Hemodynamic study of intravenous propionyl-L-carnitine in patients with ischemic heart disease and normal left ventricular function.

Propionyl-L-carnitine was given intravenously to ten patients with chronic ischemic heart disease who had normal left ventricular function and had not had a previous myocardial infarction. Subsequently, pulmonary and systemic circulation, left ventricular function, and the relationship between the ventricle and afterload were evaluated. This drug, at a dose of 15 mg/kg, improves ventricular function by easing the load and by enhancing cardiac efficiency. The ejection impedance is reduced with a consequent increase in stroke volume as a result of a) a decrease in systemic and pulmonary resistance and b) an increase in arterial compliance. Arterial pressure is maintained due to an increase in total external heart power. Since the tension time index shows a proportionally smaller increase in the energy requirement, it follows that cardiac efficiency has been improved and ventricle-afterload matching is optimal. These results suggest but do not prove that propionyl-L-carnitine exhibits a positive inotropic property.