Difference in tissue temperature change between two cryoballoons

• Published in: Open Heart
• Main Authors: Hayashi, Takahiro, Hamada, Kohei, Iwasaki, Kiyotaka, Takada, Jumpei, Murakami, Masato, Saito, Shigeru
• Format: Text
• Language: English
• Published: BMJ Publishing Group 2023
• Subjects: Arrhythmias and Sudden Death; Arctic
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10711899/; http://www.ncbi.nlm.nih.gov/pubmed/38065585; https://doi.org/10.1136/openhrt-2023-002426

BACKGROUND: Cryoballoon ablation, especially Arctic Front Advance Pro (AFA-Pro) (Medtronic, Minneapolis, Minnesota, USA), has been widely recognised as a standard approach to atrial fibrillation (AF). Recently, Boston Scientific has released a novel cryoballoon system (POLARx). Despite comparable acute clinical outcomes of these two cryoballoons, the recent study reported a higher complication rate, especially for phrenic nerve palsy, with POLARx. However, their impact on biological tissue remains unclear. OBJECTIVE: The purpose of our study is to evaluate temperature change of biological tissue during cryoablation of each cryoballoon using a porcine experimental model. METHOD: A tissue-based pulmonary vein model was constructed from porcine myocardial tissue and placed on a stage designed to simulate pulmonary vein anatomy and venous flow. Controlled cryoablations of AFA-Pro and POLARx were performed in this model to evaluate the tissue temperature. A temperature sensor was set behind the muscle and cryoballoon ablation was performed after confirming the occlusion of pulmonary vein with cryoballoon. RESULTS: The mean tissue nadir temperature during cryoablation with AFA-Pro was −41.5°C±4.9°C, while the mean tissue nadir temperature during cryoablation with POLARx was −58.4°C±5.9°C (p<0.001). The mean balloon nadir temperature during cryoablation with AFA-Pro was −54.6°C±2.6°C and the mean balloon nadir temperature during cryoablation with POLARx was −64.7°C±3.8°C (p<0.001). CONCLUSION: POLARx could freeze the biological tissue more strongly than AFA-Pro.