The purpose of this study is to explore the safety and efficacy of remote ischemic conditioning in patients with carotid artery stenosis undergoing carotid endarterectomy.

In this study, 100 patients with carotid artery stenosis undergoing carotid endarterectomy are included in our center in China according to the principle of random, and parallel control. The experimental group receive basic treatment and remote ischemic conditioning for 200mmHg, 2 times per day for 6 consecutive days. The control group receive basic treatment and remote ischemic conditioning control for 60mmHg, 2 times per day for 6 consecutive days. Two groups will be followed up for 1 year to evaluate the safety and efficacy of remote ischemic conditioning in patients with carotid artery stenosis undergoing carotid endarterectomy.

Inclusion Criteria:

1. Age≥18 years, <80 years, regardless of sex;
2. Symptomatic or asymptomatic carotid artery stenosis. In symptomatic patients the degree of stenosis should more than 50% (Based on North American Symptomatic Carotid Endarterectomy Trial Collaborators (NASCET) Criteria), in asymptomatic patients the degree of stenosis should more than 70% (Based on NASCET Criteria);
3. Baseline mRS 0-2;
4. Can cooperate with and complete brain magnetic resonance imaging (MRI) examination;
5. Signed and dated informed consent is obtained;

Exclusion Criteria:

1. Evolving stroke;
2. Chronic complete occlusion of the carotid artery without obvious symptoms of cerebral ischemia;
3. Severe dementia;
4. The causes of cardiogenic embolism, such as rheumatic mitral or aortic valve stenosis, artificial heart valves, atrial fibrillation, atrial flutter, sick sinus syndrome, left atrial myxoma, left ventricular wall thrombosis or valve tumor, congestive heart failure, bacterial endocarditis, etc;
5. Uncontrolled hypertension (defined as systolic blood pressure ≥ 180 mmHg or diastolic blood pressure ≥ 110 mmHg, despite medication taken at enrollment);
6. Severe hepatic and renal dysfunction (defined as aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≥3 times higher than the upper limit of the normal range, creatinine >265umol/l (3mg/dl));
7. The patients who have the contraindication of remote ischemic conditioning treatment, such as severe soft tissue injury, fracture or vascular injury in the upper limb. Acute or subacute venous thrombosis, arterial occlusive disease, subclavian steal syndrome, etc;
8. Pregnant or lactating women;
9. He/She is participating in other clinical research or has participated in other clinical research or has participated in this study within 3 months prior to admission;
10. Other conditions that the researchers think are not suitable for the group.