Transapical transcatheter mitral valve implantation in patients with degenerated mitral bioprostheses or failed ring annuloplasty.

Background: We sought to evaluate the outcomes of transapical transcatheter mitral valve replacement in patients with degenerated mitral bioprostheses or failed mitral ring annuloplasty and high surgical risk for redo mitral valve procedure.

Methods: Between August 2012 and December 2020, 41 consecutive high-risk patients underwent transcatheter mitral 'valve-in-valve' (TM-ViV, n=25) or 'valve-in-ring' (TM-ViR, n=16) implantation at our institution. All procedures were performed in a hybrid operating theater using the SAPIEN XT/3™ or the DIRECT FLOW MEDICAL™ prostheses. Data was collected prospectively according to MVARC criteria.

Results: The logistic EuroSCORE-I was 42.3%±20.5% (mean ± SD), the Society of Thoracic Surgeons (STS) score was 11.9%±10.8%, and the STS/ACC-score was 7.6%±4.2%. Transcatheter mitral valve implantations were successful in all patients (100%). Early echocardiographic examinations showed no obstruction of the left ventricular outflow tract (LVOT), no paravalvular leakage, and only trace transvalvular leakage in eight patients. There was no operative mortality; thirty-day mortality was 9.8%. Survival was 72% at one year and 63% at three years. At two-year follow-up, transvalvular mean pressure gradients were 4.6±1.4 mmHg.

Conclusions: Transapical transcatheter mitral valve-in-valve or valve-in-ring implantation represents a true minimally invasive alternative to surgical redo procedures, especially in high-risk patients with failed bioprosthetic mitral valves or annuloplasty and favorable anatomy.