Abstract TP193: Atrial Fibrillation Burden Is Not Associated With Recurrent Cerebrovascular Events In Anticoagulated Stroke Patients: An Arest Trial Sub-study

Introduction: The burden of Atrial Fibrillation (AF) has previously been associated with a higher stroke risk in non-anticoagulated patients. We aim to find whether there is also an association between AF burden and recurrent cerebrovascular events in anticoagulated AF patients after their initial acute ischemic stroke (AIS) or transient ischemic attacks (TIA). Methods: The AREST study (Apixaban for Early Prevention of Recurrent Embolic Stroke and Hemorrhagic Transformation) was a multi-center, randomized controlled trial of early apixaban versus warfarin at one week post-TIA or two weeks post-AIS, in AF patients from 2015 to 2019. Subjects received either 30-day continuous electrocardiographic monitoring or an implantable device (i.e., pacemaker, loop recorder, or defibrillator). Logistic regression and Kendall's tau-b test were utilized to identify an association between AF burden and the proportion of subjects who developed recurrent cerebrovascular events. Results: Of 91 subjects enrolled into AREST, heart rhythm monitoring was assessed in 49 (54%); over half (59%) clustered at the extreme ends of the distribution, at either low (≤1%) or high (≥99%) AF burden. Higher AF burden was not significantly correlated with an increased risk of recurrent stroke or TIA (Odds Ratio = 0.99 [95% confidence interval (CI), 0.98-1.0]; p=0.518). Moreover, there was no statistically significant association between AF burden and the composite outcomes after adjusting for either apixaban or warfarin. Conclusions: AF Burden was not found to be associated with recurrent cerebrovascular events in patients taking oral anticoagulant after an AIS or TIA. Further research is needed to confirm these findings.