Internal Carotid Artery Stenosis
Disease Description
The internal carotid arteries are located in the neck and are the main vessels supplying blood to the brain. Thickening of the arterial wall due to atherosclerosis results in the formation of plaques. Progressive plaque growth leads to gradual narrowing of the vessel — known as internal carotid artery stenosis.
Causes of the Disease
Atherosclerosis affects the entire arterial system and has a complex nature, largely based on genetic predisposition to impaired cholesterol metabolism and its deposition in vessel walls. The arteries most commonly affected are those supplying the heart, lower extremities, and the carotid arteries.
When the degree of internal carotid artery stenosis exceeds 70%, blood flow disturbances develop at the site of the plaque. These changes can damage the inner lining of the artery and lead to the formation of microthrombi that migrate with the bloodstream to the brain.
Such processes cause acute cerebrovascular events, known as ischemic stroke. Approximately 3% of people over the age of 65 have carotid artery atherosclerosis. While the disease has a hereditary component, several risk factors significantly increase its likelihood:
- Smoking
- High blood pressure
- Elevated blood cholesterol levels
- Diabetes mellitus
- Coronary artery disease or previous myocardial infarction
- Atherosclerosis of the lower limb arteries
- Increased total cholesterol, LDL and VLDL levels, and a high atherogenic index
Symptoms
Most individuals with carotid artery disease — even those with severe stenosis — experience no symptoms. Plaques are often discovered during routine examinations by a cardiologist or ophthalmologist, or after an ischemic stroke has occurred.
In rare cases, carotid artery stenosis may present with persistent tinnitus or fainting episodes. Most often, the first clinical manifestation of carotid artery disease is a stroke or a transient ischemic attack (TIA).
Key warning signs of an impending major stroke include TIAs, which may involve temporary paralysis of the arms and/or legs (lasting from minutes to several hours), speech disturbances, sudden or transient blindness in one eye, memory impairment, dizziness, or fainting.
Diagnosis
Triplex ultrasound scanning of the brachiocephalic arteries allows real-time assessment of the degree of narrowing, plaque size and structure, plaque stability, and measurement of blood flow velocity in the affected artery.
Multislice computed tomography angiography (CT angiography) provides three-dimensional imaging of the head and neck vessels with a diameter greater than 2 mm.
Conventional angiography is an invasive diagnostic method used when there is discrepancy between ultrasound and CT findings or prior to surgical intervention.
Treatment
Treatment of carotid artery atherosclerosis focuses on eliminating or controlling risk factors:
- Smoking cessation
- Optimal medical therapy aimed at preventing thrombosis, lowering cholesterol levels, and normalizing blood pressure
When carotid artery narrowing exceeds 70%, carotid endarterectomy (surgical removal of the plaque) or carotid artery stenting may be required to prevent stroke.
The choice of surgical treatment is based on comprehensive patient evaluation and depends on multiple factors. Decisions are guided by statistical evidence and recommendations from national and international professional societies, with the primary goal of maximizing patient safety and treatment effectiveness.
Treatment Prognosis
In patients with internal carotid artery stenosis of less than 70%, appropriately selected medical therapy keeps the risk of ischemic stroke low for an extended period. In most cases, regular follow-up and management of associated atherosclerotic conditions (such as coronary artery disease) are sufficient.
In patients whose carotid artery disease has already resulted in stroke, surgical intervention reduces the risk of recurrent cerebrovascular events by threefold. Preventive surgery in asymptomatic patients is justified when stenosis exceeds 70%, with the goal of significantly lowering future stroke risk.