DOI: 10.1161/CIRCEP.114.001607 1 Safety and Feasibility of Closed Chest Epicardial Catheter

2 Background- Permanent coronary artery damage is a hazardous complication of epicardial radiofrequency ablation. Irreversible electroporation (IRE) is a promising non-thermal ablation modality able to create deep myocardial lesions. We investigated the effects of epicardial IRE on luminal coronary artery diameter and lesion depth. Methods and Results- In 5 pigs (60-75 kg), the pericardium was exposed using surgical subxiphoidal epicardial access. A custom deflectable octopolar 12 mm circular catheter with 2 mm ring electrodes was introduced in the pericardium via a steerable sheath. After coronary angiography (CAG), the proximal, mid and distal LAD and RCx arteries were targeted with a single cathodal 200 joules application. CAG was repeated after IRE and after 3 months follow-up. Using quantitative CAG, the minimal luminal diameter at the lesion site was compared to the average of the diameters just proximal and distal to that lesion. Intimal hyperplasia and lesion size were measured histologically. CAG directly post-ablation demonstrated short-lasting luminal narrowing with normalization in the targeted area, suggestive of coronary spasm. After