Carotid artery disease, a narrowing of the neck arteries to the brain

Dr Desmond Ooi, a vascular surgeon, treats carotid artery disease, a narrowing of the two main arteries in the neck.

A narrowed carotid artery often causes no symptoms, yet it can lead to a stroke.

What carotid artery disease is

The carotid arteries are two large arteries, one on each side of the neck.

They carry blood to the eyes and the front of the brain.

In carotid artery disease, deposits of fat and calcium, called plaque, build up inside the artery wall.

The narrowing this causes is called carotid artery stenosis, or carotid stenosis.

How a narrowed carotid artery can lead to a stroke

Small clots and pieces of plaque can break off the narrowing.

They are carried up into the eye or the brain, where they block a small artery.

A short block causes a mini-stroke, also called a transient ischaemic attack (TIA).

Its signs are the same as a stroke's, but they pass within minutes, and always within 24 hours.

After a mini-stroke, the risk of a stroke is highest in the next 7 to 14 days.

Symptoms of a blocked carotid artery, and when to call 995

A narrowed carotid artery often causes no symptoms.

For some people, the first sign is a mini-stroke or a stroke.

The symptoms of carotid artery blockage come on suddenly:

• Face, arm or leg: weakness or numbness, or a face that droops
• Speech: slurred words, or trouble finding or understanding words
• Sight: blurred or lost vision, sometimes in one eye only, or double vision
• Swallowing: trouble swallowing food or drink
• Balance: sudden unsteadiness, or a feeling that the room is spinning

If the signs have already passed, see a doctor the same day, because a mini-stroke can come before a stroke.

Who is more likely to have a narrowed carotid artery

Three things make a narrowing more likely:

• Smoking: it makes a severe narrowing more likely, and helps plaque grow.
• High blood pressure: it makes a narrowing more likely, and treating it slows a narrowing's growth.
• Diabetes: people with diabetes are more likely to have a narrowing.

Carotid artery screening of everyone is not advised.

For people with two or more risk factors for artery disease, a scan may be considered, mainly to get their medicines and risk factors right.

How carotid artery disease is found

A duplex ultrasound scan of the neck shows the narrowing and measures how tight it is.

It uses sound waves, so there is no needle and no X-ray.

A CT or MRI scan of the arteries may follow, before any treatment is planned.

For people without symptoms, the scans also look for signs of a higher stroke risk:

• a narrowing that has become tighter since the last scan
• a large or soft plaque
• signs on a brain scan of an earlier, silent stroke

How carotid artery stenosis is treated

Everyone with a narrowing is advised to change their lifestyle and to take medicines, whether or not they have symptoms.

• Stopping smoking, eating well and moving more: these lower the risk of a mini-stroke or stroke.
• Antiplatelet tablets: these thin the blood and make clots on the plaque less likely.
• Statins: these lower cholesterol and help prevent stroke and heart attack over the long term.
• Blood pressure treatment: for anyone whose blood pressure is high.

Some people also need an operation or a stent:

Who may need carotid endarterectomy or stenting

The choice depends on whether the narrowing has caused symptoms, and how tight it is.

• After a mini-stroke or stroke: a narrowing of 70% or more is usually treated with an operation, and one of 50% to 69% may be.
• How soon: as soon as possible, ideally within 14 days of the symptoms.
• Which one: in those first 14 days, and for people aged 70 or over, the guideline prefers endarterectomy; for younger people, stenting may be an alternative.
• With no symptoms: most people are advised medicines and lifestyle changes alone.
• With no symptoms, but signs of a higher stroke risk: an operation or a stent may be considered for a narrowing of 60% or more.

The newest large trial, published in 2026, studied people with a narrowing of 70% or more and no recent symptoms.

Adding an operation did not make a significant difference (1,240 people).

A 2026 analysis argues that the operation may also show a benefit with longer follow-up, so advice for people without symptoms may change.

Which of these suits you depends on your symptoms, the scans, your general health and your own choice.

Questions about carotid artery disease