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 degrees 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.