6. For the man and woman of forty years of age and upwards, most of the acute specific fevers are affairs of the past. But the liability to several of them remains, and, very unfortunately, the liability to those acute specific processes which may attack the cardio-vascular system—influenza in particular, and less often typhoid fever, rheumatism, diphtheria and pneumonia, as well as septicæmia of different forms or kinds, which works havoc throughout the entire circulation. I should have had more to say under this head but for the fact that our distinguished Fellow and former President, Dr. Sansom, has thoroughly investigated it, and on more than one occasion laid the results before you.
7. I will not occupy your time this evening in tracing the origin of certain cases of cardio-vascular disease in middle and advanced life to chronic affections of different kinds. Besides the obvious effects upon the heart, blood and blood-vessels, of anæmia, exhaustion, &c., we meet with such grave lesions as fatty degeneration from pernicious anæmia and other blood disorders; profound circulatory derangements and occasionally valvular lesions in Graves's disease, and others.
8. I now pass on to complex causes. In addition to the definite and distinct influences which I have mentioned as threatening the heart in this stage of life, there are two which are intimately associated with other causes of cardio-vascular disease, but still deserve to stand out independently. The first of these is emphysema, and along with it other chronic affections of the lungs and pleura, which strain the right ventricle; the second is chronic Bright's disease, which similarly strains the left ventricle. I shall have frequent occasion to return to these two morbid states in different parts of my subject. I mention them here to give them the position which they deserve as influences that threaten the function and still more the structure of the heart and arteries. They are often associated with each other, and each or both of them with one or more of the unfavourable influences I have just enumerated, particularly alcohol, disordered metabolism and gout. And this brings me to the many instances in which the different influences that threaten the circulatory organs in middle and advanced life act together in different combinations. Alcoholism is equally common amongst the poor, whose circulation is subjected to mechanical stress, whilst it is impoverished by want; the well-to-do, who lead luxurious, sedentary enervating lives; and, as I have already observed, the keen active business or professional man who overworks his brain on stimulants. In this country at least, gout appears to be all-pervading, and as an unfavourable influence on heart and vessels it often cannot be dissociated from alcohol, sedentary habits, worry, plumbism, Bright's disease and emphysema.
Thus, in our study of combinations of morbific influences we come to appreciate the evil effect of certain occupations upon the circulation in middle life. The business man is exposed to the unhealthy actions on his heart of confinement to a close office or shop, worry, irregular hasty feeding, alcoholic indulgence in connection with his trade or profession, and unwise attempts at violent muscular exercise at the week-end or in the holiday season; or he may be guilty of entire disregard of the rules of bodily and mental hygiene, and bring on in this way premature degeneration of his cardio-vascular system. Still more numerous are the causes at work in the production of "soldier's heart." We have but to picture to ourselves, if we can, the physical strain, the mental excitement, the bodily hardships—including exposure to both extremes of temperature—and the coarse fare which have been the lot of many thousands of our brave troops in the Boer war, to understand how the fighting soldier "ages" quickly, and, in particular, ages in his heart and arteries. Add to these unfavourable influences syphilis, alcohol and tobacco (which, unfortunately, must be added in many instances), and the chance of escape from disease of the circulation in the soldier is practically nil. But "soldier's heart" is also met with elsewhere than in the army. The clergyman from the slums of London or other great city, who has lived and toiled and—it may be said truly—has fought with various success through alternate periods of excitement and depression, and has thus suffered much both in mind and body, comes to us with high-tension pulse, a tortuous radial artery, a large heart and a systolic murmur over the aorta, and complains of an attack of angina. His wife, who has laboured in the parish for years (she is 76, and still active in her work of charity), has also a thickened radial artery, a large heart, and a systolic basic murmur, with no discoverable cause of these evidences of a diseased circulation but the life that she has led amongst the poor around her. Perhaps such cases of cardio-vascular disease might be most correctly said to be due to the wear and tear of life. They are met with also in the traveller or explorer, who has spent most of his life in search of adventure; and they are found in a man who has never left home, but whose years have been filled with the toil and anxiety of his position as an owner of land, or with prolonged litigation.
Such are the principal natural influences which individually or in different combinations threaten or assail the sound heart and blood vessels after the age of 40. I have given but a broad, hasty sketch of them entirely from my own recent observations, and I know that I have omitted some which in your opinion might deserve mention, but which possess no special interest in relation to this period of life—for example, the agents of acute infections of the endocardium, and also new growths, pregnancy and parturition. Let me now sum up the results, and say that whatever changes the cardio-vascular system may present in middle and advanced life, beyond those which we have found to be natural to it at those particular periods, are pathological—the result of physical stress, nervous influences, extrinsic poisons, disturbances of metabolism, syphilis, acute disease, or chronic disease; or are associated with chronic nephritis, emphysema or different combinations of the preceding causes, with various occupations or positions in life, or with other influences of less importance. It is necessary, however, to qualify this statement in two respects. In the first place, the heart and vessels may have been so damaged already, that is, in early life, that they fall victims to influences which, whether in kind or in degree, would have been insufficient to produce idiopathic disease of these organs. This brings me to the subject of old-standing valvular disease (mostly rheumatic in origin), chronic strain, and adherent pericardium in middle-aged and old subjects. A considerable proportion of our cases are of this type, and they have to be mentioned here for the sake of giving completeness to the plan of arrangement, but they are outside the range of our immediate subject. In the second place, hearts and arteries at 40 that appear to the naked eye free from damage may be molecularly weak, and unable to offer effective resistance even to influences of an every-day character. I have now arrived at the last, and certainly one of the most interesting, of the causes of disease of the heart and arteries in middle and advanced life. There are some persons whose hearts and arteries cannot carry them through the wear and tear of what may be called ordinary life for more than 40 or 50 years. The vital energy of the tissues of these organs is exhausted prematurely; they are already old at 45; degeneration of the muscle and other cells sets in early, reminding us of the essential myopathic paralysis of children. This type of case is described as "family heart," for it also runs in families—three, four, five, or more members of which, as in a number of instances that I have observed, may have all died suddenly of cardiac disease—some of them at an early age. Similarly, it is not by any means unusual to find quite young subjects, say of 30, with vessels already much enlarged; and I may add, equally young subjects with their lungs already emphysematous although there is no history of respiratory strain, reminding us of the very common association of emphysema with arterial sclerosis in old age. These cases of family heart and premature arterial sclerosis are the links that connect disease of the heart and arteries in middle and advanced life of definitely pathological origin with the genuinely senile changes in the tissue-elements which render existence untenable at last, and which may be said to be the result of the exhaustion of their nutritional activity by "the thousand natural shocks that flesh is heir to."
LECTURE II.
Mr. President and Gentlemen,—In my last lecture I presented to you a brief account of the condition of the organs of circulation between the ages of 40 and 75, and I then proceeded to direct your attention to the principal influences which may disorder and damage them during that period of life. I will now attempt to describe the clinical characters and course of the affections of the heart and arteries, as I have observed them, in connection with these different influences respectively—whether gout, mechanical stress, syphilis, or other. Thereafter, if time permits, I may be able to examine the different symptoms and signs individually in order to discover the value of each as a guide in diagnosis.