Difference in tissue temperature change between two cryoballoons

Open Heart. 2023 Dec 7;10(2):e002426. doi: 10.1136/openhrt-2023-002426.

Abstract

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.

Keywords: atrial fibrillation; catheter ablation; simulation training.

MeSH terms

  • Animals
  • Atrial Fibrillation* / diagnosis
  • Atrial Fibrillation* / surgery
  • Catheter Ablation*
  • Cryosurgery* / adverse effects
  • Equipment Design
  • Humans
  • Swine
  • Temperature