Inclusion Criteria:
1. Age is 18 years old or above.
2. Severe stenosis (70% - 99%) or occlusion of anterior intracranial circulation vessels, mainly including the intracranial segment of the internal carotid artery, middle cerebral artery (M1, M2) and anterior cerebral artery (A1, A2), which is confirmed by digital subtraction angiography (DSA), computed tomography angiography (CTA) or magnetic resonance angiography (MRA).
3. Patients with clinically diagnosed acute ischemic stroke who received remote ischemic treatment within 72 hours after the onset.
4. The NIHSS score ranges from 4 to 24.
5. The mRS score before stroke is less than or equal to 1.
6. informed consent.
Exclusion Criteria:
1. Patients with vessel recanalization after mechanical thrombectomy (TICI grade ≥ 2b).
2. Patients planning to receive intracranial endovascular treatment within 3 months.
3. Patients with cardiogenic embolism considered as the cause, such as rheumatic mitral or aortic valve stenosis, artificial heart valves, atrial fibrillation, atrial flutter, sick sinus syndrome, left atrial myxoma, left ventricular wall thrombus or valvular vegetations, congestive heart failure, bacterial endocarditis, etc.
4. Patients diagnosed with acute posterior circulation cerebral infarction.
5. Symptoms caused by non - culprit vessels.
6. Ipsilateral extracranial vessel stenosis ≥ 70%.
7. Systolic blood pressure \> 185 mmHg or diastolic blood pressure \> 110 mmHg, and uncontrollable by antihypertensive drugs.
8. Intracranial tumors, arteriovenous malformations or aneurysms.
9. Cerebral venous thrombosis or stenosis.
10. Any intracranial hemorrhage (parenchymal, subarachnoid, subdural, epidural) within 90 days before enrollment.
11. Severe coagulation abnormalities.
12. Any contraindications to remote ischemic conditioning: severe soft tissue injury, fracture or vascular injury of the upper limb, perivascular lesions of the distal upper limb, etc.
13. Patients with any serious diseases and a life expectancy of less than 1 year.
14. Patients who participated in other clinical trials within 3 months before enrollment or are currently participating in other clinical trials.
15. Patients who cannot be followed up (such as those without a fixed residence, overseas patients, etc.).
16. Pregnant or lactating women.
17. Patients who have previously received remote ischemic treatment or similar treatments.
18. Patients whom the researchers consider unsuitable for this clinical study.
