Assessment of the transmurality of posterior left atrial pulsed field ablation lesions using transesophageal recordings and pacing

Pulsed field ablation (PFA) may be utilized to perform posterior left atrial (PLA) ablation in addition to pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). The purpose of this study was to determine the transmurality of PFA lesions in the PLA using transesophageal electrogram recording and pacing.

Retrospective analysis of patients with AF who underwent PFA of the PLA and transesophageal recording and/or pacing was conducted. In all patients, a baseline 3D electroanatomic map (EAM) of the left atrium was created. Then, a multi-electrode catheter was inserted into the esophagus for pre-ablation transesophageal pacing and recording. The esophageal catheter was removed during ablation. Following PFA, the esophageal catheter was reinserted to the same position for post-ablation transesophageal recording and pacing. Esophageal electrograms were displayed in all patients on the recording system. EAM of the esophagus were performed at the discretion of the operator. Pacing outputs and configurations were the same pre- and post- ablation.

There were 10 consecutive patients (70% male, age 68 ± 14y, 50% redo AF ablations) included in analysis (Table 1). Of these, EAMs of the esophagus were created in 3 patients. Esophageal electrograms were successfully eliminated following PLA in all patients (Table 1, Figure 1a-b). Left atrial capture was achievable with transesophageal pacing in 7 patients pre-ablation. Following ablation, left atrial capture was not achievable in any patients (Table 1, Figure c-f).

Pulsed field ablation lesions to the posterior left atrium are likely acutely transmural based on transesophageal recordings of atrial electrograms and success of left atrial capture via transesophageal pacing before versus after ablation.Figure 1  Table 1