Abstract
Recent medical literature is replete with articles i concerning the treatment of congestive heart failure, acute1-7 and chronic,9-16 with agents that increase venous capacitance and reduce preload, and with those that decrease systemic arteriolar resistance and reduce afterload. These concepts are not new17,18 and their recent widespread acceptance as therapeutic modalities in the treatment of congestive heart failure should not obscure the primary role of digitalis glycosides.19-22 This fact is best perceived after a review of basic concepts and a classification of the etiologies of congestive heart failure. If congestive heart failure is due to failure of myocardial fibers, the essentials of pathophysiology are as follows: (1) the velocity of myocardial fiber contraction varies inversely with the load moved; (2) at any given load, the velocity of contraction can be enhanced by increasing fiber length (heterometric autoregulation), or by sympathetic stimulation (homeometric autoregulation), sympathomimetic drugs, and