The use of an esophageal catheter to check the results of left atrial posterior wall isolation in the treatment of atrial fibrillation

BACKGROUND: Left atrial posterior wall isolation (LAPWI) via catheter, surgical, and hybrid techniques is a promising treatment for persistent atrial fibrillation (PersAF). We investigated whether confirmation of LAPWI can be achieved using an esophageal pacing and recording electrode. METHODS: Patients undergoing PersAF ablation with the intention to achieve LAPWI were enrolled. Two approaches to LAPWI were tested: (1) ablation using endocardial catheter ablation only, and (2) "Staged Hybrid" ablation with thoracoscopic epicardial ablation, followed by endocardial left atrial electrophysiological study and catheter ablation where necessary. Patients enrolled in the study all required further catheter ablation to achieve LAPWI in this group. In both the groups, esophageal recording and esophageal pacing was performed at the start of mapping and electrophysiological study and compared with endocardial electrophysiological findings. This was repeated at the end of the procedure. RESULTS: Twenty patients (16 M, four F) were studied. Endocardial electrophysiological study showed that in none of the cases was the posterior left atrial wall electrically isolated at the start of the study. One patient with Barrett's esophagus failed to sense or pace from the esophagus at any point in the study. In the remaining 19/19, esophageal pacing captured the atrial rhythm at the start of the procedure. LAPWI was then achieved in 17/19 using endocardial catheter ablation; retesting at this point showed sensing and capture of the atrium from the esophagus was abolished. In the remainder sensing and capture persisted. CONCLUSIONS: Esophageal pacing can be used to confirm or refute electrical isolation of the left atrial posterior wall.