Left atrial posterior wall isolation using pulsed-field ablation: procedural characteristics, safety, myocardial injury and short-term outcomes

Abstract

Abstract Background Pulsed-field ablation (PFA) has emerged as a novel treatment strategy for patients with atrial fibrillation (AF). Among targets beyond pulmonary vein isolation (PVI), ablation of the left atrial posterior wall (LAPW) has gained increased interest in patients with persistent AF. PFA offers a novel ablation technology possibly able to overcome the obstacles of incomplete isolation and concerns of damage to adjacent structures. Purpose To assess procedural characteristics, safety, myocardial injury and short-term outcomes of patients undergoing LAPW ablation in a clinical setting. Methods Consecutive patients undergoing PFA PVI with LAPW isolation were included. Using a multi-spline PFA catheter in a flower configuration, two anchor lesions per vein extending to the LAPW were deployed. Then, the wire was pulled back into the lumen, the PFA catheter and sheath were rotated along the entire LAPW in a flower configuration thereby creating overlapping lesions as assessed by a 3D-electro-anatomical mapping system. First-pass isolation was controlled using a multipolar mapping catheter. Complications were checked with an echocardiogram, high sensitivity cardiac troponin T was measured the next day and for recurrence detection a Holter ECG was performed during follow up. Results 25 patients with persistent AF undergoing PVI were included (age 69 ± 12 years, left atrial volume index 37 ml/m2). 17 patients underwent redo-PVI with LAPW and 8 patients first time PVI with LAPW ablation. The median number of applications to perform LAPW isolation using PFA was 24 (IQR 14-28). The median procedure time was 69 min (IQR 56-81). The median LA dwell time was 59 min (IQR 49-72). The median fluoroscopy time was 10 min (IQR 8-14). First-pass isolation was achieved in 24/25 cases (95%). There were no complications. High sensitivity cardiac troponin T level post-procedurally was 951 ng/L (IQR 717-1189). Median duration of follow-up were 95 days, (IQR 84-184), AF recurrence was observed in 2 patients (8%). Conclusion LAPW ablation with PFA appears safe and results in high acute isolation rates. The optimal technique to perform LAPW ablation using PFA needs to be defined. Data on long-term outcomes are missing.