Functional Mitral Regurgitation and Transcatheter Mitral Annuloplasty

I n this issue, Schofer and colleagues present findings from the Carillon Mitral Annuloplasty Device European Union Study (AMADEUS), an uncontrolled multicenter trial in which percutaneous placement of a cinching device in the coronary sinus is used to treat functional mitral regurgitation (MR) of ischemic and nonischemic etiologies. 1 Of 48 patients enrolled, the device was successfully implanted in 30. Major adverse events occurred in 6 (13%) of 46 patients based on intent-to-treat. The severity of MR, based on 4 echocardiography/Doppler measures, decreased between 22% and 32%. There was substantial functional improvement (assessed by New York Heart Association functional class, 6-minute walk test, and the Kansas City Cardiomyopathy Questionnaire) at 1-month and 6-month follow-up. The study is at once exciting and provocative; it is the extrapolation of its results to clinical practice that may be controversial.