Percutaneous Mitral Valve Repair: Outcome Improvement with Operator Experience and a Second-Generation Device

Background and aim: Recent randomized data comparing percutaneous mitral valve repair (PMVR) versus optimal medical treatment in patients with functional MR (FMR) seemed to highlight the importance of the learning curve not only for procedural outcomes but also for patient selection. The aim of the study was to compare a contemporary series of patients undergoing PMVR using a second-generation Mitraclip device (Mitraclip NT) with previous cohorts treated with a first-generation system. Methods: This multicenter study collected individual data from 18 centers between 2012 and 2017. The cohort was divided into three groups according to the use of the first-generation Mitraclip during the first (control-1) or second half (control-2) or the Mitraclip NT system. Results: A total of 545 consecutive patients were included in the study. Among all, 182 (33.3%), 183 (33.3%), and 180 (33.3%) patients underwent mitral repair in the control-1, control-2, and NT cohorts, respectively. Procedural success was achieved in 93.3% of patients without differences between groups. Major adverse events did not statistically differ among groups, but there was a higher rate of pericardial effusion in the control-1 group (4.3%, 0.6%, and 2.6%, respectively
p = 0.025). The composite endpoint of death, surgery, and admission for congestive heart failure (CHF) at 12 months was lower in the NT group (23.5% in control-1, 22.5% in control-2, and 8.3% in the NT group
p = 0.032). Conclusions: The present paper shows that contemporary clinical outcomes of patients undergoing PMVR with the Mitraclip system have improved over time.