High-density mapping-guided regional pulsed field ablation for atrial appendage tachycardia: a two-case report

Background Focal atrial tachycardia (AT) arising from an atrial appendage is uncommon and technically challenging because the thin, trabeculated anatomy may impair catheter stability and tissue apposition. Experience with pulsed field ablation (PFA) for this indication remains limited. Case presentation: A 42-year-old man with recurrent right atrial appendage AT and a 38-year-old woman with left atrial appendage AT underwent high-density activation mapping. In both patients, a discrete region of earliest activation with centrifugal spread was identified. A mapping-guided regional lesion strategy was implemented using a VARIPULSE variable-loop circular catheter, with PFA delivered across the mapped region and selected appendage segments. In the first patient, AT terminated during PFA at the mapped distal RAA target and was subsequently non-inducible. In the second, a complete activation map was acquired before AT terminated without energy delivery and could not be reinduced. PFA was subsequently performed during sinus rhythm using the stored activation map and electroanatomical geometry. Both patients remained asymptomatic, with no documented AT recurrence during 6- and 3-month follow-up, respectively. Conclusions These cases illustrate the technical feasibility of high-density mapping-guided regional PFA for focal AT arising from either atrial appendage.