Godino C, Sisinni A, Pivato CA, et al. - In view of limited data concerning the independent prognostic value of preoperative AF after transcatheter mitral valve repair with MitraClip, researchers here examined the impact of preoperative atrial fibrillation (AF) in patients with heart failure (HF) and concomitant secondary mitral regurgitation (MR) after MitraClip treatment. From a multicenter international registry, 605 patients with significant secondary MR were assessed. Preoperative AF was prevalent in 44%. At 5-year Kaplan-Meier analysis, significantly more adverse events were observed in terms of overall death and cardiac death and re-hospitalization for HF among patients with AF vs those without AF. Findings overall suggest that patients with HF undergoing MitraClip treatment for secondary MR frequently exhibit preoperative AF and indicate preoperative AF to be an unfavourable predictor of 5-year death and cardiac death. However, no effect of AF on the frequency of re-hospitalization for HF was evident.