Meta-Analysis of Relation Between Left Ventricular Dysfunction and Outcomes After Transcatheter Mitral Edge-to-Edge Repair

Randomized controlled trials (RCTs) and observational studies provided conflicting results regarding the role of left ventricular (LV) function on outcomes after transcatheter edge-to-edge repair (TEER). The study aimed to provide a comprehensive assessment of the interplay between severe LV dysfunction and TEER outcomes. Multiple electronic databases, including PubMed, EMBASE, Scopus, Web of Science, and CENTRAL, were searched to identify studies on TEER for secondary mitral regurgitation reporting outcomes stratified for LV ejection fraction <30% and ≥30%. The prespecified primary end points were the composite of all-cause death or heart failure (HF) hospitalization and New York Heart Association (NYHA) class III/IV. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by random-effects models. Multiple sensitivity analyses accounting for baseline characteristics and study design were applied. A total of 6 studies (1,957 patients) with 1 year or 2 years of follow-up were available. Severe LV dysfunction was associated with an increased risk of death or HF hospitalization (OR 1.71, 95% CI 1.14 to 2.57). Conversely, comparable rates of NYHA class III/IV (OR 1.06, 95% CI 0.82 to 1.38) or secondary end points (reinterventions, recurrence of significant secondary mitral regurgitation) were found regardless of the baseline LV function. Subgroup meta-analysis found no difference in the composite primary end point between patients with LV ejection fraction <30% and ≥30% enrolled in RCTs. In conclusion, TEER seems to be associated with higher mortality or HF hospitalization rates in patients with severe LV dysfunction. However, RCTs found no differences between groups. No impact of LV function was found on the risk of NYHA class III/IV or other clinical outcomes.