found either as a separate disease or as a result of
+the chronic disease itself, or the sclerosis may be the cause of the
+disease. As examples of the first class are diabetes mellitus and
+cirrhosis of the liver. As examples of the second class are chronic
+nephritis, gout, syphilis, and lead poisoning. Examples of the third
+class have already been fully described. Then certain rare diseases that
+have been briefly described in this chapter, viz.: Raynaud's disease and
+erythromelalgia are frequently associated with demonstrable
+arteriosclerosis.
+
+
+
+
+CHAPTER XI
+
+PROGNOSIS
+
+
+In a disease that presents as many vagaries as arteriosclerosis, it is
+not possible to give a certain prognosis. Unfortunately we do not as a
+rule see the arteriosclerotic until the disease is well advanced, or
+even after some of the more serious complications have taken place. By
+that time the condition is progressive, and while the prognosis is grave
+the individual may live a number of years.
+
+It is fortunate for the arteriosclerotic that mild grades of the disease
+are compatible with a fairly active life. The disease in this stage may
+become arrested and the patient may live many years. Not only in the
+mild grades is this possible. Even patients with advanced sclerosis may
+enjoy good health provided the organs have not been so damaged as to
+render them unfit to perform their functions. The frequency with which
+we see advanced arteriosclerosis at the postmortem table as an
+accidental discovery, attests the truth of the foregoing statement. Yet
+how often does it happen that individuals, apparently in the best of
+health, suddenly succumb to an asthmatic or uremic attack, an apoplexy,
+cessation of the heart beat, or a rupture of the heart due to
+arteriosclerosis!
+
+In order to arrive at an intelligent opinion in regard to prognosis
+certain factors must be taken into consideration, chief of which are:
+the seat of the sclerosis; the probable stage; the existing
+complications; and, last and most important, the patient himself. The
+whole man must be studied and even then our prognosis must be most
+guarded.
+
+It is much more dangerous for the patient when the process is in the
+ascending portion of the arch of the aorta than when it has attacked the
+peripheral arteries. Here, at the root of the aorta, are the openings of
+the coronary arteries and the arteries supplying the brain are close
+by. The coronary arteries here control the situation. When loud murmurs
+are heard at the aortic orifice and the heart is evidently diseased, it
+is useful to divide the endocarditis into two types, the
+arteriosclerotic and the endocarditic. The etiology of the former is
+sclerosis and the prognosis is grave because of the liability, nay the
+probability, that the orifices of the coronary arteries will become
+narrowed. The etiology of the second type is in most cases rheumatic
+fever or some other infectious disease, and the prognosis is far better
+than in the first type. True, the two may be combined. In such a case,
+the prognosis is entirely dependent upon the course of the
+arteriosclerosis.
+
+The involvement of the arteries in the kidneys is of considerable
+importance, for it is usually bilateral and widespread. As a rule, the
+disease makes but slow progress provided that the general condition of
+the patient is good, but at any time from a slight indiscretion or for
+no assignable cause, symptoms of renal insufficiency may appear and may
+rapidly prove fatal.
+
+It must not be thought that because the localization of the
+arteriosclerosis in the peripheral arteries is usually the most
+favorable condition that it is therefore devoid of ill effects. On the
+contrary, very serious, even fatal, results may be brought about by
+interference with the circulation with resultant extensive gangrene of
+the part supplied by the diseased arteries. The amputation of a portion
+of a leg, for instance, may relieve, to some extent, an overburdened
+heart and prove life-saving to the patient, but the neuritic pains are
+not necessarily relieved. The torture from these pains may be
+excruciating.
+
+No stage of the disease is exempt from its particular danger. In the
+early stages of the disease before the artery or arteries have had time
+to become strengthened by proliferation of the connective tissue, there
+is the danger of aneurysm. Later, the very same protective mechanism
+leads to stiffening and narrowing of the arteries and hence to
+increased work on the part of the heart with all of its consequences.
+Thrombosis is favored, and where atheromatous ulcers are formed,
+embolism is to be feared.
+
+As the complications and results of arteriosclerosis come to the front
+every one must be considered by itself and as if it were the true
+disease. There may be a slight apoplectic attack from which the patient
+fully recovers, but the prognosis is now of a grave character, as the
+chances are that another attack may supervene and carry off the subject.
+Yet, after an apoplectic attack, patients have lived for many years.
+Probably the most noted illustration of this is the life of Pasteur. He
+had at forty-six hemiplegia with gradual onset. He recovered with a
+resulting slight limp, did some of his best work after the stroke, and
+lived to be seventy-three years old. Yet the exception but proves the
+rule and the prognosis after one apoplectic stroke should always be
+guarded.
+
+The first attack of cardiac asthma is to be looked upon as the beginning
+of the end. The end may be postponed for some time, but it comes nearer
+with every subsequent attack. One may recover from what appears to be a
+fatal attack of cardiac asthma accompanied by edema of the lungs and
+irregular, intermittent, laboring heart, but the recovery is slow and
+the chances that the next attack will be the fatal one are increased.
+
+The significance of albuminuria is difficult to determine. The kidneys
+secrete albumin under so many conditions that the mere presence of
+albumin in the urine may have but little prognostic value. Many cases
+are seen where there is no demonstrable albumin, and yet the patient may
+suddenly have a cerebral hemorrhage. As a general rule the urine should
+be carefully examined, but not too much stress should be laid on the
+discovery of albumin and casts. It is not always possible to determine
+the extent of the kidney lesion by the urinary examination, yet at any
+time a uremic attack may appear and prove fatal.
+
+After all the most important fact for the patient is not what the
+pathologist finds in his kidneys after he is dead, but what the living
+functional capacity of the kidneys is. This can now be determined in a
+variety of ways as the result of extensive work carried out in quite
+recent years. The simplest method of determining the functional capacity
+of the kidneys is by the injection into the muscles of the back of a
+solution containing 6 mg. of the drug phenolsulphonephthalein in one
+c.c. of fluid. This comes already prepared in ampules, with full
+directions for its employment.[16] Some clinicians use indigo-carmine in
+place of phthalein. The general consensus of opinion is in favor of
+phthalein.
+
+ [16] I have found the small colorimeter made by Hynson, Westcott and
+ Dunning, Baltimore, Mo., costing $5.00, a very practical instrument.
+
+The nephritic test meal carefully worked out by Mosenthal[17] gives much
+valuable information. The determination of the nonprotein nitrogen or
+the creatinin in the blood also reveals the functional capacity of the
+kidneys.[18]
+
+ [17] Mosenthal, H. O.: Arch. Int. Med., 1915, xvi, 733.
+
+ [18] Myers and Lough: Arch. Int. Med., 1915, xvi, 536.
+
+One might say that the appearance of albumin in the urine of an
+arteriosclerotic where it had not been before, is a bad sign, and in
+making a prognosis this must be taken into consideration.
+
+Bleeding from the nose is not infrequently seen in those who have
+arteriosclerosis. It can hardly be called a dangerous symptom as it can
+always be controlled by tampons. There are times when epistaxis is
+decidedly beneficial as it relieves headache, dizziness, and may avert
+the danger of a hemorrhage into the brain substance. It is rare to have
+nose bleed except in cases of high tension in plethoric individuals. My
+experience has been that it has saved me the trouble of bleeding the
+patient. It is always of serious import in that it indicates a high
+degree of tension, but there is scarcely ever any immediate danger from
+the nose bleed itself.
+
+Intestinal hemorrhage is always a grave sign. As has been shown,
+arteriosclerosis of the splanchnic vessels not infrequently occurs, and
+an embolus or thrombus may completely occlude the superior mesenteric
+artery. The chances of the establishment of a collateral circulation are
+small, as the arteries of the intestines are end arteries. Necrosis of
+the part follows, blood is found in the stools, and perforation or
+gangrene, or both, are apt to follow. There may be blocking of small
+branches only, leading to ulceration of the intestine. Under all
+conditions the prognosis is serious.
+
+The general condition of the patient, his build, physical strength,
+powers of recuperation, etc., must be taken into account in giving a
+prognosis. The more powerful the individual, the more favorable, as a
+rule, is the prognosis, with this reservation always in mind, that the
+greater the body development, the greater is the heart hypertrophy, and
+the accidents from high tension must not be overlooked. Many puny
+individuals with stiff, calcified arteries go about with more ease than
+a robust man with thickened arteries only. The differentiation as
+pointed out by Allbutt (page 186), is well to keep in mind in giving a
+prognosis. It can not be too strongly emphasized that it is the whole
+patient that we must consider and not any one system that at the time
+happens to be the seat of greatest trouble, and by its group of symptoms
+dominates the picture.
+
+It is evident from what has been said that an accurate prognosis in
+arteriosclerosis is no easy matter. Were arteriosclerosis a simple
+disease of an acute character there might be grounds for giving a more
+or less definite prognosis. The most that can be said is that
+arteriosclerosis is always a serious disease from the time that symptoms
+begin to make themselves known. The gravity depends altogether on the
+seat of the greatest arterial changes, and is necessarily greater when
+the seat is in the brain than when it is in the legs or arms.
+
+The attitude of the patient himself also determines to a great extent
+the prognosis. Some men, especially those who have always enjoyed good
+health, turn a deaf ear to warnings and instead of ordering their lives
+according to the advice of the physician, persist in going their own way
+in the hope that the luck that has always been with them will continue
+to stand at their elbows. Neither firmness nor pleadings avail with some
+men. The only salve for the conscience of the physician is that he has
+done his best to steer the patient away from the shoals and breakers. In
+others who realize their condition and take advantage of the advice
+given as to the regulation of their lives, the prognosis is generally
+favorable.
+
+To sum up the chapter in a few words, I should say: Always remember that
+the patient is a human being; study his habits and character and mode of
+life; look at him as a whole; take everything into consideration, and
+give always a guarded prognosis.
+
+
+
+
+CHAPTER XII
+
+PROPHYLAXIS
+
+
+Arteriosclerosis comes to almost every one who lives out his allotted
+time of life. As has been noted within, many diseases and many habits of
+life are conducive to the early appearance of arterial degeneration.
+Decay and degeneration of the tissues are necessary concomitants of
+advancing years and none of us can escape growing old. From the period
+of adolescence certain of the tissues are commencing a retrograde
+metamorphosis, and hand in hand with this goes the deposit of fibrous
+tissue which later may become calcified. The arterial tissue is no
+exception to this rule, and we have already shown that certain changes
+normally take place as the individual grows older, changes which are
+arteriosclerotic in type and are quite like those caused in younger
+people by many of the etiologic factors of the disease.
