Digitalis therapy for patients in clinical heart failure.

Abstract

The most commonly used preparation of digitalis is digoxin, which is obtained from the leaves of Digitalis lanata , a common flowering plant called “foxglove.” The words digitalis and digoxin in this article are used interchangeably. An exhaustive review published in 19961 cited a large number of references and had detailed data and descriptions of a large number of studies and all early trials. The present article summarizes those data but focuses on and emphasizes data collected since that time. These have been described in detail previously1 and are briefly summarized. ### Inotropic Effects The inotropic effects have been documented in the isolated papillary muscles and in the normal hearts of animals and humans. The inotropic action occurs in both ventricles and in both atria. In the normal heart and in those with coronary artery disease and normal left ventricular (LV) systolic function, with digitalis the LV function curve is moved upward and to the left.1 As a result, LV end-diastolic pressure and LV end-diastolic and end-systolic volumes are reduced, and there is an increase of LV ejection fraction (LVEF).1 ### Patients With Heart Failure In patients with heart failure (HF), digoxin slows the ventricular rate (1) in sinus rhythm because of an improvement in HF and withdrawal of sympathetic stimulation and (2) in atrial fibrillation by increasing parasympathetic tone. The combination of digoxin and carvedilol is superior to digoxin or carvedilol alone.2 ### Peripheral Vessels In normal subjects given intravenous ouabain, there is arterial and venous vasocontriction.3 The vasoconstriction is obviated by administering digoxin slowly over a period of 15 to 20 minutes1; moreover, the vasoconstriction lasts up to 30 minutes. The seminal study of Mason and Braunwald3 showed that in HF, the effects are different. Digitalis produces an increase of blood flow, a decrease of vascular resistance, venodilation, and a …