AbstractIntroductionCryoballoon ablation is a safe and efficient rhythm control strategy in atrial fibrillation (AF) patients. The impact of time from diagnosis to ablation is unclear. The aim of this study was to examine the impact of timing of first‐time cryoballoon ablation on AF recurrence in a nationwide cohort of AF patients.Methods and ResultsFrom nationwide registers, all AF patients ≥18 years of age who underwent first‐time AF cryoballoon ablation in Denmark from 2012 to 2018 were included. The AF patients were stratified by ablation timing: Early group (≤1 year after AF diagnosis), intermediate group (1–3 years after AF diagnosis), and late group (≥3 years after AF diagnosis). By adjusted Cox regression models, the effect of timing on AF recurrence was examined.This study included 1064 AF patients with a median age of 63 years. Most patients were male (66%) and had paroxysmal AF (67%). The 1‐year risk of AF recurrence increased from 31% in the early group to 41% and 44% in the intermediate and late group. The hazard ratios (95% confidence intervals) were 1.28 (0.95, 1.74) in the intermediate group and 1.42 (1.09, 1.86) in the late group when compared to the early group. Continuous diagnosis‐to‐ablation time seemed to have the greatest impact on AF recurrence within the first 2 years.ConclusionIn AF patients undergoing cryoballoon ablation, late timing of ablation was associated with a significantly higher AF recurrence rate when compared to early timing of ablation. These findings support early cryoballoon ablation to improve the outcomes after ablation.