+
+We are absolutely dependent upon the integrity of our hearts and blood
+vessels for the maintenance of activity and span of life. Respiration
+may cease and be carried on artificially for many hours while the heart
+continues to beat. Even the heart has been massaged and the individual
+has been brought back to life after its pulsations have ceased, but such
+cases are few in number. We can not live without the heart beat and the
+prophylaxis of arteriosclerosis consists in the adjustment of our lives
+to our environment, so that we may get the maximum amount of work
+accomplished with the minimum amount of wear and tear on the blood
+vessels.
+
+The struggle for existence is keen. Competition in every profession or
+trade is exceedingly acute, so much so that to rise to the head in any
+branch of human activity requires exceptional powers of mind. Among
+those who are entered in this keen competition, the fittest only can
+survive for any period of time. The weaklings are bound to succumb. A
+scion of healthy stock will stand the wear and tear far better than will
+the progeny of diseased parentage.
+
+It is only necessary to call attention to the part that alcohol,
+syphilis and insanity play in heredity. These have been discussed fully
+in the earlier part of this book.
+
+We live rapidly, burning the candle at both ends. It is not strange that
+so many comparatively young men and women grow old prematurely. While
+heredity is a factor as far as the prophylaxis of arteriosclerosis is
+concerned, of far more importance is the mode of life of the individual.
+Scarcely any of us lead strictly temperate lives. If we do not abuse our
+bodies by excessive eating and drinking and so wear out our splanchnic
+vessels and cause general sclerosis by the high tension thereby induced,
+we abuse our bodies by excessive brain work and worry with all their
+multitudinous evils. The prophylaxis of arteriosclerosis might well be
+labeled, "The plea for a more rational mode of life." Moderation in all
+things is the keynote to health, and to grow old gracefully is an art
+that admits of cultivation. Excesses of any kind, be they mental, moral,
+or physical, tend to wear out the organism.
+
+People habitually eat too much; many drink too much. They throw into the
+vascular system excessive fluid combined frequently with toxic products
+that cause eventually a condition of high arterial tension. It has been
+shown how poisonous substances absorbed from the intestines have some
+influence on the blood pressure. Anything that causes constant increase
+of pressure should be studiously avoided.
+
+Mild exercise is an essential feature of prophylaxis. One may, by
+judicious exercise and diet, make of himself a powerful muscular man
+without, at the same time, raising his average blood pressure. The man
+who goes to excess and continually overburdens his heart, will suffer
+the consequences, for the bill with compound interest will be charged
+against him. It is a great mistake for any one to work incessantly with
+no physical relaxation of any kind, and yet, after all, it is not so
+much physical relaxation that is necessary, as the pursuit of something
+entirely different, so that the mind may be carried into channels other
+than the accustomed routes. Diversification of interests is as a rule
+restful. That is what every man who reaches adult life should aim at.
+Hobbies are sometimes the salvation of men. They may be ridden hard, but
+even then they are helpful in bearing one completely away from daily
+cares and worries. The man who can keep the balance between his mental
+and physical work is the man who will, other things being equal, live
+the longest and enjoy the best health.
+
+Nowadays the trend of medicine is toward prophylaxis. We give the state
+authority to control epidemics so far as it is possible by modern
+measures to control them.
+
+We urge over and over again the value of early diagnosis in all chronic
+diseases, for we know that many of them, and this applies particularly
+to arteriosclerosis, could be prevented from advancing by the
+recognition of the condition and the institution of proper hygienic and
+medicinal treatment.
+
+_It is the patent duty of every physician to instruct the members of his
+clientele in the fundamental rules of health._ Recently the President of
+the American Medical Association, in his address before the 1908
+meeting, urged the dissemination of accurate knowledge concerning
+diseases among the laity. While this may be done by city and state
+boards of health, it seems far better for the modern trained physician
+to work among his own people. With concise information concerning the
+modes of infection and the dangers of waiting until a disease has a firm
+hold before consulting the health mender, people should be able to
+protect themselves from infections and be able to nip chronic processes
+in the bud. But it is difficult to turn the average individual away from
+the habit of having a drug-clerk prescribe a dose of medicine for the
+ailment that troubles him. It is really unfortunate that most of the
+pains and aches and morbid sensations that one has speedily pass away
+with little or no treatment. Herein lies the strength of charlatanism
+and quackery. Unfortunate, yes, for a man can not tell whether the
+trivial complaint from which he suffers is any different from the one
+that was so easily conquered six months ago. But instead of recovering,
+he grows worse. Hope that springs eternal in the human breast, leads him
+to dilly-dally until he at last seeks medical advice, only to find that
+the disease has made such progress that little can be done.
+
+_Instruct the public to consult the doctors twice a year._ The dentists
+have their patients return to them at stated intervals only to see if
+all is well. _How much more rational it would be if men and women past
+the age of forty had a physical examination made twice a year to find
+out if all is well._
+
+The prophylaxis of arteriosclerosis is moderation in all the duties and
+pleasures of life. This in no sense means that a man has to nurse
+himself into neurasthenia for fear that something will happen to him. As
+one grows in years exercise should not be as violent as it was when
+younger, and food should be taken in smaller quantities. Many forms of
+exercise suggest themselves, particularly walking and golf. Walking is a
+much neglected form of exercise which, in these modern days with our
+thousand and one means of locomotion, is becoming almost extinct. There
+is no better form of exercise than graded walking. To strengthen the
+heart selected hill climbing is one of the best therapeutic methods that
+we have. The patient is made to exercise his heart just as he is made to
+exercise his legs, and as with exercise of voluntary muscles comes
+increase in strength, so by fitting exercise may the heart muscle be
+increased in power. A warning should be sounded, however, against over
+exercise. This leads naturally to hypertrophy with all its disastrous
+possibilities. Men who have been athletes when young should guard
+against overeating and lack of exercise as they grow older. Many of the
+factors which favor the development of arteriosclerosis are already
+there, and a sedentary, ordinary life, such as office all day, club in
+afternoon, a few drinks and much rich food, will inevitably lead to
+well-advanced arterial disease.
+
+Karl Marx in his famous Socialistic platform said: "No rights without
+duties; no duties without rights." So we may paraphrase this and say:
+"No brain work without moderate physical exercise in the open air; no
+physical exercise without moderate brain work."
+
+There is yet one other point that is important, the combination of
+concentrated brain work and constant whiskey drinking. This is most
+often seen in men of forty-five to fifty-five, heads of large business
+concerns who habitually take from six to twelve drinks of whiskey daily,
+and with possibly a bottle of wine for dinner. Such men appear ruddy and
+in prime health but, almost invariably, careful examination will reveal
+unmistakable signs of arterial disease. There is usually the enlarged
+heart and pulse of high tension with or without the trace of albumin in
+the urine. The lurking danger of this group of manifestations has so
+impressed the medical directors of several of the large insurance
+companies that a blood pressure reading must be made on all applicants
+over forty years of age. Should high blood pressure be found, the
+premium is increased, as the expectation of life is proportionately
+shorter in such men than in normal persons.
+
+Therefore, let every physician act his part as guardian of health. Only
+in this way is the prophylaxis of arteriosclerosis possible.
+
+
+
+
+CHAPTER XIII
+
+TREATMENT
+
+
+Although it has been rather dogmatically stated (vide supra) that every
+one who reaches old age has arteriosclerosis, it must not be inferred
+that absolutely no exceptions to this rule are found. Cases are known
+where persons of ninety years even had soft arteries, and we have seen
+persons of eighty whose arteries could not be palpated. When infants and
+children are seen with considerable sclerosis, it proves that, after
+all, it is the quality of the tissue even more than the wear and tear,
+that is the determining factor in the production of arteriosclerosis. It
+would be well if those who can not bring healthy progeny into the world
+were to leave this duty to those who can.
+
+In general the treatment of arteriosclerosis is prophylactic and
+symptomatic. In the preceding chapter I had something to say about
+prophylaxis in general; I must again refer to it in detail.
+
+Arteriosclerosis is essentially a chronic progressive disease, and the
+secret of success in the management of it is not to treat the disease or
+the stage of the disease, but to treat the patient who has the disease.
+To infer the stage of the disease from the feeling of the sclerosed
+artery, may lead to serious mistakes. Persons with calcified arteries
+may be perfectly comfortable, while those with only moderate thickening
+may have many severe symptoms. The keynote is individualization. It is
+manifestly absurd to treat the laboring man with his arteriosclerosis as
+one would treat the successful financier. The habits, mode of life,
+every detail, should be studied in every patient if we expect to gain
+the greatest measure of success in the treatment. One may treat fifty
+patients who have typhoid fever by a routine method and all may
+recover. Individualizing, while of great value in the treatment of acute
+diseases, yet is not absolutely essential in order that good results may
+be obtained. Far different is it when treating a disease like
+arteriosclerosis. One who relies on textbook knowledge will find himself
+at a loss to know what to do. Textbooks can only outline, in the
+briefest manner, the average case, and no one ever sees the average book
+case. At the bedside with the patients is the place to learn
+therapeutics as well as diagnosis. All that can be hoped for in
+outlining the treatment of arteriosclerosis is to lay down a few
+principles. The tact, the intuition, the subtle something that makes the
+successful therapeutist, can not be learned from books. So the man who
+treats cases by rule of thumb is a failure from the beginning. There are
+certain general principles that will be our sheet anchors at all times
+and for all cases. The art of varying the application of these
+fundamentals to suit the individual case, is not to be culled from
+printed words.
+
+
+=Hygienic Treatment=
+
+Every man is more or less the arbiter of his own fate. Granted that he
+has good tissue to begin life, his own habits and actions determine his
+span of comfortable existence. No one cares to live after his brain
+begins to fail, and the failing brain is often due to disease of the
+cranial arteries. The hygienic treatment resolves itself into advice in
+regard to prophylaxis.
+
+First and foremost is exercise. It has seemed to us that the revival of
+out-of-door sports is one of the best signs of promise of the
+preservation of a virile, hardy race. That women, as well as men,
+indulge in the lighter forms of out-of-door exercise should bring it
+about that the coming generation will start in life under the most
+advantageous conditions of bodily resistance.
+
+Among all the forms of exercise, golf probably is the best. It is not
+too violent for the middle-aged man, yet it gives the young athlete
+quite enough exercise to tire him. It is played in the open. One is
+compelled to walk up and down in pleasant company, for golf is
+essentially a companionable game, while he reaps the full benefit of the
+invigorating exercise. The blood courses through the muscles and lungs
+more rapidly; the contraction of the skeletal muscles serves to compress
+the veins and so to aid the return of blood to the heart: the lungs are
+rendered hyperemic, deeper and fuller breaths must be taken; oxidation
+is necessarily more rapid, and effete products, which if not completely
+oxidized would possibly act as vasoconstrictors, are oxidized to
+harmless products and eliminated without irritating the excretory
+organs.
