A Systematic Review and Meta-Analysis of Outcomes Following Mitral Valve Surgery in Patients with Significant Functional Mitral Regurgitation and Left Ventricular Dysfunction.

Background And Aim Of The Study: The surgical correction of functional mitral regurgitation (MR) remains challenging and controversial. The study aim was to systematically review the outcomes of surgical mitral valve repair (MVRpr) and mitral valve replacement (MVR) in patients with significant functional MR and left ventricular (LV) dysfunction.

Methods: A meta-analysis was performed of published data acquired from patients with moderate to severe functional MR and LV ejection fraction (LVEF) <40% who underwent surgical MVRpr or MVR. The data were meta-analyzed across studies using Bayesian hierarchical models when feasible.

Results: The search yielded 36 observational studies. The pooled proportion of operative mortality following MVRpr was 5% (33 studies; 2,231 patients; 95% credible interval (CrI) 4-7%), while that following MVR was 10% (10 studies; 389 patients; 95% CrI 5-18%). For patients undergoing MVRpr, pooled proportions of postoperative cerebrovascular accidents and renal failure were 2% (11 studies; 750 patients; 95% CrI 1-3%) and 9% (11 studies; 756 patients; 95% CrI 5-16%), respectively. The five-year actuarial survival rates following MVRpr across 12 studies ranged from 47% to 78% (median 66%).

Conclusions: In selected patients with significant functional MR and LV dysfunction, surgical MVRpr and MVR can be performed with acceptable intermediate operative mortality risks.