Abstract 9576: Predictors of Silent Cerebral Events Detected on Magnetic Resonance Imaging in Patients After Atrial Fibrillation Ablation

Abstract

Introduction: Silent cerebral events (SCE) have been identified on magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation. Silent cerebral lesions represent irreversible cerebral damage, comparative analysis using a consistent MRI definition is missing and factors influencing the risk of SCE are poorly understood. Methods: 351 Patients undergoing AF ablation underwent post-ablation cerebral MRI. SCE were identified based on a sensitive definition using a 1.5Tesla MRI including DWI and ADC-map (but not including FLAIR). AF ablation was performed either using irrigated single-tip radiofrequency (RF) ablation (group 1, N=73), phased RF pulmonary vein isolation (PVI) (group 2, N=129), endoscopically-guided laser balloon (group 3, N=41), cryo-balloon PVI (group4, N=34) and irrigated RF multipolar catheters (nMARQ) (group 5, N=73). Differences in regard to SCE rates were analyzed. Results: In group 1 22%, in group 2 37%, in group 41%, in group 4 21% and in group 5 27% of patients had documented SCE. There was a significantly higher incidence of SCL in patients with compared to without exchanges of catheters over a single transseptal sheath (34% vs. 18%, p=0.007) and in patients with left atrial dilation (48% vs. 30%, p=0.01). In a subgroup analysis incidence of SCE was lower when patients were ablated under continued oral anticoagulation (11%) compared to novel oral anticoagulants (33%) or without continuous appropriate anticoagulation bridged with low-molecular weight heparin (45%). Documented left atrial low-voltage areas were associated with a higher incidence of SCE (46% versus 24% in the control group). Conclusions: When using a sensitive MRI definition of SCE incidences are relevantly higher compared to using the “old” definition including the FLAIR-sequence. Technology-associated and procedural characteristics associated with a higher risk of SCE have been identified. Modification of procedural steps of the AF ablation procedure may further reduce the risk of SCE.