High Coverage CARotid Stenting vs. Medical Management Alone to Prevent EmboliSm From symptomaTic Non-stenotic cARotid Disease (SyNC)

Other illness

• Patients in whom the stroke was likely caused by one of the following diseases:
• Small vessel disease
  • Large vessel atherosclerotic disease ≥ 50%
  • Cardioembolism
  • Other known disease e.g. vasculitis
• Patients with blood coagulation disorders
• Patients with known hypersensitivity to nickel-titanium
• Patients who are allergic to heparin
• Any known conditions that affect life expectancy to less than 12 months
• Any known conditions associated with an increased risk of endovascular treatment

Other

• Patients with acute complete occlusion of the carotid artery in an emergency setting
• Incidence of acute infarcts in other vascular (i.e., not ipsilateral carotid) territories
• Predominantly calcified Plaques (≥50% calcified plaque components on CT-Angio)
• Patients presenting with intraluminal carotid thrombus (e.g. characterized by 'donut sign' on CTA)
• Patients with highly tortuous vessels (\>90°) which may prevent access or safe insertion of the stent
• Patients with post-CEA re-stenosis or post-CAS re-stenosis
• Patients in whom access to the carotid lesion is impossible or associated with an increased risk of procedural complications
• Patients with lesions in the ostium of the common carotid artery
• Patients not able to visit the outpatient clinic for annual follow-up

• Patients diagnosed with acute ischemic stroke or acute retinal artery ischemia within the last two weeks related to symptomatic non-stenotic carotid disease (SyNC) and high-risk carotid plaque features
  • Ipsilateral acute ischemic stroke must be determined by acute ischemic infarct on DWI or CT OR
  • by neurological symptoms indicating ipsilateral cortical deficits consistent with ischemia in the territory of the internal carotid artery and after exclusion of a significant microangiopathy
  • Acute retinal artery ischemia must be determined by ophthalmologic examination
• Patients with no other identifiable cause of stroke, evaluated using standard echocardiographic examinations to exclude cardiogenic or aortogenic sources of embolism
• Symptomatic non-stenotic carotid disease defined as one or more plaques in the ipsilateral internal carotid artery causing 10-49% luminal narrowing AND
• Presence of high-risk plaque features which must be determined through visual inspection on CTA or MRI (Ultrasound findings alone are insufficient; features must be confirmed by CTA or MRI to meet the criteria):
  • Identification of at least two of the following characteristics Plaque thickness ≥ 3mm Irregular plaque surface Ulceration \<50% plaque calcification Lipid-rich necrotic core
  • and/or identification of at least one of the following characteristics Intraplaque haemorrhage
• Presence of carotid web characterized as shelf-like/linear, smooth filling defects
• Plaque assessment including evaluation of the presence of high-risk features by routine imaging (CTA, MRI) confirmed by an independent CoreLab
• Signed Informed Consent Form
• Patient ≥ 18 years
• mRS ≤ 3 at time of randomisation
• Dual antiplatelet therapy (DAPT) according to standard of care before endovascular treatment