The hypothesis of this study is that remote ischemic preconditioning (RIPC) might have a beneficial effect on outcomes of cerebral small vessel disease (CSV).

CSV constitutes an important type of ischemic stroke due to a generalized hypo-perfusion of brain. Few treatment methods are available except some beneficial effect shown with nimodipine. The potential treatment effect of RIPC on protection of brain from cerebral small vessel disease has not been investigated. The investigators designed this randomized, double-blind, controlled clinical trial to examine (1) whether RIPC has a beneficial effect on brain lesions of CSV, and (2) whether RIPC can protect patients of CSV from cognitive deterioration. There are 2 arms in this trial: One arm is RIPC treatment, the other one is sham RIPC treatment. Brain lesions will be quantified by volumetric MRI, and Xe-CT will be used to evaluate cerebral blood perfusion. Cognitive function will be evaluated by mini-mental state examination (MMSE) and the Montreal Cognitive Assessment (MoCA).

Inclusion Criteria:

1. Subjects aged 40-80 years;
2. Ischemic cerebrovascular event onset, if any, must be within 6 months;
3. TCD and carotid ultrasound exclude vascular narrow that can cause hemodynamic changes (usually >50% narrow lumen);
4. MRI confirmed the presence of lacunar infarction and / or generalized white matter lesions;
5. Written consent was obtained from the subject.

Exclusion Criteria:

1. History of intracranial hemorrhage;
2. Significant bleeding from other parts of the body;
3. History of atrial fibrillation;
4. History of myocardial infarction within six months;
5. Moyamoya disease or vasculitis;
6. Hereditary small vessel disorders, such as CADASIL, FABRY, and mitochondrial encephalo-myopathy;
7. Significant bleeding-coagulation dysfunction;
8. Abnormal blood pressure, glucose and/or lipids after restrict treatment regimen;
9. Severe liver/kidney disease, cancer or critical illness of internal medicine and surgery.