Predictors of moderate ischemic mitral regurgitation improvement after off-pump coronary artery bypass.

Abstract

The aim of this study was to explore the predictors of improvement of moderate ischemic mitral regurgitation after off-pump coronary artery bypass grafting. A prospective study was performed among 109 patients (aged 66.6 ± 8.6 years, 34.6% were female) with prior myocardial infarction and moderate ischemic mitral regurgitation undergoing off-pump coronary artery bypass grafting. Preoperative and follow-up clinical characteristics and echocardiography data were analyzed, focusing on left ventricular global/regional remodeling and function. Patients were grouped by postoperative ischemic mitral regurgitation at 1 year postoperatively: the improved group with no or mild ischemic mitral regurgitation and the failure group with moderate or severe ischemic mitral regurgitation. Data were compared between the 2 groups to explore the predictors of ischemic mitral regurgitation improvement after off-pump coronary artery bypass grafting. Five patients died within 1 year and were excluded. At the 1-year follow-up, there were 55 patients in the improved group and 49 patients in the failure group. Before surgery, the improved group had smaller left ventricular end-systolic volume, greater left ventricular ejection fraction, greater posterior-inferior volume ratio, and earlier operation timing after infarction than the failure group. Posterior-inferior volume ratio (P < .001), ejection fraction (P = .003), and duration between infarction and operation (P < .001) were independent predictors of preoperative moderate ischemic mitral regurgitation improvement. In selected patients, preoperative moderate ischemic mitral regurgitation was relieved by off-pump coronary artery bypass grafting. Greater ejection fraction, greater posterior-inferior volume ratio, and early operation timing after infarction may predict the improvement of moderate ischemic mitral regurgitation after off-pump coronary artery bypass grafting, suggesting that posterior-inferior regional remodeling, reserved ventricular function, and early revascularization are important to the outcome.