Recurrent mitral regurgitation and risk factors for early and late mortality after mitral valve repair for functional ischemic mitral regurgitation

Background. Mortality for patients with coronary artery disease and functional ischemic mitral regurgitation (IMR) remains high regardless of the treatment strategy. Data regarding risk factors, progression of MR, and cause of death in this subgroup are limited. Methods. A retrospective study was performed on 257 consecutive patients undergoing mitral valve repair exclusively for IMR from 1996 to 2005. Potential preoperative and perioperative risk factors for death and postoperative echocardiographic data were recorded. Results. Preoperative echocardiography demonstrated 3+ to 4+ MR in 98.4% (252 of 257). Concomitant coronary artery bypass grafting was performed in 80.9% (208 of 257). Operative mortality was 10.1% (26 of 257). Overall survival by Kaplan-Meier analysis was 68.3% at 3 years and 52.0% at 5 years. Factors associated with late mortality by multivariate analysis include advanced age (relative risk [RR], 1.037; 95% confidence interval [CI], 1.016 to 1.059; p <= 0.001), preoperative dialysis (RR, 3.504; 95% CI, 1.590 to 7.720; p=0.008), and diabetes (RR, 2.047; 95% CI, 1.319 to 3.177; p=0.001). Echocardiographic data at 20 +/- 25 months were available in 57% (147 of 257). Their survival by Kaplan-Meier analysis was 76.4% at 3 years and 65.1% at 5 years with 0 to 2+ MR postoperatively (n=106) vs 61.3% and 35.8% with 3+ to 4+ MR (n=41; p=0.003). Cause of death was available in 72.3% (60 of 83) of late deaths, with 42.2% (35 of 83) attributed to cardiac causes and 30.1% (25 of 83) noncardiac. Conclusions. Mortality for IMR remains high despite surgical management and may be related to risk factors for progression of coronary artery disease. Despite repair, MR progresses in many patients and is associated with poor survival, although more detailed prospective data are needed to characterize this relationship.