Impact of pulmonary vein isolation on atrial late potentials: association with the recurrence of atrial fibrillation

In patients with paroxysmal atrial fibrillation (AF), the P-wave signal-averaged electrocardiogram often demonstrates a low-amplitude potential at the terminal part of filtered P-wave (atrial late potential: A(LP)), which would originate from delayed pulmonary vein (PV) potentials. The aim of this study was to investigate the impact of PV isolation on P-wave morphology, and explore the association between A(LP) and AF recurrence after ablation. We enrolled 88 consecutive paroxysmal AF patients scheduled for ablation. The signal-averaged electrocardiogram was obtained at baseline and 1 day after ablation. An A(LP) was defined as a P-wave duration of 130 ms and a root-mean-squared voltage of the terminal 20 ms of 2.0 V. A pre-procedural A(LP) was found in 37 (42) patients and a post-procedural A(LP) was found in 26 (30) patients. We completed PV isolation in all patients and followed them for 16 4 months. The AF recurrence rate was 30 (26 patients) and was similar between patients with and without pre-procedural A(LP) (27 vs. 31, respectively, P 0.66); however, AF recurrence was significantly higher in patients with than without post-procedural A(LP) (54 vs. 19, respectively, P 0.001). In multivariate logistic regression analysis, post-procedural A(LP) was independently associated with AF recurrence (odds ratio 4.22, 95 confidence interval 1.52u11.7). Pulmonary vein isolation can modify A(LP) in a substantial number of patients with paroxysmal AF. Post-procedural A(LP) is associated with increased risk of future AF recurrence.