Abstract 14252: Redefining the Blanking Period After Cryoballoon Ablation for Atrial Fibrillation: From Korean Cryoballoon Ablation Registry

Abstract

Background: Early recurrence (ER) of atrial arrhythmia in blanking period (<3 months) after radiofrequency ablation for atrial fibrillation (AF) has been considered as benign episode. Recently, there were controversies of long-term outcome of ER in radiofrequency ablation. the evidences of long-term impact of ER in cryoballoon ablation was still lacking. Hypothesis: There would be a significant impact of ER in patients with cryoballoon ablation on late recurrence of atrial tachyarrhythmia. Thus, this study sought to evaluate long-term outcome according to presence and timing (<1 month, 1-2 months, 2-3 months) of ER after cryoballoon ablation. Methods: Using the data from a multicenter registry of cryoballoon ablation for AF in Korea between May 01, 2018, and June 30, 2022, we identified 2,654 eligible patients. The primary outcome was late recurrence of atrial tachyarrhythmia including atrial fibrillation, atrial flutter, or atrial tachycardia longer than 30 seconds, excluding a blanking period of 3 months. A multivariable Cox proportional hazard model was performed to evaluate the impact of ER for late recurrence of AF. Results: Among 2,654 patients, 763 (28.7%) patients experienced ER of atrial arrhythmia after cryoballoon ablation. During mean follow-up periods (21.2 ± 10.3 months) after 3-month blanking period, 874 (32.9%) patients developed late recurrence of atrial arrhythmia. The 1-year freedom from late recurrence were 85.5% in patients without ER, 44.1% in those with ER <1 month, 32.4% in those with ER of 2-3 month, and 39.0% in those of ER with 2-3 month, respectively ( p = 0.0001). In multivariable Cox proportional hazard model, ER was significantly associated with late recurrence (hazard ratio: 3.98; 95% confidence intervals: 3.47-4.57) ( p = 0.001). Conclusion: Anytime ER after cryoballoon ablation is a significant predictor of late recurrence of atrial arrhythmia.