The purpose of this study is to assess the safety and efficacy of low dosage of Terazosin in Carotid Artery Stenting

Inclusion Criteria:

1. Symptomatic or asymptomatic carotid artery stenosis. In symptomatic patients the degree of stenosis should more than 50% (Based on NASCET Criteria), in asymptomatic patients the degree of stenosis should more than 70% (Based on NASCET Criteria);
2. Tolerance to any of the study medications, including TZ, clopidogrel, aspirin and statins;
3. Hypertensive patients with or without oral antihypertensive drugs
4. Can cooperate with and complete brain MRI examination;
5. Stable vital signs, cardiopulmonary, liver and kidney function was no obvious abnormalities;
6. Has a negative pregnancy test within 7 days before randomization and no childbearing potential;
7. Stable vital sign, normal renal and hepatic functions;
8. Informed consent.

Exclusion Criteria:

1. Evolving stroke;
2. Hemorrhagic tendency；
3. Severe dementia or Prior major ipsilateral stroke, if likely to confound study endpoints;
4. Chronic atrial fibrillation or any other Cardiogenic emboli source disease;
5. Myocardial infarction within previous 30 days;
6. Spontaneous Intracerebral Hemorrhage within the past 180 days, Hemorrhagic conversion of an ischemic stroke within the past 60 days or recent (<7 days) large area cerebral infarction has a hemorrhagic conversion tendence;
7. Any conditions that hampers proper angiographic assessment or makes percutaneous arterial access unsafe;
8. High risk candidates of CAS defined as the Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST);
9. Thiazides taken within 14 days before randomization;
10. Participating in any other clinical trial that has not completed the required protocol follow-up period;