[Central hemodynamics of a new positive inotropic substance, adibendan. Data from a dose-finding study].

Central Hemodynamics from the New Positive-inotrope Substance Adibendan/An open dose-finding study We investigated the influence of Adibendan which is a new phophodiesterase inhibitor on central hemodynamics in an open dose-finding study. 10 patients with chronic heart failure NYHA II-IV (mean age 67 +/- 5 years) got Adibendan i.v. A maximum increase in cardiac index from 2.3 +/- 0.5 to 3.2 +/- 0.5 l/min.m2 (p less than 0.001) was seen after a cumulative dosage of 0.916 +/- 0.571 mg at a time interval of 107 +/- 43 min after injection of the first dosage of 0.125 mg. There was a pronounced increase in stroke volume index from 30 +/- 6 to 40 +/- 8 ml/m2 (p less than 0.01). Heart rate raised by 5% which was not significant. Systemic vascular resistance dropped by 30% from 1693 +/- 720 to 1177 +/- 292 dyn.s.cm-5 (p less than 0.05), pulmonary vascular resistance by 39% from 755 +/- 273 to 463 +/- 199 dyn.s.cm-5 (p less than 0.001). Blood pressure and right atrial pressure did not alter. Mean pulmonary artery pressure dropped by 14% from 37 +/- 7 to 32 +/- 11 mmHg. We conclude that Adibendan improves cardiac index markedly and causes a modest decrease in mean pulmonary artery pressure.