Carotid Artery Disease

How carotid artery disease develops

Each carotid artery divides in the neck into an internal branch, which supplies the brain and eye, and an external branch, which supplies the face and scalp. Plaque tends to form at this division. Over years, cholesterol, inflammatory cells and calcium build up in the artery wall, narrowing the channel.

Carotid disease causes stroke mainly in two ways:

• Embolism: a fragment of plaque or a clot that forms on a rough plaque breaks off and travels into a brain artery.
• Reduced flow: severe narrowing or complete blockage reduces blood supply, especially if the other brain arteries cannot compensate.

Symptoms

Most people have no symptoms until a TIA or stroke. Symptoms come on suddenly and affect the side of the body opposite the diseased artery (or the eye on the same side):

• weakness, numbness or clumsiness of the face, arm or leg on one side
• difficulty speaking, finding words or understanding (when the dominant side is affected)
• amaurosis fugax: temporary loss of vision in one eye, often described as a shade or curtain, lasting seconds to minutes
• facial drooping

Use BE FAST to recognize a stroke: Balance loss, Eyes (vision loss), Face drooping, Arm weakness, Speech difficulty, Time to call 911.

A transient ischemic attack causes these symptoms briefly, often for under an hour, then they disappear. It is a major warning: the risk of stroke is highest in the following days and weeks.

Risk factors

• age over 65
• smoking
• high blood pressure
• high cholesterol
• diabetes
• obesity and physical inactivity
• coronary artery disease or peripheral artery disease
• family history of atherosclerosis
• previous neck radiation

Diagnosis

1. Listening to the neck: a bruit, a whooshing sound, suggests turbulent flow but is not reliable on its own.
2. Carotid duplex ultrasound: painless and quick; it measures the degree of narrowing and the speed of blood flow. It is the first test.
3. CT angiography or MR angiography: detailed images to confirm narrowing and plan treatment.
4. Brain imaging (CT or MRI): after a TIA or stroke to look for damage.
5. Heart tests: ECG and heart monitoring to look for atrial fibrillation, another common source of stroke.

Narrowing is graded by percentage. Narrowing of 50% to 69% is moderate; 70% to 99% is severe.

Should healthy people be screened?

The US Preventive Services Task Force recommends against routine screening of adults without symptoms, because treating narrowing found by screening may cause more harm than benefit in the general population. Screening may be considered for selected higher-risk people by their doctor.

Treatment

Medicines and risk factor control (for everyone)

• Antiplatelet medicines: aspirin or clopidogrel, sometimes both for a short period after a TIA or minor stroke.
• Statins: lower cholesterol and stabilize plaque, typically at high intensity.
• Blood pressure control.
• Diabetes management.
• Stop smoking.
• Exercise, healthy diet and weight control.

Procedures

For people who have had a TIA or stroke related to carotid narrowing of 50% to 99% (with the greatest benefit at 70% or more), a procedure reduces the risk of a further stroke. It should ideally be done within 2 weeks of symptoms.

• Carotid endarterectomy (CEA): surgery through a neck incision to open the artery and remove the plaque. It is the most established procedure.
• Carotid artery stenting (CAS): a stent placed through a catheter, usually from the groin.
• Transcarotid artery revascularization (TCAR): a stent placed through a small neck incision while flow is temporarily reversed to protect the brain.

For people without symptoms, procedures are considered only for severe narrowing in selected patients with low procedure risk and a reasonable life expectancy, alongside best medical therapy.

Complications

• stroke, the main concern
• TIA
• complications of procedures: stroke, heart attack, nerve injury causing hoarseness or tongue weakness, bleeding, and narrowing coming back

Outlook

With modern medical therapy, the yearly risk of stroke in people with asymptomatic narrowing is low. Prompt treatment after a TIA greatly reduces the risk of a major stroke. Carotid disease is a sign of atherosclerosis throughout the body, so controlling risk factors also protects the heart and legs.

Frequently asked questions

What are the symptoms of carotid artery disease?

Usually there are none until a TIA or stroke. Warning signs are sudden weakness or numbness on one side, facial drooping, trouble speaking, or temporary vision loss in one eye. Even if symptoms resolve quickly, call 911.

How is carotid artery disease diagnosed?

The first test is a carotid duplex ultrasound, a painless scan of the neck that measures narrowing. CT or MR angiography gives more detail before treatment. After a TIA or stroke, brain imaging and heart rhythm monitoring are also done.

When is carotid surgery needed?

Surgery or stenting is generally recommended after a TIA or stroke when the carotid artery on the affected side is narrowed by 50% to 99%, ideally within 2 weeks. It may be considered for severe narrowing without symptoms in carefully selected people.

Can a blocked carotid artery be cleared without surgery?

Medicines cannot remove existing plaque, but statins, antiplatelet drugs, blood pressure control and quitting smoking can stabilize it and greatly reduce stroke risk. Many people with narrowing and no symptoms are managed with medicines alone.

Can you live a normal life with carotid artery disease?

Yes. Most people with carotid narrowing live normally with medicines, lifestyle changes and regular monitoring. Knowing stroke warning signs and acting fast if they appear is essential.