+
+Other forms of out-door exercise that can be recommended are tennis,
+canoeing, rowing, fishing, horseback riding, swimming, etc. Tennis is
+the most violent of all the sports mentioned and might readily be
+overdone. Rowing as practiced by the eights at college is undoubtedly
+too violent a form of exercise, and may be productive in later life of
+very grave results. Canoeing is a delightful and invigorating exercise.
+The muscles of the arms, shoulders, and trunk are especially used, the
+leg muscles scarcely at all. Nevertheless, the deep breathing that
+necessarily comes with all chest exercises aerates every portion of the
+lungs, and is of great benefit to the whole body.
+
+Swimming as an exercise has much to recommend it. In this sport all the
+muscles take part and at the same time the chest is broadened and
+deepened.
+
+All these methods of using the muscles to keep oneself in trim, so to
+speak, are part and parcel of the general hygienic mode of life that is
+conducive to a healthy old age. Exercise can be overdone, as eating can
+be overdone. Both are essential and yet both can be the means of
+hastening an individual to a premature grave.
+
+When the arteriosclerosis has advanced so far that it is easily
+recognizable, certain forms of exercise should be absolutely prohibited.
+Such are tennis, rowing and swimming. Horseback riding to be allowed
+must be strictly supervised. At times this may be an exceedingly violent
+exercise. As an out-of-door sport, there is nothing that equals golf.
+The physician, knowing the character of the course, and the length of
+it, can say to his patient that he may play six, nine, twelve, or
+eighteen holes, depending on the patient's condition.
+
+For those who are not able to get out, exercise in the room with the
+windows open must take the place of out-of-door sports. Here the use of
+chest weights is a most excellent means of keeping up the tone of the
+muscles. By adjusting the weights, the exercise may be made light,
+medium, or heavy. Every physician should be familiar with the chest
+weight exercises. They are not as good as open air exercise but they
+undoubtedly have been the means of saving years of life to many patients
+with arterial disease.
+
+There comes a time when all forms of exercise must be prohibited on
+account of the dyspnea, edema, dizziness, etc. It seems unwise to keep
+such a patient in bed, even though the edema be considerable. Once on
+his back in bed he becomes weak, and the danger of edema of the lungs or
+hypostatic congestion of the bases, with subsequent bronchopneumonia, is
+very great.
+
+Such patients may be allowed to sit up in a comfortable chair with the
+legs supported straight out on a stool or other chair. The half
+reclining position is not easy to assume in bed. Considerable ingenuity
+must often be exercised by the physician in making the patient
+comfortable without increasing the symptoms from which the patient
+suffers following the least amount of exercise. Although such persons
+can not exercise actively, they should have passive exercise in the form
+of massage, carefully given, so that no injury is done to the rigid
+vessels. It is possible to rupture a vessel, the walls of which are
+encrusted with lime salts, and full of small aneurysmal dilatations.
+Every patient must be watched carefully and measures instituted for the
+individual.
+
+
+=Balneotherapy=
+
+As a tonic and invigorator, the cold or cool bath (shower or tub), in
+the morning on arising can be highly recommended. It promotes skin
+activity, is a stimulant to the bowels and kidneys and to the general
+circulation, besides being cleansing. We find today that the morning
+bath has become such a necessity to the average American that all new
+hotels are fitted with private baths, and old hotels, in order to get
+patronage, are arranging as many baths connected with sleeping rooms as
+is possible. Our generation assuredly is a ruddy, clean-bodied one. What
+the actual results of this out-door life and frequent bathing will be
+for the race remains to be seen, but one can not but feel that it must
+build up a stronger, more resistant race of people, who not only enjoy
+better health than did their forefathers, but enjoy it longer.
+
+Not every one can stand a cold bath. It is folly to urge it on one to
+whom it is distasteful, or on one who does not feel the comfortable glow
+that should naturally result. For the well, or those with a tendency to
+arteriosclerosis, or those in whose families there have been several
+members who had early arteriosclerosis, such proceedings as recommended
+could not be improved upon. However, for the person who has well
+recognized sclerosis, only warm baths should be advised, and these not
+daily. The water should be at a temperature of 90-95 deg. F. Care should be
+taken that persons sent to spas be cautioned against hot baths. It is
+not inconceivable that the increased force of the heart beat that
+accompanies a hot bath might be sufficient to rupture a small cranial
+vessel. Hence, Turkish and Russian baths should be most unqualifiedly
+condemned. As a matter of fact, persons vary so in their habits with
+regard to bathing that what might suit one person would do another much
+harm.
+
+
+=Personal Habits=
+
+The personal habits of the individual, more than any other factor,
+determine whether or not arteriosclerosis sets in early in his life. The
+man or woman who is moderate in eating and drinking, sees that the
+kidneys are kept in good condition, and attends strictly to regularity
+of the bowels, lays a good basis for the measure of health which is so
+essential for happiness. It has been shown that sclerosis of the
+splanchnic vessels may be due to constant irritation of toxic products
+elaborated in digesting constantly enormous meals. In obstinate
+constipation, many poisons, the nature of which we do not know, are
+absorbed and circulate in the blood. We have not sufficient data to
+prove that constipation favors the production of arteriosclerosis, but
+our impression has been that it does favor it. Constipation can often be
+relieved by a glass of water before breakfast, a regular time to go to
+stool, and abdominal massage or exercises. Some maintain that it is a
+bad habit only, and can be readily overcome. Whatever is done, avoid
+leading the patient into the drug habit, for the last state of the
+patient will be worse than the first. Habits of sleep are not of such
+great importance. Most persons get enough sleep except when under severe
+mental strain. Most adults need from seven to eight hours' sleep,
+although some can do all their work and keep in prime health on five or
+six hours' sleep.
+
+Tobacco has been accused of causing many ills and has been thereby much
+maligned. We can not see that the use of tobacco in any form in
+moderation is harmful to most men. Undoubtedly the blood pressure is
+raised when mild tobacco poisoning occurs, and individual peculiarities
+of reaction to the weed are multitudinous. But to condemn offhand its
+use is the height of folly. There is no reason why the arteriosclerotic
+who has always used tobacco in moderation, should not continue to use
+it, whether he smoke cigarettes, cigars, or pipe. His supply should be
+decreased, but there is no sense in depriving a man of one of the
+solaces of life, unless, as is sometimes the case, abstinence is easier
+for the patient than moderation.
+
+As for alcohol, opinions differ widely.[19] Some see in alcohol one of
+the most frequent causes of arteriosclerosis; others do not believe that
+the part played by alcohol is a serious one, only in conjunction with
+other poisonous substances is it dangerous. Probably unreasoning
+fanaticism has had much to do with the wholesale condemnation of
+alcoholic beverages. The general effect of alcohol is to lower the blood
+pressure by causing marked dilatation of all the vessels of the skin.
+True, the alcohol circulates in the blood, and is broken up in the
+liver, and this organ would seem to bear the brunt of the harm done.
+Alcoholic drinks in moderation, I do not believe have any deleterious
+effect on health. On the contrary, I believe that they may in some cases
+assist digestion and assimilation. Indiscriminate indulgence is to be
+condemned, as is overindulgence in exercise or eating. What may be
+moderate for A, might be excessive for B. Every man is then the arbiter
+of his own fortune and within his own limits can indulge moderately (a
+relative term after all) without fear of doing himself harm. In advanced
+arteriosclerosis it is necessary to decrease the supply of alcohol just
+as it is necessary to cut down the food supply. This must rest entirely
+on the judgment of the physician, who must not act arbitrarily, but must
+have his reasons for every one of his orders.
+
+ [19] Discussion of alcohol at present has value only as it relates
+ to the past. The present is dry. The future is in the lap of the gods.
+
+
+=Dietetic Treatment=
+
+Most persons eat too much. We not only satisfy our hunger, but we
+satisfy our palates, and, instead of putting substantial foodstuffs
+into our stomachs, we frequently take unto ourselves concoctions that
+defy description.
+
+Foodstuffs are composed of one or all of three classes: (1) proteins,
+(2) fats, (3) carbohydrates. As examples of the first are beef and white
+of egg; of the second, the oils, butter, lard; of the third, sugar,
+potato, beet, corn, etc.
+
+The physiologists and chemists have shown us that both endogenous and
+exogenous uric acid in excess will cause a rise of blood pressure, but
+the bodies most concerned in the production of elevated blood pressure
+are the purin bodies, those organic compounds which are formed from
+proteins and represent chemically a step in the oxidation of part of the
+protein molecule to uric acid. Red meat contains more of the substances
+producing purin bodies than any other one common foodstuff, and for this
+reason the excessive meat eater is, _ceteris paribus_, more apt to
+develop arteriosclerosis comparatively early in life.
+
+The fats and carbohydrates contain practically no substances that react
+on the body of the ordinary individual in a deleterious manner during
+their digestion. The extra work that is put on the heart by the
+formation of many new blood vessels in adipose tissue is the only
+harmful effect of overindulgence in these foodstuffs.
+
+It has been found that nitrogen equilibrium can be maintained at a wide
+range of levels. Formerly 135-150 gms. of protein daily were considered
+necessary for a man doing light work. Now it is known that half that
+amount is sufficient to keep one in nitrogenous equilibrium, and to
+enable one to keep his weight. A person at rest requires even less than
+that. One who is engaged in hard physical labor burns up more fuel in
+the muscles, and so must have a larger fuel supply.
+
+Although we habitually eat too much we drink too little water. For those
+who have any form of arterial disease an excess of fluid is harmful, as
+the vessels become filled up and a condition of plethora results, which
+necessarily reacts injuriously on the heart and circulation. The
+drinking of a glass of water during meals is, in the author's opinion,
+good practice. The water must be taken mouthful at a time, and not
+gulped down. If this is done, there results sufficient dilution of the
+solid food to enable the gastric juices successfully and rapidly to
+reach all parts of the meal.
+
+Some are in favor of a rigid milk diet for those who have
+arteriosclerosis. Some men have lived on nothing but milk for several
+years and have not only kept in good health, but have actually gained
+weight and led at the same time active lives. It has been held by others
+that rigid milk diet is positively harmful on account of the relatively
+large quantity of calcium salts that are ingested. This was thought to
+favor the deposition of calcareous material in the walls of the already
+diseased arteries. While possibly there may be some danger of increased
+calcification, the majority of clinicians are in favor of a milk cure
+given at intervals. Thus the patient is made to take three to four
+quarts daily for a period of a month. There is then a gradual return to
+a general diet, exclusive of meat, for several weeks, then another rigid
+milk diet period.
