New Parameter to Predict Recurrence of Paroxysmal Atrial Fibrillation after Pulmonary Vein Isolation by the P-Wave Signal-Averaged Electrocardiogram

Noninvasive methods for predicting the recurrence of atrial fibrillation (AF) after initial pulmonary vein isolation (PVI) have not been well described. The aim of the present study was to evaluate the usefulness of the P-wave signal-averaged electrocardiogram (P-SAECG) in predicting the recurrence of AF after initial PVI. The P-SAECG was recorded before and after (within 1 week) the initial PVI session. The filtered P-wave duration (FPD) and root mean square voltage of the last 20ms of the filtered P-wave (LP20) were measured in 87 consecutive idiopathic AF patients (ejection fraction ≥50%, B-type natriuretic peptide ≤200pg/ml). During the follow-up period (12±7 months), 22 of 87 (25%) patients had recurrence of AF (11 with paroxysmal AF and 11 with persistent AF). In the group with recurrence of paroxysmal AF, the post-PVI FPD was significantly shorter and the post-PVI LP20 was significantly larger than in the non-recurrence group. Furthermore, the post-PVI LP20/FPD ratio was significantly higher in the group with paroxysmal AF recurrence than in the non-recurrence group (0.024±0.009 vs 0.015±0.007µV/ms, respectively; P0.015µV/ms than in those with a post-PVI LP20/FPD ≤0.015µV/ms. The optimal post-PVI LP20/FPD cut-off value of 0.015µV/ms had a sensitivity of 90% and a specificity of 60%. The data also suggest that the post-PVI LP20/FPD may be a new parameter for predicting successful PVI in patients with idiopathic paroxysmal AF after PVI