Mitral valve relpair and revascularization for ischemic mitral regurgitation: predictors of operative mortality and survival.

Background and aims of the study: Surgery for ischemic mitral regurgitation (IMR) is required in 4-5% of patients subjected to coronary artery surgery, and may be challenging. The study aim was to determine outcome following mitral valve repair and myocardial revascularization for moderate-to-severe IMR. Methods: A total of 102 patients (mean age 68 7 years) underwent mitral valve repair for IMR between 1998 and 2001 at the authors' unit. Among patients, 28 had acute and 74 chronic mitral regurgitation (MR). Valve repair was achieved with an annuloplasty ring in all 102 patients, while 99 underwent concomitant myocardial revascularization. Preoperatively, 69 patients had MR grade III-IV, 62 had CCS angina class III-IV, 59 were in NYHA class III-IV, 81 had impaired left ventricular function, and 10 were in cardiogenic shock. Follow up was 100% complete (mean 14 7 months; range: 0-38 months). Results: Overall operative mortality was 8.8% (n = 9) (17.8% for acute IMR, 5.4% for chronic, p = 0.048). On multiple logistic regression analysis, cardiogenic shock (p = 0.028) was the only significant risk factor for operative death. There were 11 late deaths. Kaplan-Meier survival at one and three years was 82 +/- 4% and 79 +/- 4%, respectively. On Cox proportional hazards regression model, preoperative left ventricular end-systolic diameter (LVESD) >4.5 cm (p = 0.01) and NYHA class III-IV (p = 0.02) were independent adverse predictors of survival. Three patients required reoperation. Kaplan-Meier three-year freedom from reoperation was 97 +/- 2%. Conclusion: Surgery for IMR carries a considerable, but acceptable, operative risk and provides satisfactory freedom from reoperation and mid-term survival. Cardiogenic shock before surgery is the major determinant of an unfavorable in-hospital outcome. LVESD >4.5 cm and poor preoperative NYHA status limit the probability of late survival. The study results support early surgical intervention for IMR, before ventricular dilatation occurs.