Effect of Atrial Fibrillation and Mitral Valve Gradients on Response to Percutaneous Mitral Valve Repair With the MitraClip System

Both pre-existing atrial fibrillation (AF) and mitral valve pressure gradients (MVPG) created by MitraClip implantation have demonstrated predictive power for unfavorable outcomes. Therefore, we aimed to assess the impact of MVPG following MitraClip on outcomes in patients with and without AF. A total of 200 patients who underwent MitraClip implantation in our institution were enrolled. Echocardiography was obtained before and after the procedure. The primary endpoint of the study was all-cause mortality 1-year after MitraClip implantation. Secondary end points were clinical improvements in NYHA functional class and reduction in MR severity after MitraClip implantation. Two hundred patients (74 ± 10 years, left ventricular ejection fraction 41% ± 14%, logistic EuroSCORE I 21 ± 15) were enrolled into the final analysis. One hundred twelve patients (56%) had pre-existing AF. One-year all-cause mortality was 17% without any differences between patients with or without pre-existing AF. Comparing postprocedural MVPG of surviving and deceased patients, deceased patients with pre-existing AF exhibited significantly elevated postprocedural MVPG compared with surviving patients without AF (4.8 ± 2.1 mm Hg vs 3.6 ± 1.8 mm Hg; p = 0.010). ROC analysis and Kaplan–Meier survival curves identified significantly reduced survival in AF patients with postprocedural MVPG above 4.0 mm Hg (p = 0.011). After MitraClip, a MVPG above 4.0 mm Hg in patients with pre-existing AF was a significant outcome predictor in univariate and multivariate analysis. In conclusion, we identified a high-risk cohort characterized by postprocedural MVPG above 4.0 mm Hg and pre-existing AF predicting poor long-term outcome.