Prospective, multicentric, multispecialty, international, open-label, single arm study using per-protocol intravascular ultrasound [IVUS, 20MHz electronic phase-array transducer] to document the procedure result of an effective plaque exclusion from the vessel lumen.

Investigator initiated, academic, single arm, open-label, non-randomized, prospective, multicenter, multispecialty trial of CGuard™ use in all-comer population of consecutive patients with carotid stenosis related cerebral symptoms (TIA, stroke, retinal TIA, retinal stroke) or signs of ipsilateral brain injury on MRI or CT imaging.

The main objective of this observational study is to evaluate an incidence of residual plaque prolapse after carotid stenting using the study device.

Study Rationale In conventional carotid stents, plaque prolapse (PP) on intravascular imaging had been determined to be strongly associated with new post-procedural diffusion-weighted magnetic resonance lesions on cerebral imaging and with increased ischaemic stroke incidence. A significant increase in PP susceptibility was observed with unstable carotid plaque, pointing to the limitations of conventional CAS in unstable carotid plaques, such as symptomatic and increased-spontaneous-symptoms-risk lesions.

This is reflected in current guidelines that provide a higher recommendation class to surgical management (CEA) rather than CAS for symptomatic lesions.

Circumstantial evidence indicates that the novel carotid stent covered with MicroNET (CGuard EPS) may be an optimal device for effective carotid plaque sequestration (that may be particularly relevant in high-risk plaques) - but no systematic study has been performed thus far.

Because of the increasing evidence that not only clinical symptoms (that may be related to for instance the affection of dominant vs. non-dominant haemisphere) but also signs of ipisilateral cerebral infarct/s are a hallmark of high-risk plaque and are associated with adverse prognosis, and because that neurology increasingly uses the term "symptomatic" to refer to carotid stenosis associated with clinically silent ipisilateral cerebral infarct/s, the present study will enroll both patients with clinical symptoms of cerebral ischaemia in relation to carotid stenosis and those with (clinically silent) signs of ipsilateral injury such as ischemic focus/foci on CT or MRI/DW-MRI).

As previously demonstrated, clinically significant/relevant PP is that depicted by IVUS (with angiography, on the one hand, being not sensitive enough and OCT, on the other, being possibly too sensitive).

Inclusion Criteria:

• All consecutive patients with clinically symptomatic carotid stenosis , or carotid stenosis associated with ipisilateral cerebral ischemic infarct/s on CT or MRI/DWI imaging, referred and accepted by the study center for CAS as per local standard referral pathways and study center routine.
• Patient informed consent to participate.
• Patient accepts follow-up scheme and consents to follow-up visits.

Exclusion Criteria:

• Lack of indication to carotid revascularization as per current ESC/ESVS Guidelines, or any clinical or angiographic or other contraindication to CAS (such as renal failure defined as creatinine level > 2.5 mg/dL or eGFR <20 ml/kg min, or incompatibility with DAPT).
• Surgery within the preceding 30 days or planned surgery within 30 days after CAS.
• Life expectancy <1 year (eg. neoplastic disease).
• MI within 72h prior to CAS.
• Known coagulopathy.
• History of cerebral stroke with documented/known cause other than carotid disease.
• Atrial fibrillation or flutter.
• Any known cause for potential cerebral embolization different than carotid stenosis.
• History of intracranial bleeding.
• Any contraindications to as per IFU study device implantation.

Consecutive clinically-symptomatic patients (ipsilateral cerebral or retinal stroke or TIA with the preceding 6 months) with atherosclerotic de novo carotid artery stenosis causing at least 50% lumen reduction by quantitative carotid catheter angiography (QCA) or carotid stenosis of at least 50% lumen reduction by QCA in relation to documented ipsilateral ischaemic brain lesions/infarct on CT or MRI.