LAUSR

BACKGROUND Epicardial ablation is occasionally limited by coronary artery (CA) injuries or epicardial fat (EF). OBJECTIVE We aimed to evaluate the anatomical obstacles that prevent ablation of epicardial abnormal potentials (EAPs) in patients with Brugada syndrome (BrS) and to investigate the feasibility of EAP elimination by endocardial right ventricular (RV) ablation. METHODS This study included 16 BrS patients with previous ventricular fibrillation (VF), including 10 with an electrical storm. Data from multidetector computed tomography were assessed, and the proximity of the CA and EF was correlated with EAPs. RESULTS EAPs were present in the epicardial RV outflow tract and RV inferior wall in all and 12 patients (75%), respectively. These EAPs were present within 5 mm of the main body and branches of the right CA in 14 patients (87.5%). However, only 1.4±2.9% of the EAP area was covered with thick EF (≥8 mm). Partial EAP elimination by endocardial RV ablation was feasible in all 10 patients, with 53.3% successful endocardial RV radiofrequency applications for eliminating EAPs. After the procedure, VF remained inducible in 37.5% of the patients. During the 25.1±29.1 months of follow-up, no patients experienced an electrical storm, and VF burden significantly decreased (median VF episodes before and after ablation: 7 and 0, respectively). CONCLUSION EAPs are near the CA in most BrS patients, thereby requiring caution during epicardial ablation, while EF is less of an issue. Endocardial ablation is feasible to eliminate some EAPs and may be combined with epicardial ablation.