Impact of Lesion Delivery and Irrigation Rates on Neurovascular Events With PFA for Atrial Fibrillation

An irrigated variable loop circular catheter (VLCC) for pulsed field ablation (PFA) is currently used in the United States to treat atrial fibrillation after a brief commercial pause to investigate neurovascular events (stroke and transient ischemic attack).

This study compared neurovascular events associated with pre-pause (Group I; 4 mL/min irrigation) and post-pause workflows using 4 mL/min (Group II_4cc) and 30 mL/min (Group II_30cc) irrigation settings with voluntarily reported complaint data.

The number of neurovascular events associated with VLCC procedures performed within the United States between December 2024 and August 2025 was retrospectively extracted from the manufacturer's complaint database. Total procedure volume was used to calculate neurovascular event incidence. Statistical analyses were performed to assess for any significant differences in procedural characteristics and patient outcomes.

Among 6,811 VLCC procedures, there were 132 Group I cases before the pause and 6,679 cases post-pause (Group II_4cc and Group II_30cc). The pre-pause neurovascular event rate of 3.0% decreased approximately 10-fold to 0.28% post-pause, coincident with a notable reduction in the number of ablations (Group I vs Group II_4cc/II_30cc, 32.6 ± 11.2 vs 21.2 ± 7.8). The neurovascular event rates for Group II_30cc vs Group II_4cc were 0.22% vs 0.39%, respectively (P = 0.213). There was no difference in neurovascular event rates between the pulmonary vein isolation-only cohort and the pulmonary vein isolation plus cohort (0.28% vs 0.29%; P = 0.929).

These data suggest that workflow factors may account for the 10-fold reduction in neurovascular events before vs after the commercial pause, namely by delivering fewer ablations (32.6 to 21.2) and avoiding stacking lesions.