response to physiologic stimuli, and that such a reaction may be entirely natural, if not essential. Here it becomes physiologic. It may be said, I think without question, that the most important item in the treatment of chronic nephritis is the preservation of cardiac compensation. Neither is there any question but that the elevation in systolic pressure while bearing a direct casual relation to the cardiac hypertrophy, also operates in conjunction with it in forming a compensatory mechanism which alone is able to maintain an adequate kidney function. They are, consequently, essential to the preservation of life, and should be protected by every hygienic and dietetic safeguard. In connection with treatment by hygienic and dietetic measures, it is often most strikingly demonstrated that such measures, if they result in relief of distressing symptoms, cause a reduction in pulse pressure and that this occurs even when the systolic level is not materially affected. In my own work I have come to look upon this alteration as auguring good, even when, as already mentioned, the systolic level remains the same (see Fig. 62). I cannot agree with those authorities who divide the treatment of this condition into (a) correction of the tension and (b) the administration of specific drugs. It is rare except in emergency that such drugs are required (as to relieve threatened death from pulmonary edema, acute dilatation of the heart or apoplexy) and they may and frequently do cause harm. Therefore, nitrites should be reserved for emergency and then given only when carefully checked by the clinician. Even then they are often of little value because of the uncertainty of their action. The appearance of dropsy in chronic nephritis with high pressure almost invariably presages cardiac failure. At this stage the digitalis bodies become our sheet anchor of treatment. They should not be withheld because the bloodpressure is high, as they have been found to act just as well, or even better, in the presence of high pressure than with a decreased pressure.1 That the ingestion of sodium chloride favors fluid retention is well known, so that its reduction should be encouraged, in any case where the presence of edema fails to respond to other methods, although I am not yet willing to state that salt restriction should be included among the dietetic measures in every case. Space will not permit of an extended discussion of the many dietetic, hygienic and therapeutic measures which may be employed in the management of the disease. Those desiring specific information relative to the variety and to the effect of such measures will find them briefly discussed in Chapters XXIII and XXIV. 1 A. R. Elliott, Jour. A. M. A., Nov. 21, 1914, lxiii, 21, 1878. CHAPTER XIX CARDIAC DISEASE: MYOCARDIAL, VALVULAR, AND FUNCTIONAL. MYOCARDIAL INSUFFICIENCY Significance of Term.-From a practical standpoint it would seem advisable to employ the general term myocardial insufficiency, to the exclusion of all others, when discussing from a clinical standpoint the pathologic changes which may occur in the heart muscle; for, while we recognize pathologically a sharp line of demarcation between acute and chronic inflammation, and between fatty degeneration, fibroid degeneration or fibrosis, senile heart and chronic cardiac insufficiency, in the majority of cases there is no way by which these various conditions can be distinguished from each other clinically. Any attempt to separate the various forms of myocardial change, by a clinical study of the case, is merely an exhibition of ignorance, for the symptoms supposed to indicate different forms of myocardial disease may be caused by the same pathologic conditions. Also various pathologic changes may give rise to identical trains of symptoms, so that all efforts to clinically classify them must necessarily fail. Chronic myocarditis causes weakness in the cardiac power, irrespective of the cause of the pathologic change in the heart muscle. This is evidenced clinically by an inadequacy of the circulation either during rest or following a demand for increased power. FIG. 62.-Male. Aged sixty. Retired stock broker. Cardiovascularrenal disease. Myocardium in fair condition, arteries moderately rigid. The height of systolic pressure and large pulse pressure are characteristic of arterial rigidity and cardiac overaction. The remissions are unexplained except on the grounds of varying excitement and activity. Measures directed toward relief of high pressure very unsuccessful, although relief from dyspnea, insomnia and early morning headache was quite marked, and has continued in spite of the gradual average rise in systolic and pulse pressures. (A) Large doses of tincture of aconite failed to reduce pressure. (B) An attack of acute rhinitis occurred. (C) General condition good. Has spent summer at seashore resort. (D to E) Not under any treatment. Absence of all unpleasant symptoms and general condition excellent. Note the stationary pulse pressure in spite of moderate variations in both systolic and diastolic. (F) Attack of grippe. Confined to bed until 1-16-'16. Attack rather severe with marked toxemia and prostration. Note effect of treatment and rest upon systolic, diastolic and pulse pressures. (G) Note sharp rise in systolic as result of extraordinary exertion following severe infection, accompanied by dizziness, insomnia and cough. Subsequent treatment directed toward circulation including the use of strychnin and caffein by mouth. Etiology.-Chronic myocardial insufficiency is a condition of the heart muscle resulting usually from some disturbance in nutrition of the heart muscle. Leslie Thorne1 says that two of the most common forms of muscle degeneration resulting from hypertension are atheroma and fatty degeneration. The modus operandi of degeneration is probably that of a disturbed blood-supply to the heart itself, due to a narrowing of the coronary arteries. It is therefore essentially a chronic progressive process and, from the intrinsic nature of the change, when once the process has become fairly well started it is but slightly amenable to treatment. Bruce2 dwells upon the frequency of cardiac degeneration, associated with glycosuria, and also the frequent relation of gout to chronic myocarditis. A most important factor, never to be forgotten in this strenous age, is the effect of the constant strain of responsibility upon business men, legislators, professional men, etc., where we find the development of high pressure particularly common, resulting in cardiac enlargement, with more or less insufficiency, all of which denote the beginning of the end, unless the overstress be reduced. Belonging to the same class of cases are those due to indiscretions in diet and sedentary habits with insufficient exercise. Here the intra-abdominal vessels are subjected to abnormal and prolonged strain, which leads in time to sclerosis of their coats, to increased blood-pressure, cardiac overwork and eventually to degeneration of the myocardium (see Fig. 62). 1 Lancet, June 4, 1910. |