Lesion formation following pulsed field ablation for pulmonary vein and posterior wall isolation

Abstract Background Pulsed field ablation (PFA) results in unique lesion formation, but there is lack of in–vivo validation in terms of scar formation following atrial fibrillation (AF) ablation. Objective We aimed to access atrial lesion formation based on late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) following PFA for pulmonary vein (PV) and posterior wall isolation (PWI). Methods AF ablation was performed in 10 patients using a 31 mm pentaspline PFA catheter. After pulmonary vein isolation (PVI; n = 8 PFA‐applications/ PV; n = 4 in basket and n = 4 in flower configuration), another eight applications in flower configuration were conducted for concomitant PWI. Patients underwent LGE CMR 3 months after ablation aiming for quantification of left atrial (LA) scar. Results Acute procedural success was achieved in all patients. Mean procedure duration was 62 ± 7 min. and mean LA dwell time of the PFA catheter was 13 ± 2 min. Mean post ablation total LA scar burden was 8.1 ± 2.1% and mean scar width was 12.8 ± 2.1 mm. At the posterior LA, 22.6 ± 2.2% of the anatomical segment resulted in chronic scar tissue, concentrated at the PW. Postablation CMR found no evidence for PV stenosis or collateral damage of adjacent structures. At 7 months of follow‐up, 9/10 patients (90%) were free from arrhythmia recurrence. Conclusion PFA for AF resulted in durable and transmural atrial scar tissue at the PVs and PW. LGE CMR found a very homogeneous and contiguous lesion pattern with no signs for collateral damage.