Hemodynamic effects of digoxin in latent cardiac failure.

TREATMENT of cardiac failure usually includes several therapeutic maneuvers that are used concurrently in order to restore the state of compensation: (1) elimination of the overload due to exercise or emotional stress, which can be accomplished by rest, (2) enhancemenat of performance of the heart by the administration of cardiotonic drugs, of which digitalis is the principal one, (3) decrease in blood volume and reduction of extracellular fluid by sodium restriction and administration of diuretics. Clinical observations leave no doubt that in milder cases one of the three methods may suffice in abolishing signs and symptoms of heart failure. In more advanced cases either two or all three methods have to be used to control failure. In an earlier communication' it was demonstrated that clinical restoration of the state of compensation occurs without circulatory dynamics having reverted to a normnal state; furthermore , in the majority of patients who recover clinically from cardiac failure, gross hemo-dynamic abnormalities are present at rest or during exercise or both. Such patients then appear to be in a state of latent cardiac failure , which is clinically controlled by reduction of activities, by dietary restriction, and by administration of drugs. Hemodynamic responses to digitalis have been studied in patients with overt heart failure,2-11 in patients with no evidence of cardiac disease,12-14 and in patients with cardiac disease but not in failure.10' 13, 15 However , no studies are available dealing with the effect of digitalis in the state of latent heart failure as defined above. The purpose of this paper is to evaluate the action of this drug under such circumstances and to compare cardiac performance in patients treated for cardiac failure by the two other methods with that after digitalis had been added to them. Material and Methods This report deals with a study of 15 carefully selected patients with heart failure and normal sinus rhythm. In order to deal with comparable cases in a homogeneous group, only patients with a primary left ventricular overload were included: hypertensive cardiovascular disease, isehemie cardiac disease, and aortic valvular heart disease. The patients showed, upon hospital entry, overt cardiac failure: some patients presented the picture of pure left ventricular failure, others combined right and left heart failure. In all patients fluid retention was present. Only such patients were included who had had no digitalis for at least a month prior to entry. The patients were placed …