EVALUATION OF RIGHT VENTRICULAR FUNCTION BY MEANS OF RIGHT VENTRICULAR END-SYSTOLIC PRESSURE-VOLUME RELATIONSHIP (RV Emax) DURING LEFT HEART BYPASS IN DOGS

Abstract

To assess the effect of left heart bypass on right ventricular contractility, we evaluated right ventricular function using right ventricular end-systolic pressure-volume relationship (RV Emax) during left heart bypass in eight open chest dogs. The left heart bypass (from the left atrium and the left ventricular apex to the descending aorta) was performed with a Bio-Pump, and RV Emax was compared at various degrees of assisted flow ratio, defined as bypass flow divided by pulmonary arterial flow. RV Emax was significantly decreased at 75% and 100% assisted flow ratio compared to the control (0% assisted flow ratio). This shows that right ventricular contractilty was impaired during left heart bypass.