OVERVIEW

What is carotid artery stenosis?

The carotid artery is the primary blood vessel supplying the head, with one on each side of the neck. Carotid artery stenosis refers to a condition where the lumen of the carotid artery narrows due to various causes (such as atherosclerosis, arteritis, etc.), leading to insufficient blood flow and resulting in severe cerebral ischemia.

Carotid artery stenosis is a significant cause of ischemic stroke and transient ischemic attacks in the elderly, accounting for 15–20% of all ischemic strokes.

Severe cases may lead to ischemic stroke, commonly known as a "stroke," severely impairing the patient's ability to function and even making daily self-care impossible.

Is carotid artery stenosis common?

• Among the elderly, the prevalence of carotid artery stenosis is 26.7%–31.8%, with 7.7% experiencing severe stenosis (>70%).

• In individuals over 50 years old, the prevalence of moderate or higher asymptomatic carotid artery stenosis is 5%–7.5%, while severe asymptomatic stenosis occurs in about 3% of cases.

SYMPTOMS

What are the symptoms of carotid artery stenosis?

Carotid artery stenosis primarily causes cerebral ischemia symptoms, which may include tinnitus, blurred vision, dizziness, headaches, memory loss, drowsiness or insomnia, and frequent dreaming.

It may also present with symptoms of transient ischemic attacks, such as vertigo or temporary vision loss. Severe cases may involve episodic syncope, hemiplegia, aphasia (inability to speak), or even coma. A small number of patients may experience vision decline, diplopia (double vision), or sudden blindness.

What is symptomatic carotid artery stenosis?

Symptomatic carotid artery stenosis refers to cases where patients have experienced transient (temporary) or permanent neurological symptoms within the past 6 months, including:

• Temporary vision loss on the same side as the carotid stenosis;

• Numbness in the limbs or face on the opposite side of the carotid stenosis;

• Visual field defects (reduced or missing areas of vision);

• Aphasia (inability to speak), etc.

CAUSES

What are the main causes of carotid artery stenosis?

The primary cause of carotid artery stenosis is atherosclerosis, a common and prevalent condition that often leads to cardiovascular and cerebrovascular events such as coronary heart disease and stroke.

Atherosclerosis is the "number one killer" threatening human health, accounting for 40% to 50% of total deaths. Another cause is Takayasu arteritis, a chronic inflammatory disease affecting the aorta and its major branches.

How does carotid atherosclerosis develop and progress?

• Carotid atherosclerosis is a chronic, long-term vascular inflammatory condition. It begins in childhood and develops throughout adulthood. The arterial wall gradually accumulates lipids, hardens into fibrous plaques, or develops composite lesions, resulting in three types of pathological changes.

• Damaged arteries lose elasticity and become brittle. Plaques on the arterial wall are prone to rupture, forming blood clots at the rupture site, which significantly reduce or suddenly block blood flow in the already narrowed artery.

• If small emboli break off and block small arteries, they can cause transient ischemic attacks (often manifesting as sudden blackouts or brief loss of consciousness) or "stroke" (thrombotic cerebral infarction).

Which groups are more susceptible to carotid artery stenosis?

Depending on the cause, carotid artery stenosis tends to occur in different populations.

• Carotid stenosis caused by atherosclerosis: More common in middle-aged and elderly individuals, particularly males.

• Carotid stenosis caused by Takayasu arteritis: Takayasu arteritis is a chronic, nonspecific inflammatory disease of large arteries. It is more common in adolescents, especially females. Early symptoms may include general discomfort, fatigue, fever, loss of appetite, excessive sweating, and weight loss. Vascular stenosis or occlusion leads to ischemic symptoms in tissues or organs.

What is the relationship between carotid artery stenosis and steal syndrome?

The left and right internal carotid arteries supply blood to the brain and eyes. When one internal carotid artery is blocked, the other artery cannot remain passive—it gradually increases blood supply (via collateral branches from the internal carotid or vertebrobasilar arteries) to compensate for the blocked side. For the unaffected side, this is akin to having blood and nutrients "stolen," a phenomenon called "steal syndrome." Initially, if the blood supply is sufficient, symptoms may not appear.

If the unaffected side already has poor blood supply (e.g., due to arterial stenosis), diverting some blood to the blocked side can lead to insufficient blood flow, known as steal syndrome. Patients often experience dizziness, headaches, unsteady gait, blurred vision, hearing loss, and occipital pain.

