Short‐Term Procedural Outcomes of Posterior Wall Isolation Using the Affera Pulse Field Ablation System

BACKGROUND: Posterior wall isolation (PWI) is often added to pulmonary vein isolation (PVI) for persistent atrial fibrillation (AF) and at redo ablation. Still, procedural performance with the Affera pulsed field ablation (PFA) platform is not well described. METHODS: We retrospectively analyzed consecutive patients who underwent PWI with the Affera Sphere-9 lattice-tip catheter from April to August 2025. Baseline characteristics and procedural data, including PWI time, number of lesions, and acute success, were analyzed. The primary procedural endpoint was acute PWI success. Secondary measures included time to PWI, number of applications, posterior wall area isolated, and complications. RESULTS: Forty patients underwent PWI (paroxysmal AF 13 [32.5%], persistent AF 27 [67.5%]). First pass PWI was achieved in 97.5%; overall acute PWI success was 100%. Median time to complete PWI was 7.0 min (IQR 5.1-11.0). Mean lesions for PWI were 19.6 ± 6.6, and the mean posterior wall area isolated was 12.9 ± 4.5 cm². Two minor vascular complications occurred (5.0%): one acute and one delayed femoral hematoma, both managed conservatively. After a median follow-up of 76 [58.5-121] days, 38/40 (95%) patients remained free from atrial arrhythmia. CONCLUSIONS: PWI with the Affera Sphere-9 system achieved 97.5% first-pass isolation with rapid, consistent procedural times. Further study of lesion durability and clinical outcomes is warranted.