Maximum P-wave duration and P-wave dispersion predict recurrence of paroxysmal atrial fibrillation in patients with Wolff-Parkinson-White syndrome after successful radiofrequency catheter ablation

Background: Identification of patients at risk for PAF recurrence after AP ablation is important because of the necessity for additional therapies. Objectives: To determine whether Maximum P-wave duration (P-max) and P-wave dispersion (P-d) detected on surface ECG after successful accessory pathway ( AP) ablation can predict the recurrence of paroxysmal atrial fibrillation ( PAF). Methods: Seventy-eight patients with Wolff-Parkinson-White (WPW) syndrome who had at least one documented PAF episode and underwent catheter ablation were enrolled. P-max, minimum P-wave duration (P-min) and P-d were determined on a surface ECG recorded on a high resolution computer screen on day 2 after ablation of the AP. Results: There was no significant difference in terms of basic clinical data and electrophysiological findings between patients with (Group-1, n = 19) and without (Group-2, n = 59) recurrence of PAF during follow-up of 21 +/- 10 months. P-max and P-d were significantly higher in Group-1 than Group-2 (120 +/- 15 vs. 96 +/- 10 ms and 47 +/- 12 vs. 25 +/- 7 ms, respectively; p < 0.001 for both). P-min didn't differ significantly. A P(max)value of >= 103 ms separated Group-1 from Group-2 with a sensitivity of 84.2%, specificity of 72.9%, positive predictive value of 50%, and negative predictive value of 93.5%. A P-d value of >= 32.5 ms separated Group-1 from Group-2 with a sensitivity of 89.5%, specificity of 84.7%, positive predictive value of 65.4%, and negative predictive value of 96.2%. P-max (p < 0.010) and P-d (p < 0.001) were found to be significant univariate predictors of PAF, whereas only P-d remained significant in multivariate analysis (p = 0.037). Conclusion: P-d >= 32.5 ms and P-max >= 103.0 ms predict the recurrence of PAF after ablation with acceptable positive and negative predictive values. P-d >= 32.5 ms is an independent predictor of recurrence of PAF after catheter ablation in patients with WPW syndrome.