Vascular Surgery

Carotid Artery Stenosis

Atherosclerotic carotid stenosis can embolise to the retina or ipsilateral cerebral circulation; recent carotid-territory TIA or non-disabling stroke makes the lesion time-critical, with urgent imaging, best medical treatment and selected carotid endarterectomy.

In a nutshell

Carotid stenosis is usually asymptomatic; when symptomatic it causes retinal or ipsilateral cerebral embolisation. Give aspirin immediately for suspected TIA, arrange specialist assessment within 24 hours, use urgent carotid imaging for potential intervention and give best medical treatment to all. NICE recommends urgent endarterectomy referral for stable non-disabling stroke or TIA with symptomatic 50 to 99% NASCET or 70 to 99% ECST stenosis; UK services target treatment within 14 days.

Classic presentation

Sudden transient monocular visual loss or contralateral weakness, numbness or dysphasia from a recent carotid-territory TIA or non-disabling stroke.

Key points

The main mechanism is embolisation from an unstable carotid plaque; haemodynamic failure contributes in selected critical disease but is not the usual explanation.
A suspected TIA receives immediate aspirin unless contraindicated and specialist assessment within 24 hours; do not use ABCD2 to delay referral.
For suspected TIA, NICE advises no routine CT brain scan unless a CT-detectable alternative is suspected; consider same-day MRI after specialist assessment.
Urgent carotid imaging is required when a person with TIA may be a candidate for endarterectomy; imaging reports must state NASCET or ECST grading.
NICE recommends urgent CEA referral for stable non-disabling stroke or TIA with symptomatic 50 to 99% NASCET or 70 to 99% ECST stenosis; UK national practice targets treatment within 14 days.
Carotid endarterectomy is standard for suitable symptomatic patients; stenting is a selected MDT alternative, while asymptomatic stenting is restricted to special arrangements under NICE HTG704.
Best medical treatment applies to all grades and after any intervention: antiplatelet therapy, cholesterol lowering, blood-pressure and diabetes control, smoking cessation and lifestyle support.

First-line investigation

Immediate specialist TIA/stroke assessment followed by urgent carotid imaging when intervention is possible; duplex is commonly first-line with CTA or MRA for confirmation and planning.

Management

Treat TIA and stroke symptoms as time-critical

Give aspirin 300 mg immediately for suspected TIA unless contraindicated and arrange specialist assessment within 24 hours; persistent deficits need emergency stroke-unit assessment and imaging.¹

Confirm territory and quantify stenosis

Use specialist assessment, selective MRI for TIA, urgent carotid duplex and confirmatory CTA/MRA when intervention is possible; ensure NASCET or ECST grading is explicit.^1,5

Apply best medical treatment to all

Use antiplatelet treatment, lipid lowering, blood-pressure and diabetes control, smoking cessation and lifestyle intervention, coordinated with the vascular/stroke team around any procedure.^1,2,6

Revascularise only the right symptomatic patient

Refer urgently for CEA when stable non-disabling stroke or TIA is associated with symptomatic 50 to 99% NASCET or 70 to 99% ECST stenosis; consider stenting only as a selected MDT alternative and do not operate below the symptomatic threshold.^1,5,3

Prevent recurrence and safety-net new symptoms

Continue secondary prevention and vascular follow-up after medical treatment, CEA or stenting; any recurrent monocular visual loss, weakness, numbness or dysphasia is an emergency.^1,5,2

Exam traps

A carotid bruit is not a diagnostic test and its absence does not exclude important stenosis.
Do not send suspected TIA for routine CT brain imaging by default; follow the NICE specialist MRI/alternative-diagnosis pathway.
Do not delay suspected-TIA aspirin until a routine scan, but do not treat persistent neurological deficit as a TIA.
Never apply a stenosis percentage without checking whether the report uses NASCET or ECST criteria.
Do not make asymptomatic stenosis an automatic indication for endarterectomy or stenting; the benefit-risk balance differs from recent symptomatic disease.

Illustrations

Embolic mechanism of carotid stenosisDiagram showing plaque debris embolising from the internal carotid artery into the ophthalmic and middle cerebral arteries.PassFinals · original

Carotid endarterectomy plaque specimenExcised carotid-bifurcation specimen opened to show bulky yellow-white atherosclerotic plaque and haemorrhagic material removed during endarterectomy.Ed Uthman, MD, Wikimedia Commons · CC-BY-2.0

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.