Postprocedural trans-mitral gradient in patients with degenerative mitral regurgitation undergoing mitral valve transcatheter edge-to-edge repair

Background: The relationship between high postprocedural mean gradient (ppMG) and clinical events following mitral valve transcatheter edge-to-edge repair (MV-TEER) in patients with degenerative mitral regurgitation (DMR) is still debated. Aim: The purpose of this study was to evaluate the effect of elevated ppMG after MV-TEER on clinical events in patients with DMR at 1-year follow-up. Methods: The study included 371 patients with DMR treated with MV-TEER enrolled in the “Multi-center Italian Society of Interventional Cardiology (GISE) registry of trans-catheter treatment of mitral valve regurgitation” (GIOTTO) registry. Patients were stratified in tertiles according to ppMG. Primary endpoint was a composite of all-cause death and hospitalization due to heart failure at 1-year follow-up. Results: Patients were stratified as follows: 187 with a ppMG ≤ 3 mmHg, 77 with a ppMG > 3/=4 mmHg, and 107 with a ppMG > 4 mmHg. Clinical follow-up was available in all subjects. At multivariate analysis, neither a ppMG > 4 mmHg nor a ppMG ≥ 5 mmHg were independently associated with the outcome. Notably, the risk of elevated residual MR (rMR > 2+) was significantly higher in patients belonging to the highest tertile of ppMG (p = 0.009). The association of ppMG > 4 mmHg and rMR ≥ 2+ was strongly and independently associated with adverse events (hazard ratio: 1.98; 95% confidence interval: [1.10–3.58]). Conclusions: In a real-world cohort of patients suffering DMR and treated with MV-TEER, isolated ppMG was not associated with the outcome at 1-year follow-up. A high proportion of patients showed both elevated ppMG and rMR and their combination appeared to be a strong predictor of adverse events.