Advanced interatrial block predicts recurrence of atrial fibrillation after accessory pathway ablation in patients with Wolff‐Parkinson‐White syndrome

BACKGROUND: Paroxysmal atrial fibrillation (AF) frequently occurs in patients with Wolff‐Parkinson‐White (WPW) syndrome. Although successful ablation of the accessory pathway (AP) eliminates paroxysmal AF in some patients, in other patients it can recur. HYPOTHESIS: We investigated the clinical utility of advanced interatrial block (IAB) for predicting the risk of AF recurrence in patients with verified paroxysmal AF and WPW syndrome after successful AP ablation. METHODS: This retrospective study included 103 patients (70 men, 33 women; mean age, 44 ± 16 years) with WPW syndrome who had paroxysmal AF. A resting 12‐lead electrocardiogram was performed immediately after successful AP ablation to evaluate the presence of advanced IAB, which was defined as a P‐wave duration of >120 ms and biphasic [±] morphology in the inferior leads. RESULTS: During the mean follow‐up period of 30.9 ± 20.0 months (range, 2‐71 months), 16 patients (15.5%) developed AF recurrence. Patients with advanced IAB had significantly reduced event‐free survival from AF (P < .001). Cox regression analysis with adjustment for the left atrial diameter and CHA(2)DS(2)‐VASc score identified advanced IAB (hazard ratio, 9.18; 95% confidence interval [CI], 2.30‐36.72; P = .002) and age > 50 years (hazard ratio, 12.64; 95% CI, 1.33‐119.75; P = .027) as independent predictors of AF recurrence. CONCLUSIONS: Advanced IAB was an independent predictor of AF recurrence after successful AP ablation in patients with WPW syndrome.