Early identification and treatment of PV re-connections: role of observation time and impact on clinical results of atrial fibrillation ablation

AIMS: Circumferential pulmonary vein isolation (CPVI) has been reported to account for 30% of atrial fibrillation (AF) recurrence after initial ablation, and pulmonary vein (PV) re-connection accounts for about 80% of AF recurrence. There is no information in the literature whether early identification and treatment of acute PV conduction recovery during initial ablation has an impact on subsequent clinical results. The objective is to investigate the prevalence of acute PV conduction recovery during the observation time after PV isolation for paroxysmal AF, and to evaluate the impact of re-isolation treatment on clinical results. METHODS AND RESULTS: Ninety cases with paroxysmal AF (51 males, mean age of 56.4 +/- 12.3 years) were randomized to 3 groups to undergo CPVI. In Group A, there was no observation time post-ablation. In Group B, there was 30 min of observation time post-ablation. In Group C, there was 60 min of observation time post-ablation. All PV re-conduction was re-isolated at the end of the observation time. ECG and Holter monitors were used to evaluate the clinical effectiveness of ablation. All cases underwent the procedure successfully. The mean procedural time in Group A was significantly shorter than in Group B and Group C, but there was no significant difference on fluoroscopic time and PV isolation time among the three groups. In Group B, PV re-conduction occurred in 8 cases (25%) at 30 min post-isolation, in 10 cases (31.2%) at 60 min post-isolation for left PVs, and in 6 cases (18.8%) at 30 min post-isolation for right PVs. In Group C, PV re-conduction for left PVs occurred in 9 cases (30%) at 30 min post-isolation and in 11 cases (36.7%) at 60 min post-isolation; for right PVs this occurred in 7 cases (23.3%) at 30 min post-isolation and in 8 cases (26.7%) at 60 min post-isolation. During a mean follow-up of 6.7 +/- 2.3 months, 17 cases (60.7%) in Group A, 27 cases (84.3%) in Group B, and 26 cases (86.7%) in Group C had no recurrence of atrial tachyarrhythmias, P = 0.04. CONCLUSION: The prevalence of acute PV conduction recovery was about 30% after PV isolation, which mostly occurred within 30 min after initial isolation. Re-isolation of recovered PV conduction contributed to the improvement in the success rate of ablation for paroxysmal AF.