The influence of varying energy settings on efficacy and safety of endoscopic pulmonary vein isolation.

Background: The optimal energy setting for endoscopic pulmonary vein (PV) isolation (PVI) has not yet been determined.

Objective: To assess the influence of varying energy settings on the efficacy and safety of endoscopic PVI.

Methods: In the current prospective study, 30 patients with paroxysmal atrial fibrillation were consented for PVI using the endoscopic ablation system. Ablation was performed by using 5.5 and 7.0 W (group A), 7.0 and 8.5 W (group B), and 8.5 and 10.0 W (group C) along the posterior and anterior portion of each PV, respectively. Intraluminal esophageal temperature was measured via a temperature probe with a cutoff of 38.5°C. Endoscopy was performed 2 days postablation.

Results: After the completion of the initial circular lesion set, acute PVI was achieved in 25 of the 36 (69%) PVs in group A, in 29 of the 40 (73%) PVs in group B, and in 36 of the 40 (90%) PVs in group C, respectively. The rate of acute PVI was significantly higher in group C than in group A (P = .025) and group B (P = .045); there was no difference when comparing group A and group B (P = .77). Esophageal thermal lesions were detected in 0 of the 10 patients in group A, in 1 of the 10 (10%) patients in group B, and in 1 of the 10 (10%) patients in group C. Mean procedure and fluoroscopy times were 219 ±42 and 30 ± 10, 239 ± 61 and 38 ± 14, and 207 ± 31 and 28 ± 8 minutes for group A, B, and C, respectively.

Conclusions: The use of higher energy settings increases the efficacy of acute endoscopic ablation system-based PVI without comprising safety. Further investigation is mandatory before final conclusions can be drawn.