Influence of concomitant mitral valve intervention on late survival in patients with moderate ischemic mitral regurgitation undergoing surgical revascularization

Objective In patients with moderate ischemic mitral regurgitation (IMR), the impact of concomitant mitral valve intervention at the time of revascularization on late survival remains unclear. The purpose of this study was to compare the lifetime survival of patients with moderate IMR who underwent revascularization alone versus concomitant mitral valve repair or replacement. Methods Retrospective review was performed for 776 consecutive patients, 65 years of age and over with coronary artery disease and moderate IMR who underwent isolated CABG (n = 372), CABG with mitral valve repair (n = 131, CABG+MV repair), or CABG with mitral valve replacement (n = 273, CABG+MV replacement) from 1976 to 2005. Propensity score matching, Kaplan-Meier survival analysis, and Cox-regression were used to compare perioperative and long-term survival. Cross-sectional follow up utilized the CDC National Death Index as well as government and genealogical internet sites, publicly available on-line obituaries, and death notices. Follow up was 98% complete. Results The mean age of the cohort was 74.1±5.8 years with 42.4% female patients. Preoperatively, 54.5% had prior myocardial infarction, 47.7% had a history of congestive heart failure, and 69.1% had an abnormal ejection fraction. Matched patients undergoing CABG or CABG+MV repair had similar incidence of major perioperative morbidity (29.0% vs. 22.1% p = .202) and operative mortality (8.4% vs. 6.1%, p = .475). Late survival was similar between groups ( p = .630). Among matched patients undergoing CABG vs. CABG+MV replacement, those undergoing concomitant replacement had significantly increased perioperative major morbidity (35.2% vs. 20.9%, p < .001) and operative mortality (16.9% vs. 7.7%, p < .001). CABG+MV replacement patients experienced an increased risk of late mortality (HR 1.23, 95% CI 1.01-1.49, p = .035), compared to those undergoing isolated CABG. Conclusions In patients with moderate IMR undergoing surgical revascularization, concomitant mitral valve repair did not demonstrate a clear late survival benefit over isolated CABG, while concomitant mitral valve replacement was associated with increased early and late mortality risk.