+
+If we are bold enough to follow Metschnikoff in his theories of
+longevity, we might advise resection of the large intestine, on the
+ground that it is an enormous culture tube that produces prodigious
+amounts of poisonous substances which are thrown into the general
+circulation. To combat such a grave (?) condition as the carrying of
+several feet of large intestine, we are recommended to take buttermilk
+or milk soured by means of the _b. acidus lacticus_. Clinical experience
+has taught that in arteriosclerosis buttermilk is of great value,
+whether it be the natural product, or made directly from sweet milk by
+the addition of the bacilli. The latter is a smoother product and has,
+to my mind, a delightful flavor. It may be diluted with Vichy or plain
+soda water. Cases that can not take milk or any other food will often
+take buttermilk, and do well on this restricted diet. From two to four
+quarts daily should be taken. It should be drunk slowly as should milk.
+
+
+=Medicinal=
+
+It has long been thought that the iodides have some specific effect on
+the advancing arteriosclerosis, checking its spread, if not really
+aiding nature to a limited restoration of the diseased arteries. It is
+possible that the eulogies upon the iodides owe their origin to the
+successful treatment of syphilitic arteriosclerosis, in which condition
+these drugs have a specific action. However that may be, there is no
+doubt that the administration of sodium or potassium iodide is good
+therapeutics in cases of arteriosclerosis.
+
+Unfortunately many persons have such irritable stomachs that they can
+not take the iodides, even though they be diluted many times. They may
+be made less irritating by giving them with essence of pepsin. Unless
+the case is syphilitic, it is doubtful whether it is of value to
+increase the dose gradually until a dram or even more is taken three
+times daily after meals. Usually a maximum dose of ten grains seems to
+be quite sufficient. This may be taken three times a day, well diluted,
+for three months. There follows a month's rest, then the treatment is
+resumed for another period of three months, and so on. Either sodium or
+potassium iodide in saturated solution may be given. The sodium salt is
+possibly less irritating, and contains more free iodine than the
+potassium salt, although the latter is more generally used. The
+strontium iodide may also be used.
+
+One sees a patient now and then who can not take the iodides, however
+they may be combined. For such patients one may obtain good results with
+iodopin, sajodin, or other of the preparations put up by reputable
+firms. Personally I have never yet seen a patient who could not take the
+ordinary iodides in some form or other, and I am opposed to ready made
+drugging.
+
+The action of the iodides is to lower the blood pressure, and they are
+of greatest value when the blood pressure is high, and when headache and
+precordial pain are present.
+
+When the case is moderately advanced, very mild doses, gr. 1/2, morning
+and evening, of the thyroid extract may be given. It is generally
+believed that the internal secretion of the thyroid and the adrenal are
+antagonistic. That the thyroid secretion lowers blood pressure in
+certain forms of hypertension is certain, possibly on account of its
+iodine content. Some combinations of iodine and thyroid such as the
+iodothyroidin have been used and have had some measure of success
+attributed to them.
+
+Hypertension does not always demand active measures for its reduction.
+Viewed from the physiologic standpoint, hypertension is but the
+expression of a compensating mechanism which is designed to keep the
+blood moving through narrowed channels. Heart hypertrophy then is
+absolutely essential to the maintenance of life. It has been said that
+the highest blood pressures occur in chronic disease of the kidneys. The
+poisonous substances produced in the kidneys must exert their action
+through absorption into the general blood stream. This toxin may be
+completely eliminated, if we accept as our criterion the reduction of
+tension to normal together with the complete return of the affected
+individual to health. A concrete example is as follows: A man aged 44
+years was brought to the Milwaukee County Hospital in coma. His systolic
+blood pressure was over 280 mm. Hg, diastolic 170 mm., his urine
+contained considerable albumin and many casts. He had general anasarca.
+Venesection was done at once and 300 c.c. blood obtained. Immediately
+following this operation the pressure was 210-150, but within twelve
+hours it was again above 280-170. He was given no medication to reduce
+pressure except that he was freely purged. He was given a steam sweat
+bath daily. Frequent blood pressure readings were taken. Within seven
+days the pressure was 130-86. He had, in the meantime, completely
+recovered from his symptoms. He was kept in the hospital for two weeks
+longer assisting in the work on the ward, and he was discharged with a
+pressure (systolic) between 130 and 136 diastolic 80-84. The treatment
+was rest in bed, free purging, venesection, and sweat baths, simple but
+exceedingly effective.
+
+Should there be actual indications for reducing the blood pressure, I
+must admit that it can not always be done. The majority of cases will do
+well on the sodium nitrite or erythrol tetranitrate. However, these do
+not always lower blood pressure and keep it within normal limits. When a
+man has very high tension we do not wish to reduce it to what it should
+normally be for the age of the patient, as symptoms of collapse might
+set in at any time under such conditions.
+
+Observations made with the sphygmomanometer[20] show that the effect of
+nitroglycerin is transient or of no effect except in doses which are
+relatively enormous (one drop of the one per cent solution given every
+hour). Sodium nitrite may lower the blood pressure but the effects will
+have worn off in two hours. It is the same with erythrol tetranitrate.
+Sodium sulphocyanate in doses of from one to three grains three times a
+day is highly recommended by some. My own experience with it does not
+lead me to believe that it is of any great value in hypertension. It,
+however, may be tried. Benzyl benzoate has been used recently to reduce
+the high blood pressure of hypertension. Macht has reported some
+success. In the author's hands it has been efficacious in a few cases.
+As long as the patient takes the drug the pressure may be slightly
+reduced, but upon the withdrawal of the drug the pressure returns to its
+former level. It is well worth a trial and further experimentation may
+reveal better methods of administration. The dose is from 2 to 6 c.c.
+mixed with water at intervals.
+
+ [20] Miller, Jos. L.: Hypertension and the Value of the Various
+ Methods for Its Reduction. Jour. Am. Med. Assn., 1910, liv, p. 1666.
+
+In the hypertension of the menopause some have had success with large
+doses of corpus luteum extract. As a matter of fact the drug treatment
+of hypertension, when it becomes necessary to treat this condition with
+drugs, has suffered a notable set-back since more careful control has
+been made with the blood pressure instruments. In giving any of the
+depressor drugs their action should be controlled by blood pressure
+measurements, for only in this way can we be sure that the drug is
+exerting its physiological effect and we may expect results. The
+individual reaction to these drugs varies greatly and no rule for dosage
+can be dogmatically laid down. The only successful therapy is rigid
+individualization. This is the keystone to treatment in cases of
+arteriosclerosis and high tension.
+
+It must not be inferred from what has been said that the nitrites are of
+no value. They are of decided value but they have their limitations. The
+most evanescent of these drugs is amyl nitrite. This is put up in the
+form of capsules, or pearls, containing from one to three minims. When
+it is desired to dilate the peripheral vessels suddenly, one or two of
+these capsules are broken in a cloth held to the nose. The effect is
+almost instantaneous. There is flushing of the face and other peripheral
+vessels, particularly near the head, denoting a relaxation and widening
+of the bed of the blood stream, and a consequent decrease in pressure in
+the arteries. These effects are over in a short while. It is only used
+in attacks of cardiac spasm, as in angina pectoris. Nitroglycerin, the
+Spiritus Glonoini of the U. S. P., acts in about the same manner as amyl
+nitrite but the effects last usually a trifle longer. One drop of the
+one per cent solution may be given every hour until physiologic effects
+are produced. It may be given hypodermically. This may be a means of
+reducing pronounced high tension. This drug has been found of benefit
+especially in cases where arteriosclerosis combined with chronic
+nephritis causes cardiac asthma. The other drug which may be of service
+in these conditions, one whose sphere of action is somewhat broader,
+because its effects are more lasting, is sodium nitrite. This is given
+in water in doses of one to three or five grains every four hours. Some
+have objected to the use of this drug, but my experience has made me
+place considerable confidence in its harmlessness, provided that the
+patient is carefully watched. This, however, applies to all of the
+nitrite compounds. My experience with erythrol tetranitrate is not
+large. It may be used in place of sodium nitrite.
+
+For a mild case, one often finds that sweet spirits of niter is
+sufficient to control the pressure and relieve the distressing symptoms,
+and it is undoubtedly the least harmful of all the nitrites. Drugs that
+are of great value, but of which little is noted in textbooks, are
+aconite and veratrum viride. Both of these drugs are well known to be
+marked circulatory depressors. Veratrum viride in my experience should
+be very cautiously used, and never used unless a trained attendant is
+constantly at hand. With regard to aconite I have no such feeling, and a
+mixture of tincture of aconite and spiritus etheris nitrosi may be given
+for several weeks with no fear of doing any harm. Personally, of all the
+drugs mentioned, I prefer the nitrite of sodium or the combination just
+given. They may be advantageously alternated.
+
+My own feeling is that the most successful means of treatment of acute
+high tension is without the use of drugs. The most important measure is
+absolute rest in bed. This often suffices to lower the blood pressure
+and to arrest the symptoms produced by high tension. Venesection I
+believe is also of value. True the arterioles appear to contract almost
+immediately upon the lessened quantity of blood, or there is immediate
+interchange of serum from the tissues which brings the blood volume
+back to the original amount. Whatever happens the pressure is not
+greatly reduced, at times not reduced at all, but often the symptoms are
+relieved. Hot packs or sweat baths assuredly do reduce the pressure in
+many cases. This seems to me to be an exceedingly valuable measure.
+Finally the diet should be nourishing, but very light, not too much
+fluid should be ingested, and the bowels should be freely opened.
+
+With the fibrolysin of Merck, I have had no experience. Some men assert
+that they have had good results from its use, but on the whole the
+evidence is not highly favorable.
+
+Morphine is invaluable. No drug is of such value in the nocturnal
+dyspneic attacks that occur in the late stages of arteriosclerosis when
+the heart or the kidneys are failing. Morphine not only relaxes spasm
+and quiets the cerebral centers, but is an actual heart stimulant under
+such conditions, and should never be withheld, as the danger of the
+patient's becoming addicted to its use is more fanciful than real.
+However, morphine, at times, suppresses the secretion of urine. So that
+if after trial the urine becomes scanty and the edema increases,
+recourse must be had to other drugs. The various hypnotics may be used
+with caution. One which seems to be very useful is adalin.
