Efficacy of atrial substrate modification based on dominant frequency of paroxysmal atrial fibrillation

Background The endpoint of ablation procedures is suggested to be non‐inducibility of paroxysmal atrial fibrillation (PAF). However, the prognosis of induced AF/atrial tachycardia (AT) after pulmonary vein isolation (PVI) in PAF patients remains unclear. Methods A total of 122 PAF patients were divided into the following 3 groups: Group 1, 79 without AF/AT induced after PVI; Group 2, 21 with AF/AT induced or sustained after PVI, and followed by a high‐dominant frequency (DF) and continuous complex fractionated atrial electrogram (CFAE) site ablation and, if necessary, linear ablation; and Group 3, 22 with external cardioversion of AF/AT induced or sustained after PVI. High‐DF (DF≥8 Hz) and continuous CFAE (fractionated intervals≤50 ms) sites were targeted. The ablation endpoint was non‐inducibility of PAF. Results In Group 2, AF terminated in 2 patients with a high‐DF and continuous CFAE site ablation. In 4 patients, AF induced after cardioversion did not terminate with left atrium linear ablation, and required additional cardioversion. Common atrial flutter in 2 patients terminated with cavotricuspid isthmus ablation. An AT terminated with a roofline ablation. Finally, no AF/AT could be induced in any of the patients in Group 2 after all the procedures. The cumulative freedom from AF/AT recurrence without antiarrhythmic drugs in Groups 1 and 2 was significantly greater than that in Group 3 after 1 procedure during 12 months of follow‐up (90% and 91% vs. 64%, Log‐rank test P =0.001 and P =0.033, respectively). Conclusions Atrial substrate ablation may improve the clinical outcome after ablation in patients after PVI with residual arrhythmia inducibility.