Background:

During left atrial (LA) ablation, thermal ablation modalities can cause esophageal damage, such as atrio-esophageal fistula. Pulsed field ablation (PFA) for paroxysmal atrial fibrillation (PAF) is a new, commercially available, non-thermal ablation modality. Pre-clinical evaluation of PFA showed absence of thermal injury to the esophagus due to the tissue specificity of PFA. Only limited data from very small clinical studies on absence of esophageal injury after PFA is available. We investigated real-world data on possible esophageal injury after clinical routine PFA for PAF.

Methods:

LA appendage thrombus was excluded by cardiac computed tomographic angiography, no pre- or intraprocedural transesophageal echocardiography was performed. PFA was carried out according to standard protocol, with a minimum of 8 applications per pulmonary vein. Patients underwent only pulmonary vein (PV) isolation without intended additional lesions. Pre- and post-ablation, a high-density, bipolar voltage, 3D map (Biosense Webster) of the LA was obtained. Post-ablation, patients were not treated with proton-pump inhibitors. One day after PVI, a diagnostic esophagoscopy (EG) was performed by an experienced gastroenterologist, no biopsies were taken. All patients were scheduled for a 30-day clinical follow-up in the outpatient department.

Results:

In 30 patients (age 63±10 years; 47% male; CHA₂DS₂-VASc-Score 2 [IQR 1-3]), PFA was performed, with all PVs acutely isolated. Post-ablation, all voltage maps consistently showed extensive antral PV lesions. The clinical course was uneventful in all patients, none of the patients reported chest discomfort. All patients underwent uncomplicated EG, there were no visible lesions or ulcers. At 30-day follow-up, no patient reported chest discomfort, there were no procedure-related complications.

Conclusion:

In a real-world, non-clinical study setting, PFA seems to be a safe modality for LA catheter ablation near the esophagus.

Figure:

Postero-anterior view of the LA before (left) and after (right) ablation with the course of the esophagus (dark grey) projected over the posterior LA wall. The colours of the high-density, bipolar voltage, 3D map post-ablation (right) show the extensive antral ablation lesions (<0.5 mV) visualized as areas of non-magenta colours.