Relation of Residual Mitral Regurgitation and Gradient Following Mitral Valve Transcatheter Edge-to-Edge Repair

BACKGROUND: Residual mitral regurgitation (rMR) ≤1+ has been associated with improved 1-year outcomes after mitral valve transcatheter edge-to-edge repair, regardless of the mean mitral pressure gradient (MPG). Prior evidence is limited to 30-day echocardiographic follow-up and patients treated with the MitraClip (Abbott Structural Heart). Whether rMR and MPG assessed at discharge are associated with outcomes after PASCAL mitral valve transcatheter edge-to-edge repair (Edwards Lifesciences) remains unknown. METHODS: REPAIR (Registry of Pascal for Mitral Regurgitation) is an investigator-initiated, multicenter registry including all consecutive patients treated with PASCAL mitral valve transcatheter edge-to-edge repair. Based on discharge echocardiography, patients were stratified into 4 groups: optimal (rMR ≤1+, MPG <5 mm Hg), MPG-suboptimal (rMR ≤1+, MPG ≥5 mm Hg), rMR-suboptimal (rMR ≥2+, MPG <5 mm Hg), and dual-suboptimal (rMR ≥2+, MPG ≥5 mm Hg). The primary end point was 1-year mortality. RESULTS: Among 2172 patients (median follow-up, 463 days [Q1–Q3, 357–815]), 59.4% were classified as optimal, 12.2% MPG-suboptimal, 21.3% rMR-suboptimal, and 7.0% dual-suboptimal. One-year mortality differed significantly across groups ( P <0.001), with the lowest rate in the optimal (8.7% [95% CI, 6.8%–10.5%]) and highest in the dual-suboptimal group (20.1% [95% CI, 12.0%–27.4%]; P Bonferroni <0.001). rMR ≤1+ was associated with lower 1-year mortality (hazard ratio, 0.54 [95% CI, 0.37–0.74]; P <0.001) and remained significant, independent of dichotomized (MPG, <5 versus ≥5 mm Hg) or continuous MPG. Dichotomized MPG was not significantly associated with 1-year mortality (hazard ratio, 0.73 [95% CI, 0.51–1.04]; P =0.078), whereas continuous MPG was (hazard ratio per mm Hg increase, 1.10 [95% CI, 1.00–1.21]; P =0.048) with a trend after adjusting for rMR ≤1+ (adjusted hazard ratio per mm Hg increase, 1.07 [95% CI, 0.98–1.18]; P =0.145). No interaction was observed between rMR ≤1+ and dichotomized/continuous MPG (both P interaction >0.450). CONCLUSIONS: Discharge rMR ≤1+ is independently associated with lower 1-year mortality after PASCAL mitral valve transcatheter edge-to-edge repair. Although MPG was not independently associated, modestly elevated gradients may be acceptable when rMR ≤1+ is achieved, but should still warrant clinical attention. REGISTRATION: URL: https://www.drks.de ; Unique identifier: DRKS00033959.