+
+As heart stimulants, one may use strychnine, spartein, caffein, or
+camphor. In desperate cases, where a rapidly diffusible stimulant is
+needed, a hypodermic syringeful of ether may be given, and repeated in a
+short while.
+
+Several years ago a so-called serum was brought out by Trunecek which
+was said to have a favorable effect on the metabolism of the vessel
+walls. It was given at first hypodermatically or intravenously but the
+former method was painful. It was later stated that given by mouth it
+acted just as well. The results with the Trunecek serum have not come up
+to the expectations that the early favorable reports promised. The
+original serum was composed as follows: NaCl, 4.92 gm.; Na_2SO_4, 0.44
+gm.; Na_2CO_3, 0.21 gm.; K_2SO_4, 0.40 gm.; aqua destil. q. s. ad. 100.0
+c.c. Later this was modified for internal use to the following
+prescription:
+
+ R_{x} Natrii chlor. 10. gm.
+ Natrii sulphat. 1. gm.
+ Natrii carbonat. 0.40 gm.
+ Natrii phosphat. 0.30 gm.
+ Calcii phosphat.
+ Magnesii phosphat. aa. 0.75 gm.
+ M. Ft. cachets No. XIII.
+
+The contents of every cachet corresponds to 15 c.c. of the fluid serum
+or to 150 c.c. of blood serum. The preparation called antisclerosin
+consists of the salts contained in the serum. As to its efficacy, I can
+not judge, as I have never felt that it was worth while to use it.
+Reports of cases in which it has been tried do not speak very highly of
+it.
+
+In the general treatment of arteriosclerosis, there is no one factor of
+more importance than the regular daily bowel movement. Attention to this
+may save the patient much discomfort and even acute attacks of cardiac
+embarrassment. The choice of the purgative is immaterial, with this
+reservation only, that the mild ones, such as cascara, rhubarb, licorice
+powder and the mineral waters, should be thoroughly tried before we
+resort to the more drastic purgatives. Plenolphthalein in 3 to 5 grain
+doses acts remarkably well in some people as a pleasant laxative.
+Agar-agar with or without cascara may be useful.
+
+Liquid paraffin under a variety of names is a most useful and
+efficacious laxative. As its action is purely mechanical it may be taken
+indefinitely without doing harm to the intestinal musculature.
+
+The old Lady Webster dinner pill is an excellent tonic aperient. When
+the heart is embarrassed and edema of the legs and effusion into the
+serous cavities have taken place, then it becomes necessary to use the
+drastic purgatives that cause a number of watery movements. Epsom salts
+given in concentrated form, elaterin gr. 1-12, the compound cathartic
+pill, blue mass and scammony, or even croton oil may be used. Since the
+observation of a greatly congested intestine from a patient who had been
+given croton oil, I have ceased to use this purgative, and I doubt much
+whether its use is ever justifiable in these cases.
+
+The management of the ordinary case of arteriosclerosis resolves itself
+into a careful hygienic and dietetic regime with the addition of the
+iodides, aconite, or the nitrites. A diet consisting of very little
+meat, alcohol in moderation or even absolutely prohibited, and not too
+much fluid should be prescribed. Condiments and spices should also be
+used sparingly. Cold baths, shower baths, cold and hot sheets
+alternating, are of great benefit in assisting the heart to do its best
+work by making the large capillary area of the skin more permeable. It
+is not true that such baths raise the blood pressure so markedly.
+Certain acts, as sneezing, violent coughing, etc., increase the blood
+pressure much more than judicious bathing.
+
+
+=Symptomatic Treatment=
+
+The fact that arteriosclerosis really loses much of its own identity
+and, in later stages, becomes merged with the symptomatology of the
+diseases of various organs, as the kidney, brain, heart, compels us, for
+completeness' sake, to say a few words about the treatment of these
+complications.
+
+One of the results of arteriosclerosis of the coronary arteries, angina
+pectoris, demands prompt treatment. In the acute attack, the chief
+object is to relieve the spasm and pain. Pearls of amyl nitrite should
+be inhaled, and morphine sulphate with atropine sulphate given
+hypodermatically at the very earliest moment. It is senseless to
+withhold morphine. The only possible reason for withholding it would be
+uncertainty as to the diagnosis. It is probably better to err on the
+safe side, and should the case prove to be one of pseudo angina, in the
+next attack sterile water can be given instead of the morphine and
+atropine.
+
+When a patient is seen in the condition of broken compensation with the
+much dilated heart, anasarca, dyspnea and suppression of urine, there is
+no better practice than venesection. Especially is this valuable when
+the tension is still fairly high and the individual is robust. Following
+the abstraction of six to eight ounces of blood (300-500 c.c.)[21] the
+whole picture changes, so that a man who a short while before was
+apparently at death's door, notices his surroundings and takes an
+interest again in life. This should be followed up with thorough
+purgation, and cardiac stimulants should be ordered. In such cases
+digitalis is useful, but its action is never so striking as in cases of
+this general character due to uncompensated valvular disease. It must be
+remembered that in arteriosclerosis the changes in the myocardium must
+be of a considerable grade for the heart to give away. Therefore,
+digitalis can not be expected to act on a diseased muscle as it acts on
+a comparatively healthy muscle. It is only in such cases of broken
+compensation that digitalis should ever be used.
+
+ [21] I have taken as much as 1700 c.c. from a large man. He
+ recovered and went back to work.
+
+Digitalis is not a general vasoconstrictor as used to be taught. Its
+action on the kidney is actually a vasodilator one. And in its action on
+the heart the digitonin dilates the coronary arteries, according to
+Macht, while the digitoxin acts on the heart muscle. Overdosing with
+digitalis has produced partial heart block in many cases. It is
+absolutely contraindicated in Stokes-Adams syndrome.
+
+There are, however, some cases, especially those with transudations,
+when digitalis may be carefully tried even though high tension be
+present. It is sometimes of advantage to combine digitalis with the
+nitrites although they are said to be physiologically incompatible.
+
+Still another drug, that is of great value in conditions such as have
+been described, is diuretin. This may be given in capsule or tablets,
+grs. x. three times daily. There is only one caution to express in the
+use of this drug. It should not be given when the kidneys are the seat
+of chronic inflammatory changes; in fact, actual harm may be done by
+administering the drug under such conditions.
+
+The same is true even to a greater extent with theocin. This is a
+powerful diuretic. If given by mouth it should be well diluted as it is
+most irritating to the stomach. It is best given intravenously in doses
+of two and a half to three grains dissolved in five to six cubic
+centimeters of distilled water. One must be reasonably sure that the
+kidneys are not the subject of chronic disease and are functionally,
+therefore, below par. The intravenous dose should not be given oftener
+than once in four days.
+
+For the pain in aneurysm, nothing (except, of course, morphine) is so
+valuable as iodide of potassium. Patients who are suffering agony, when
+put to bed and given KI grs. x. three times a day, soon lose all the
+distressing symptoms. This applies particularly to aneurysms of the arch
+of the aorta.
+
+When the sclerosis has affected the cerebral arteries to such an extent
+that symptoms result, the case is, as a rule, exceedingly grave. Not
+much can be done except to relieve the headaches and keep down the blood
+pressure, if this is high, by means of rest in bed, the iodides,
+aconite, or the nitrites. The cases of transient monoplegias or
+hemiplegias can be much relieved by careful hygienic measures and
+judicious administration of drugs. Much ingenuity is sometimes required
+to overcome the idiosyncrasies of patients, but care and patience will
+succeed in surmounting all such difficulties.
+
+The treatment of intermittent claudication is the treatment of
+arteriosclerosis in general. Sometimes the circulation in the affected
+leg or legs is much helped by daily warm foot baths. Light massage might
+be tried and the galvanic current may be used once or twice daily.
+
+There are a few distressing symptoms that occur usually late in the
+disease, when complications have already occurred, which frequently
+baffle the therapeutic skill of the physician. The chief of
+these--insomnia, dyspnea, and headache--may not be late manifestations,
+but insomnia and headache are frequently associated with the moderately
+advanced stages of arteriosclerosis. At times all the symptoms seem to
+be due to the high tension, the relief of which causes them to
+disappear. There are, unfortunately, times when high tension is not
+responsible for the headache and insomnia. Under these circumstances
+such drugs as trional, veronal, amylene hydrate, ammonol, etc., may be
+tried until one is found which produces sleep. For the headaches,
+phenacetin, alone or in combination with caffein and bromide of sodium,
+may be tried. Acetanilid, cautiously used, is at times of value. There
+have been cases of arteriosclerosis with low blood pressure, accompanied
+by severe headaches, that have been relieved by ergot. Codeine should be
+used with care, and morphine only as a very last resource.
+
+Great care must always be exercised in giving drugs that depress the
+circulation, for it is easily conceivable that more harm than good can
+come from injudicious drugging.
+
+
+
+
+CHAPTER XIV
+
+ARTERIOSCLEROSIS IN ITS RELATION TO LIFE INSURANCE
+
+
+The value of the early recognition of cases of arteriosclerosis and
+hypertension has been spoken of within, but it needs to be further
+emphasized. There is perhaps no class among physicians to whom is
+afforded a better opportunity of seeing early cases than the medical
+examiners of life insurance companies.
+
+The relationship between a patient and the physician whom he consults,
+and the applicant for life insurance and the examiner are diametrically
+opposite. In the former the patient desires to conceal nothing and the
+physician is called upon to diagnose and treat disease. In the latter
+the applicant, a presumably healthy person, may have much to conceal and
+the examiner is there to pass upon the state of health. The question is
+this--"Is the applicant now in good health?" It becomes then of vital
+importance for the examiner to be able to detect among other abnormal
+conditions the incipient signs of arteriosclerosis and of hypertension.
+Parenthetically it may be stated that arteriosclerosis and hypertension
+are not one and the same disease as has been so frequently insisted upon
+within; the former may occur without the latter but the latter can not
+from its very nature be present for long without arterial thickening
+supervening. It is necessary in discussing the question here to group
+the two conditions together in order to prevent needless repetition.
+
+Such a case as the following is common. A successful business man of
+forty-four years was brought to me by an agent in 1905 for examination.
