Abstract 4140466: Time Interval from Right Atrium to Coronary Sinus Predicts Atrial Fibrillation Recurrence After Catheter Ablation

Background: Atrial fibrillation (AF) recurrence after catheter ablation may occur in patients with atrial remodeling progression. Atrial conduction time has been proposed as a marker of atrial remodeling. This study aimed to investigate whether atrial conduction time, measured during an electrophysiological study, is related to AF recurrence. Methods: Overall, 441 patients with AF (mean age, 67 years; female, 144 years; paroxysmal AF (PAF)/non-PAF, 233/208) who underwent initial radiofrequency catheter ablation at Mie University Hospital between January 2018 and December 2022 were enrolled. We measured the interval from the earliest potential in the right atrium (RA) to the latest potential in the coronary sinus (CS) (RA-CS interval time) using a BeeAT catheter during sinus rhythm after ablation (Figure 1). The primary endpoint was the recurrence of AF or other atrial tachycardia lasting > 30 s from 3 months to 1 year postoperatively. Results: During the 1-year follow-up, AF recurrence was observed in 44 patients. Patients were categorized into two groups according to AF recurrence. RA-CS interval times were significantly prolonged in the recurrence group (122.5±17.7 vs. 98.5±17.7 ms, p<0.001). In Cox regression analysis, after adjustment for confounders, RA-CS interval time was an independent factor associated with AF recurrence (Hazard ratio 1.05; 95% CI 1.03–1.07, p<0.001). The cut-off value of the RA-CS interval time using the ROC curve was 111 ms (Figure 2, AUC 0.845, 95% CI 0.785–0.905). Patients with RA-CS interval time ≥111 msec had a significantly higher recurrence rate rather than <111 ms (Figure 3). Conclusions: The RA-CS interval was an independent predictor of AF recurrence in the first year after catheter ablation.