Carotid artery disease refers to a narrowing within the carotid arteries (the arteries that supply blood and oxygen to the brain). It is usually caused by the buildup of plaque within the artery (atherosclerosis).
Blockages caused by atherosclerosis in the carotid arteries cause about 25 percent of preventable strokes. Stroke is the third leading cause of death in North America.
Risk factors for atherosclerosis include:
- High blood pressure
- High cholesterol
- Smoking cigarettes
In its early stages, carotid artery disease may not have any symptoms until you experience what’s commonly called a “mini-stroke” or transient ischemic attack (TIA). If your doctor suspects you have carotid artery disease, it can be easily diagnosed using ultrasound or other imaging technology.
Strokes occur when pieces of the diseased artery break off and travel into the brain, eventually blocking blood flow, causing part of the brain to die. This can either cause a full-blown stroke, resulting in permanent neurological problems in a minority of people, a or a transient ischemic attack (TIA), which produces the same symptoms as a stroke but resolves in less than a day, often in a matter of minutes.
Symptoms of both stroke and a transient ischemic attack (TIA) include:
- Weakness, numbness, or paralysis of a limb or one side of the body
- Inability to speak or articulate clearly
- Blindness or other visual changes in one or both eyes
- Sudden, severe headache
- Dizziness or difficulty walking
Along with atherosclerosis, there are other less common conditions that also can affect the carotid arteries, including:
- Aneurysms, or swelling of the artery
- Carotid artery dissections, where the wall of the artery splits
- Carotid body tumors, which are tumor that arises from and involves the carotid arteries
- Fibromuscular dysplasia, an inflammatory condition of the artery
- Inominate artery disease, or blockages in an artery below the carotid artery
- Recurrent blockages after prior carotid artery surgery
Mild to moderate blockages in the carotid artery are treated with medications called antiplatelet agents, such as aspirin, that block the formation of blood clots. In addition, treatment involves identifying and reducing risk factors, such as cigarette smoking and high blood pressure.
Ultrasound studies are repeated over time to monitor the blockage.
If your carotid artery disease progresses, you may need surgery. Carotid endarterectomy surgery is currently the best treatment for reducing the risk of stroke in patients with severe blockages in the carotid arteries.
Carotid artery endarterectomy involves:
- Opening the artery
- Removing the plaque that is causing the narrowing
- Closing the artery, usually with a synthetic patch
During surgery, a temporary bypass is often used to allow blood to flow around the area of surgery as it travels to the brain.
Not all patients are candidates for surgery, particularly those patients who are in overall poor health or have other health issues.
Other non-surgical options to treat blockages in the carotid arteries include balloon angioplasty and stents. Both of these procedures use a catheter-guided balloon, inflated in the blocked area, to open up the carotid artery. A metal stent may be inserted to help keep the artery expanded.
Currently, angioplasty and stents are recommended only for patients who aren’t candidates for conventional surgery because the risk of stroke during the procedures and the long-term results are still being studied.