Ablation outcome in patients with atrial fibrillation undergoing ICE-guided pulsed-field ablation

Abstract Background Prior experiences from preclinical studies indicate the critical need of catheter-tissue- contact for creation of consistent transmural lesions in pulsed-field ablation (PFA). Intracardiac echocardiography (ICE) not only provide real-time visualization of cardiac structures, but also ensure adequate contact with the tissue. Objective We evaluated ablation outcome and reconnection rate following ICE-guided PFA procedure in patients with atrial fibrillation (AF). Methods Consecutive patients receiving ICE-guided PFA procedure were included in this multi-center analysis. All patients received isolation of PVs (PVI). Additional ablation of left atrial posterior wall (LAPW) was decided based on operator’s discretion. Concentric overlapping lesions were placed in the LAPW. Number of applications were determined on a case-by-case basis. ICE and fluoroscopy were used to optimize contact between the PFA catheter and the targeted tissue. All procedures were performed under uninterrupted anticoagulation. Mapping was done before and after ablation to confirm electrical isolation. Arrhythmia-monitoring was done for 1-year with periodic clinic visits, event recorders and 7-day Holter monitoring. Results A total of 372 patients [age: 62.69 ± 10.41 years, male: 201 (71.3%), paroxysmal AF: 67 (18%)] were included in this analysis of which 48 (12.9%) underwent PVI-only and the remaining subjects received additional ablation of LAPW. Mean number of applications were 34.67 ± 8.88 and 73.65 ± 37.21 for PVI-only and PVI+LAPWI cohorts respectively (p<0.001). No major procedural complications such as esophageal injury, atrio-esophageal fistula, pericardial effusion requiring drainage or cerebrovascular accidents were reported. During 1-year follow-up, 38 (10.2%) patients underwent repeat procedure for recurrence. Reconnection of PV and LAPW were found in only 2 (5.2%) patients. In all 38 patients, new triggers initiating AF were detected to be originating from interatrial septum: 25 (65.8%), superior vena cava: 9 (23.7%), coronary sinus: 7 (18.4%) and left atrial appendage: 6 (15.8%). Conclusion ICE-guided PFA procedures are safe and produce durable lesions leading to very low reconnection rate. The recurrence was mostly due to new triggers initiating AF.