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 acute patients with a Large Core Infarction.

This trial aims to assess the effectiveness and safety of catheter-based focal intracranial hypothermia combined with endovascular reperfusion therapy for patients with acute patients with a Large Core Infarction. Participants were centrally randomized in a 1:1 ratio to either endovascular thrombectomy (EVT) combined with intra-arterial cold saline infusion (IA-CSI) (hypothermia group) or EVT combined with normothermic saline infusion (normothermia group).

Inclusion Criteria:

General Inclusion Criteria：

1. Age ≥18 years old.
2. The National Institutes of Health Stroke Scale (NIHSS) score was ≥6 points before randomization.
3. Time from symptom onset to randomization ≤24h.
4. 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.

Specific Neuroimaging Inclusion Criteria

1. Prior to randomization, CTA, MRA, or DSA confirmed the presence of anterior circulatory large vessel occlusion (internal carotid artery or M1segment).
2. NCCT ASPECTS value of 3 to 5 based on findings from non-contrast CT within 24 hours after stroke onset (defined as the time the patient was last known to be well), with no limitation with respect to infarct-core volume;
3. NCCT ASPECTS value of 0 to 2 based on findings from non-contrast CT within 24 hours after stroke onset and an infarct-core volume between 70 ml and 100 ml;
4. NCCT ASPECTS value greater than 5 based on findings from non-contrast CT after stroke onset and an infarct-core volume of 70 to 100 ml.

Exclusion Criteria:

1. Pre stroke mRS>1 score.
2. Multivessel Occlusion
3. Concomitant untreated intracranial aneurysms, intracranial tumors (with the exception of small meningiomas), or intracranial vascular malformations.
4. History of intracranial hemorrhage within 6 months, including parenchymal hemorrhage, intraventricular hemorrhage, or subarachnoid hemorrhage.
5. History of gastrointestinal hemorrhage, genitourinary bleeding, acute myocardial infarction (AMI), cranial trauma, or having undergone major surgical procedures within the past month.
6. The presence of active bleeding, severe anemia, coagulation dysfunction, or an uncorrected bleeding tendency (platelet count < 40,000 /μl, uncorrected INR>2.0).
7. 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.
8. Severe heart, liver, kidney disease.
9. Known allergy to contrast media or related medications.
10. Refractory hypertension uncontrolled by medication (defined as persistent systolic blood pressure >185 mmHg or diastolic blood pressure >110 mmHg).
11. glucose <2.8 mmol/L or >22.2 mmol/L；
12. Pregnancy or lactation；
13. the expected survival time is less than 12 months.
14. Participating in other clinical trials, in the investigational phase or in the follow-up phase.
15. Other conditions deemed by investigators to pose significant risks or render participation unsuitable (e.g. inability to comply due to psychiatric/cognitive/emotional disorders).