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

BACKGROUND Atrial fi brillation (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. OBJECTIVE The neurological assessment subgroup (NAS) of ADVENT compared cerebral effects of pulsed fi eld ablation (PFA) with standard-of-care thermal ablation. METHODS 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 fi ndings underwent a modified Rankin scale assessment. MRI images were subsequently reviewed by a blinded brain imaging core laboratory. RESULTS 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 fi ndings were confirmed by a blinded core laboratory. MRI fi ndings 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. CONCLUSION The ADVENT trial provides the fi rst 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.