Hemodynamic effects of sulmazol (ARL-115 BS), a new vasodilator and positive inotropic agent, in patients with cardiogenic shock.

The imidazol-pyridine ARL-115 BS (sulmazol) has both positive inotropic and vasodilatory effects. Its hemodynamic effects were studied in 13 patients with shock after myocardial infarction. All patients required dobutamine or dopamine, while nine were treated with intra-aortic balloon counterpulsation. After a loading dose of 50 mg, sulmazol was administered at 50 mg/h followed by 100 mg/h during 30 or 60 minutes. At the highest dose of sulmazol, cardiac output increased from 4.3 +/- 1.1 to 4.9 +/- 1.5 1/min; systemic vascular resistance decreased from 1405 +/- 473 to 1228 +/- 439 dynes . s . cm-5, while pulmonary capillary wedge pressure decreased from 22 +/- 6 to 17 +/- 7 mm Hg. No changes occurred in heart rate or mean arterial pressure. The effect of sulmazol was greater than the effect of an increased dosage of dobutamine in five patients in whom this was studied. Episodes of supraventricular tachycardia occurred in two patients. No other side effects were observed. The hemodynamic changes caused by sulmazol favour its use in the treatment of acute cardiac failure, and cardiogenic shock.