Background: Approximately 50% of patients with severe mitral regurgitation (MR) referred for surgery have prohibitive surgical risk. MitraClip (Abbott Vascular) is an alternative therapy option in these patients. The aim of this study is to evaluate mid-term outcome in patients who underwent MitraClip implantation.
Methods: All consecutive patients with ≥2+ MR and high risk for conventional surgical therapy who underwent MitraClip implantation at our unit were included in the analysis. The primary endpoint was all-cause mortality and secondary endpoint was heart failure rehospitalization.
Results: From October 2008 to December 2016, a total of 162 patients underwent MitraClip procedure at our unit. The mean follow-up duration was 819.8 ± 671.1 days. Acute procedural success was achieved in 141 of 162 patients (87.0%) and was not significantly different between primary and secondary MR patients (P=.09). Mortality rates were 14.4%, 28.7%, 38.7%, and 49.3% at 1 year, 2 years, 3 years, and 5 years, respectively. Rehospitalization rates for heart failure were 21.7%, 34.3%, 44.2%, and 56.6% at 1 year, 2 years, 3 years, and 5 years, respectively. At follow-up, patients exhibited significant improvement in New York Heart Association functional classification (P<.001). On multivariate analysis, baseline left ventricular ejection fraction (LVEF) <30% (odds ratio, 6.62) and baseline MR severity (odds ratio, 3.40) were the strongest predictors of mortality. Primary MR (odds ratio, 0.20) was associated with lower risk of mortality compared with secondary MR.
Conclusions: Treatment of MR with MitraClip results in significant symptomatic improvement with excellent short-term results. However, 5-year mortality was 49.3%; baseline LVEF <30% and MR severity are the strongest predictors of mortality, while primary MR was a predictor for lower risk of mortality when compared with secondary MR.
Keywords: MitraClip; heart failure; mitral regurgitation; mitral valve disease.