Transcatheter Mitral Valve Replacement in Failed Bioprosthetic Surgical Valves and Surgical Annuloplasty Rings.

PURPOSE OF REVIEW: Repeat surgery for failed mitral valve prostheses and repairs are fraught with high rates of morbidity and mortality. Therefore, clinicians have evolved transcatheter technology as an alternative therapy. This review serves as an update as the field has moved out of the early learning curve of treating postsurgical mitral valve failures.

RECENT FINDINGS: Mitral valve-in-valve procedures have higher rates of technical success and better in-hospital and 1-year mortality rates than mitral valve-in-ring cases. The higher rates of complications, including left ventricular outflow tract obstruction, paravalvular leak, valve embolization, and need for a 2nd valve, may explain these outcomes. Mitral valve-in-ring procedures have attenuated outcomes as compared to valve-in-valve. Clinicians should be cognizant of the nuanced complexities and the potential for suboptimal outcomes in using balloon-expandable valves for mitral valve-in-ring procedures.