Successful treatment of atrial flutter post-radiofrequency ablation for atrial fibrillation following atrial septal defect occlusion: a case report of pulsed field ablation.

Background: Atrial flutter (AFL) is a common arrhythmia following radiofrequency ablation (RFA) for atrial fibrillation (AF), with varying incidence depending on the ablation strategy. Patients with prior atrial septal defect (ASD) occlusion pose challenges for ablation, particularly when the lesions are located near the occluder. Pulsed field ablation (PFA) has emerged as a promising alternative to RFA for the treatment of AF or AFL; however, its use in patients with ASD occlusion remains unexplored. Case summary: We present the case of a 46-year-old female with a history of ASD occlusion and subsequent RFA for AF. Despite the initial success, she developed symptomatic AFL 3 months post-procedure. Intracardiac echocardiography (ICE)-guided transseptal puncture guided by ICE revealed an AFL originating from the slow conduction area around the ASD occluder. Pulsed field ablation was successfully performed, and AFL was terminated without complications. Post-procedural follow-up demonstrated maintenance of sinus rhythm. Discussion: Patients with ASD occlusion present unique challenges for ablation, including difficulties in transseptal puncture and risk of injury to the occluder. Pulsed field ablation offers a potential solution, with studies showing fewer reconnected pulmonary veins and larger lesion creation compared with traditional methods. In our case, PFA effectively terminated the refractory AFL, highlighting its utility in this patient population. Moreover, the use of the Jinjiang PFA catheter with pulse circuit self-checking technology ensured procedural safety, particularly near the occluder.