+The man was six feet tall, weighed 218 pounds, had a ruddy color and
+looked to be the picture of health. He was not strictly intemperate, he
+never became intoxicated, but every day he drank three or four whiskies
+and often he had a bottle of wine for dinner in the evening. When he was
+examined his pulse was of good quality and owing to the fleshiness of
+the wrist it was difficult to say positively whether the radial artery
+was sclerosed or not. In the heart no murmurs were heard, and it was
+difficult to be sure that the left ventricle was enlarged. There was,
+however, a slight but definite accentuation of the second sound at the
+aortic cartilage which might readily have been overlooked had the
+patient not been stripped and a careful examination made with the
+stethoscope. Upon taking the blood pressure it was found to be from
+170-175 mm. of Hg. The urine specimen examined at the visit was normal,
+no casts were found. The applicant was seen at his home and the blood
+pressure measured. It was again the same. He was seen a third time and
+practically the same systolic blood pressure was found. Under protests
+from all the agency staff the man was declined. Two years later he died
+of apoplexy. The man was angry at being refused. Instead of looking the
+matter squarely in the face he thrust aside the idea that there was
+anything the matter with him. He had never had one ill day in his life,
+his forebears had lived to ripe old age, and he was sure that he knew
+more about himself than the examiner.
+
+Had this applicant showed a sense of reasonableness he should have been
+grateful to the doctor for calling his attention to a condition which
+surely would sooner or later prove either fatal itself or lead to some
+fatal lesion. It was learned that this man had gone directly to his
+family physician who laughed at such nonsense as had been told the (now)
+patient by the examiner.
+
+Another illustration of a slightly different type of case is afforded in
+the following history.
+
+A man of fifty years of age, five feet ten in height and 164 lbs. in
+weight, was brought for examination. In his youth there was a history
+of a mild attack of scarlet fever. He was almost a total abstainer,
+rarely taking liquor in any form. Physically he appeared to be an
+excellent risk. However, on examining the heart it was found that there
+was slight hypertrophy with an accentuated second aortic sound at the
+base, and the blood pressure was 180 mm. of Hg. Some sclerosis of the
+radial arteries was found. One company had refused him on account of
+albumin in the urine. There was none in the first specimen which was
+passed while in the office. The specific gravity was 1014. A morning
+specimen was obtained and contained a trace of albumin. Several
+specimens were then examined. Some contained albumin, some had no
+albumin content. The man was declined; no protests from the agent as
+albumin had been found. There was something tangible in that. Had the
+applicant been refused on account of his high tension, sclerosis of the
+radials, and slightly enlarged heart there would undoubtedly have been
+protests. And yet an applicant revealing such a state of the
+cardiovascular system without albumin in the urine should unhesitatingly
+be declined. Attention has been called to hypertension as an early, and
+some think an invariable, sign of chronic nephritis. My own experience
+has confirmed me in the belief that in hypertension the kidneys are
+often the seat of chronic interstitial changes. Careful palpation of the
+radial and brachial arteries will in every case reveal more or less
+thickening.
+
+There is yet another group of cases which the examiner sees as healthy
+subjects, namely those cases of sclerosis of the peripheral arteries
+without sclerosis of the aorta and without high tension. In such cases
+the radials, brachials, temporals and other superficial arteries are
+readily palpable, sometimes even revealing irregularities along the
+course of a vessel. Such cases are not subjects for insurance. The
+recognition of such a condition is of great importance to the one who
+has it and he should be urged to go to his regular physician for
+thorough examination. Should the physician ridicule the idea, as has
+happened to me more than once when I was actively engaged in insurance
+work, the examiner has done his full duty to the company, the applicant,
+and himself.
+
+A life insurance examiner has a difficult position to fill. He has four
+people to satisfy; the applicant, the agent, the medical director and
+himself. The straight and narrow path of strict honesty is his only
+salvation. By being honest with himself he necessarily gives a square
+deal to the other three parties.
+
+No applicant who has palpable arteries or hypertension can be considered
+a first class risk. It can not be denied that men with arteriosclerosis
+live to an advanced age and may even outlive those who have apparently
+normal arteries, but the average life expectancy at any age for an
+arteriosclerotic is less than that for a normal person. The apparently
+healthy applicant who learns for the first time when examined for life
+insurance that he has the early or moderately advanced signs of arterial
+disease, should thank the agent and examiner for showing him the danger
+signals ahead. The sensible man then orders his life so that he puts as
+little strain on his heart, arteries, and kidneys as possible and may
+add many years to his life.
+
+It is on account of this very insidiousness of onset that I have
+elsewhere urged as a prophylactic measure the examination every six
+months of all persons over forty years of age. I am more and more
+convinced that it is of vital importance to the health of the public.
+
+As I have remarked, the average man consults his dentist at least once a
+year so that no tooth may be so far diseased that it can not be saved.
+It is purely a means of preserving the teeth. Why not do the same with
+the whole body? Of what use is it to save the teeth and lose the body?
+It seems to me that the great army of life insurance examiners are in an
+enviable position in their ability to add years of life to many men and
+women. I doubt whether they realize their importance in the campaign for
+health. I should urge life insurance companies not to employ recent
+graduates unless they have had at least a year's hospital experience.
+For the company as well as for the individuals I believe that there is a
+prognostic sense which the examiner should have and this can only be
+acquired by experience.
+
+I believe that arteriosclerosis and hypertension are increasing for the
+reasons which have been given in another chapter. There can be no doubt
+that when these conditions are recognized long before symptoms would
+naturally supervene, men and women would not only live longer but also
+die more comfortably and many very likely would be carried off by some
+disease having no relationship whatever to arteriosclerosis. Slight
+enlargement of the heart downward and to the left, accentuation of the
+second aortic sound at the base, a full pulse, arteries which are
+palpably thickened, increased blood pressure are signs to which
+attention must be paid.
+
+When the peripheral arteries are palpable they are not always sclerosed.
+The radial artery, the one usually palpated, may lie very close to the
+bone in a thin person. Under these conditions the artery can be easily
+felt. It is better then to palpate for the brachial as it lies beneath
+the inner edge of the biceps muscle. Should this artery be felt then
+very probably sclerosis is present. Opinion as to whether or not
+sclerosis is present, when it is slight, may differ. It is difficult at
+times to say definitely. Should such be the case the applicant should be
+most carefully questioned as to his family and past history, the heart
+should be carefully outlined by percussion and the blood pressure should
+be taken, both the systolic and diastolic pressures. The urine should be
+examined with particular care. I am aware that the average examination
+for life insurance is not made with the care which is bestowed upon a
+patient. Yet I see no reason why the same attention to detail should
+not be given in one as in the other. The examination of the great
+majority of applicants can he made in a short time, as there is no
+question of latent chronic disease. When the exception turns up he
+should be given a searching examination and a full report should be sent
+to the Medical Director. Only in this way will it be possible to weed
+out the undesirable risks.
+
+On the surface it does not seem to require any great diagnostic acumen
+to be a life insurance examiner. In the old days of many of the
+companies there were no examiners. The applicant was brought before the
+president or other appointed official and he was passed or rejected on
+his general appearance. This has changed, and now the medical department
+with its scores of examiners in the field is a well organized
+department.
+
+It seems to me that the examiner should be an exceedingly able
+diagnostician and prognosticator. There is no telling when he may be
+called upon to pass judgment on a borderline case. From personal
+experience I know how difficult it is to make a decision in some cases.
+These suspicious cases after a careful examination had better be passed
+by the examiner and a supplementary report sent to the medical director
+containing unbiased details. But no applicant with readily palpable
+arteries, even though the blood pressure be normal, should be considered
+a first class insurance risk.
+
+The question of the value of the diastolic pressure reading in
+examinations for life insurance is not yet settled to the satisfaction
+of all medical directors. Certain medical directors with clinical
+experience behind them, lay great stress on the increased diastolic
+pressure and consider a persistent diastolic of 100 mm. really more
+significant as an indication of hypertension than a systolic pressure of
+160 mm. Other directors pay little or no attention to the diastolic
+reading. Should an applicant show a systolic above the average normal on
+several successive readings, he is declined. When one takes into
+consideration the psychic effect of knowing that he is being examined
+for high blood pressure, it seems unfair to refuse insurance on such
+grounds as is constantly done.
+
+Up to the present there are no extensive series of life-expectancy
+tables in which hundreds of thousands of cases are analyzed from the
+diastolic pressure values. There are many such tables for the systolic
+pressures alone. In the tabulation of such statistics one must not lose
+sight of the important fact that the figures are taken by thousands of
+men of varying capacity and different degrees of intelligence. Such
+studies to be of any real value must be taken from records made at the
+home offices by capable men. We shall await these tables with interest.
+In the meantime we must be permitted to have the impression that the
+diastolic pressure has been much neglected. This has no doubt been due
+to the difficulty of measuring it with any degree of accuracy. Now with
+the auscultatory method and the correct place to read the diastolic
+pressure the results of blood pressure estimations should begin to have
+some value for statistical data.
+
+Clinically the diastolic is probably more important than the systolic.
+Until proof is brought to the contrary we shall believe that in life
+insurance examinations it has the same importance.
+
+
+
+
+CHAPTER XV
+
+PRACTICAL SUGGESTIONS
+
+
+The time spent in obtaining a careful history of a case is time well
+spent. Often the diagnosis can be made from the history alone, the
+physical examination merely adding confirmation to the data already
+obtained.
+
+The younger the patient who has arteriosclerosis, the more probable is
+it that syphilis is the etiologic factor. A denial of infection should
+have little weight if the history of possible exposure is present.
+Miscarriages in a woman should arouse the suspicion of lues in her
+husband. The complement-fixation reaction will often clear up an
+apparently obscure diagnosis.
+
+There are various ways of examining a patient but there is only one
+right way; the examination should be made on the bare skin. However
+skillful one may be in the art of physical diagnosis, he can gather few
+accurate data by examining over the clothes even if he use a
+phonendoscope.
+
+The immoderate eater is laying up for himself a wealth of trouble at the
+time when he can least afford to bear it. The ounce of advice in time is
+worth more to him than the pounds of medicine later.
+
+It is a wise maxim never to drive a horse too far. Apply that to the
+human being and the rule holds equally well.
+
+There may be no symptoms in a case of advanced arteriosclerosis. Do not
+on that account neglect to advise a patient in whom the disease is
+accidentally discovered.
+
+Many a man owes a debt of gratitude to the life insurance examiner. He
+rarely feels grateful.
+
+When a competent ophthalmologist refers a case to a general practitioner
+with the statement that he believes from the appearance of the fundus of
+the eye that arteriosclerotic changes are present over the body, the
+case should be most carefully examined. The earliest diagnoses are not
+infrequently made by the ophthalmologist.
+
+It is the part of wisdom never to have such a firmly preconceived idea
+of the diagnosis that facts observed are perverted in order to fit into
+the diagnosis. Let the facts speak for themselves.
