Pulsed-field vs thermal catheter ablation of atrial fibrillation in patients with hypertrophic cardiomyopathy

Abstract Background Pulsed-field ablation (PFA) may be beneficial for the treatment of atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM). Objectives To compare the safety and efficacy of PFA and thermal ablation in patients with HCM and AF. Methods From 2016 to 2024, patients with HCM undergoing a first AF ablation using PFA or Thermal ablation (cryoballoon or radiofrequency) were retrospectively included from 3 French and Swiss centers. Freedom from atrial arrhythmia (AA) recurrence at 12-months follow-up was assessed. Results Overall, 10 patients (78% male, median age 60 years, 43% paroxysmal AF) with HCM underwent PFA (n=58), or Thermal ablation (n=51) of AF. In addition to pulmonary vein (PV) isolation, extra-PV ablation was performed in 62% of PFA cases and in 18% of Thermal cases. PFA was associated with shorter procedure times than thermal ablation (81 min [interquartile range (IQR) 60—110) vs 132 min [IQR 75—190], p<0.0001), and with less post-procedural heart failure (n=0 vs. n=4, p=0.03). Freedom from AA recurrence was 57% (95% confidence interval [CI] 46—67) after 12 months. PFA was associated with less atrial arrhythmia recurrence than thermal ablation (adjusted hazard-ratio [HR] 0.46, 95% CI 0.23—0.91, P=0.03). Extra-PV ablation was associated with more sustained AA recurrence with thermal ablation (HR 3.07, 95%CI 1.21—7.82, P=0.02), but not with PFA (HR 1.07, 95%CI 0.35—3.27, P=0.91). Conclusions In patients with HCM and AF, PFA seems to be associated with better safety and efficacy outcomes than thermal ablation.