Carotid artery disease occurs when the major arteries in the neck—called the carotid arteries—become narrowed or blocked, usually due to atherosclerosis, the buildup of fatty deposits (plaque) on the artery walls. These arteries are responsible for supplying oxygen-rich blood to the brain, and their narrowing significantly increases the risk of stroke or transient ischemic attack (TIA).

In the early stages, carotid artery disease is often silent and without symptoms. It may first be detected as a bruit, an abnormal sound heard over the artery with a stethoscope. As the disease progresses, small clots or plaque fragments can break off and travel to the brain, leading to stroke symptoms, such as sudden weakness, difficulty speaking, or vision problems.

Risk factors include high blood pressure, high cholesterol, diabetes, smoking, and a family history of vascular disease. Diagnosis is commonly made using carotid Doppler ultrasound, and may be further assessed with CT angiography (CTA) or MR angiography (MRA) to evaluate the degree of narrowing.

Treatment depends on the severity of the stenosis and presence of symptoms. Mild to moderate cases may be managed with medications and lifestyle changes, while severe narrowing or symptomatic disease may require intervention through carotid endarterectomy (surgical plaque removal) or carotid artery stenting.