Transcatheter Mitral Valve Therapy: Repair and Replacement

Purpose of ReviewIn this paper, we discuss the salient clinical and anatomic challenges in percutaneous mitral valve repair and replacement.Recent FindingsThe mitral valve is complex structure and understanding its intricacies and anatomic relationships to surrounding structures (i.e., aortic valve and papillary muscles) is central to delivery of therapies. Part of the complexity is treatment of primary and secondary mitral regurgitation, where in primary regurgitation the valve is the primary issue and treatment should be curative or treatment of secondary mitral regurgitation, where the valve is subject to distortion due to adverse myocardial remodeling (i.e. myocardial infarction or dilated cardiomyopathy). Percutaneous edge-to-edge mitral valve repair remains the current standard of non-surgical therapy and while thousands of patients have been treated, limitations related to leaflet calcification, mitral valve annular area, and large flail gaps remain as challenges in using this device. Alternative annuloplasty-based devices can work either through implanting anchors in the annular tissue or via the coronary sinus. New artificial chordae tendineae are a promising therapy for flail leaflets. Transcatheter mitral valve replacement has even more challenges with respect to potential left ventricular outflow tract obstruction, valve fixation, and the requirement for oral anti-coagulation for thromboprophylaxis.SummaryTranscatheter therapy for repair or replacement of the mitral valve remains in early stages, and delineating a strategy for selecting the proper devices and patients for either repair or replacement will be a major focus in the years forthcoming.