Cerebrovascular ischemic lesions after pulsed field ablation for atrial fibrillation using variable-loop ablation catheter

Background Pulsed field (PF) energy is an increasingly adopted technology for ablation of atrial fibrillation (AF). Although clinical data on PF ablation is positive, data on ischemic cerebral lesions (ICL) after PF ablation is limited. Since the individual PFA systems differ substantially in pulse characteristics, cerebral safety should be studied separately for each system. Objectives To assess the incidence of ICLs after PFA for AF using a Variable-Loop Circular Catheter (VLCC). Methods The study was designed as a prospective, observational, cohort, single-center study. In non-paroxysmal AF patients, pulmonary vein and left atrial posterior wall isolation were performed. NIHSS scores were assessed within 24 hours post-ablation. Brain MRI (1.5T, diffusion-weighted imaging including) was conducted one day before and 24 hours after the procedure to detect acute ICL. The study initially aimed to enroll 40 patients but was terminated early due to safety concerns. Results Twenty-one patients were enrolled (age 66.1 ± 9.0 years, 38% females, all with non-paroxysmal AF). ICLs occurred in 14 (66.7%) patients, with a median of 2 (IQR 0–3) lesions per patient, and a median cumulative lesion burden of 10.5 mm (6.3–19.3). Most ICLs (28; 55.8%) were localized in the posterior territory. One patient experienced a transient ischemic attack, and one patient suffered a major peri-procedural stroke (NIHSS = 6; modified Rankin scale = 3 at the day 30 clinical follow-up). Conclusions PF ablation using VLCC was associated with a high rate of ICLs. More than half of the lesions were in the posterior cerebrovascular territory.