Comparison of cerebral safety after atrial fibrillation using pulsed field and thermal ablation: Results of the neurological assessment subgroup in the ADVENT trial

Atrial fibrillation (AF) ablation carries the risk of silent cerebral event (SCE) and silent cerebral lesion (SCL). Although "silent," these may have long-term clinical implications and are challenging to study as postprocedural magnetic resonance imaging (MRI) is not standard of care. The neurological assessment subgroup (NAS) of ADVENT compared cerebral effects of pulsed field ablation (PFA) with standard-of-care thermal ablation. The NAS included consecutive randomized PFA and thermal ablation patients who received postprocedural brain MRI 12–48 hours after ablation. Patients with apparent SCE or SCL findings underwent a modified Rankin scale assessment. MRI images were subsequently reviewed by a blinded brain imaging core laboratory. In total, 77 patients with paroxysmal AF were enrolled at 6 centers; 71 had analyzable scans (34 PFA; 37 thermal ablation). Through individual center review, 6 PFA and 4 thermal scans were identified as SCE/SCL positive, of which 3 PFA and 0 thermal SCE/SCL findings were confirmed by a blinded core laboratory. MRI findings revealed 1 patient with 2- to 4-mm SCEs, 1 patient with a 3-mm SCE, and 1 patient with 2 SCLs (5.5 mm and 11 mm). All modified Rankin scale and National Institutes of Health Stroke Scale scores were 0 before discharge and at 90-day follow-up. There were only 2 neurological safety events (1 transient ischemic attack [PFA] and 1 stroke [thermal ablation]) in the ADVENT study, neither of which was part of the NAS. The ADVENT trial provides the first prospective, randomized data on the cerebral impact of PFA and thermal ablation of AF. Incidence of SCE/SCL after ablation in the NAS was low.