Combined Impact of Residual Mitral Regurgitation and Gradient After Mitral Valve Transcatheter Edge-to-Edge Repair

Abstract

Background: Reducing mitral regurgitation (MR) during mitral transcatheter edge-to-edge repair (M-TEER) may come at the cost of increased mitral valve gradient (MVG). The combined impact of residual MR and MVG on clinical outcomes after M-TEER is unknown.

Objectives: This study sought to evaluate the impact of postprocedure MR and MVG on clinical outcomes after M-TEER.

Methods: EXPANDed is a pooled, patient-level cohort of the EXPAND (A Contemporary, Prospective Study Evaluating Real-world Experience of Performance and Safety for the Next Generation of MitraClip Devices) and EXPAND G4 studies, which were designed to evaluate real-world safety and effectiveness of the third- and fourth-generation MitraClip TEER Systems. Subjects were categorized by echocardiographic core laboratory (ECL) assessments into 4 groups according to 30-day MR grade and mean MVG: 1) MR ≤1+/MVG <5 mm Hg; 2) MR ≤1+/MVG ≥5 mm Hg; 3) MR ≥2+/MVG <5 mm Hg; and 4) MR ≥2+/MVG ≥5 mm Hg.

Results: A total of 1,723 subjects had evaluable echocardiograms at 30 days: 72% had MR ≤1+/MVG <5 mm Hg, 18% had MR ≤1+/MVG ≥5 mm Hg, 7% had MR ≥2+/MVG <5 mm Hg, and 3% had MR ≥2+/MVG ≥5 mm Hg. MR≤1+ was sustained through 1 year in 93% of patients who achieved 30-day MR≤1+. MVG decreased from 30 days to 1 year in subjects with MVG ≥5 mm Hg (6.7 ± 4.0 to 5.5 ± 2.5 mm Hg MR ≤1+/MVG ≥5 mm Hg and 6.5 ± 1.5 to 5.5 ± 1.7 mm Hg MR ≥2+/MVG ≥5 mm Hg). One-year rates of all-cause mortality and heart failure hospitalization were lower for subjects who achieved MR ≤1+ at 30 days, regardless of MVG.

Conclusions: Reduction of MR to mild or less after M-TEER with the latest-generation MitraClip systems was associated with clinical benefit regardless of MVG.

Keywords: MitraClip; mitral regurgitation; mitral valve gradient; mitral valve repair.