A multicenter, prospective, open-label, blinded-endpoint, randomized controlled trial to assess the effectiveness and safety of catheter-based focal intracranial hypothermia combined with endovascular reperfusion therapy for patients with acute anterior circulation large artery occlusion.

This trial aims to assess the effectiveness and safety of catheter-based focal intracranial hypothermia combined with endovascular reperfusion therapy for patients with acute anterior circulation large artery occlusion. This study used a stratified randomization method, with participants randomly allocated in a 1:1 ratio by a central network randomization system to either the mechanical thrombectomy (MT) combined with arterial selective cooling infusion (intravenous recombinant tissue plasminogen activator) (hypothermia) group or the MT combined with normal saline infusion (normothermia) group (hereinafter referred to as the hypothermia group or normothermia group). Randomization was stratified by ASPECTS score (≥8 or <8) and age (≥75 years or <75 years).

Inclusion Criteria:

1. Age ≥18 and ≤85 years old.
2. Symptoms of sudden focal or general neurological impairment.
3. There may be a causal relationship between vascular occlusion and nerve function defect.
4. Time from symptom onset to randomization ≤24h.
5. The National Institutes of Health Stroke Scale (NIHSS) score was ≥6 points before randomization.
6. According to the judgment of the clinician, the operation path is reasonable, and the operation and operation related instruments can reach the disease smoothly.
7. Patients or their guardians can understand the purpose of the trial, voluntarily participate and sign a written informed consent, and are capable of receiving clinical follow-up.
8. Prior to randomization, CTA, MRA, or DSA confirmed the presence of anterior circulatory large vessel occlusion (internal carotid artery or M1segment).
9. The symptoms are aggravated by recurrent cerebral infarction in the same drainage basin and/or the pathogenesis is caused by decreased blood perfusion.

Exclusion Criteria:

1. Pre stroke mRS>1 score.
2. There are acute infarcts in both cerebral hemispheres and/or anterior and posterior circulation.
3. NIHSS≤6 points.
4. Cerebral hemorrhage/subarachnoid hemorrhage was confirmed by CT or MRI. 5.The presence of active bleeding, severe anemia, coagulation dysfunction, or an uncorrected bleeding tendency (Presence of at least one of the following laboratory tests: hemoglobin < 10g /dl, platelet count < 100,000 /μl, uncorrected INR>1.5, PT> 1 minute above the upper limit of normal, or heparin-related thrombocytopenia).

6.Patients with heart function of grade 1 or above, or with a clear history of acute or chronic heart dysfunction, are at greater risk of acute heart failure or fluid perfusion intolerance as determined by clinicians.

7. Severe heart, liver, kidney disease. 8.With malignant diseases such as malignant tumors, the expected survival time is less than 3 months.

9.Participating in other clinical trials, in the investigational phase or in the follow-up phase.