The impact of surgical ventricular restoration on mitral valve regurgitation.

Background: Surgical management of functional mitral regurgitation (MR) in ischemic cardiomyopathy is controversial. Surgical ventricular restoration (SVR) decreases left ventricular volume and may improve MR severity. We assessed the impact of SVR on the degree of MR.

Methods: We retrospectively reviewed patients with ejection fractions (EF) < 0.35 who underwent SVR with coronary artery bypass grafting (SVR+CABG) over a 3-year period. Patients with concomitant mitral valve procedures were excluded. Patients with EF < 0.35 who had CABG alone during the same time period served as control. Mitral regurgitation was graded 0 to 4+ by echocardiogram and ventriculogram. Outcomes included survival, MR grade, and cardiac function.

Results: Thirty-nine patients received SVR+CABG: 3% (1 of 39) had 4+, 10% (4 of 39) had 3+, 51% (20 of 39) had 2+, and 36% (14 of 39) had 0 to 1+ MR. Thirty-five patients with a similar MR distribution underwent CABG alone. Operative mortality was 2.6% for SVR+CABG and 5.7% for CABG patients (p = 0.62). At follow-up, MR grade decreased by 57% (2.24 +/- 0.5 to 1.24 +/- 0.9, p < 0.001) for the SVR+CABG group compared to 12% (2.25 +/- 0.5 to 2.00 +/- 0.9, p = 0.27) for the CABG alone group. SVR+CABG patients had significantly less MR than CABG patients at follow-up (1.24 +/- 0.9 vs 2.00 +/- 0.9, p = 0.007), with 15 patients improving to 0 to 1+ MR postoperatively versus 6 patients in the CABG cohort (p = 0.02). Improvement in postoperative EF was significantly greater after SVR+CABG (0.13% vs 7%, p = 0.04). Three-year survival was 85% for SVR+CABG and 72% for CABG patients (p = 0.39).

Conclusions: SVR+CABG demonstrated greater reduction in MR severity at follow-up than CABG alone. Decreased left ventricular volumes and improved papillary muscle orientation likely contribute to decreased MR after SVR.