Hybrid Mini-Thoracotomy Brugada Syndrome Epicardial Substrate Characterization and Ablation: results from UNCOVER(BrS) Study

Saverio Iacopino^1*Paolo Sorrenti¹Andrea Petretta¹Jacopo Colella¹Alessandro Di Vilio¹Giovanni Statuto¹Gennaro Fabiano¹Giuseppe Campagna¹Gianluca Peluso¹Emmanuel Fabiano²Giuseppe Indellicati¹Simona Brogneri¹Elena Tremoli¹Lorenzo Mantovani¹Giuseppe Speziale³Carlo Savini¹Alberto Tripodi¹

• ¹Maria Cecilia Hospital, Cotignola, Italy
• ²Universita degli Studi Magna Graecia di Catanzaro, Catanzaro, Italy
• ³Ospedale San Carlo di Nancy, Rome, Italy

ABSTRACT Background Data on safety and efficacy of thoracotomy epicardial ablation for Brugada Syndrome (BrS) remain limited. The ongoing UNCOVER(BrS) trial aims to evaluate epicardial substrate homogenization in symptomatic BrS patients. Objective To report the study design and preliminary outcomes of a novel hybrid mini-thoracotomy approach for Brugada substrate mapping and ablation in an initial cohort of BrS patients. Methods This independent, prospective pilot study was conducted at a single center. BrS patients with an implantable cardioverter-defibrillator (ICD) and history of symptomatic events (syncope and/or documented ventricular arrhythmia) were selected for epicardial ablation. Following surgical mini-thoracotomy access, substrate mapping was performed using the Advisor™ HD Grid catheter to identify pathological substrate after ajmaline infusion. Point by point ablation with a contact force catheter was performed to achieve substrate homogenization. Results Between January 2022 and July 2024, six patients were enrolled. No major acute, peri-or post-procedural complications were observed. The procedure acutely eliminated all the pathological substrate, with complete suppression of the Brugada ECG pattern. Procedural efficiency improved over time, with a progressive reduction in procedural duration. At 12-months follow-up, all patients had no symptomatic arrhythmic events. Omnipolar mapping demonstrated superior delineation of the arrhythmic substrate compared to bipolar mapping. Conclusion Epicardial substrate ablation via hybrid mini-thoracotomy approach is technically feasible and preliminarily safe in this initial assessment. No acute and long-term major adverse events were observed. At 12-months follow-up, no symptomatic arrhythmic episodes occurred. Larger studies with extended follow-up are needed to validate these initial findings. Trial registration: ClinicalTrials.gov identifier, NCT05643209, Funded by Abbott Medical.