Mitral Repair for Moderate Ischemic Mitral Regurgitation in Patients with End-stage Ischemic Cardiomyopathy

Objectives For patients with end-stage ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG), the indications for concomitant repair of moderate mitral regurgitation (MR) remain controversial. This study evaluated outcomes of concomitant mitral repair (MVr) for moderate ischemic MR in patients with advanced left ventricular (LV) remodeling and severely impaired LV function undergoing CABG. Methods We retrospectively reviewed 341 patients (mean age 67 ± 9 years) with ischemic cardiomyopathy (LV ejection fraction [LVEF] ≤40%) and less-than-severe MR who underwent CABG. Of these, 108 (32%) underwent concomitant MVr for clinically relevant moderate MR, and 233 (68%) underwent CABG alone for mild or absent MR. All patients had a prior myocardial infarction. The primary endpoint was overall survival. Secondary endpoints included postoperative changes in MR grade and LV function at 1 year. Median follow-up was 4.5 years (interquartile range [IQR]: 2.4–7.3 years). Results Despite higher preoperative surgical risk in the CABG + MVr group (EuroSCORE II: 6.7% vs 2.9%, P<.001), 30-day mortality did not differ between groups (1.9% vs 2.1%, P=.88). Five-year overall survival was 73% vs 77% (log-rank P=.25). At 1 year, the CABG + MVr group demonstrated greater LV reverse remodeling (median LVEDVI reduction: −26% vs −19%, P=.001), higher LVEF (46 ± 13% vs 42 ± 12%, P=.044), and a lower prevalence of significant MR (6% vs 13%, P=.032). Conclusions In patients with advanced ischemic cardiomyopathy and moderate MR, concomitant MVr can be performed with acceptable operative risk and promotes superior LV reverse remodeling. Long-term survival was comparable to patients with non-significant MR who did not require mitral intervention, suggesting that targeted mitral repair may normalize the adverse prognostic impact of moderate ischemic MR.