Backgrounds: Ablation index (AI) is useful to complete circumferential pulmonary vein isolation (CPVI) for atrial fibrillation (AF), but the role of radiofrequency power in AI-guided CPVI remains to be elucidated.
Methods: We investigated 60 patients with AF undergoing AI-guided CPVI (mean age, 66 ± 9 years; nonparoxysmal AF in 16). The first 40 patients were randomly assigned to low-power (LP; n = 20) and medium-power (MP; n = 20) groups and the following 20 patients to high-power (HP). In LP, radiofrequency (RF) application was done at 30 W at the anterior and 20 W at the posterior left atrial (LA) wall, while in MP, it was at 40 W at the anterior and 30 W at the posterior LA wall. In HP, 50 W was applied at the anterior, 40 W at posterior LA wall and 30 W on the esophagus. At each ablation point, target AI was 400 at the anterior, 360 at the posterior LA wall, and 260 on the esophagus.
Results: The time to complete both-side CPVI was shortest in HP (median, 40 minutes, interquartile range [IQR], 28-63) followed by MP (58 [49-83] minutes, P = .008 vs HP) and LP (84 [72-93] minutes, P = .002 vs MP). Higher RF power application significantly increased first-pass isolation rate (55% in LP, 80% in MP and 85% in HP, P = .002) and decreased LA-PV reconnection rate (10% in LP, 8% in MP, and 0% in HP, P = .03).
Conclusion: In AI-guided PVI, the HP RF application can shorten the time to complete PVI with a high rate of first-pass isolation and a low rate of LA-PV reconnection.
Keywords: ablation index; atrial fibrillation; catheter ablation; high-power radiofrequency application; pulmonary vein isolation.
© 2019 Wiley Periodicals, Inc.