Cardiovascular effects of dibutyryl cyclic AMP in patients with congestive heart failure. Comparison with dobutamine and captopril.

To assess the effect of dibutylyl cyclic AMP (DBcAMP) on patients with congestive heart failure (CHF) in comparison with dobutamine and captopril, these three agents were administered to 9 patients with CHF. DBcAMP was infused at a rate of 0.2 mg/kg.min for 30 min, dobutamine was infused at a rate of 8 micrograms/kg.min and captopril 25 mg was administered orally. Hemodynamic and echocardiographic studies were performed before and after administration of each agent. Systolic arterial pressure (SAP) fell with DBcAMP and captopril but rose with dobutamine. Cardiac output (CO) rose and systemic vascular resistance (SVR) fell with each agent but the magnitude of the change was greater with DBcAMP than with the other two agents. Left ventricular end-systolic dimension decreased and percent fractional shortening increased with all these drugs. Comparing DBcAMP and captopril, although the degree of change in CO was closely correlated with that in SVR by captopril, the degree of increase in CO by DBcAMP was more than that expected from the degree of the decrease of SVR. Comparing DBcAMP and dobutamine, SAP and pressure rate product increased with dobutamine, but the former fell and the latter was not changed by DBcAMP. Arrhythmia was not increased by DBcAMP, though it was markedly increased by dobutamine. In conclusion, the magnitude of positive inotropic and vasodilator effect of DBcAMP was equal to or greater than that of dobutamine or captopril. So DBcAMP is thought to be useful for the treatment of CHF.