Coexisting Mitral Regurgitation Impairs Survival After Transcatheter Aortic Valve Implantation

Background. It remains unclear whether coexisting and untreated mitral regurgitation (MR) affects survival after transcatheter aortic valve implantation (TAVI) for aortic stenosis (AS). To summarize contemporary evidence, we performed the first metaanalysis of adjusted observational studies reporting post-TAVI mortality in patients with various grades of MR. Methods. MEDLINE and EMBASE were searched until February 2015, with a bibliographic review of secondary sources. Eligible studies were observational studies enrolling patients undergoing TAVI for AS and reporting adjusted odds ratios (ORs), hazard ratios (HRs), or both for early (30-day or in-hospital) all-cause mortality, overall all-cause mortality, or both in patients with apparent (significant) versus unapparent (nonsignificant) MR as outcomes. Results. Sixteen eligible studies enrolling a total of 13,672 patients undergoing TAVI for AS were identified and included. Pooled analyses of eight studies (representing 9,356 patients) and 14 studies (representing 7,405 patients) respectively demonstrated a statistically significant increase in early (OR 2.17; 95% confidence interval [CI] 1.50 to 3.14; p < 0.0001) and overall all-cause mortality (HR 1.81; 95% CI 1.37 to 2.40; p < 0.0001) in patients with apparent relative to unapparent MR. The exclusion of any single study from the analyses did not substantively alter the overall results of our analyses, and there was no evidence of significant publication bias. Conclusions. Coexisting and untreated apparent (usually moderate or severe) MR appears to be associated with an increase in both early and overall mortality after TAVI for AS. (C) 2015 by The Society of Thoracic Surgeons