Outcomes in Patients With High Transmitral Gradient After Mitral Valve Transcatheter Edge-to-Edge Repair for Mitral Regurgitation

Despite being highly effective in reducing residual mitral regurgitation and improving outcomes, mitral valve transcatheter edge-to-edge repair (MV-TEER) may be associated with high postprocedural residual mitral gradient (rMG). Conflicting results have been reported regarding the relation between rMG and adverse events. This study aimed to evaluate the predictors and the impact of elevated rMG after MV-TEER on clinical events in patients with functional mitral regurgitation (FMR) at 2 years follow-up. We selected a cohort of 864 patients with FMR who were treated with MV-TEER enrolled in the multicentre Italian Society of Interventional Cardiology (GISE) registry of transcatheter treatment of mitral valve regurgitation (GIOTTO). Patients were stratified into tertiles according to rMG. The primary clinical end point was a composite of all-cause death and hospitalization because of heart failure at 2-year follow-up. Overall, 269 patients (31.5%) with an rMG <3 mm Hg, 259 (30.3%) with an rMG ≥3/<4 mm Hg, and 326 (38.2%) with an rMG ≥4 mm Hg were considered. At multivariate logistic regression, ischemic FMR etiology, baseline MG, and the number of implanted clips were independent predictors of an rMG ≥4 mm Hg. Clinical follow-up was available in 570 patients (63.2%). Patients with an rMG ≥4 mm Hg experienced higher rates of the composite end point than patients of the other tertiles (51.1%, vs 42.3% vs 40.8% log-rank test: p = 0.033). In multivariate Cox's regression, both rMG ≥4 mm Hg (hazard ratio 1.54, 95% confidence interval 1.14 to 2.08) and residual mitral regurgitation ≥2+ (hazard ratio 1.36, 95% confidence interval 1.01 to 1.83) were independent predictors of adverse events at 2-year follow-up. In conclusion, we demonstrated that real-world patients who underwent MV-TEER who show an rMG ≥4 mm Hg are at higher risk of death or hospitalization because of heart failure during a 2-year follow-up. Further studies will be needed to confirm our results.