Outcomes after transcatheter mitral valve implantation in valve-in-valve, valve-in-ring, and valve-in-mitral annular calcification

Aims: We aimed to evaluate transcatheter mitral valve implantation (TMVI) using predominantly balloon-expandable transcatheter heart valves (THV) in patients with a landing zone for a percutaneously delivered prosthesis. Background: Patients with a degenerated mitral valve bioprosthesis, annuloplasty ring, and mitral annulus calcification (MAC) considered at high surgical risk currently represent a treatment challenge. TMVI is an alternative treatment option. Methods: Retrospective analysis of patients with symptomatic degenerated mitral valve bioprosthesis, or annuloplasty ring, and MAC treated with TMVI between November 2011 and April 2021. Endpoints were defined according to Mitral Valve Academic Research Consortium (MVARC) criteria and included device and procedure success at 30 days as well as mortality at 30 days and 1 year after the procedure. Results: A total of 77 patients underwent TMVI (valve in valve [ViV = 56], valve in ring [ViR = 11], and valve in MAC [ViMAC = 10]). There was a trend toward higher technical success (all = 93.5%, ViV = 96.4%, ViR = 90.9%, ViMAC = 80%, p = 0.06) and lower 30-day (all = 11.7%, ViV = 10.7%, ViR = 9.1%, ViMAC = 20%, p = 0.49) and 1-year mortality (all = 26%, ViV = 23.2%, ViR = 27.3%, ViMAC= 40%, p = 0.36) after ViV and ViR compared to ViMAC. Conclusion: TMVI represents a reasonable treatment option in selected patients with MAC or who are poor candidates for redo mitral valve surgery. Technical success and survival up to 1 year were not significantly dependent on the subgroup in which TMVI was performed.