Transcatheter ablation of supraventricular arrhythmias in patients suffering from hypertrophic cardiomyopathy: a propensity score-based analysis

Abstract Background To date, the prognostic impact of transcatheter ablation (T–Abl) of supraventricular arrhythmias (SA) in HCM patients has not been satisfactorily elucidated. Objectives To assess the impact of T–Abl on clinical outcomes in a large cohort of HCM patients. Methods In this retrospective multicenter study, 570 consecutive HCM patients with SA were enrolled, 425 receiving medical therapy and 145 undergoing T–Abl. 1:1 propensity score matching (PSM) led to the inclusion of 234 patients (117 intervention group, 117 medical group) in the final analysis for endpoint evaluation. The primary outcome was a composite of all–cause mortality, heart transplantation (HT) and worsening heart failure (HF). Additionally, an inverse probability weighted (IPW) model was elaborated. Results At PSM analysis, after a median follow-up of 57.3 months, the primary endpoint occurred in 31 (26.5%) patients in the intervention group vs 38 (32.5%) in the medical group (p=0.871). Thromboembolic strokes and major arrhythmic events in the intervention vs the medical group were 9.4% vs 9.4% (p=0.367) and 5.1 vs 7.7% (p=0.741), respectively. Fewer patients in the intervention vs medical group experienced SA recurrences (64.1% vs 84.6%, p<0.001) and transition to permanent SA patterns (21.4% vs 37.6%, p=0.007). IPW analysis showed consistent results. Severe complications related to T–Abl were uncommon (0.7%). Conclusions At 5–year follow–up, T–Abl does not improve major clinical outcomes in a large cohort of HCM patients. Nevertheless, T–Abl seems to facilitate the maintenance of sinus rhythm and decelerate the progression to permanent SA. Lastly, T–Abl is usually safe in HCM.