Cardiac Strain.
I will now proceed to consider the clinical characters of a class of cases in which you, Sir, are particularly interested—strain of the heart in middle and advanced life. To make this part of my subject more plain, I will discuss in the first place acute strain of the heart as it occurs after the fortieth year; afterwards I will consider the condition of the heart and arteries at this age in persons who have strained them in youth or early manhood.
A man of 65, who came to me complaining of his heart, gave the following account of the commencement of his trouble:—Four years previously, on making a very hard stroke at golf (the ball was bunkered), he was suddenly seized with a sensation of something having happened in his heart. He played up to the next hole, but now felt the chest oppressed; he sat down and got relief. This experience was repeated, and he gave up the round. Walking home two miles, he had to sit down occasionally with the same feeling. Ever since that occurrence exertion had produced the same effect. I found the ordinary physical signs of enlargement of both sides of the heart; a scarcely perceptible impulse; the cardiac sounds extremely feeble, the second being of a finely ringing quality; the pulse tense, quiet and regular, but the radial artery by no means sclerosed. The patient's principal complaints were of irregular action of the heart, which troubled him on lying down or when he was dyspeptic; and, as I have said, of post-sternal oppression on exertion. This man had neither albuminuria nor emphysema, but he had frequently suffered from ordinary articular gout. Belonging to this type of cardiac strain I have notes in all of 11 cases, which I will briefly summarise. Eight were men, three women; and their average age was 56. In all but one of them the heart was large, with feeble præcordial impulse; the sounds were small and feeble; the aortic diastolic sound was often ringing; in but one case was there a murmur—aortic systolic; with few exceptions the rhythm and the rate of the heart were ordinary. In half the cases the radial artery was sclerosed; in the majority the tension was not increased. Persons who strain their heart after middle life chiefly complain of præcordial oppression, dyspnœa on exertion, a sense of palpitation and irregular action of the heart, and pain, which may amount to angina; and they may tell us that distress and disability in these different forms have troubled them for years. You will have observed that the man whose case I have read in particular was the subject of gout; and this brings me to the interesting fact that of these 11 individuals seven were gouty. We have already seen how greatly reduced is the resistance of the cardio-vascular system in gouty subjects; and we are prepared for the readiness with which their heart may be strained by exertion—a matter of obvious importance prophylactically. In other cases not included in this group the strain took the form of valvular injury, or it affected hearts already the seats of old-standing valvular lesions of rheumatic origin; but the present is not the occasion to discuss these. Nor need I add that a not infrequent result of acute strain of the aged heart, whether its valves have been already damaged or its myocardium badly nourished, is sudden death. Now, I can understand that some of my audience might object to the application of the term "strain" to the effect of exertion in gouty and senile hearts, just as Professor Clifford Allbutt, who is universally recognised as the earliest and highest authority on this subject, suggests that the clinical expression "strain of the heart" relates only to comparatively young subjects free or nearly free from degeneration.[14] It might be contended with great reason that exertion in these subjects is not a cause of strain or dilatation of the heart, but simply a test, as it were, or the proof, of cardiac debility and disability. But when we come to consider cardiac strain a little more closely, it may be just as easily maintained that every dilated heart, every dilated cardiac chamber, every dilated blood-vessel has been strained. Whether, on the one hand, valvular disease, Bright's disease or emphysema, or, on the other hand, myocardial degeneration, has disturbed that cardinal condition of a normal circulation that the driving power must always exceed the resistance ahead, over-distension and dilatation of the cavities, with excessive stretching of their walls, constitute or consist in mechanical strain. However, laying aside theoretical discussions of this character, the great practical fact remains, that when the aged and ill-nourished heart is over-distended from sudden and severe exertion, neither the elastic nor the muscular tissues of its walls can bear the strain; it becomes dilated; for the future it acts at a mechanical disadvantage; and as often as this may occur it suffers still more in its efficiency. On the other hand, it is really in confirmation of this consideration, though apparently in opposition to it, that the heart may diminish somewhat in size, and præcordial distress disappear, under strict treatment continued for a sufficient length of time.