+
+Beware of the snap diagnosis. Even in a case of well-marked
+arteriosclerosis when the diagnosis seems to be written in large letters
+all over the patient, go through the routine. Nine times out of ten this
+may seem needless. The tenth time it saves your conscience and
+reputation. Always consider that you are examining a tenth case.
+
+Gradual loss of weight in a person over fifty years old should arouse
+the suspicion of arteriosclerosis.
+
+Do not call the nervous symptoms displayed by a middle-aged man or woman
+neurasthenia until you have ruled out all organic causes, particularly
+arteriosclerosis.
+
+When palpating the radial artery, always use both hands according to the
+method already described. Pay attention to the superficial or deep
+situation of the artery.
+
+The examination of one specimen of urine does not give much information,
+especially if it should be found to contain no abnormal elements. Fairly
+accurate data may be gathered from the mixed night and morning urine;
+most accurate data from the twenty-four hour specimen. To be of any real
+value there should be frequent examinations of the day's excretion.
+
+In measuring the day's output a good rule is as follows: begin to
+collect urine after the first morning's micturition and collect all
+including the first quantity passed the next morning. It is best to
+examine the centrifugated urine for casts even though no albumin be
+present. It is useless to look for casts in an alkaline urine.
+
+Casts are not infrequently found in chemically normal urine from a
+middle-aged patient. Other things being normal, the finding has no
+significance. The kidneys must be carefully tested functionally.
+
+Blood pressure readings should always be taken with the patient in the
+same posture at every estimation. At the first examination it is
+advisable to take readings from both brachial arteries. Let the patient
+sit comfortably and relax all muscles.
+
+Differentiate as soon as possible between the uncompensated heart caused
+by valvular disease and that caused by arteriosclerosis. There is a
+difference in prognosis. Both give the same symptoms, and are treated
+similarly until compensation returns; thereafter the management of the
+two forms is different.
+
+Aortic incompetence that comes on late in life is generally the result
+of curling of the free margins of the valves caused by syphilitic
+arteriosclerosis. Prognosis is grave because of the fact that the heart
+muscle also is the seat of degenerative changes and compensatory
+hypertrophy is established with difficulty.
+
+When laying down a regime for a patient, consider his disposition, and
+individualize the treatment. Remember that exercise is an essential
+feature of the hygiene of the patient's life but do not forget to be
+explicit about the amount and character of the permissible exercise.
+
+In the prophylaxis of arteriosclerosis, a rational mode of living is the
+all-important factor. As a rule, the less meat one eats, the less is the
+liability of arterial degeneration as age advances. The exceptions to
+this rule are many, and probably depend upon the character of the "vital
+rubber" with which the individual begins life.
+
+The diet in well-marked cases of arteriosclerosis should be carefully
+selected with regard to its nutritive and non-irritating character.
+Animal proteins should be sparingly used. Milk should have an important
+place in the dietary.
+
+No drug relieves the pain of uncomplicated aneurysm as surely as iodide
+of potassium.
+
+Iodides frequently upset the stomach. Be cautious in the use of them.
+The irritable stomach may turn the scales against your patient.
+
+Use cardiac stimulants with care and judgment. If all the valuable
+ammunition is used up at first, the fight will be lost.
+
+Use digitalis with especial care. Its chief usefulness is in steadying
+the decompensated heart, improving the conduction of impulses, and
+increasing the tone of the cardiac muscle. _It should never be given to
+patients with very slow pulses, the subjects of Stokes-Adams syndrome._
+Digitalis has been found to produce partial to complete heart block when
+therapeutically administered.
+
+Remember that in the uncompensated heart morphine not only eases the
+oppressive dyspnea, but also steadies and stimulates the heart.
+
+See to it that the patient has a daily movement of the bowels. In the
+early stage try the effect of liquid paraffin or of the mineral waters
+such as Pluto, or Hunyadi Janos, or artificial Carlsbad salts (Sprudel
+salts). These last can be made as follows: Sodium chloride, ounce I;
+sodium bicarbonate, ounce II; sodium sulphate, ounce IV. Take two
+tablespoonsful of this in a glass of hot water before breakfast. Should
+these not succeed, assist the action of the drugs by the use of enemata.
+The pill of aloin, strychnine sulphate, and extract of cascara, with the
+addition of a small quantity of hyoscyamus, is a mild tonic purgative.
+In cases of constipation with high tension, there is no drug as valuable
+as calomel or one of the other mercurials given occasionally.
+
+Never give Epsom salts unless copious watery stools are desired to
+deplete effusion into the serous cavities or into the subcutaneous
+tissue.
+
+Chronic constipation increases the gravity of the prognosis.
+
+In case of suppression of urine and anasarca, hot air packs may be of
+value. The patient may be wrapped in a hot wet sheet and covered with
+blankets. I do not believe in administering pilocarpine to assist the
+sweating.
+
+Remember to treat the patient and not the disease. The careful hygienic
+and dietetic treatment, combined with the least amount of drugging, is
+the best and most rational method of treatment.
+
+
+
+
+INDEX
+
+
+ A
+
+ Abdominal symptoms, 201
+
+ Aconite in treatment, 242
+
+ Acquired arteriosclerosis, 159
+
+ Adami, effect of syphilis in aorta, 45
+
+ Adventitia, 28
+
+ Age in arteriosclerosis, 161
+
+ Albuminuria, 221
+
+ Albutt's classification of arteriosclerosis, 186
+
+ Alcohol, 166, 228, 235
+
+ Anatomy, 25
+
+ Angina abdominalis, 201, 216
+ pectoris, 197, 216
+ pseudo, 216
+
+ Angiosclerosis, 26, 64
+
+ Aorta, 27
+ anatomical lesions in, 33
+ Aschoff on, 35
+ normal, 41
+ syphilis in, 44
+ thoracic, 29
+ thoracic and abdominal, arteriosclerosis of, 39
+ velocity of blood in, 66
+
+ Aortic incompetence, 61, 258
+ stenosis, 60
+
+ Aortitis, acute, 165
+
+ Arcus senilis, 191
+
+ Arrhythmia, tonal, 92, 102
+
+ Arterial pressure, 85
+ symptoms, 189
+
+ Arteries, 29
+ examination of, 172, 177
+ general structure of, 27
+ large, 30
+ adventitia of, 30
+ palpable, 189
+ pulmonary, arteriosclerosis of, 63
+
+ Arteriocapillary fibrosis, 26
+
+ Arteriosclerotic endocarditis, 60, 219
+
+ Artery, coronary, cross-section of, 36
+ pulmonary, 209
+ radial, 29
+
+ Aschoff on aorta, 35
+
+ Atheroma, simple, 32
+
+ Atheromatous abscess, 38
+
+ Auricular fibrillation, 133
+ flutter, 131
+
+ Auscultation, 176
+
+ Auscultatory blood pressure phenomenon, 90
+ method of taking blood pressure, 83
+ percussion, 175
+
+
+ B
+
+ Balneotherapy, 233
+
+ Basch's blood pressure instrument, 70
+
+ Blood, circulation of, 65
+ velocity of, 65
+ in animals, 66
+ in aorta, 66
+ in capillaries, 66
+ viscosity of, 68
+
+ Blood pressure, 68
+ auscultatory method of taking, 83
+ clinical applications of, 147
+ diurnal variations of, 102
+ drugs influencing, 120
+ estimation of, 179
+ in cancer, 118
+ in collapse, 118
+ in exercise, 105
+ in head injuries, 148
+ in hemorrhages, 105, 118, 148
+ in infectious diseases, 153
+ in kidney diseases, 155
+ in meningitis, 118
+ in obstetrics, 152
+ in pulmonary tuberculosis, 119
+ in shock, 105, 148
+ in surgery, 147
+ in typhoid fever, 118, 154
+ in valvular heart disease, 155
+ increase of, 55
+ instruments, 70
+ Brown's, 74
+ Cook's, 71
+ Erlanger's, 72
+ Faught's, 75, 80
+ Hill and Barnard's, 70
+ Hirschfelder's, 73
+ K. Vierordt's, 70
+ Marcy's, 70
+ Potain's, 70
+ Riva Rocci's, 70
+ Roger's, 77
+ Sanborn's, 80
+ Stanton's, 72
+ technique of, 80
+ "Tycos," 77
+ v. Basch's, 70
+ v. Recklinghausen's, 76
+ mechanism of, 55
+ normal variations of, 88
+ phenomenon, auscultatory, 90
+ precautions when estimating, 181
+ value of, 181
+
+ Bowman's capsules, sclerosis of, 62
+
+ Brain, changes in, 62
+
+ Brown atrophy, 60, 118, 201
+
+
+ C
+
+ Calcification of media, 43, 59
+
+ Cancer, blood pressure in, 118
+
+ Capillaries, anatomy of, 27, 31
+
+ Capillary pulse, 67
+
+ Cardiac dullness, 172
+ irregularities in arteriosclerosis, 131
+ symptoms, 195
+
+ Cerebral symptoms, 203
+
+ Circulation of blood, 65
+ physiology of, 65
+
+ Cirrhosis of liver, 64, 216
+
+ Classification of arteriosclerosis, 32, 37
+ Allbutt's, 186
+
