Effects of flunitrazepam on left ventricular performance, coronary haemodynamics and myocardial metabolism in patients with coronary artery disease.

The effects of flunitrazepam 15 micrograms kg-1, on left ventricular (LV) performance, coronary sinus blood flow (CSBF), myocardial oxygen uptake and myocardial lactate balance were studied in nine patients with coronary artery disease undergoing cardiac catheterization. Flunitrazepam produced a decrease in mean aortic pressure (MAP) and in systemic vascular resistance (SVR) with maximal changes from control value observed at 15 min for MAP and at 5 min for SVR. No change in cardiac index was observed. The following changes in variables related to LV performance were observed: (1) a transient increase in heart rate and left ventricular contractility (Vmax); (2) a sustained decrease of left ventricular end-diastolic pressure, maximum at 15 min. Myocardial oxygen consumption was decreased at 15 min but CSBF did not change, whereas total coronary vascular resistance was decreased. Since myocardial lactate extraction was increased and no change in ECG was observed, a coronary steal induced by coronary vasodilatation did not appear to take place.