A Trial of Intravascular Hypothermia Therapy in Acute Ischemic Stroke Patients

Inclusion Criteria: 1. Age between 18 and 80 years old 2. Clinical signs consistent with acute ischemic stroke with large vessel occlusion in the anterior circulation (internal carotid artery, middle cerebral artery M1 or M2 segment) 3. ASPECTS score 0-10 4. Arterial puncture could be performed within 24 hours from symptom onset or LKN 5. Baseline NIHSS (NIHSS) score prior to randomization ≥ 10 and NIHSS 1a ≥ 1 6. Candidate for endovascular thrombectomy therapy in accordance with best practices per AHA standard stroke guidelines meeting all labeling requirements for EVT in the trial 7. Successful recanalization of occluded vessel (mTICI 2b-3) after EVT 8. No intracranial hemorrhage postoperative CT examinations immediately after recanalization. If the subject' recanalization of vessel could not achieve mTICI 2b-3, the subject could not enter the per-protocol analysis and will separate another group 9. Informed consent form signed by subjects or their legal guardian Exclusion Criteria: 1. Subject who suffer serious infection (e.g. sepsis) or multiple organ failure 2. Known presence of an IVC filter 3. End stage renal disease on hemodialysis 4. Known hypersensitivity to antiplatelet agents, anticoagulation drugs, iodinated contrast and/or anesthetics 5. Known hypersensitivity to the components of the medical device 6. Any known history of the following conditions: bleeding diathesis, coagulopathy, cryoglobulinemia, sickle cell anemia, will refuse blood transfusions or contraindication to heparin; history of genetically confirmed hypercoagulable syndrome 7. Use of warfarin with INR \> 3 8. Hemodynamically significant cardiac dysrhythmias (eg. QTc interval \>450 msec, bradycardia (heart rate less than 50), Mobitz Type II second degree AV block (or higher AV block), and severe ventricular dysrhythmias (sustained VT or VF)) which cause significant hypotension (SBP ≤ 120 mmHg requiring more than two pressor medications) 9. Platelet count\<40×10\^9/L 10. Blood glucose concentration \<2.7 or \> 22.2 mmol/L 11. Hypertension uncontrollable by drug treatment (systolic blood pressure≥185 mmHg or diastolic blood pressure≥110mmhg) 12. Expected life expectancy\<6 months 13. Temperature \< 35°C on admission to Emergency Department 14. With a pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations (e.g., dementia or mental illness) 15. Subject participating in a study involving an investigational drug or device that would impact the current study 16. Baseline CT/MR evidence of multiple vascular territory acute stroke 17. Baseline CT/MR showing evidence of arterial vasculitis or dissection 18. Evidence of intracranial hemorrhage or hemorrhagic transformation before thrombectomy 19. Evidence of intracranial hemorrhage or hemorrhagic transformation immediately after thrombectomy 20. Presence of pulmonary embolism, ilio-femoral or deep vein thrombosis 21. Brain vascular lesion (e.g. aneurysm or arteriovenous malformation) 22. Brain tumor or CNS infection 23. Concurrent participation in a study involving an investigational drug or device that would impact the current study 24. Female patient of childbearing potential who is known to be pregnant or lactating 25. For other reasons, the researchers believe that the patient is not suitable for continued treatment 26. Patients without a legally authorized representative to sign the consent form will be excluded