Disproportionate functional mitral regurgitation predicts a favourable response after MitraClip implant in patients with advanced heart failure. Real-world evidence of a new conceptual framework.

Abstract Introduction Accurate predictors of good clinical response after MitraClip implant in patients with heart failure (HF) are still lacking. Aim of this study was to investigate the role of regurgitant fraction >50% as a marker of disproportionate function mitral regurgitation (FMR) in identifying best responders to Mitraclip. Methods and results Data from 58 advanced HF patients (age 66 ± 8 years, 81% males, 63% NYHA class IV, LV ejection fraction (EF) 25.5 ± 5.5%) with disproportionate and proportionate FMR who underwent successful MitraClip implant were analyzed. After MitraClip all patient achieved mild (≤ 2+/4+) MR. During 12-month follow-up 18 patients (31%) had a major adverse cardiac event (MACE, i.e. cardiac death, urgent LVAD implant or heart transplantation, HF hospitalization). Disproportionate FMR (n = 48, 83%) was associated with a better clinical outcome (p = .003) while regurgitant volume and EROA were not. TAPSE ≤14 mm was associated with worse outcome (p = .018). At multivariable analysis only disproportionate MR and TAPSE ≤14 mm showed a significant association with MACE (p = .017 and p = .02, respectively). A reverse left ventricular remodeling (i.e., reduction on LV end-diastolic diameter and end-diastolic volume) was achieved only in the disproportionate FMR group. Conclusions In conclusion, disproportionate FMR assessed by regurgitant fraction and RV dysfunction assessed by TAPSE may help the selection of HF patients candidates for MitraClip therapy.