Abstract P713: Early Apixaban Therapy After Ischemic Stroke in Patients With Atrial Fibrillation

Abstract

Background: The optimal timing of anticoagulation after stroke in patients with atrial fibrillation (AF) is unknown. Patients and methods: A prospective, open label study (NCT04435418) of patients with AF treated with apixaban within 14 days of ischemic stroke/TIA onset was conducted. Baseline and follow-up CT scans were assessed for hemorrhagic transformation (HT) and graded using European Cooperative Acute Stroke Study (ECASS) criteria. The primary endpoint was symptomatic HT. Incident HT rates were assessed as Objective Performance Criteria. Results: One-hundred AF stroke patients, with a mean age of 79±11 years were enrolled. Median infarct volume was 4 (0.5-10.75) ml. Median time from index event onset to apixaban initiation was 2 (1-6) days, and median baseline NIHSS was 4 (1-9). Asymptomatic HT on baseline imaging was present in 15 patients. Infarct volume (OR= 1.1, [1.02-1.12], P <0.0001) and NIHSS (OR= 1.11, [1.03-1.20], P =0.007) were both associated with baseline HT. No patients developed symptomatic HT or systemic hemorrhage. Incident asymptomatic HT was seen on follow-up CT scan in 3 patients. Patients with incident HT were functionally independent (mRS=0-2) at 90 days. Recurrent ischemic events occurred within 90 days in 13 patients, 4 of which were associated with severe disability (mRS 3-5) and 4 with death. Discussion: Early apixaban treatment did not precipitate symptomatic HT after stroke. All HT was asymptomatic identified on imaging. Recurrent ischemic events were common and clinically symptomatic. Conclusions: Symptomatic HT rates are likely to be low in randomized trials of DOAC initiation post-stroke. Recurrent ischemic stroke may be the major clinical outcome.