Transcatheter valve-in-valve implantation vs. reoperative mitral valve surgery for failing surgical prosthesis

The incidence of degenerated mitral bioprosthesis is increasing in clinical practice due to a greater use of biological prostheses for mitral valve replacement compared to mechanical valves and increased life expectancy after cardiac surgery. Similarly, mitral valve repair can result in long-term recurrence of mitral valve disease requiring reintervention. Therefore, the number of failing surgical prosthesis or repaired valves will increase over the next years representing a new challenge in the corrective approach in the case of long-term structural valve degeneration. Those patients were generally managed with reoperative mitral valve surgery, but transcatheter interventional therapies, initially considered an option in patients who are ineligible for redo surgery, have been recently associated with excellent outcomes. The efficacy and safety of transcatheter mitral valve procedures have been reported in both failing ring annuloplasty or degenerated mitral bioprosthesis, but the use of non-dedicated devices remains associated with significant severe complications such as device malpositioning or left ventricular outflow tract obstruction requiring emergent conversion to open surgery. Both the careful selection of patients and pre/intra-procedural scheduling are warranted to maximize benefits and reduce issues. This review focuses on emerging transcatheter mitral valve replacement devices as therapeutic options for degenerated mitral bioprosthesis or failed mitral repair. This paper aims to summarize current interventional techniques and available evidence, comparing outcomes between transcatheter technologies and reoperative mitral valve surgery.