Mitral valve repair versus revascularization alone in the treatment of ischemic mitral regurgitation

BACKGROUND - For patients with ischemic mitral regurgitation (MR), it is not clear whether adjunctive mitral valve (MV) repair at the time of coronary artery bypass graft surgery (CABG) is beneficial. We sought to test the hypothesis that MV repair with CABG is superior to CABG alone in improving MR without increasing operative or long-term mortality. METHODS AND RESULTS - A total of 107 consecutive patients with moderate or severe ischemic MR, as determined by preoperative echocardiography, underwent CABG with concomitant MV repair (repair group, n=50) or CABG only (CABG group, n=57). Degree of MR was graded as none, mild, moderate, or severe by the proximal isovelocity surface area method. The groups were similar with respect to age, gender, baseline New York Heart Association class, ejection fraction, and number of bypass grafts. The repair group had a higher percentage of patients with atrial fibrillation or severe MR than the CABG group. The operative mortality was significantly higher for the repair group (12%) than the CABG group (2%), whereas the 5-year actuarial survival rate of the 2 groups was similar (88%±5% versus 87%±6%). On multivariate logistic regression analysis, older age, higher New York Heart Association class, and atrial fibrillation were independent predictors of operative mortality (P<0.05). Among patients with severe MR, ischemic MR was improved in all patients of the repair group and in 67% of patients in the CABG group (P<0.001), whereas improvement rates in patients with moderate MR were similar in the 2 groups (75% versus 67%, P=NS). CONCLUSIONS - Although MV repair appears to be more effective at reducing ischemic functional MR, CABG alone may be a preferable treatment option for patients with moderate MR and high operative risk factors such as old age or atrial fibrillation.