Endarterectomy vs Stenting in Chinese Asymptomatic Carotid Stenosis Patients

Inclusion Criteria: Clinical Criteria

1. Age≥50 years，sex unlimited；

2. Asymptomatic carotid stenosis ，ie no transient ischemic attack、stroke or other relatedneurological symptom caused by carotid stenosis in the past 6 months.(Only theclinical manifestations of dizziness or mild headache are considered asymptomaticcarotid stenosis.)；

3. The patient understands the trial objective，understands and accepts the duration ofthe study，is able and willing to comply with all requirements，including follow-up andevaluation of it, voluntarily participates in the study and signs Informed ConsentForm. Anatomy Criteria

4. Internal carotid artery independent disease.（ Involving or not involving adjacentcommon carotid arteries is permitted.）；

5. Carotid stenosis satisfies one of the following criteria ：

6. Ultrasonography suggests stenosis ≥ 70%，or angiography showed stenosis ≥ 60%；

7. Ultrasonography suggests stenosis < 70%，but angiography or other examinationshowed stenosis in an unstable state；

8. Patients with bilateral carotid stenosis, the treatment time for target vesselcontralateral vessels is required 30 days before enrollment or 30 days aftercompletion of study procedure；

9. The stent can reach the site of lesion smoothly as expected.

Exclusion Criteria:

• Clinical Criteria

1. Patients with progressive stroke in the past 3 months or recent (Within 7 days)，CT or MRI suggested that the lesion is large，and may be with the risk ofhemorrhagic transformation；

2. Patients with anesthesia contraindications；

3. Serious ipsilateral stroke occurred in the past and may confuse the judgment ofthe study endpoint；

4. Patients with severe dementia；

5. Patients with spontaneous intracerebral hemorrhage in the past 12 months；

6. Large size of cerebral infarction or myocardial infarction occurred within 30days ；

7. Patients with large intracranial aneurysms (diameter> 5mm)，and cannot be treatedin advance or contemporaneous；

8. Chronic total occlusion without obvious cerebral ischemia symptoms；

9. Hemoglobin <100 g/l， Platelet count ＜125×109/L， INR＞1.5， Bleeding time > 1min，patients with exceeding the upper limits of normal，or heparin-relatedthrombocytopenia；

10. Patients unable to perform normal angiographic evaluation or unsafe percutaneouspuncture point；

11. Patients with neurologic disorder that caused transient or permanent neurologicaldeficits within 2 years before the surgery and can not be identified withtransient ischemic attack or stroke；

12. Patients with other cardiac emboli sources, such as left ventricular aneurysm,intraluminal filling defect, cardiomyopathy, aortic or mitral prosthetic heartvalve, calcific aortic stenosis, infective endocarditis, mitral stenosis, atrialseptal defect, atrial septal aneurysm, or left atrial myxoma；

13. Recent gastrointestinal bleeding and affects antiplatelet therapy；

14. Surgical contraindications or patients with high risk of surgery defined ashaving any of the following： It is known that two or more proximal or maincoronary artery stenosis ≥70%, untreated or unable to pass； Ejection fraction <30% or New York Heart Association (NYHA) functional class III or higher；Unstable angina，ie angina at resting state and electrocardiogram changes；Currently waiting main organ transplants (ie heart, lung, liver, kidney), or aredoing relevant evaluate； Malignant tumor or respiratory insufficiency, lifeexpectancy < 5 years or forced expiratory volume at one second < 30% (predicted)；Dialysis-dependent renal failure； Poor control of diabetes, fasting blood glucose >22mmol/L and ketone body > +2； Need to perform other general anesthesia duringthe same period；

15. There may be one or more anatomical conditions affecting the normal operativeapproach in patients with contraindications for carotid endarterectomy operation；there may be one or more anatomic situations to increase the risk of adverseevents in patients with high operative risk；including： Neck radiation therapyhistory； Radical neck surgery history； Inoperable lesions (ie more than C2lesions)； Spinal brake - unable to bend neck, or kyphotic deformity； Symptomaticdissection of the carotid siphon below； Common carotid artery openinglesion；present tracheotomy； Contralateral recurrent laryngeal nerve paralysis；Previously performed ipsilateral carotid endarterectomy，intracranial orsubclavian arterial bypass surgery； Contralateral carotid artery occlusion；Lesions series； Severe long segment calcification of the carotid artery；Inaccessible lesions by endoluminal methods (Severe distortion of the aortic archbranch, no suitable introduction of arteries, aortic arch anatomy special）；

16. Investigators consider the patient inappropriate to participate in this clinicaltrial；

17. Those who participated in clinical trials of other drugs or medical devicesbefore the inclusion did not reach the end of the time limit. Angiography criteria

18. Severe vascular tortuosity, or anatomical conditions may affect the safelocomotion of guide catheter, guide sheath or stent；

19. Patients with ipsilateral carotid artery stenting or having a graft；

20. Patients with severe or extensive arteriosclerosis, involving the aortic arch andthe proximal common carotid artery, causing locomotion danger of guide catheteror guide sheath；

21. Carotid endarterectomy contraindications by angiography：severity of intracranialor extracranial arterial stenosis that exceeds target lesions; cerebrovasculararteriovenous malformations; or other contraindications;

22. Patients with contralateral carotid artery stenosis, are expected to be performedwithin 30 days of the perioperative period of the study；

23. Occlusion.