Transcatheter therapies for secondary mitral regurgitation in advanced heart failure: what are we aiming for?

Impact of Frailty on Outcomes After Transcatheter Edge-to-Edge Repair With MitraClip (from the National Inpatient Sample Database)

Transcatheter edge-to-edge repair (TEER) with MitraClip (Abbott, Santa Clara, California) is a frequently chosen method for mitral valve repair for patients at high surgical risk. We investigated the impact of frailty on outcomes of patients who underwent TEER. We reviewed the National Inpatient Sample to identify patients that underwent TEER with MitraClip. Frailty was defined using the Johns Hopkins Adjusted Clinical Groups frailty-defining diagnoses indicator. The primary end point was in-hospital mortality. The secondary end points included blood transfusion, respiratory failure, sepsis, length of stay, and total hospitalization cost. Univariate and multivariate logistic regression analyses were performed to determine any association between frailty and primary or secondary outcomes. From January 2016 to December 2017, 10,055 patients underwent TEER in the United States, and 10.6% of them met the criteria for frailty. The frail group showed increased in-hospital mortality (7.04% vs 1.61%, p <0.001) and respiratory failure (3.75% vs 0.95%, p <0.001). Similarly, the frail group had longer lengths of stay (6 vs 2 days, p <0.001) and higher hospitalization costs ($224.8k vs $180.9k, p <0.001). After multivariable logistic regression analysis, frailty was associated with increased in-hospital mortality (odds ratio [OR] 3.70, 95% confidence interval [CI] 1.91 to 7.18, p <0.001), transfusion (OR 1.85, 95% CI 1.07 to 3.19, p = 0.029), respiratory failure (OR 3.56, 95% CI 1.48 to 8.52, p = 0.005), and sepsis (OR 4.17, 95% CI 1.84 to 9.46, p = 0.001). In conclusion, frailty was present in about 10% of patients who underwent TEER from 2016 to 2017. The presence of frailty was associated with worse in-hospital outcomes and greater resource use.

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.