Long-Term Outcomes of Patients With Elevated Mitral Valve Pressure Gradient After Mitral Valve Edge-to-Edge Repair.

OBJECTIVES: The aim of this study was to investigate the adverse impact of elevated postprocedural mitral valve pressure gradient (MPG) on outcome in a real-world population of patients with severe mitral regurgitation (MR) who underwent transcatheter mitral valve edge-to-edge repair (TEER). BACKGROUND: TEER has become a routine treatment alternative for patients with severe MR at high surgical risk. The consequences of elevated MPG after TEER have been subject to controversial debates. METHODS: All consecutive patients undergoing TEER for either severe degenerative MR (DMR) or functional MR (FMR) at a high-volume center between September 2008 and January 2020 were prospectively included and followed periodically. Postprocedural MPG by discharge transthoracic echocardiography was considered elevated at ≥5 mm Hg. The primary combined endpoint was death or heart failure rehospitalization after 5 years. RESULTS: A total of 713 patients undergoing TEER (DMR, n = 265; FMR, n = 445) were included. Elevated postprocedural MPG was present in 37.0% of those with DMR (n = 98) and 22.0% of those with FMR (n = 98). In contrast to patients with FMR, 6-minute walk distance did not improve in patients with DMR with elevated MPG. Kaplan-Meier analyses did not demonstrate significant differences for the primary endpoint in patients with DMR (low vs elevated MPG, 67.3% vs 74.4%; P = 0.06) and those with FMR (78.6% vs 74.8%; P = 0.54). After adjustment, elevated MPG was an independent predictor of the primary endpoint in patients with DMR (HR: 1.59; 95% CI: 1.03-2.45; P = 0.034) but not in those with FMR (HR: 0.87; 95% CI: 0.63-1.22; P = 0.43). CONCLUSIONS: Elevated postprocedural MPG is an independent predictor of adverse clinical and functional outcomes in patients with DMR but not in those with FMR.