MDL 17,043: short- and long-term cardiopulmonary and clinical effects in patients with heart failure.

MDL 17,043, an inotropic and vasodilator drug, is believed to have beneficial effects in patients with heart failure. Its short- and long-term hemodynamic and cardiopulmonary effects were studied in 10 patients with New York Heart Association functional class III heart failure who were maintained on digitalis and diuretic drugs. Hemodynamics at baseline study and after 24 hours of oral therapy (four doses of 6 mg/kg) showed increased cardiac output (3.9 +/- 0.7 to 6.1 +/- 1.1 liters/min, p less than 0.05), increased stroke volume (42 +/- 12 to 60 +/- 15 ml, p less than 0.05), decreased systemic vascular resistance (1,564 +/- 326 to 1,009 +/- 296 dynes X s X cm-5, p less than 0.05) but no change in pulmonary capillary wedge pressure (31 +/- 6 to 25 +/- 13 mm Hg, p = NS). Only systemic vascular resistance and arteriovenous oxygen difference were significantly decreased during exercise. When restudied after 5 weeks of therapy, neither cardiac output nor stroke volume showed a sustained increase at rest or during exercise, and effects on systemic vascular resistance and arteriovenous oxygen difference were not sustained at exercise (p = NS). Peak oxygen uptake during exercise was 8.1 +/- 2.5 ml/kg per min at baseline and was not significantly increased either acutely (9.2 +/- 2.4 ml/kg per min, p = NS) or chronically (8.9 +/- 2.2 ml/kg per min, p = NS). Problems of increased ventricular arrhythmias and diarrhea were noted after therapy was begun.(ABSTRACT TRUNCATED AT 250 WORDS)