Table of contents

Carotid artery stenosis



CAS refers to a progressive narrowing of the carotid artery.
CAS is primarily caused by atherosclerotic vascular disease.
Disease course
The development of atherosclerotic plaques in the carotid artery is associated with an increased risk of TIA and stroke.
Prognosis and risk of recurrence
The mortality rate at a mean follow-up of 4 years in adult male patients with high-grade asymptomatic CAS is approximately 37%.


Key sources

The following summarized guidelines for the evaluation and management of carotid artery stenosis are prepared by our editorial team based on guidelines from the European Society for Vascular Surgery (ESVS 2023,2019), the Society for Vascular Surgery (SVS 2022), the European Stroke Organisation (ESO 2021), the U.S. Preventive Services Task Force (USPSTF 2021), the European Society of Cardiology (ESC/ESVS 2018), and ...
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Screening and diagnosis

Indications for screening, general population
As per ESVS 2023 guidelines:
Do not obtain routine screening for asymptomatic CAS in the general population.
Consider obtaining selective screening for asymptomatic CAS to optimize risk factor control and medical therapy in patients with ≥ 2 vascular risk factors, mainly aiming to reduce late cardiovascular morbidity and mortality rather than identify candidates for carotid interventions.
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  • Indications for screening (before coronary/cardiac interventions)

  • Indications for screening (before AAA repair)

Diagnostic investigations

Carotid artery imaging: as per ESVS 2023 guidelines, obtain duplex ultrasound, CTA, and/or MRA in patients undergoing evaluation of the extent and severity of extracranial CAS.
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  • Cranial artery imaging

  • Vertebral artery imaging

  • Coronary artery imaging

Diagnostic procedures

Catheter-based contrast angiography: as per ESVS 2023 guidelines, do not obtain intra-arterial digital subtraction angiography in patients with atherosclerotic disease being candidates for revascularization unless there are significant discrepancies on noninvasive imaging.

Medical management

General principles: as per ESVS 2023 guidelines, ensure multidisciplinary team review to reach consensus decisions regarding the indications for carotid endarterectomy, carotid artery stenting, or optimal medical therapy in patients with CAS.

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  • Antiplatelet therapy

  • Anticoagulant therapy

  • Intravenous thrombolysis

  • Management of hypertension

  • Management of dyslipidemia

  • Management of diabetes mellitus

Nonpharmacologic interventions

Lifestyle modifications: as per ESVS 2023 guidelines, provide behavioral counseling to promote a healthy diet, smoking cessation, and physical activity in patients with asymptomatic or symptomatic CAS.

Therapeutic procedures

Mechanical thrombectomy
As per ESVS 2023 guidelines:
Consider performing surgical or endovascular removal of the thrombus in patients presenting with recent carotid territory symptoms and free-floating thrombus developing recurrent symptoms whilst receiving anticoagulation therapy.
Consider performing synchronous carotid artery stenting in the presence of poor antegrade internal carotid artery flow or poor collateralization via the circle of Willis after mechanical thrombectomy in patients with AIS undergoing intracranial mechanical thrombectomy with a tandem 50-99% CAS and a small area of ipsilateral infarction.

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  • Carotid artery stenting (asymptomatic patients)

  • Carotid artery stenting (symptomatic patients)

  • Timing of revascularization

  • Technical considerations for stenting (premedication)

  • Technical considerations for stenting (arterial approach)

  • Technical considerations for stenting (choice of stent)

  • Technical considerations for stenting (pre- and post-dilatation)

  • Technical considerations for stenting (cerebral protection)

Perioperative care

Perioperative antiplatelet therapy, carotid artery stenting: as per ESVS 2023 guidelines, initiate combination antiplatelet therapy with aspirin (75-325 mg daily) and clopidogrel (75 mg daily) in asymptomatic patients with CAS undergoing carotid artery stenting. Start clopidogrel (75 mg daily) at least 3 days before stenting or as a single 300 mg loading dose given in urgent cases. Continue aspirin and clopidogrel for at least 4 weeks after stenting and then continue antiplatelet monotherapy indefinitely.
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  • Perioperative antiplatelet therapy (carotid endarterectomy)

  • Perioperative antihypertensive therapy

  • Perioperative statin therapy

  • Perioperative neurological assessment

  • Management of perioperative hemodynamic instability

  • Management of perioperative stroke

  • Management of postoperative neck hematoma

Surgical interventions

Carotid endarterectomy, asymptomatic patients: as per ESVS 2023 guidelines, consider performing carotid endarterectomy in average surgical risk patients with an asymptomatic 60-99% stenosis in the presence of ≥ 1 imaging or clinical characteristics associated with an increased risk of late stroke, provided the 30-day stroke/death rate is < 3% and the life expectancy > is 5 years.

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  • Carotid endarterectomy (symptomatic patients)

  • Technical considerations for endarterectomy (anesthesia)

  • Technical considerations for endarterectomy (heparin reversal)

  • Technical considerations for endarterectomy (carotid exposure)

  • Technical considerations for endarterectomy (carotid sinus nerve block)

  • Technical considerations for endarterectomy (shunting)

  • Technical considerations for endarterectomy (high ICA lesions)

  • Technical considerations for endarterectomy (closure)

  • Technical considerations for endarterectomy (wound drainage)

  • Technical considerations for endarterectomy (completion imaging)

  • Extracranial-intracranial bypass surgery

Specific circumstances

Patients with AF
As per ESVS 2023 guidelines:
Obtain a comprehensive neurovascular workup with a multidisciplinary team review to decide between urgent carotid revascularization and anticoagulation alone in patients with a TIA or minor ischemic stroke in the presence of newly diagnosed or known AF and an ipsilateral 50-99% CAS.
Perform carotid endarterectomy or carotid artery stenting in patients started on anticoagulation (on the basis that cardiac embolism was considered the most likely cause of their TIA or stroke) but having recurrent events in the territory ipsilateral to a 50-99% CAS whilst on therapeutic levels of anticoagulation.

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  • Patients with carotid artery coils and kinks

  • Patients with carotid webs

  • Patients with ocular ischemia syndrome

  • Patients with common carotid/innominate artery disease

  • Patients with vertebral artery stenosis

  • Patients with coronary artery disease

  • Patients with AAA

  • Patients undergoing non-cardiac surgery (preoperative evaluation)

  • Patients undergoing non-cardiac surgery (timing)

  • Patients undergoing non-cardiac surgery (preoperative statins and antithrombotics)

  • Patients undergoing non-cardiac surgery (carotid revascularization)

Follow-up and surveillance

Follow-up imaging, medically treated patients: as per AANN/AANS/ACC/ACR/AHA/ASA/ASNR/CNS/SAIP/SCAI/SIR/SNIS/SVM/SVS 2011 guidelines, consider obtaining repeated duplex ultrasound annually by a qualified technologist in a certified laboratory to assess the progression or regression of disease and response to therapeutic interventions in patients with atherosclerosis who have had stenosis > 50% detected previously.
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  • Follow-up imaging (after revascularization)

  • Management of recurrent carotid stenosis

  • Management of carotid patch/stent infection

Quality improvement

Hospital requirements: as per ESVS 2023 guidelines, consider ensuring at least 12 carotid stent procedures per year (per operator) as an appropriate operator volume threshold in order to maintain optimal outcomes in patients undergoing transfemoral carotid artery stenting.
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  • Public health measures