The purpose of this study is to determine the safety and feasibility of remote limb ischemic conditioning(RIC) in acute ischemic stroke patients who received r-tPA thrombolytic therapy.

Inclusion Criteria:

• Male or female, age≥18;
• Acute ischemic stroke;
• modified Rankin Scale (mRS) score of 2-5;
• mRS score less than 1 before onset of stroke symptom;
• Onset of stroke symptoms within 4.5h before initiation of intravenous rt-PA thrombolytic therapy;
• Good compliance for Remote Ischemic Conditioning(RIC) therapy;
• Informed consent obtained.

Exclusion Criteria:

• Stroke or serious head trauma within the previous 3 months
• Major surgery or severe trauma with in the preceding 3 months
• Intracranial hemorrhage
• Systolic pressure greater than 185 mm Hg or diastolic pressure greater than 110 mm Hg, or aggressive treatment intravenous medication) necessary to reduce blood pressure to these limits
• Symptoms rapidly improving
• Symptoms suggestive of subarachnoid hemorrhage, even if CT scan was normal
• Gastrointestinal hemorrhage or urinary tract hemorrhage within the previous 21 days
• Arterial puncture at a noncompressible site within the previous 7 days
• Seizure at the onset of stroke
• Platelet count of less than 100,000 per cubic millimeter
• Received heparin within the 48 hours preceding the onset of stroke and had an elevated partial-thromboplastin time
• Received oral anticoagulation therapy preceding the onset of stroke and INR greater than 1.7 or prothrombin times greater than 15 seconds
• CT showed a multiple infarction (low density area greater than 1/3 cerebral hemisphere)
• Use or plan to use intervention for diagnosis or treating
• Intracranial neoplasm, cerebral aneurysm or arteriovenous malformation
• severe hepatic or renal dysfunction
• Contraindication for remote ischemic conditioning: severe soft tissue injury, fracture, or peripheral vascular disease in the upper limbs.
• Life expectancy<1 years
• Pregnant or breast-feeding women
• Unwilling to be followed up or poor compliance for treatment
• Patients being enrolled or having been enrolled