Prognostic Value of Pre-operative Atrial Fibrillation in Patients With Secondary Mitral Regurgitation Undergoing MitraClip Implantation

Limited data are available regarding the independent prognostic role of preoperative atrial fibrillation (AF) after transcatheter mitral valve repair with MitraClip. We sought to evaluate the impact of preoperative AF in patients with heart failure (HF) and concomitant secondary mitral regurgitation (MR) after MitraClip treatment. The study included 605 patients with significant secondary MR from a multicenter international registry. Patients were stratified into 2 groups according to the presence or absence of preoperative AF. Primary end point was 5-year overall death, secondary end points were 5-year cardiac death and first re-hospitalization for HF. To account for baseline differences, patients were propensity score matched 1:1. The overall prevalence of preoperative AF was 44%. At 5-year Kaplan-Meier analysis, compared with patients without AF, those with AF had significantly more adverse events in term of overall death (67% vs 43%; HR 1.84, log-rank p <0.001) and cardiac death (56% vs 29%; HR 2.11, log-rank p <0.001) and re-hospitalization for HF (63% vs 52%; HR 1.33, log-rank p=0.048). Multivariate analysis identified AF as independent predictor of worse outcome in term of primary end point (HR 1.729, 95% C.I. 1.060 to 2.821; p=0.028). After propensity score matching, patients with AF had higher rates of death and cardiac mortality but similar rates of re-hospitalization for HF. In conclusion, in patients with HF undergoing MitraClip treatment for secondary MR, preoperative AF is common and an unfavourable predictor of 5-year death and cardiac death. However, AF did not affect the frequency of re-hospitalization for HF.