Myocardial energetics and efficiency in patients with idiopathic cardiomyopathy: response to dobutamine and amrinone.

Nine consecutive patients having severer idiopathic dilated cardiomyopathy were studied for their response in ventricular function, coronary sinus blood flow and myocardial oxygen consumption, lactate extraction and efficiency following incremental doses of dobutamine, followed by the combination of dobutamine and the phosphodiesterase inhibitor amrinone. Results, presented as baseline and the response to the peak dose (15μg/kg/min) of dobutamine and to the combination of dobutamine and amrinone (each at 15 μg/kg/min) (differences compared with baseline) were: wedge pressure decreased from 28±7 to 26±8 mm Hg ( p =NS) and to 20±6 mm Hg ( p 2 to 2.80±1.1 L/min/m 2 ( p 2 ( p p p =NS) and to 35±10% with the addition of amrinone ( p p p