Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Experimental methods D-PO04 - Poster Session IV (ID 15) Poster

D-PO04-145 - In Vivo Tissue Temperature Distribution During Hotballoon Ablation In A Porcine Model (ID 463)

 S. Nakahara: Nothing relevant to disclose.


Background: Hot balloon ablation has been widely used for pulmonary vein isolation of atrial fibrillation (AF) in Japan. In growing the clinically evidence of the efficacy and safety of hotballoon ablation, the actual tissue temperature of the pulmonary veins (PV) during hotballoon ablation is not fully known.
Objective: To investigate the tissue temperature distribution surrounding the PV tissue during hotballoon ablation by using a porcine model.
Methods: In 7 pigs, a right thoracotomy was performed and 5 thermocouples with markers were implanted epicardially at the PVs and superior vena cava (SVC). The tissue temperatures during hotballoon ablation (balloon temperature 70 or 73 degree, 180 sec per each) were recorded, and the maximum tissue temperature and distance from the balloon-tissue contact surface based on fluoroscopy were assessed.
Results: A total of 22 SVC and 19 PV targeted energy deliveries were performed. Representative PV tissue temperature rises during hotballoon ablation are shown in the left panel of the Figure and the distance vs. maximum tissue temperature in the right panel. The best cutoff value of the distance from the balloon surface achieving lethal temperatures >50 degree was 3.5 mm. Full-thickness circumferential PV lesions were observed with all hotballoon applications.
Conclusion: This study showed the actual tissue temperatures during hotballoon ablation and distance from the balloon surface to reach a maximum temperature. Effective tissue temperatures over 50 degrees were achieved within 3.5 mm of the balloon surface. This data helped to support the clinical efficacy and safety of hotballoon ablation.