A new dual-action drug called saterinone combines both alpha-1 blocking vasodilatory property and phosphodiesterase III inhibition--mediated inotropism. A placebo-controlled, randomized, double-blind study was performed in 12 patients with severe congestive heart failure. Either 2 &mgr;g center dot kg center dot min(minus sign1) saterinone (n = 8) or placebo (n = 4) was injected intravenously over 3 h at rest. On-line hemodynamic measurement utilizing intra-arterial blood pressure monitoring and two-dimensional (2D) echocardiography were performed at basal time; then 30, 60, 120 and 180 min after infusion. The parameters measured were blood pressure (mmHg), systemic vascular resistance (SVR dynes center dot cm(5) center dot min(minus sign1)), pulmonary artery pressure (PAP mmHg), mean pulmonary capillary wedge pressure (PCWP mmHg) and cardiac index (CI 1 min/m(2)) using right heart catheterization and end-systolic volume (ESV ml) and end-diastolic volumes (EDV ml), ejection fraction (EF%) using 2D echocardiography. Placebo had no significant effects on any of the parameters (p = NS). Saterinone decreased SVR by 37% (p < 0.001), PAPm by 24% (p < 0.05), PCWP by 35% (p < 0.05), ESV by 27% (p < 0.01) and increased CI by 32% (p < 0.05) and EF by 45% (p < 0.05). Saterinone appears to be a potent drug that produces improvements in both cardiac hemodynamics and LV functional parameters. Further study with this interesting agent is indicated.