Antithrombotic therapy for secondary Stroke prevention in patients with symptomatic large artery atherosclerosis and atrial fibrillation (FIB-CAS study) A single-center experience.

Introduction: Atrial fibrillation (AF) and large artery atherosclerotic diseases are major causes of ischemic stroke and their coexistence increases the risk of stroke and mortality. Research on antithrombotic strategies for AF patients with symptomatic large artery atherosclerosis is limited. This study aims to report a single center's experience regarding the antithrombotic regimens prescribed for this population and the association with stroke recurrence and hemorrhagic events.

Methodology: This retrospective cohort study included AF patients admitted to the Medical University of South Carolina with stroke due to symptomatic intracranial (sICAS) or extracranial atherosclerosis (sECAS). Patients were grouped based on prescribed antithrombotic regimens and compared according to their outcomes.

Results: Of 1,924 ischemic stroke patients with AF, 114 (6%) met the inclusion criteria. At discharge, the majority of patients were prescribed anticoagulants alone (sAC) or combined with a single antiplatelet (sAC + sAP) 26% and 34% respectively. Stroke recurrence was highest during the first 90-days after index stroke (11%). Patients on combination sAC + sAP had fewer recurrent strokes in the first 90-days compared to sAC (5.5% vs. 22.2%,p = 0.056) without significant increase in symptomatic hemorrhagic events (5.5% vs. 3.7%, p = 0.6). However the hemorrhagic risk significantly increased with prolonged therapy beyond 90-days (18% vs. 0%,p = <0.02). Early deaths were also high with 37% of total deaths occurring within 90-days after index stroke.

Conclusion: In this cohort, AF patients with stroke due to sICAS or sECAS had early stroke recurrence and mortality. While combination AC + sAP may reduce short-term stroke recurrence they may increase the hemorrhagic risk in the long-term.