Original Article: PDF OnlySilke B; Verma, S P; Midtbo, K A; Reynolds, G; Taylor, S HJournal of Cardiovascular Pharmacology: January 1987 - p 19-25 Free Abstract Summary: The comparative haemodynamic dose-response effects of intravenous (i.v.) amrinone and dobutamine were evaluated in 20 male patients with haemodynamic (pulmonary artery occluded pressure (PAOP) >20 mm Hg) and radiographic left heart failure following a recent myocardial infarction. Following a l-h control period, 10 patients were each randomised to amrinone (800, 1,600, or 3,200 µg/kg/h) or dobutamine (200, 400, or 800 µg/kg/h) sequentially infused for 30 min at each dose level; haemodynamic parameters were recorded at the end of each infusion period. Amrinone reduced systemic arterial blood pressure and vascular resistance index with a moderately increased heart rate; PAOP ( − 10 mm Hg; p <0.01) fell substantially without change in cardiac or stroke work indices. Dobutamine increased systemic arterial blood pressure, heart rate, and stroke work index at an unchanged PAOP; cardiac index (+0.7 L/min/m2; 25%; p <0.01) increased. Systemic vascular resistance index was significantly reduced by both drugs. Thus, dobutamine increased cardiac index at an unchanged PAOP; myocardial stroke work increased. Amrinone had lesser effect on cardiac pumping but reduced PAOP (preload) at an unchanged stroke work. The implications of these differential actions for the clinical therapy of myocardial infarction deserves further evaluation. © Lippincott-Raven Publishers.