Standalone PFA for Complex Macro-Reentrant and Fibrillatory Substrates following Mustard-Atrial Switch

The emergence of pulsed field ablation (PFA) has revolutionized atrial arrhythmia (AA) ablation practice, mainly in adults with normal structural hearts. Little is known about its applicability in adults with CHD. A 41-year-old male with d-transposition of the great arteries (d-TGA) status post Mustard procedure with longstanding, and multiple prior ablations presented with recurrent symptomatic AA refractory to medical therapy. Endocardial AA ablation was performed using a standalone PFA-based approach. Following comprehensive bilateral atrial mapping, a critical isthmus was identified on the prior incisional scar for interatrial baffle, consistent with incisional atrial flutter. Immediate termination was achieved following the first PFA delivery with pentaspline catheter (Farapulse, Boston Scientific). Additional scar homogenization was delineated entirely with only PFA. The patient has remained clinically free from AA over 4 months on follow-up. Our case underscores the novelty and applicability of a standalone PFA not only in patients with normal cardiac structure, but also in adults with CHD.