Effects of droperidol on left ventricular performance in humans.

The action of droperidol on left ventricular (LV) performance was examined before angiography in nine unpremedicated patients undergoing cardiac catheterization for stable uncomplicated coronary artery disease. Using local anesthesia, catheters were placed in the left ventricle, thoracic aorta, and pulmonary artery. Cardiac output (CO) and LV pressure derivatives were measured before and 2, 5, 10, 15, and 20 min after intravenous administration of 0.15 mg/kg droperidol. Droperidol administration induced a time-dependent decrease of mean arterial pressure (MAP) (significant at 2, 10, 15, and 20 min) and of cardiac index (CI) (significant at 15 and 20 min) with maximal changes observed at 20 min (-14 per cent for MAP and -15 per cent for CI). in addition, the following changes occurred in variables related to LV performance: 1) a transient increase in both heart rate (HR) (2, 5, and 10 min) and maximum rate of rise of left ventricular pressure/instantaneous left ventricular pressure (dP . dt-1 max . IP-1) (+ 15 per cent for HR and + 14 per cent for dP .dt-1 max . IP-1); 2) an early (2 min) and sustained (5, 10, 15, and 20 min) decrease of left ventricular end-diastolic pressure (LVEDP), maximum at 5 min (-30 per cent); 3) no change in systemic vascular resistance (SVR). This study shows that the fall in MAP which occurs after intravenous administration of clinical doses of droperidol is primarily due to decreased CO, secondary to decreased LVEDP and not to changes in cardiac contractility and in SVR.