Patient description: A 62-year-old African-American man presented with left upper and lower extremity weakness, associated with dark visual spot in right eye, right facial numbness, facial drop and slurred speech. He denied dyspnea, headache, palpitations, chest pain, fever, dizziness, bowel or urinary incontinence, loss of consciousness. His medical history was significant for hypertension, hyperlipidemia and hypothyroidism. He smokes cigarette 1 pack per day for 40 years and alcohol consumption of 5 to 6 beers per week. He is not aware about his family history. He is using Levothyroxine, Atorvastatin and HTCZ. His vital signs were stable in the primary evaluation. Left-sided facial droop, dysarthria, and left-sided hemiplegia were seen in the physical exam. His National Institutes of Health Stroke Scale (NIHSS) score was calculated as 7. Initial CT angiogram of head and neck reported no acute intracranial findings. Intravenous recombinant tissue plasminogen activator (t-PA) was administered as well as high-dose statin therapy. The patient was admitted to the intensive care unit to be monitored for 24 hours. MRI of the head revealed an acute 1.7-cm infarct of the right periventricular white matter and posterior right basal ganglia.

Clinical trial eligibility criteria: eligible ages (years): 18.0-85.0,  Ischemic Stroke Ischemic stroke symptoms with onset ≤ 3 hours* *or<4.5 hours according to local standard of care. Symptoms must be distinguished from another ischemic event such as syncope, seizure, migraine, and hypoglycemia. If the patient reports awakening with the event, the time of onset should be considered as last time the patient (or a witness to the patient's condition) considered herself/himself normal 85 years of age A clot causing complete or partial occlusion (TIBI 0, 1, 2, or 3) via TCD in any one of the following areas: distal iternal carotid artery (ICA), Meddle cerebral artery (MCA M1 or M2), posterior cerebral arteral (ICA P1 or P2), distal vertebral or basilar occlusions. TCD must be abnormal prior to the start of Argatroban. For patients without temporal windows (or in centers without emergent access to TCD), an abnormal CTA is required for enrollment (TIMI 0 or 1) Females of childbearing potential must have a negative serum pregnancy test prior administration of argatroban Signed informed consent by the patient or the patient's legal representative Meet for rt-PA therapy  Evidence of intracranial hemorrhage on baseline CT scan or non-vascular cause of neurologic deficit National institute health stroke scale (NIHSS) Level of Consciousness score ≥2 Baseline (immediately pre-Argatroban) NIHSS ≤ 5 or patient with rapidly resolving deficit or rapidly improving symptoms consistent with TPA Baseline NIHSS ≥15 for right hemisphere strokes and ≥20 for left hemisphere strokes Pre-existing disability with modified rankin scale (mRS) ≥ 2 CT scan findings of hypoattenuation of the x-ray signal (hypodensity)involving ≥ 1/2 of the MCA territory Any evidence of clinically significant bleeding, or known coagulopathy Patients currently on warfarin, with an elevated INR ≥ 1.5 Patients currently or within previous 48 hrs. on heparin with an elevated aPTT greater than the upper limit of normal Heparin flush required for an IV line. Line flushes with saline only