Carotid Artery Disease is a serious condition afflicting 1 percent of adults age 50 to 59, and 10 percent of adults age 80 to 89. It occurs when the major arteries in the neck become narrowed or blocked. These arteries supply blood to the brain. The carotid arteries extend from the aorta in the chest to the brain inside the skull.
Arteries are normally smooth and unobstructed on the inside, but with age, a sticky substance called plaque can build up in the walls of the arteries. Plaque is made up of cholesterol, calcium, and fibrous tissue. As more plaque builds up, the arteries narrow and stiffen. This process is called atherosclerosis , or hardening of the arteries.
Carotid artery disease occurs when enough plaque builds up to restrict blood flow through the carotid arteries. This is a serious condition that can lead to a stroke. Some plaque deposits are soft and are prone to cracking or forming roughened, irregular areas inside the artery. If this occurs, the body will respond by flooding the cracked and irregular areas with blood-clotting cells called platelets. A large blood clot may then form in the carotid artery or one of its branches. If the clot blocks the artery enough to slow or stop blood and oxygen flow to the brain, it could cause a stroke. More commonly, a piece of the plaque itself, or a clot, breaks off and travels through the bloodstream. This particle can then lodge in a smaller artery in the brain and cause a stroke.
Injury to the artery's inner lining can cause plaque build up. Factors that can injure artery walls include:
- High cholesterol
- High blood pressure
A family history of hardening of the arteries also may increase the chances of developing carotid artery disease.
- Quit smoking
- Exercise regularly
- Eat a healthy diet
- Maintain a healthy weight
- Control diabetes and high blood pressure
The first sign of carotid artery disease can be a stroke. However, warning symptoms of a stroke, called transient ischemic attacks (TIAs), or mini-strokes can be a tip off. Symptoms of a TIA can last for a few minutes or up to one hour. Call your physician immediately if you experience any of the following symptoms:
- Weakness, numbness, tingling sensation on one side of the body
- Inability to speak
- Loss of vision in one eye
One of the following tests may be ordered to diagnose carotid artery disease:
- Carotid Duplex Scan - this is a noninvasive ultrasound exam.
- CT Scan and CT Angiography (CTA) - CT scans show the area of the brain that has poor blood flow. A contrast dye may be injected to make blood vessels visible on the image. A CTA scan shows the arteries in the neck and head, identifying the areas of arterial narrowing.
- Magnetic Resonance Angiography (MRA) - MRA uses radio waves and magnetic fields to create detailed images which can show moving blood flow. Sometimes, a material called gadolinium is injected to make the arteries more visible and accurately diagnose carotid artery disease.
- Angiography - A contrast dye is injected through a catheter and threaded into the arteries prior to capturing x-ray images of the arteries. This test shows how well blood flows through the arteries and indicates if they have become narrow.
Surgery may be required if carotid artery disease becomes severe. Signs that the disease has progressed include TIA symptoms or narrowed carotid arteries. During surgery, plaque that is blocking the carotid artery is removed during a procedure called endarterectomy . This type of procedure can be performed using a local or general anesthetic. Once the anesthesia has taken effect, an incision is made in the neck and plaque in the inner lining of the carotid artery is removed. Patients generally leave the hospital the day after the procedure.
Angioplasty and Stenting
Angioplasty and stenting is a procedure usually performed using a local anesthetic. A long, thin tube called a catheter is inserted through a small puncture site over a groin artery. It is guided through the blood vessels to the carotid artery. An x-ray image, called an angiogram, is performed by injecting a contrast dye through the catheter to show the location of the plaque. Another catheter that carries a tiny balloon is then inserted. The balloon inflates and compresses the plaque against the walls of the artery. Following this procedure, a tiny metal-mesh tube, called a stent, is placed in the artery to hold it open. The hospital stay can be one to two days following this procedure.