The goal of this clinical trial is to explore the influence of chronic RIC on collateral status evaluated by DSA in ischemic stroke patients with LAA etiology.
1. Age over 40 years old;
2. Diagnosed with ischemic stroke (including TIA and cerebral infarction), with onset time of more than 1 month;
3. Culprit arteries are the large arteries of the anterior circulation with atherosclerotic stenosis (≥50%) or occlusion;
4. ASITN/SIR collateral circulation of 0-3 based on DSA evaluation;
1) Patients with severe infection or serious diseases such as liver, kidney, hematopoietic system, endocrine system, etc.;
2) Patients with a history of stroke and severe sequelae (mRS≥3);
3) arterial stenosis due to aortic dissection, moyamoya disease; Any known vasculitic disease; herpes zoster, varicella-zoster or other viral infections with vascular lesions; neurosyphilis; other intracranial infections; any intracranial artery stenosis associated with hypercytosis of cerebrospinal fluid; radiation-induced vascular lesions; myofiber dysplasia; sickle cell disease; neurofibromas; benign vascular lesions of the central nervous system; postpartum vascular disease; stenosis of the intracranial arteries due to vasospasm or thrombosm;
4) Uncontrolled severe hypertension (systolic pressure≥180mmHg or diastolic pressure≥110 mmHg after drug treatment) ;