Transcatheter edge-to-edge repair vs medical therapy in atrial functional mitral regurgitation: a propensity score-based comparison from the OCEAN-Mitral and REVEAL-AFMR registries

Abstract

Background and aims: Atrial functional mitral regurgitation (AFMR) commonly affects elderly and frail individuals. The prognostic impact of transcatheter edge-to-edge repair (TEER) for AFMR has not been investigated.

Methods: Patients with AFMR who underwent TEER were selected from the OCEAN-Mitral registry, and medically managed controls were selected from the REVEAL-AFMR registry, using an identical AFMR definition. The primary endpoint was a composite of all-cause mortality and heart failure hospitalization. The secondary endpoint was all-cause mortality.

Results: A total of 1081 patients (mean age 80.1 ± 8.2 years, 60.5% female) with moderate or severe AFMR were included, of whom 441 underwent TEER and 640 remained on medical treatment. Overlap weighting based on the propensity score yielded well-balanced characteristics (n = 441 vs 640; all standardized mean differences <0.01), where TEER was associated with a lower incidence of the primary (hazard ratio [HR] 0.65, 95% confidence interval [CI] 0.43-0.99, P = .044) and secondary endpoints (HR 0.58, 95% CI 0.35-0.99, P = .044). In an exploratory subgroup analysis, favourable outcomes might be pronounced in patients with ≤mild residual AFMR after TEER, while event rates in those with ≥ moderate residual AFMR were comparable with the medication group. As sensitivity analyses, inverse probability of treatment weighting (n = 158 vs 173), propensity score matching (n = 104 vs 104), and multivariable Cox regression (n = 441 vs. 640) all confirmed favourable associations of TEER with both endpoints.

Conclusions: In real-world data, TEER for patients with moderate or severe AFMR were associated with a lower incidence of adverse events compared with medical treatment.

Keywords: Atrial functional mitral regurgitation; Heart failure; Mitral regurgitation; Transcatheter edge-to-edge repair.

Structured Graphical Abstract

Comparison of patients with atrial functional mitral regurgitation treated with transcatheter edge-to-edge mitral valve repair vs medical therapy. CI, confidence interval; HFH, heart failure hospitalization; HR, hazard ratio; IPTW, inverse probability of treatment weighting; MR, mitral regurgitation; TEER, transcatheter edge-to-edge repair.

Figure 1

Adjusted Kaplan–Meier curves for both endpoints. Adjusted Kaplan–Meier curves using overlap weighting for the composite endpoint of all-cause mortality and heart failure hospitalization (A, left) and all-cause death (A, right). Adjusted Kaplan-Meier curves using IPTW for the composite endpoint of all-cause mortality and heart failure hospitalization (B, left) and all-cause death (B, right). Adjusted Kaplan–Meier curves for 1:1 propensity score matching for the composite endpoint of all-cause mortality and heart failure hospitalization (C, left) and all-cause death (C, right). Event-free survival estimates with standard errors are shown for 3 years. The TEER-treated group (blue) consistently demonstrate better outcomes compared with the medically treated group (red). HFH, heart failure hospitalization; HR, hazard ratio; IPTW, inverse probability of treatment weighting; PS, propensity score; TEER, transcatheter edge-to-edge repair

Figure 2

Adjusted Kaplan–Meier curves stratified by residual MR severity at discharge. Adjusted Kaplan–Meier curves stratified by residual MR severity at discharge in the TEER-treated group and the medically treated group for the composite endpoint of all-cause mortality and heart failure hospitalization (A) and all-cause death (B). Patients with mild or less residual MR (green) show significantly better outcomes compared with those with moderate or severe residual MR (blue) and the medically treated group (red). CI, confidence interval; HFH, heart failure hospitalization; HR, hazard ratio; MR, mitral regurgitation

Figure 3

Forest plot of subgroup analysis for all-cause mortality and heart failure hospitalization. Subgroup analyses showing HR with 95% CI for the composite endpoint of all-cause mortality and heart failure hospitalization in TEER-treated vs. medically treated groups. Subgroups include age, sex, MR severity, severity of tricuspid regurgitation, left atrial volume index, and left ventricular diameter. P-values for interaction are provided for each subgroup. LA, left atrium; LV, left ventricle; MR, mitral regurgitation; Paf, paroxysmal atrial fibrillation; TR, tricuspid regurgitation