Endoscopic evaluation of the esophagus after catheter ablation of atrial fibrillation using contiguous and optimized radiofrequency applications

Background: The incidence of endoscopically detected esophageal lesions after pulmonary vein isolation (PVI) is as high as 18%. Intraesophageal temperature rise (ITR) during ablation is a predictor of esophageal injury.

Objective: The purpose of this study was to describe an ablation strategy aiming to enclose the pulmonary veins with contiguous, stable, and optimized radiofrequency applications (referred to as CLOSE-PVI). We evaluated esophageal and periesophageal injury with endoscopy in patients revealing ITR during CLOSE-PVI.

Methods: Eighty-five patients with ITR during CLOSE-PVI underwent endoscopy of the esophagus (with ultrasound in 38 patients). PVI consisted of contact force (CF)-guided encircling of the veins using 35-W applications, respecting strict criteria of intertag distance (≤6 mm) and ablation index (AI; 550 arbitrary unit [au] anterior wall, 400 au posterior wall, 300 au if ITR >38.5°C).

Results: Endoscopy was performed 9 ± 4 days after PVI. At the posterior wall, median power was 35 W [interquartile range (IQR) 35-35], application time 18 ± 5 seconds, CF 13 ± 6g, and AI 403 ± 38 au. A median of 5 applications [IQR 4-7] per patient over a length of 21.8 ± 6.8 mm resulted in ITR >38.5°C (median 39.9°C, IQR 39.2°C-41.2°C, range 38.6°C-50.0°C). For these applications, median power was 35 W [IQR 30-35], application time 14 ± 3 seconds, CF 12 ± 5g, and AI 351 ± 38 au. The incidence of esophageal erythema/erosion on endoscopy was 1 of 85 (1.2%) and of ulceration was 0 of 85 (0%). The incidence of mediastinal or esophageal injury on ultrasound was 0 of 38 (0%).

Conclusion: The occurrence of esophageal or periesophageal injury after CLOSE-PVI is markedly low (1.2%). Absence of esophageal ulceration in patients with ITR suggests that this strategy of delivering contiguous, relatively high-power, and short-duration radiofrequency applications at the posterior wall is safe.