Ischemic post-conditioning is a neuroprotective strategy attenuating reperfusion injury in animal stroke models. The investigators have conducted a 3 + 3 dose-escalation trial to demonstrate the safety and tolerability of ischemic post-conditioning incrementally for a longer duration of up to 5 min × 4 cycles in stroke patients undergoing mechanical thrombectomy. This study aims to assess the infarct volume after ischemic post-conditioning in patients with acute ischemic stroke who are treated with mechanical thrombectomy.

Inclusion Criteria:

• Age ≥ 18 years;
• Acute ischemic stroke within 24 hours from stroke onset (or from time last known well) to groin puncture;
• Previous mRS ≤ 2;
• Baseline NIHSS ≥ 6;
• Baseline ASPECTS ≥ 6;
• With an occlusion of unilateral middle cerebral artery M1 segment/distal intracranial carotid artery;
• Successful recanalization (mTICI ≥ 2b) after thrombectomy confirmed by DSA;
• Written informed consent provided by the patients or their legal relatives.

Exclusion Criteria:

• Confirmed or clinically suspected cerebral vasculitis/fibromuscular dysplasia;
• Difficulty in reaching the designated position of the balloon used for ischemic post-conditioning;
• Stenting in the middle cerebral artery M1 segment/distal intracranial carotid artery during thrombectomy;
• > 2 times balloon dilations as rescue therapy due to angioplasty during thrombectomy;
• Moderate/severe residual stenosis (≥ 50%) in the offending artery after thrombectomy;
• Patients with contraindications to MRI;
• Other conditions that the investigator considered inappropriate for inclusion.