+ Collapse, blood pressure in, 118
+
+ Congenital arteriosclerosis, 157
+
+ Cook's blood pressure instrument, 71
+
+ Cor bovinum, 116
+
+ Coronary artery, cross section of, 36
+
+ Corpus luteum, 241
+
+
+ D
+
+ Definition of arteriosclerosis, 26
+
+ Diabetes mellitus, 216
+
+ Diagnosis, 210
+ differential, 215
+ early, 210
+ ophthalmic examination in, 214
+
+ Diastolic pressure, 69, 83, 85, 94
+ importance of, 97
+
+ Dicrotic pulse, 123
+
+ Dietetic treatment, 235
+
+ Differential diagnosis, 166, 215
+
+ Diffuse arteriosclerosis, 32, 37, 38, 57
+
+ Digitalis in treatment, 246, 259
+
+ Diuretin in treatment, 246
+
+ Drug intoxications, 166
+
+ Drugs influencing blood pressure, 105, 120
+
+ Ductless glands, 171
+
+ Dullness, cardiac, 172
+
+ Dyspeptic symptoms, 184
+
+ Dyspnea, 184
+ treatment of, 248
+
+
+ E
+
+ Electrocardiogram, 126
+
+ Embolism, 59
+
+ Endarteritis deformans, 47
+ obliterans, 46
+
+ Endocarditis, arteriosclerotic, 60, 219
+
+ Endothelial lining, 27
+ tubes, 31
+
+ Epistaxis, 184, 221
+
+ Erlanger's blood pressure instrument, 72
+
+ Erythromelalgia, 192, 208
+
+ Estimation of blood pressure, 179
+
+ Etiology, 157
+
+ Examination of arteries, 172, 177
+ of heart, 172
+ of urine, 257
+
+ Exercise, blood pressure in, 105
+ in prophylaxis, 225
+ in treatment, 230
+
+ Experimental arteriosclerosis, 50
+
+ Extrasystole, 138
+
+
+ F
+
+ Faught's blood pressure instrument, 75, 80
+
+ Fibrillation, auricular, 133
+ ventricular, 138
+
+ Fibrolysin in treatment, 243
+
+ Fingernail palpation, 178
+
+ Finger tip palpation, 179
+
+ Flutter, auricular, 131
+
+ Food poisons in arteriosclerosis, 163
+
+
+ G
+
+ Gibson's law, 154
+
+
+ H
+
+ "H" wave, 126
+
+ Habits, personal, 234
+
+ Head injuries, blood pressure in, 148
+
+ Headache, 184
+ treatment of, 248
+
+ Heart block, 140
+ boundaries, 172
+ examination of, 172
+ hypertrophy of, 60
+ physical examination of, 172
+ stimulants, 243, 246, 259
+ symptoms, 188
+
+ Hemorrhages, blood pressure in, 118
+
+ Henle, membrane of, 29
+
+ Hill and Barnard's blood pressure instrument, 70
+
+ Hirschfelder's blood pressure instrument, 73
+
+ His, bundle of, 141, 197
+
+ Hygienic treatment, 230
+
+ Hyperpietic arteriosclerosis, 186
+
+ Hypertension, 60, 106, 169, 185, 249
+ cause of arteriosclerosis, 159
+ classification of cases, 112
+
+ Hypertrophy of left ventricle, 58
+
+ Hypotension, 117
+
+
+ I
+
+ Incompetence, aortic, 61, 258
+
+ Indicanuria, 167
+
+ Infants, arteriosclerosis in, 158
+
+ Infectious diseases in arteriosclerosis, 163
+ blood pressure in, 153
+
+ Insomnia, treatment of, 248
+
+ Intermittent claudication, 192, 208
+ treatment of, 247
+
+ Intoxications, chronic drug, 166
+
+ Intracranial tension, 105
+
+ Involutionary arteriosclerosis, 187
+
+ Iodides in treatment, 238, 247, 259
+
+
+ K
+
+ Kidney diseases, blood pressure in, 155
+
+ Kidneys, sclerosis of, 61, 170
+
+
+ L
+
+ Life insurance, relation to, 249
+
+ Light percussion, 174
+ touch palpation, 175
+
+ Liver, cirrhosis, 64, 216
+
+ Local symptoms, 207
+
+
+ M
+
+ Marey's blood pressure instrument, 70
+
+ Maximum pressure, 85, 94
+
+ Mean pressure, 85
+
+ Media, calcification of, 43, 59
+
+ Medicinal treatment, 238
+
+ Meningitis, blood pressure in, 118
+
+ Mental strain, 168
+
+ Mesaortitis, 45, 47, 49, 165
+
+ Mesentery, cross-section of small artery in, 56
+
+ Milk diet, 237
+
+ Minimum pressure, 86, 94
+
+ Moenckeberg type of arteriosclerosis, 43
+
+ Morphine in treatment, 243
+
+ Mosenthal test meal, 221
+
+ Muscular overwork, 169
+
+
+ N
+
+ Nervous symptoms, 191
+
+ Nitrites in treatment, 240
+
+ Nitroglycerin in treatment, 241
+
+ Nodular arteriosclerosis, 32, 37
+
+ Normal blood pressure variation, 88
+
+
+ O
+
+ Obstetrics, blood pressure in, 152
+
+ Occupation in arteriosclerosis, 162
+
+ Ocular symptoms, 190
+
+ Ophthalmic examination, importance in early diagnosis, 214, 256
+
+ Orthodiagraph, 173
+
+ Overeating, 167, 212, 225, 235
+
+ Overwork, muscular, 169
+
+
+ P
+
+ "P" wave, 129
+
+ "P-R" interval, 130
+
+ Palpable arteries, 189
+
+ Palpation, 174, 180
+ fingernail, 178
+ finger tip, 179
+ light touch, 175
+
+ Pathology, 32
+
+ Percussion, 174
+ auscultatory, 175
+ light, 174
+
+ Peripheral symptoms, 207
+
+ Personal habits, 234
+
+ Phlebosclerosis, 64
+
+ Phthalein test, 221
+
+ Physical signs, 183
+
+ Physiology of the circulation, 65
+
+ Potain's blood pressure instrument, 70
+
+ Practical suggestions, 256
+
+ Pressure, arterial, 85
+ ausculatory method of determining, 83
+ diastolic, 83, 94
+ estimation of, 179
+ in surgery, 147
+ maximum, 85, 94
+ normal variations, 88
+ pulse, 83, 85, 87, 100
+ systolic, 82, 85
+ technique, 80
+ venous, 120
+
+ Prognosis, 218
+
+ Prophylaxis, 224
+ exercise in, 225
+
+ Pseudo angina pectoris, 216
+
+ Pulmonary artery, 209
+ arteriosclerosis of, 63
+ tuberculosis, blood pressure in, 119
+
+ Pulse, 123
+ capillary, 67
+ deficit, 135
+ dicrotic, 123
+ in arteriosclerosis, 123
+ pressure, 69, 83, 85, 87, 100
+ rate, 69
+ venous, 123
+
+ Purgatives in treatment, 244, 259
+
+ Pyrosis, 184
+
+
+ Q
+
+ "Q R S" complex, 129
+
+
+ R
+
+ Rabbits, lesions produced experimentally in, 50
+
+ Race in arteriosclerosis, 161
+
+ Radial artery, 29
+
+ Radials, sclerosis of, 43
+
+ Raynaud's disease, 192, 207
+
+ Recklinghausen's blood pressure instrument, 76
+
+ Renal disease, 169
+ symptoms, 199
+
+ Rest in treatment, 242
+
+ Riva-Rocci's blood pressure instrument, 70
+
+ Rogers' blood pressure instrument, 77
+
+
+ S
+
+ Sanborn's blood pressure instrument, 80
+
+ Scaphoid scapula, 158
+
+ Schwellungsperkussion, 174
+
+ Sclerosis of veins, 64
+
+ Senile arteriosclerosis, 32, 37, 43, 59
+
+ Sex in arteriosclerosis, 161
+
+ Shock, blood pressure in, 105, 148
+
+ Spinal symptoms, 205
+
+ Spirochaeta pallida, 45
+
+ Stanton's blood pressure instrument, 72
+
+ Stenosis, aortic, 60
+
+ Stokes-Adams syndrome, 197
+
+ Stomach, ulcer of, 216
+
+ Strain hypertrophy, 47, 54, 55
+
+ Surgery, blood pressure in, 147
+
+ Symptomatic treatment, 245
+
+ Symptoms, 183
+ abdominal, 201
+ arterial, 189
+ cardiac, 195
+ cerebral, 203
+ dyspeptic, 184
+ dyspnea, 184
+ general, 183
+ headache, 184
+ heart, 188
+ local, 207
+ nervous, 191
+ ocular, 190
+ peripheral, 207
+ pyrosis, 184
+ renal, 199
+ special, 194
+ spinal, 205
+ vertigo, 184
+ visceral, 201
+
+ Syphilis, 165
+ in aorta, 44
+
+ Syphilitic arteriosclerosis, 37
+
+ Systolic pressure, 69, 82, 85, 94
+ importance of, 97
+
+
+ T
+
+ "T" wave, 130
+
+ Technique of blood pressure instruments, 80
+
+ Thayer and Fabyan, 34
+
+ Theocin, 247
+
+ Thoma on arteriosclerosis, 33
+
+ Thoracic aorta, 29
+
+ Thyroid extract in treatment, 239
+
+ Tobacco, 167, 212, 234
+
+ Tonal arrhythmia, 92, 102
+
+ Toxic arteriosclerosis, 186
+
+ Treatment, 229
+ aconite in, 242
+ balneotherapy in, 233
+ corpus luteum, 241
+ dietetic, 235
+ digitalis in, 246, 259
+ diuretin in, 246
+ exercise in, 230
+ fibrolysin in, 243
+ heart stimulants in, 243
+ hygienic, 230
+ iodides in, 238, 247, 259
+ medicinal, 238
+ morphine in, 243
+ nitrites in, 240
+ nitroglycerin in, 241
+ of dyspnea, 248
+ of headache, 248
+ of insomnia, 248
+ of intermittent claudication, 247
+ personal habits in, 234
+ purgatives in, 244, 259
+ rest in, 242
+ symptomatic, 245
+ theocin in, 247
+ thyroid extract in, 239
+ Trunecek's serum in, 243
+ venesection in, 242
+ veratrum viride in, 242
+
+ Trunecek's serum in treatment, 243
+
+ Tuberculosis, blood pressure in, 119
+
+ Tunica intima, 28
+ media, 28
+
+ "Tycos" blood pressure instrument, 77
+
+ Typhoid fever as cause of arteriosclerosis, 164
+ blood pressure in, 118
+
+
+ U
+
+ Ulcer of stomach, 216
+
+ Urine, examination of, 257
+ suppression of, 259
+
+
+ V
+
+ Valvular heart disease, blood pressure in, 155
+
+ Vasa vasorum, 29
+
+ Veins, anatomy of, 30
+ sclerosis of, 64
+
+ Velocity of blood in animals, 66
+ of blood in aorta, 66
+
+ Venesection in treatment, 242
+
+ Venous pressure, 120
+ pulse, 123
+
+ Ventricle, left, hypertrophy of, 58
+
+ Ventricular fibrillation, 138
+
+ Veratrum viride in treatment, 242
+
+ Vertigo, 184
+
+
+ * * * * *
+
+
+Transcriber's Notes: Irregular hyphenation has been preserved, as in
+blood pressure and blood-pressure. Both "Hg" and "Hg." appear.
+
+Minor typographical errors and inconsistencies have been silently
+normalized.
+
+The original printed list of illustrations shows the original
+locations; they have been moved closer to their discussion area
+in the text to not interrupt the flow of reading.
+
+Page 244 Prescription symbol is replaced with R_{x}
+
+Page 259 Apothecaries ounce symbol replaced with "ounce"
+
+
+
+
+
+End of the Project Gutenberg EBook of Arteriosclerosis and Hypertension:, by
+Louis Marshall Warfield
+
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