Timing Carotid Stent Clinical Study for the Treatment of Carotid Artery Stenosis（Timing Trial）

Inclusion Criteria: 1. Aged 18-85 years; 2. Patient is either symptomatic with carotid stenosis ≥50% OR asymptomatic with carotid stenosis ≥70% ; 3. Target lesion 3.5- 5.5 mm; 4. Signed informed consent. Exclusion Criteria: 1. Target lesion is not caused by atherosclerotic disease； 2. Target lesion is located at the opening of the common carotid artery； 3. Patient has severe lesion calcification that may restrict the full deployment of the carotid 4. Patient has a total occlusion of the target carotid arteries 5. Patient has a large number of acute or subacute thrombi and arteriovenous malformations near the target lesion 6. Patient has a severe stenosis or occlusion in series with target lesions 7. Patient has known severe carotid stenosis contralateral to the target lesion 8. Patient need angioplasty in other parts (including intracranial and extracranial) at the same time or within 30 days after procedure 9. Patient has a symptomatic severe stenosis of other blood vessels (including intracranial and extracranial) except carotid artery 10. Patient is experiencing (or has experienced) an evolving, acute, or recent disabling stroke or intracranial hemorrhage 11. Patient has a massive stroke or myocardial infarction 12. Patient has a intracranial aneurysm 13. Patient has a coagulation dysfunction or abnormal bleeding, or contraindications to heparin and antiplatelet drugs 14. Patient has known sensitivity to contrast agent 15. Patient has a platelet \< 90 × 109 / L, severe liver and kidney injury, and severe dysfunction of important organs such as heart, lung, liver and kidney 16. Patient has a uncontrollable severe hyperemia 17. Patient has a bradycardia 18. mRS≥3 19. Patient has life expectancy of less than one year 20. Patient is currently enrolled in another investigational study protocol 21. Females who are pregnant or in lactation 22. Other conditions not suitable for inclusion judged by the researcher -