Analysis for the primary predictive factor for the incidence of esophageal injury after ablation of atrial fibrillation.

Background: Esophageal injury (EI) is a serious complication that occurs after catheter ablation of atrial fibrillation (AF), however predictable factor of EI is unclear.

Methods: Among 308 patients who underwent AF ablation, upper gastrointestinal tract endoscopy was performed the next day after ablation to examine for EI. To define the primary factor that predicts EI, patients' characteristics, number and amount of radiofrequency energy applied to the posterior wall, ablation procedure, and the shortest distance between esophagus and posterior left atrium measured on contrast computed tomography (SD-CT) were analyzed.

Results: EI was found in 27 patients (8.8%). There were no significant differences in the patient characteristics, number and amount of radiofrequency energy applied to posterior wall or ablation procedure between patients with (Injury Group) and without EI (Non-Injury Group). However, SD-CT in the Injury Group was significantly shorter than that in Non-Injury Group (2.3±0.6mm vs 4.1±0.9mm, p<0.001). The area under a receiver operating characteristic curve using SD-CT as a predictive marker in EI patients was 0.988 (p<0.001). When the cut-off value of SD-CT was set at 2.9mm, the sensitivity and specificity for EI diagnosis were 92.3% and 96.8%, and the positive predictive value and negative predictive value were 0.75 and 0.99, respectively.

Conclusions: EI observed after catheter ablation of AF was closely associated with the SD-CT. Patients with SD-CT below 2.9mm have a potential risk of EI and thus must be strictly followed.