Asymptomatic Carotid Artery Stenosis

The goal of this observational study is to learn more about plaque biology in asymptomatic carotid artery stenosis (ACAS) patients through imaging. The main questions it aims to answer are: * To determine the ability of 64Cu-CANF-Comb positron emission tomography (PET) to risk stratify ACAS patients for stroke event, to include transient ischemic attack or remote ipsilateral intervention. * To further understand the role of Natriuretic Peptide Receptor C (NPRC) in the evolution of carotid atherosclerosis. Participants will be asked to undergo a carotid PET-magnetic resonance imaging (MRI) examination to assess whether the carotid atherosclerosis uptake of 64Cu-CANF-Comb as measured by PET-MRI correlates with patient outcomes (stroke, transient ischemic attack, or remote ipsilateral intervention).

This study is a multicenter, prospective, open-label, endpoint-blinded, randomized controlled trial designed to evaluate the safety and efficacy of endovascular stenting combined with optimal medical therapy versus optimal medical therapy alone in patients with asymptomatic severe stenosis (70-99%) of the internal carotid artery. The study plans to enroll 982 patients aged 40-80 years who have had no ipsilateral carotid artery-related neurological symptoms in the past six months and who have declined carotid endarterectomy. The primary endpoints include stroke, myocardial infarction, or death within 30 days post-procedure/enrollment, as well as the incidence of ipsilateral stroke from 30 days to one year post-procedure/enrollment. Secondary endpoints include procedural success rate, restenosis rate, changes in cognitive function, and others. The study results will provide high-level evidence-based medical evidence for the treatment selection of patients with asymptomatic carotid artery stenosis.