DIAGNOSIS

What physical examinations are performed for the diagnosis of carotid artery stenosis?

• First, the doctor will palpate the pulses of the bilateral carotid arteries. In cases of stenosis, the carotid artery pulse is usually weakened or absent.

• Next, the doctor will auscultate the carotid arteries for abnormal murmurs.

• Afterward, the doctor will further assess the condition of blood vessels in other parts of the body and may conduct a neurological examination to evaluate the degree of ischemia in the brain and other organs.

What examination methods are available for carotid artery stenosis?

Common clinical examinations include:

• Digital subtraction angiography (DSA, a special imaging test for blood vessels);

• Color Doppler duplex ultrasound;

• Doppler ultrasound blood flow examination;

• Magnetic resonance angiography (MRA) and contrast-enhanced CT (CTA);

• Intravascular ultrasound;

• Fundus examination;

• X-ray plain film;

• Blood tests, etc.

Considering cost and invasiveness, color Doppler ultrasound, contrast-enhanced CT (CTA), and DSA are particularly commonly used.

Why do doctors perform ultrasound examinations for carotid artery stenosis?

Carotid artery ultrasound can assess the degree of atherosclerotic vascular stenosis, the extent and acoustic characteristics of plaque involvement, and the morphological features of plaques. These findings provide important reference value for subsequent surgical decisions.

If the doctor is considering carotid endarterectomy, the focus will be on observing structural changes in the affected lumen, which helps objectively evaluate the feasibility of surgery.

How is carotid artery stenosis diagnosed?

Generally, clinicians can make a preliminary diagnosis of carotid artery stenosis based on clinical manifestations and auxiliary examinations, and they can also make an initial assessment of the cause.

However, arteriography (i.e., DSA) is essential for confirming the diagnosis of carotid artery stenosis and formulating a treatment plan. To determine the exact cause, pathological examination of the blood vessels is required.

TREATMENT

Which department should I visit for carotid artery stenosis?

Once symptoms of cerebral ischemia appear, such as tinnitus, blurred vision, dizziness, headache, memory loss, vertigo, or excessive dreaming, immediate attention is required. Many people may first visit the neurology department or emergency department. If carotid artery issues are confirmed, they may be referred to vascular surgery, interventional radiology, neurosurgery, or general surgery.

If carotid artery stenosis is detected during a physical examination, it is recommended to go directly to the vascular surgery outpatient clinic for specialized physical and auxiliary examinations to achieve early diagnosis and treatment and prevent serious complications.

What are the treatment options for carotid artery stenosis? What is the goal of treatment?

The main treatments for carotid artery stenosis include conservative therapy, surgical treatment, and interventional therapy. The goal is to improve cerebral blood supply, alleviate symptoms of cerebral ischemia, and prevent stroke.

What are the conservative treatment methods for carotid artery stenosis?

Conservative treatments for carotid artery stenosis mainly include:

• Improving blood and oxygen supply and energy metabolism: anticoagulation and antiplatelet aggregation, vasodilation therapy with papaverine and nimodipine, prostaglandin E1 and defibrase drugs, and the use of energy mixtures and hyperbaric oxygen chambers;
• Medications targeting the underlying cause (e.g., statins for lipid reduction).

What surgical methods are available for carotid artery stenosis?

Surgery aims to remove tissues or lesions causing carotid artery lumen stenosis and restore normal blood flow (revascularization).

The main surgical methods are:

• Carotid endarterectomy;
• Carotid eversion endarterectomy.

When should carotid artery stenosis patients undergo surgery?

Surgery is recommended in the following cases:

• Symptomatic patients: If auxiliary examinations show stenosis >70% or angiography shows stenosis >50%, with a perioperative (around the surgical process, from preoperative 5–7 days to postoperative 7–12 days) stroke or mortality rate <6%, carotid endarterectomy is recommended;
• Asymptomatic patients: If stenosis exceeds 70% with low perioperative stroke and mortality rates, carotid endarterectomy is advised;
• Elderly patients or those with contraindications for interventional therapy should consider carotid endarterectomy;
• Patients with transient ischemic attacks or strokes within the past 2 weeks, without contraindications, should undergo early vascular reconstruction.

When should carotid artery stenosis or occlusion patients avoid surgery?

