Transcatheter Mitral Valve Replacement for Degenerated Bioprosthetic Valves and Failed Annuloplasty Rings.

The risk of recurrent mitral regurgitation after surgical mitral valve repair for ischemic functional mitral regurgitation is 28 % at 10 years. Also, an increasing number of patients with degenerated mitral bioprostheses are seen in daily clinical practice due to a dramatic shift from mechanical to biological bioprostheses over the past few decades. Therefore, it can be anticipated that there will be growing need for therapy options to treat high-risk patients in case of recurrent mitral regurgitation subsequent to surgical mitral valve repair or replacement. Interventional therapy for failing surgical mitral valve replacement and repair is an appealing option in patients who are ineligible for redo surgery. The efficacy and safety of transcatheter mitral valve replacement have been reported in patients with failing mitral rings or degenerated mitral bioprostheses. However, crucial limitations remain, including possible device malpositioning, left ventricular outflow tract obstruction and postprocedural mitral regurgitation. Partially, these complications can be explained by the most frequently used transcatheter heart valves, which are balloon-expanding bioprostheses intended for transcatheter aortic valve implantation that cannot be repositioned. Currently, frequently used approaches for transcatheter mitral valve replacement include retrograde transapical and antegrade transseptal techniques, most often with the use of transcatheter heart valves from the Sapien family (Edwards Lifesciences Inc., Irvine, CA, USA) followed by the mechanical expandable Lotus valve (Boston Scientific, Marlborough, MS, USA). Anecdotal reports have described the application of self-expandable transcatheter heart valves (Centera; Edwards) or dedicated transcatheter mitral valve replacement devices. In this report, we give an overview of current interventional techniques, available evidence and reported outcomes for transcatheter mitral valve replacement for degenerated bioprosthetic valves and failed annuloplasty rings.