Comparative vasoactive therapy for heart failure.

Dopamine and dobutamine increase myocardial contractility by beta-adrenergic stimulation. Both agents provide significant support for decompensating congestive heart failure (CHF) patients. At the same time, both agents can have significant adverse effects. In 1981, it was reported that amrinone, a bipyridine derivative, produced hemodynamic changes similar to those of dobutamine. To confirm these results, the hemodynamic and clinical effects of amrinone were compared with those of dopamine and dobutamine in 15 consecutive patients with CHF. Although each drug improved maximal cardiac index to a similar extent, dopamine did not decrease pulmonary artery wedge pressure and caused a greater increase in heart rate. Dobutamine and amrinone conferred similar hemodynamic benefits: cardiac index improved from 2.4 +/- 0.2 to 3.4 +/- 0.2 liters/min/m2 with dobutamine and from 2.1 +/- 0.2 to 3.2 +/- 0.2 liters/min/m2 with amrinone. Pulmonary artery wedge pressure decreased similarly: from 19 +/- 2 to 13 +/- 1 mm Hg with dobutamine and from 18 +/- 2 to 12 +/- 1 mm Hg with amrinone. Dobutamine and amrinone produced similar modest decreases in mean arterial pressure and increments in heart rate. Dopamine was poorly tolerated; 5 patients developed such severe adverse reactions that this drug was discontinued prematurely. Dobutamine and amrinone were much better tolerated. Although amrinone caused asymptomatic tachycardia (heart rate increase greater than 20% over baseline) in 4 patients, no patient developed an adverse reaction warranting its premature termination.