Valve-in-valve/valve-in-ring transcatheter mitral valve implantation vs. redo surgical mitral valve replacement for patients with failed bioprosthetic valves or annuloplasty rings: A systematic review and meta-analysis

Background: Valve-in-valve (ViV)/valve-in-ring (ViR) transcatheter mitral valve implantation (TMVI) is a less invasive alternative to redo surgical mitral valve replacement (SMVR). To further verify its feasibility, we aimed to appraise early clinical outcomes after either ViV/ViR TMVI or redo SMVR for failed bioprosthetic valves or annuloplasty rings, as a comparison of long-term follow-up results are not available for these procedures. Methods: We systematically searched PubMed, Cochrane Controlled Trials Register, EMBASE, and Web of Science to identify studies that compared ViV/ViR TMVI and redo SMVR. Fixed- and random-effects meta-analyses were used to compare the early clinical results between these two groups. Results: A total of 3,890 studies published from 2015 to 2022 were searched, and ten articles comprising 7,643 patients (ViV/ViR TMVI, 1,719 patients; redo SMVR, 5,924 patients) were included. In this meta-analysis, ViV/ViR TMVI significantly improved in-hospital mortality (fixedeffects model: odds ratio [OR], 0.72; 95% confidence interval [CI], 0.57-0.92; P = 0.008) and for the matched populations (fixed-effects model: OR, 0.42; 95% CI, 0.29-0.61; P < 0.00001). ViV/ ViR TMVI also outperformed redo SMVR in 30-day mortality and in rates of early postoperative complications. ViV/ViR TMVI resulted in less time spent in the ICU and hospital, whereas it showed no significant difference in one-year mortality. A lack of comparison of long-term clinical outcomes and postoperative echocardiographic results are important limitations of our results. Conclusions: ViV/ViR TMVI is a reliable alternative to redo SMVR for failed bioprosthetic valves or annuloplasty rings as a result of lower in-hospital mortality, higher 30-day survival, and lower early postoperative complication rates, although there is no significant difference in 1-year mortality.