Carotid artery disease occurs when the major arteries in your neck become narrowed or blocked. These arteries, called the carotid arteries, supply your brain with blood. The two carotid arteries, one on each side of the neck, are the main blood supply to the brain. Each carotid artery extends upward from the aorta in the chest and into the base of the skull to enter the brain. Approximately 25 percent of strokes are caused by carotid artery disease from atherosclerosis, a buildup of plaque in the arteries that carry blood to the brain.  Eventually, the artery narrows, blood flow is decreased, and the risk of stroke is increased. The patient may experience symptoms such as blurred vision, slurred speech, or weakness, which are all signs of stroke. By removing the fat and cholesterol build-up inside the artery, adequate blood flow is restored, which can help prevent a stroke. Blockages of carotid arteries in the neck are responsible for more than half of all strokes.

As people age, arterial plaque made up of cholesterol, other lipids, calcium, and fibrous tissue can build up in the walls of their arteries. As the plaque deposits enlarge, the arteries become narrow and stiffened, a process known as atherosclerosis, or hardening of the arteries. When enough plaque has accumulated to interfere with blood flow in the main arteries to the brain, a person is said to have severe carotid artery disease. Eventually the narrowing can become severe enough to interfere with blood flow and a complete blockage that stops all blood flow through the carotid artery can follow.

The atherosclerosis disease begins with partial but progressive blockage or narrowing of arteries and tends to develop later in life. Fewer than 1 percent of adults in their 50s have significant narrowing of their carotid arteries. But 10 percent of adults in their 80s have extensive narrowing. Patients are at increased risk for developing carotid artery disease and stroke if they have a general tendency to have atherosclerosis, commonly in the form of coronary artery disease, or have a family history of heart disease or stroke.

Factors that put people at greater risk for carotid artery disease include:

• Smoking;             
• High blood pressure;             
• Diabetes mellitus; and             
• Family history of atherosclerosis.

What are the symptoms?

Carotid artery disease may not cause symptoms in its early stages. Unfortunately, the first sign of carotid artery disease could be a stroke. However, you may experience warning symptoms of a stroke called transient ischemic attacks, or TIAs. Symptoms of a TIA usually last for a few minutes to 1 hour and include:

These symptoms usually go away completely within 24 hours. However, you should not ignore them. Having a TIA means that you are at serious risk of a stroke in the near future. You should report TIA symptoms to your physician immediately.

If you experience the above symptoms for longer than a few hours, or they don't resolve within 24 hours, a stroke has probably occurred. You should contact your physician immediately.

Treatment

Once carotid artery disease has been diagnosed, the goal is to reduce the risk of a stroke. A stroke can occur if the carotid artery becomes blocked, a piece of plaque breaks off and travels to smaller arteries of the brain, or a clot forms and blocks a narrowed artery. Ultimately, a stroke occurs when brain cells are deprived of the oxygen and glucose carried to them by blood To prevent the disease from getting worse, doctors unblock the arteries to  restore adequate blood flow through the carotid artery. There are two techniques for doing this, carotid artery stenting and carotid endarterectomy.

Carotid artery stenting is an endovascular technique used to re-open blocked carotid arteries and prevent stroke. Because carotid stenting is minimally invasive, it provides an excellent treatment option to patients who are high-risk candidates for endarterectomy surgery. The procedure requires only a local anesthetic and a tiny puncture into an artery in the groin area, rather than opening the artery in the neck. The blockage is treated with balloon angioplasty and the placement of a stent - a small, self-expanding metal tube or 'scaffold' that keeps the vessel open, thereby preventing a stroke from occurring. A tiny umbrella-like filter is used to catch and remove loose pieces of plaque that develop during the stenting procedure before they travel to the brain and create a stroke.

X-ray studies using special dyes, called carotid angiograms, can show the degree of blockage of the carotid arteries. Other tests such as ultrasound and magnetic resonance angiography (MRA) can visualize blockages in the carotid arteries.

Prior to carotid stenting, blockages in the carotid artery were treated with a surgical procedure called carotid endarterectomy, in which surgeons made an incision in the neck artery to remove the plaque and diseased artery.

Carotid artery stenting is the only FDA approved system currently available for the prevention of stroke for patients who are at high risk for carotid endarterectomy. Patients who receive a carotid stent usually leave the hospital one or two days after the procedure.