Real-World Safety Profile of Atrial Fibrillation Ablation Using a Second-Generation Cryoballoon in Japan: Insight From a Large Multicenter Observational Study.

Objectives: This study sought to investigate the incidence and characteristics of the real-world safety profile of second-generation cryoballoon ablation (2nd-CBA) in Japan.
Background: Pulmonary vein isolation using second-generation cryoballoons is an accepted atrial fibrillation ablation strategy.
Methods: This multicenter observational study included 4,173 patients with atrial fibrillation (3,807 paroxysmal) who underwent a 2nd-CBA in 18 participating centers. The baseline data and details of all procedure-related complications within 3 months post-procedure in consecutive patients from the first case at each center were retrospectively collected.
Results: Adjunctive ablation after the pulmonary vein isolation was performed in 2,745 (65.8%) patients. Complications associated with the entire procedure were observed in 206 (4.9%) total patients, and in the multivariate analysis, the age (odds ratio: 1.015; 95% confidence interval: 1.001 to 1.030; p = 0.035) and study period were predictors. Air embolisms manifesting as ST-segment elevation and cardiac tamponade requiring drainage occurred in 63 (1.5%) and 15 (0.36%) patients, respectively. Six (0.14%) patients had strokes/transient ischemic attacks, among whom 5 underwent ablation under an interrupted anticoagulation regimen. No atrioesophageal fistulae occurred; however, 10 (0.24%) patients had symptomatic gastric hypomotility. Esophageal temperature monitoring did not reduce the incidence, and the incidence was significantly higher in patients with adjunctive posterior wall isolations or mitral isthmus ablation than those without (p = 0.004). Phrenic nerve injury occurred during the 2nd-CBA in 58 (1.4%) patients; however, all were asymptomatic and recovered within 13 months. One patient died of aspiration pneumonia.
Conclusions: This study had a high safety profile of 2nd-CBA despite including the early experience and high rate of adjunctive ablation. Care should be taken for air embolisms during 2nd-CBA.
Competing Interests: Funding Support and Author Disclosures This work was supported in part by grants (19K08487, 19K08576) for Cardiovascular Diseases from the Ministry of Health, Labour, and Welfare, Japan (to Drs. Miyazaki and Tada). Dr. Miyazaki has received consulting fees and speaker honoraria from Medtronic; and belongs to the endowed departments of Medtronic, Boston, Abbott, and Japan Lifeline. Dr. Kobori has received speaker honoraria from Medtronic. Dr. Kusano has received speaker honoraria from Daiichi-Sankyo Company, Ltd., Japan, Bristol Myers Squibb, Biotronik Japan, and Medtronic Japan; and has received research grants from Medtronic Japan and EP-CRSU Co., Ltd. Dr. Tada has received speaker honoraria from Daiichi-Sankyo Company, Ltd., Japan, Bristol Myers Squibb, Biotronik Japan, Boehringer Ingelheim Japan, and Johnson & Johnson; and has received research grants from Boehringer Ingelheim Japan, Bayer Yakuhin, Ltd., Japan, and Takeda Pharmaceutical Company, Ltd., Japan. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
(Copyright © 2021 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)