Efficacy and Safety Study of Nimodipine to Prevent Mild Cognitive Impairment After Acute Ischemic Strokes

Inclusion Criteria: * 1\. Subjects between 30 and 80 years. * 2\. ICD-10 and CT/MRI criteria for acute cerebral infarction. * 3\. Stroke within 7 days after onset. * 4.based on years of education correction.MMSE\>17(illiteracy),MMSE\>20(primary school),MMSE\>24(others) * 5\. MoCA≤26 at baseline. * 6.Hachinski ischemic score ≥7 at baseline. * 7.Expected good compliance to study. * 8.Informed consent signed. Exclusion Criteria: * 1.Diagnosis of schizophrenia, major anxiety syndrome, major depression. * 2.Alzheimer disease, Parkinson disease, Huntington disease, and fronto-temporal dementia. * 3.Dementia caused by (e.g., central nervous system trauma, tumor, infections, metabolic disorders, normal pressure hydrocephalus, lack of folic acid or vitamin B12, or thyroid hormone deficiency). * 4.Contraindications to dihydropyridine derivatives. * 5.Aphasia or other diseases that affect cognitive evaluation. * 6.Serious arrhythmias, bradycardia (\<50 bpm) or tachycardia (\>120 bpm); myocardial infarction within the past 6 months; blood pressure \<90/60mmHg; severe renal or hepatic insufficiency; severe anemia, Hb\<100g/L; severe gastrointestinal disorders; tumor. * 7.History of epilepsy, use of the antiepileptic drugs. * 8.CT/MRI showed neurodegenerative changes or other lesions except cerebral ischemia.