-Original-

Chronic Ablation Lesions after Cryoballoon and Hot Balloon Ablation of Atrial Fibrillation

Ryuta Watanabe, Yasuo Okumura, Koichi Nagashima, Yuji Wakamatsu, Akimasa Yamada and Sayaka Kurokawa

Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan

Background: Chronological changes in ablation lesions after cryoballoon ablation (CBA) and hot balloon ablation (HBA) of atrial fibrillation (AF) remain unclear.
Methods: Of 90 patients who underwent initial balloon-based catheter ablation of AF and cardiac magnetic resonance imaging (cMRI) 3 months after ablation, data from 48 propensity score-matched patients (24 per group; 34 males; age 62±10 years) were analyzed. High-density pulmonary vein-left antrum (PV-LA) voltage mapping was performed after PV isolation, and low voltage areas around the PV ostia were defined as the total acute ablation lesion area (cm²). cMRI-derived dense fibrotic tissue localized around PVs was defined as the total chronic ablation lesion area (cm²). The percentage of total ablation lesion areas to total PV-LA surface area (%ablation lesion) was calculated during each phase, and %acute ablation lesion and %chronic ablation lesion areas were compared in patients who had undergone CBA and HBA.
Results: The %acute ablation lesion area was larger for the CBA group than for the HBA group (30.8±5.8% vs. 23.0±5.5%, p < 0.001). There was no difference in %chronic cMRI-derived ablation lesion area (24.8±10.8% vs. 21.1±11.6%, p = 0.26) between groups. The rates of chronic AF recurrence were 12.5% and 8.3%, respectively (p = 0.45; log-rank test). LA volume and LA surface area were strongly associated with AF recurrence, but %chronic ablation lesion area was not (27±8% vs. 23±12%, p = 0.39).
Conclusion: Large acute ablation lesions after CBA were smaller during the chronic phase. The size of chronic ablation lesions and the rate of AF recurrence were both similar for CBA and HBA.

J Nippon Med Sch 2023; 90: 69-78

Keywords
atrial fibrillation, cyroballoon, hot balloon, magnetic resonance image

Correspondence to
Yasuo Okumura, MD, PhD, Division of Cardiology, Department of Medicine, Nihon University School of Medicine, 30-1 Ohyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan
okumura.yasuo@nihon-u.ac.jp

Received, July 8, 2022
Accepted, August 24, 2022