Abstract 2549: Unexpected High Incidence of Esophageal Injury After Pulmonary Vein Isolation Using Mechanical Navigation
Background: Mechanical navigation (MN) is a novel technology for pulmonary vein isolation (PVI) treating atrial fibrillation (AF). However, the incidence of thermal esophageal injury using standard power settings is unknown.
Methods and Results: Thirty-nine patients (pts, 23 male; 60±11 years, LA 44±6mm, hypertension n=27) without history of peptic disease underwent circumferential PVI for AF. Ablation was performed using MN in 14 pts or manually in 25 pts with a 3.5 mm irrigated tip catheter. Standard ablation power settings (30W, 17 ml/min flow, maximal temperature 43°C) were used during ablation along the LA posterior in the manual (n=25) and the MN1 group (n=4). In these 2 groups, the operator was blinded to the esophageal temperature (Teso). In the MN2 group ablation power along the posterior LA wall was reduced to 20W and energy delivery was terminated if Teso increased to >41°C. Endoscopy was performed at day 2 after PVI. Esophageal lesions were classified as no lesion, minimal thermal lesion (erythema with intact mucosa) and ulceration (hole in the lining of the esophagus). PVI was achieved in all pts. In the manual group no esophageal lesions, minimal lesions and ulcerations were found in 16 (64%), 6 (24%) and 3 (12%) pts, respectively. All 4 pts (100%) in the MN1 group had an ulceration and one pt developed esopageal perforation requiring covered stent placement at day 14 that was removed at day 81 after PVI. In the MN2 group, no lesion (9 pts, 90%) or a minimal lesion was found (1 pt, 10%).
Conclusion: A high incidence of thermal injury to the esophagus including an esophageal perforation was noted following irrigated RFC based PVI using MN with standard power settings. Reduction of ablation power to 20 W along the posterior LA wall and termination of energy delivery if Teso >41°C appears to be safe.