Abstract 13048: Outcomes of Transcatheter Edge-to-Edge Repair in Hypertrophic Cardiomyopathy: A Patient-Level Meta-Analysis

Abstract

Background: Hypertrophic cardiomyopathy (HCM) is a genetic heart disease, commonly associated with left ventricular outflow tract (LVOT) obstruction and mitral regurgitation (MR). Septal myectomy and alcohol septal ablation are the current treatment options for LVOT obstruction and MR in symptomatic patients who are unresponsive to medical therapy. Recently, transcatheter edge-to-edge repair (TEER) of the mitral valve has been introduced as a new therapeutic alternative for these individuals, but there are insufficient outcome data. Objective: Perform a systematic review and patient-level meta-analysis of the studies reporting the outcomes of TEER in HCM. Methods: Original studies published in English in PubMed and Google scholar were included if ≥1 of the following pre- and post-TEER measures were reported: peak resting or provoked LVOT gradients, MR grade, or New York Heart Association (NYHA) class. Variables were presented as means with 95% confidence intervals. Paired t-test was used to compare variables pre- and post-TEER. A p-value <0.05 was statistically significant. Results: A total of 15 publications reporting the outcomes of 30 patients (mean age 74 years, 45% female, average follow-up of 10 months) were included. Compared to pre-TEER measures, there was a significant reduction in resting LVOT gradient (68.29 vs. 11.76 mmHg), provoked LVOT gradient (119.67 vs. 14.11 mmHg), MR grade (3.52 vs. 1.07), and NYHA class (3.14 vs. 1.38) post-TEER (all p<0.0001) (Figure). However, mean MV gradients increased post-TEER (2.00 vs. 3.55 mmHg, respectively, p=0.0018). There was 1 procedural complication noted in which a patient developed a severe mitral valve (MV) gradient of 10 mmHg after complete leaflet clip closure. This decreased to 6 mmHg when the clips were re-deployed partially open (30°). Conclusion: TEER can be an effective therapeutic option for improving LVOT gradient, MR severity, and NYHA class in patients with obstructive HCM.