[Hemodynamic effects of ARL 115 in left ventricular insufficiency]

ARL 115 has vasodilator and positive inotropic properties which justify its use in heart failure. The effects of this drug were studied in 8 patients with advanced myocardial failure (7 cases of primary cardiomyopathy and 1 case of ischaemic cardiomyopathy) undergoing diagnostic cardiac catheterization, 15 minutes after angiocardiography. The cardiac output pressures were measured and the M mode electrocardiogram was recorded under basal conditions and following an infusion of 1 mg/kg of ARL 115 over 10 minutes. An improvement was observed in 7 cases, with an increase in the cardiac output and a decrease in the left ventricular diastolic pressure (p less than 0.05). There was no significant modification in the heart rate and there were no side effects. In one case, an abrupt fall in the diastolic pressure led to a decrease in the cardiac output. The arterial and venous vasodilator properties were demonstrated in every case, but a positive inotropic action (increase in the dp/dtmax and modification of the end-diastolic pressure: dimension ratio) was demonstrated in only two cases. The absence of positive inotropic action in the 6 other cases could be due to the advanced myocardial deterioration in these patients or to a delay in the positive inotropic effect in relation to the vasodilator effect.