Impact of diagnosis-to-ablation time on rhythm outcome after catheter ablation for paroxysmal versus non-paroxysmal atrial fibrillation

Background and aims: The difference of the impact of the diagnosis-to-ablation time (DAT) on rhythm outcome after catheter ablation (CA) between paroxysmal and non-paroxysmal atrial fibrillation (AF) remains undetermined. This study was designed to clarify the impact of DAT on outcome after the initial CA among AF types. Methods: We enrolled 619 patients (age 63 ± 11 years; 72 % male; 34 % non-paroxysmal AF) who underwent initial CA at our institute (Jan 2018–Dec 2022). The relationship between the DAT and recurrence after CA among AF types was investigated. Results: During the median 1038-day follow-up, 165 patients had AF recurrence. They had a higher percentage of non-paroxysmal AF (49.1 % vs. 29.4 %; p < 0.001), larger left atrium-diameter (mean 42 vs. 40 mm; p = 0.002) and longer DAT (median 1.7 vs. 0.8 years; p < 0.001) than those without recurrence. In COXproportional hazard analysis adjusted by confounders, the group with DAT ≥ 1 year, the optimal cutoff defined using receiver-operating characteristic curve analysis for recurrence, independently had a 2.3-fold greater risk of recurrence compared to the group without (p < 0.001). In a separate analysis with adjustment by confounders, paroxysmal and non-paroxysmal AF patients with DAT ≥ 1 year had 1.8-fold greater risk (p = 0.010) and 3.0-fold greater risk (p < 0.001), respectively, compared to those without. With respect to DAT-tertiles, paroxysmal AF patients in the top DAT-tertile (median 4.0 years) had 2.0-fold greater recurrence risk (p = 0.016), and non-paroxysmal AF patients in the top DAT-tertile had 4.0-fold greater recurrence risk, than those in the lowest DAT-tertile (p = 0.001). Conclusion: AF patients with a longer DAT had a worse rhythm outcome after CA irrespective of AF type.