Approximately 17% of all patients with stroke are classified as having ESUS, which is associated with a considerable rate of stroke recurrence 4-5 % per year.

Despite recent scientific advances in acute ischemic stroke treatment in recent decades,consensus treatment of all guidelines is still ASA

This is an outcome assessor blind, randomized, parallel, placebo-controlled pilot study on ischemic stroke of undetermined source which will be conducted in Bu Ali Sina hospital in Sari, Iran.

Patients with recent stroke with criteria of ESUS, will be randomized to Rivaroxaban 2.5 mg BID plus ASA 80 mg daily or ASA 80 mg plus placebo (1:1 ratio) and have visit every 3 month until 1 year

Inclusion Criteria:

1. signing the inform consent

2. recent ischemic stroke ( 7-60) days with criteria of ESUS

3. only one risk factors of potential embolic source including:

   1. PTFV1 in standard ECG ≥0.05 mm.s or ≥0.005 mv.s
   2. LVH in standard ECG( Sokolow index≥ 35 mm) or on echocardiography
   3. Moderate or severe valvular disorder on echocardiography (except MS)
   4. PFO without indication of occlusion
   5. Left atrium enlargement in echocardiography

Exclusion Criteria:

1. History of hypersensitivity to the investigational medicinal product
2. Indication for anticoagulation
3. Indication for dual antiplatelet therapy
4. Contraindication to investigational medications
5. History of intracranial, intraocular, spinal, retroperitoneal or atraumatic intra-articular bleeding
6. Gastrointestinal bleed or major surgery within 3 months
7. Planned or likely revascularization (any angioplasty or vascular surgery) within the next 3 months
8. HAS-BLED score >3
9. Severe non-cardiovascular comorbidity with life expectancy < 3 months
10. Severe renal failure, defined as Glomerular Filtration Rate (GFR) <15ml/min, Dialysis, transplant, Cr >2.26 mg/dL
11. Severe hepatic insufficiency, Cirrhosis or Bilirubin >2x Normal or AST/ALT/AP >3x Normal
12. Modified Rankin Scale of >=4 at time of randomization or inability to swallow medications.
13. Hemorrhagic transformation of infarction detected by Brain CT or MRI at the time of drug application
14. Radiological or microbiological evidence of COVID-19 infection

Data will be available for researchers and scientific persons after request and review the proposal .