Right Ventricular Depression After Cardiopulmonary Bypass for Valvular Surgery

Abstract

Objective: To assess if right ventricular (RV) dysfunction is associated with increased mortality after cardiac surgery.

Design: Post-hoc analysis of a single-center double-blind randomized controlled trial.

Setting: University hospital.

Participants: A total of 120 patients undergoing simple or complex valvular surgery.

Interventions: Patients were randomized to receive intravenous amiodarone or placebo intraoperatively. As secondary analysis, patients were divided into those requiring or not requiring postoperative inotropic agents.

Measurements and main results: After cardiopulmonary bypass (CPB), there were significant increases in heart rate, cardiac index, systolic and mean arterial pressures, central venous pressure and pulmonary capillary wedge pressure with reduction in systemic vascular resistance (p<0.05). Right ventricular end-systolic area became larger in those without inotropes and tricuspid annular plane systolic excursion was reduced in all patients; mitral annular systolic velocities were higher in patients receiving inotropes. Both right- and left-sided Doppler signals were altered significantly after CPB, which may be attributed to increased filling pressure. Inotropic agents were required in 56 patients after CPB (47%). The use of inotropic agents was associated with increased left and right atrial velocities (p<0.05). There were no differences in postoperative complications between groups; however, the number of deaths at 6 years was increased in patients who received inotropes after CPB (p = 0.0247).

Conclusions: The increases in right-sided dimensions after CPB are associated with reduction in RV function and increased biventricular filling pressure, suggesting worsening biventricular function and interventricular dependence. Inotropic medications were associated with unaltered RV dimensions and increased biatrial activity.

Keywords: amiodarone; cardiac surgery; cardiopulmonary bypass; inotropic agents; outcome; right ventricular function; transesophageal echocardiography.