Comparative hemodynamic effects of intravenous digoxin and enoximone in severe chronic heart failure

In order to compare the acute hemodynamic effects of digoxin (0.01 mg/kg) and enoximone (1 mg/kg), a phosphodiesterase inhibitor inotropic agent, in severe chronic congestive heart failure, 8 patients (male, mean age 56.7 years, sinus rhythm) were investigated with a randomized cross-over study. Peak effect of enoximone (30 min) in comparison to that of digoxin (90 min) resulted in a similar reduction of left-ventricular filling pressure (-27 vs. -28%) and mean pulmonary artery pressure (-23 vs. -24%). Pulmonary (-39 vs. -16%; p < 0.01) and systemic vascular resistance (-27 vs. -4%; p < 0.001) were significantly lowered by enoximone. Cardiac index (+30 vs. +6%; p < 0.001) and heart rate (+11 vs. -3%; p < 0.05) were increased significantly more by enoximone than by digoxin. Since enoximone resulted in an enhancement of cardiac performance greater than that produced by digoxin, enoximone could be a useful and powerful substitute for digoxin in the acute therapy of severe chronic congestive heart failure with sinus rhythm.