Indoramin in severe congestive heart failure.

The acute and chronic effects of indoramin, a new alpha 1-adrenoceptor antagonist with vasodilating properties, were examined in patients with severe congestive heart failure (New York Heart Association class III or IV). In the acute phase, indoramin, 0.2-0.4 mg/kg body weight, was given intravenously to 12 patients, and systemic peripheral resistance, right and left heart pressures, cardiac output, and left ventricular ejection fraction were determined. After indoramin, hemodynamic parameters improved significantly without heart rate changes. At peak effect (10-20 min), there were significant (p less than 0.001) decreases in mean arterial pressure from 105.3 +/- 20.4 to 86.0 +/- 16.8 mm Hg, mean pulmonary artery pressure from 39.4 +/- 10.4 to 21.4 +/- 5.8 mm Hg, total systemic peripheral resistance from 2,738.5 +/- 660 to 1,294.4 +/- 314 dyn s/cm-5, and left ventricular end-diastolic pressure from 35.3 +/- 6.8 to 18.3 +/- 4.7 mm Hg. There were increases (p less than 0.001) in cardiac index from 2.1 +/- 0.73 to 3.3 +/- 0.88 L/min/m2 of body surface area and in left ventricular ejection fraction from 29.0 +/- 6.4 to 42.5 +/- 4.6%. The arteriovenous oxygen difference fell from 36.1 +/- 6.4 to 25.4 +/- 3.8% (p less than 0.001); heart rate did not change significantly (73.3 +/- 5.4 beats/min control; 76.3 +/- 7.9 beats/min after indoramin). Eight patients were studied in the chronic phase. There were no significant changes in systolic or diastolic blood pressure and heart rate in the supine or upright position.(ABSTRACT TRUNCATED AT 250 WORDS)