Safety of an esophageal deviator for atrial fibrillation catheter ablation

Background

Esophageal thermal injury is a complication of atrial fibrillation (AF) ablation, and it can be avoided by esophageal deviation during left atrial posterior wall radiofrequency catheter ablation.

Objective

This study aimed to evaluate the safety of a nitinol-based mechanical esophageal displacement device (MEDD) and its performance.

Methods

This preclinical safety study was conducted on 20 pigs, with 10 undergoing radiofrequency AF ablation using the MEDD and 10 serving as a control group under anticoagulation but without radiofrequency application. Esophageal traumatic injuries were classified from 0 to 4 and were grouped as absent (grade 0), minor (grade 1 or 2), moderate (grade 3), or major risk lesions (grade 4) by anatomopathological study. Grades 1 and 2 were considered acceptable. Fluoroscopy was used to measure displacement.

Results

Five (25%) pigs developed traumatic lesions, 4 with grade 1 and 1 with grade 2 (2-mm superficial ulcer). There was no difference in lesion occurrence between the radiofrequency and control groups (30% and 20%, respectively; P = .43). Under rightward displacement, the right edge moved 23.9 (interquartile range [IQR] 21.3-26.3) mm and the left edge moved 16.3 (IQR 13.8-18.4) mm (P < .001) from baseline. Under leftward displacement, the right edge moved 13.5 (IQR 10.9-15.3) mm and the left edge moved 16.5 (IQR 12.3-18.5) mm (P = .07). A perforation to the pharyngeal diverticulum occurred in 1 pig, related to an accidental extubation.

Conclusion

In pigs, the MEDD demonstrated safety in relation to esophageal tissue, and successful deviation. Esophageal traumatic injuries were acceptable, but improper manipulation led to pharyngeal lesion.