Safety and Efficacy of Percutaneous Mitral Valve-in-Valve and Mitral Valve-in-Ring Procedures: Systematic Review and Pooled Analysis of 30 Day and One Year Outcomes

Background: The purpose of this study was to perform a systematic review and pooled analysis to evaluate 30-day and 1-year outcomes of transcatheter mitral valve-in-valve (VIV) and valve-in-ring (VIR) procedures. Data from the Valve-in-Valve Data Registry revealed that there were several safety and efficacy concerns, although procedural success was achieved in most cases. Methods: Studies reporting data on either mitral VIV and/or VIR with at least five patients were pooled using weighted proportional analysis. Results: The 30-day pooled estimate of all-cause mortality in the mitral VIV group was 7%, valve embolization, 5%, stroke, 3%, and major bleeding, 9%. At 1 year the all-cause mortality was 11%, valve thrombosis, 10%, stroke, 6%, and major bleeding, 16%. In the mitral VIR group, the 30-day pooled estimate for all-cause mortality was 8%, renal failure, 11%, valve embolization, 3%, and left ventricular outflow tract obstruction, 10% and at 1 year the all-cause mortality was about 22%. Conclusions: Mitral VIV and VIR procedures are safe and feasible in high risk surgical candidates. The long-term safety and efficacy data beyond 1 year for both mitral VIV and VIR need to be established.