Reperfusion With Hypothermia in Acute Ischemic Stroke

The primary objective of this study is to determine the feasibility and safety of receiving intravascular hypothermia treatment for patients experiencing endovascular treatment after acute ischemic stroke(AIS) due to a large vessel occlusion.

Hypothermia has been confirmed and widely applied in the treatment of coma patients after resuscitation from cardiac arrest, but its effect on the prognosis of patients with AIS is still controversial. Previous basic research has confirmed that hypothermia can significantly reduce the infarct volume and improve the survival rate and behavioral defects of mice by protecting ischemic brain tissue and improving reperfusion injury through a variety of ways. Therefore, we hypothesized that hypothermia can improve the prognosis of patients with AIS after reperfusion by improving reperfusion injury. This is a phase II clinical trial to to verify the efficacy and safety of endovascular hypothermia in these patients,This study enrolled patients with massive cerebral infarction after endovascular treatment recanalization, patients are divided into study group and control group. The study group received endovascular hypothermia for 12 hours following endovascular treatment and recanalization, and the control group received only usual medical treatment following endovascular treatment and recanalization. We will preliminarily explore the mechanism of endovascular hypothermia in successful reperfusion of large vessel occlusion AIS, and to provide reference for the design of future clinical trials.

Eligibility Criteria:
Inclusion Criteria:

* Aged 18-80 years;
* Patients with symptoms consistent with an AIS;
* Pre-stroke mRS score 0-1;
* NIHSS score 6-30 at the time of randomization;
* Computed Tomography Angiography (CTA) or Magnetic Resonance Angiography(MRA) proved occlusion of Internal Carotid Artery (ICA) terminal or M1 segment of Middle Cerebral Artery;
* Imaging showed massive infarction: within 24h of onset and Alberta Stroke Program Early CT Score (ASPECTS) \< 3, and large infarct core 70-100 ml (CT perfusion \[ Relative Cerebral Blood Flow (rCBF) \< 30%\]); within 24h of onset and ASPCECTS score 3-5 (based on NCCT); ASPECTS \> 5, within 6h-24h of onset,and large infarct core 70-100 ml (CTP \[rCBF \< 30%\]);
* Successful recanalization of occluded vessel (modified Thrombolysis in Cerebral Infarction (mTICI) scores 2b/3) after EVT;
* Patients and/or their families agreed to enter the trial.

Exclusion Criteria:

* CT after reperfusion showed PH2 hemorrhagic transformation;
* bilateral stroke or multiple intracranial occlusions;
* known presence of Inferior Vena Cava (IVC) filter;
* end-stage renal disease on hemodialysis;
* known hemorrhagic diathesis, coagulation factor deficiency or platelet count \< 5 × 109/L, International Normalized Ratio(INR) \> 1.7;
* known hypersensitivity to meperidine, buspirone, midazolam and other sedative and analgesic drugs;
* pregnant women;
* combined malignant tumors, sepsis, hypothyroidism;
* unstable vital signs/dying state, requiring vasoactive drugs to maintain hemodynamic stability and in the incremental phase;
* cardiac function grade 4/severe liver and kidney dysfunction;
* has participated in other drugs or device clinical trials that may have an impact on the current study;
* other reasons lead the investigator to believe that patients are not suitable to continue hypothermia treatment.