Table 1.

Inclusion and Exclusion Criteria for the ARCADIA Trial.

Inclusion Criteria:
Age ≥45 years
Clinical diagnosis of ischemic stroke with brain imaging to rule out hemorrhagic stroke
Modified Rankin Scale score ≤4
Ability to be randomized no later than 120 days after stroke onset
Embolic stroke of undetermined source (see Table 2)
Exclusion Criteria:
Atrial fibrillation of any duration prior to randomization
Clear indication for treatment-dose anticoagulant therapy
Left ventricular ejection fraction <30%
Definite indication for antiplatelet agent
History of spontaneous intracranial hemorrhage
Chronic kidney disease with serum creatinine ≥2.5 mg/dL
Active hepatitis or hepatic insufficiency with Child-Pugh score B or C
Pregnancy risk
Known allergy or intolerance to aspirin or apixaban
Concomitant participation in another clinical trial involving a drug or intervention
Any condition that precludes follow-up or safe participation in the trial
Inability to obtain written, informed consent from patient or surrogate for trial participation