Tests a stent in the neck artery plus medicine in people without symptoms

Who can take part

• Age 40-80 years
• Severe asymptomatic internal carotid artery stenosis (70-99%) confirmed by ultrasound/CTA/DSA
• Contralateral ICA stenosis <70%
• No TIA/stroke related to target lesion in past 6 months
• Declined carotid endarterectomy
• Willing to complete 12-month follow-up
• Signed informed consent by participant/legal representative

Who cannot take part

• Patients with larger intracranial aneurysms (diameter >5 mm) who cannot undergo prior or concurrent treatment
• The patient does not attend the clinical trial of other drug or medical device before enrollment
• Spontaneous intracranial hemorrhage in nearly one year
• Patients with transient or permanent neurological deficit resulting from Neurological deficits mimicking TIA/stroke from TIA or stroke
• Patients with severe dementia
• Myocardial infarction within 30 days
• Cardiogenic embolism, including left ventricular aneurysm, intraluminal filling defects, cardiomyopathy, aortic or mitral valve-prosthetic heart valve, calcified aortic stenosis, infective endocarditis
• Contrast allergy
• Ejection fraction <30% or New York Heart Association (NYHA) functional class III or higher; unstable angina, characterized by angina at rest with electrocardiogram changes
• Platelets <5 * 104 / uL, INR> 1.5, bleeding time> 1min or heparin-related thrombocytopenia; heparin is a contraindication to antiplatelet drugs; coagulopathy
• Poor controlled diabetes mellitus, fasting blood glucose> 22 mmol/L and ketone body>+2
• Severe liver and kidney function impairment, ALT> 3 times the upper limit of normal value or AST> 3 times the upper limit of normal value, blood creatinine increase> 2 times the upper limit of normal value
• Malignant tumor or respiratory insufficiency, and a life expectancy of <5 years
• The stenotic lesion exhibits severe circumferential calcification, defined as calcification greater than 3 mm in thickness visible in orthogonal views during fluoroscopy. (Note: In elderly subjects aged ≥70 years, anatomical factors such as tortuosity, arch anatomy, and calcification must be assessed more carefully)
• symptomatic internal carotid artery stenosis in the past 6 months
• Chronic occlusion without obvious symptoms of cerebral ischemic attack
• Common carotid artery ostial lesion
• Tandem lesions with severe stenosis of the ipsilateral intracranial artery
• Internal carotid artery dissection
• Internal carotid artery aneurysm
• Mitral stenosis, atrial septal defect, atrial septal aneurysm or left chamber myxoma
• Two or more proximal or main coronary artery stenosis 70%, untreated or recanable
• Other general anesthesia operations are required during the same period
• Pregnant or lactating women
• The investigator is not considered fit to participate in this clinical study; Imaging exclusion criteria:
• Type III aortic arch
• Severe angulation or tortuosity (≥90 degrees) of the common carotid artery or innominate artery that prevents safe and rapid placement of a guiding catheter or long sheath
• Severe angulation or tortuosity of the internal carotid artery that prevents safe deployment of an embolic protection device or stent. Severe tortuosity is defined as the presence of two or more angles ≥90 degrees within 4 cm of the stenotic lesion
• Stenosis of the beginning or proximal end of the common carotid artery, innominate artery, distal or intracranial segment of the internal carotid artery, and the stenosis degree is greater than that of the target stenosis