August 16, 2026JACC Advances0 citationsOpen Access
View Full PaperMitral Transcatheter Edge-to-Edge Repair in Ventricular Functional Mitral Regurgitation and Very Severe Left Ventricular Dysfunction
Key Result
In patients undergoing M-TEER for functional MR, LVEF <20% versus 20-40% did not significantly increase the 1-year risk of death or heart failure hospitalization (HR 1.24; 95% CI 0.82-1.88).
Study Design
Type
Cohort (n=1,538)
Structured PICO
Does mitral transcatheter edge-to-edge repair (M-TEER) have similar safety and efficacy in patients with functional MR and LVEF <20% compared to those with 20%≤ LVEF ≤40%?
P
Population
1,538 patients with functional mitral regurgitation and LVEF ≤40% undergoing mitral transcatheter edge-to-edge repair, followed for 1 year.
E
Exposure
Mitral transcatheter edge-to-edge repair (M-TEER) in patients with LVEF <20%
C
Comparator
Mitral transcatheter edge-to-edge repair (M-TEER) in patients with 20%≤ LVEF ≤40%
O
Outcome
Composite of all-cause death and heart failure (HF) hospitalization at 1 yearcomposite
M-TEER is feasible and provides meaningful symptomatic improvement in patients with functional MR and very severe LV dysfunction (LVEF <20%), with comparable 1-year rates of death or HF hospitalization to those with LVEF 20-40%, despite higher baseline cardiovascular mortality risk.
Main Result
Hazard Ratio: 1.24 (95% CI 0.82–1.88)
Abstract
BACKGROUND: Patients with functional mitral regurgitation (MR) and very severe left ventricular (LV) dysfunction (LV ejection fraction LVEF <20%) have been largely excluded from randomized trials of mitral transcatheter edge-to-edge repair (M-TEER), leaving a substantial knowledge gap regarding the role of M-TEER in this high-risk population. OBJECTIVES: This study aimed to evaluate the safety, feasibility, and 1-year outcomes of M-TEER in patients with functional MR and LVEF <20%. METHODS: The OCEAN (Optimized Catheter Valvular Intervention)-Mitral registry prospectively enrolled patients undergoing M-TEER. Among patients with functional MR and LVEF ≤40% (n = 1,538), outcomes were compared between those with LVEF <20% (n = 103) and 20%≤ LVEF ≤40% (n = 1,435). The primary endpoint was the composite of all-cause death and heart failure (HF) hospitalization at 1 year. Secondary endpoints included cardiovascular (CV) death and procedural outcomes. RESULTS: Acute procedural success was similar between groups (n = 103 100%, LVEF <20% vs n = 1,390 97%, 20%≤ LVEF ≤40%), with comparable residual MR and postprocedural transmitral pressure gradients. In-hospital mortality did not differ by LVEF category (n = 5 5% vs n = 58 4%). Both groups showed significant improvement in NYHA functional class at 1 year, although functional status remained worse in patients with LVEF <20%. After adjustment, the primary endpoint did not differ significantly between groups (LVEF <20% vs 20%≤ LVEF ≤40%; HR: 1.24; 95% CI: 0.82-1.88). However, LVEF <20% was independently associated with higher CV mortality (HR: 2.00; 95% CI: 1.08-3.68). CONCLUSIONS: In patients with ventricular functional MR and LVEF <20%, M-TEER was feasible and associated with meaningful symptomatic improvement without excess risk of death or HF hospitalization, although CV mortality remained higher, likely reflecting advanced myocardial disease.