Surgery is not recommended for:

• Patients with stenosis <50%;
• Chronic total occlusion of the affected vessel;
• Patients with severe brain dysfunction;
• Patients unsuitable for neck surgery—interventional therapy (carotid artery stenting) is preferred.

What complications may occur after carotid artery stenosis surgery?

Possible complications include:

• Neck nerve injury, carotid bifurcation damage, shunt-related complications, postoperative carotid dissection, hyperperfusion syndrome, stroke, carotid thrombosis, postoperative hypotension/hypertension, restenosis, or incision hematoma;
• Other risks: cardiovascular complications, internal carotid artery spasm, distal embolism, stent thrombosis, external carotid occlusion, dissection, perforation, device failure, or restenosis.

Are there minimally invasive treatments for carotid artery stenosis?

Yes, interventional therapy is a minimally invasive option:

• A catheter is inserted through the skin into the artery to deliver a balloon or stent, expanding the narrowed vessel to restore blood flow;
• It is less invasive, simple, repeatable, and often preferred for severe cases or high-risk patients.

How can risks of interventional therapy for carotid artery stenosis be reduced?

Measures include:

• Preoperative antiplatelet drugs;
• Intraoperative balloon pre-dilation with slippery guidewires;
• Use of cerebral protection devices during the procedure.

When is interventional therapy suitable for carotid stenosis/occlusion?

Indications include:

• Symptomatic stenosis ≥50%;
• Asymptomatic stenosis ≥70%;
• Post-surgical restenosis;
• High surgical risk or inoperable lesions;
• Non-atherosclerotic stenosis (e.g., fibromuscular dysplasia);
• Carotid dissection;
• Severe stenosis with pseudoaneurysm;
• Short-segment (<10 mm) occlusion <6 months without distal thrombus;
• External carotid stenosis with internal carotid occlusion.

When is interventional therapy unsuitable?

Contraindications include:

• Symptomatic stenosis with intracranial vascular malformations;
• Acute/subacute cerebral infarction;
• Chronic total occlusion >6 months or >10 mm;
• Occlusion with unclear distal vasculature;
• Stenosis extending intracranially;
• Severely tortuous anatomy preventing safe device passage.

What are the risks of interventional therapy?

Risks include:

• Plaque dislodgment or dissection, potentially causing stroke or death;
• Cardiovascular complications, arterial spasm, embolism, hyperperfusion, stent thrombosis, occlusion, perforation, or restenosis.

How to treat unilateral stenosis with contralateral occlusion?

For patients with one-sided stenosis and contralateral occlusion:

• Treat only the stenotic side via endarterectomy or stenting to ensure cerebral blood flow;
• Occluded arteries are typically not reopened;
• Revascularization may improve neurological deficits but remains high-risk and exploratory.

DIET & LIFESTYLE

What should patients with carotid artery stenosis pay attention to after interventional surgery?

• Regardless of the treatment method, postoperative antiplatelet therapy (such as aspirin, Plavix, etc.) is necessary to effectively prevent restenosis and stroke;

• Continue treating hypertension, hyperlipidemia, and controlling blood sugar, and quit smoking;

• Guide patients to adopt a low-fat, light, and easily digestible diet, and maintain regular bowel movements;

• Attend regular follow-ups. If discomfort such as dizziness, headache, or visual disturbances occurs, seek medical attention promptly. The use of the above medications should be carried out under the guidance of a specialist.

PREVENTION

How to Prevent Carotid Artery Stenosis?

Generally, the prevention methods for carotid artery stenosis are similar to those for atherosclerosis.

• Balanced diet: Control total calorie intake to prevent obesity;

• Moderate physical activity: Beneficial for preventing obesity, improving circulatory function, and regulating lipid metabolism;

• Proper work-life balance: Maintain a regular routine, stay optimistic and cheerful, avoid overexertion and emotional agitation, balance work and rest, and ensure adequate sleep;

• Avoid smoking and excessive alcohol consumption;

• Actively manage risk factors related to the condition: Including hypertension, diabetes, hyperlipidemia, obesity, etc.;

• Regular check-ups: Be highly alert if symptoms of cerebral ischemia appear, such as tinnitus, blurred vision, dizziness, headaches, memory loss, vertigo, or excessive dreaming; seek medical attention promptly if carotid artery stenosis is detected during a check-up.