Outcomes After Transcatheter Mitral Valve Replacement According to Regurgitation Etiology.

BACKGROUND Whether transcatheter mitral valve replacement (TMVR) devices perform similarly with respect to the underlying mitral regurgitation (MR) etiology remains unelucidated yet. The aim of the present analysis was to assess outcomes of TMVR according to the MR underlying etiology among the CHoice of OptImal transCatheter trEatment for Mitral Insufficiency Registry (CHOICE-MI) registry. METHODS Out of 746 patients, 229 (30.7%) patients underwent TMVR. The study population was subdivided according to primary, secondary or mixed MR. Patients with mitral annular calcification were excluded. The primary study endpoint was a composite endpoint of all-cause mortality or hospitalisation for heart failure at 1 year. Secondary study endpoints included all-cause and cardiovascular mortality at 1 year, New York Heart Association functional class and residual MR, both at discharge and 1 year. RESULTS The predominant MR etiology was secondary MR (58.4%), followed by primary MR (28.7%), and mixed MR (12.9%). Technical success was similar according to MR etiology as was procedural mortality. Discharge echocardiography revealed residual MR 2+ in 11.3%, 3.7%, and 5.3% of patients with primary, secondary, and mixed MR, respectively (P=0.1). MR elimination was similar in all groups up to the 1-year follow-up. There was no difference in terms of primary combined outcome occurrence according to MR etiology. One-year all-cause mortality was reported in 28.8%, 24.2% and 32.1% of the patients with primary, secondary and mixed MR (P=0.07), respectively. CONCLUSIONS In our study, we did not find differences in short- and 1-year outcomes after TMVR according to MR etiology