Transcatheter Mitral Valve Replacement: Rationale and Current Status.

Mitral regurgitation (MR) is the most prevalent form of moderate or severe valve disease in the developed world. MR can result from impairment of any part of the mitral valve apparatus and is classified as primary (disease of the leaflets) or secondary (functional). The presence of at least moderate MR is associated with increased morbidity and mortality. With the goal of avoiding the risks of traditional surgery, transcatheter mitral valve therapies have been developed. The current transcatheter repair techniques are limited by therapeutic target and incomplete MR reduction, and thus transcatheter mitral valve replacement (TMVR) has been pursued. Several devices (both transapical and transseptal) are under development, with both early feasibility and pivotal trials under way. As this field develops, the decision to treat with TMVR will require a heart team approach that takes patient-, disease-, and device-specific factors into account.