What is Carotid artery disease?

The carotid arteries are the two major arteries, one on each side of the neck, that run from the aorta in the chest to the skull and supply the brain with oxygen and nutrients in the blood. With age and also due to life style choices like smoking, lack of exercise, and eating a diet with a high content of saturated fats and cholesterol, a build up can be deposited on the inside of the artery wall. This build up is called plaque and consists of cholesterol, calcium and fibrous tissue. It also contains white blood cells that cause an inflammation at the site of the plaque build up. Other risk factors for this condition are a family history of carotid artery disease, diabetes, obesity, and high blood pressure.

While only 1% of people between the age of 50 and 59 have a significant amount of plaque in their carotid arteries, 10% of people in the age group between 80 and 89 years suffer from this condition.

The plaque can become so big that it restricts the blood flow to the brain. This condition is called carotid artery disease. It can lead to strokes by at least to different mechanisms. First the irregular surface of the plaque and the inflammatory cells that are present in the plaque can make it look to the body’s defense systems like an injury that requires blood clotting to stop bleeding. Platelets called blood cells that usually form a clot in an open wound to stop bleeding can aggregate in the plaque and completely block the carotid artery, thus severely restricting or entirely stopping the blood flow to the brain. This is called a stroke.

There is another way in which carotid artery disease can cause stroke. This is actually the more common way: the plaque is a fragile structure and a small piece can easily break off from it at any time. This piece of dislodged plaque can be transported further up in the artery and block a smaller vessel inside the brain cutting of the circulation to this area.
Stenosis symptoms

Carotid artery disease often does not cause any symptoms, especially in its early stages. If your doctor suspects that you have carotid artery disease he or she might listen to the sounds of the blood flow in the carotid arteries by holding stethoscope to your neck. The plaque that causes carotid artery disease also makes the blood flow around it in a turbulent fashion, which produces a sound called carotid bruit. The physician can then order further tests like computer tomography (CT) scan, ultrasound, magnetic resonance imaging (MRI), or an angiography to confirm the presence and see the extend of the stenosis (clog or narrowing) in the carotid artery.

Sometimes the first sign of carotid artery disease is a stroke. However, some people whose blood flow to the brain is disturbed by the stenosis in their artery experience temporary symptoms of restricted blood flow to the brain. This condition is called a temporary ischemic attack (TIA). The symptoms can be very similar to the symptoms of a stroke, but last only a few minutes to an hour. They can be slurring of speech, loss of vision in one eye, weakness, numbness, or tingling on one side of the body, paralysis in an arm or leg, or on one side of the face.


Treatment


The treatment for carotid artery disease depends on the severity of the disease. In some cases life style changes like exercise, a healthy diet, quitting smoking and loosing weight together with medication to control diabetes, high blood pressure and lower blood cholesterol levels can be enough to prevent a progression of the disease in the early stages. Your physician might also prescribe medications that can prevent platelets from aggregating in the plague or that inhibit blood clotting.

In more advanced stages, especially if you experience symptoms of restricted blood flow to the brain, the removal of the clog might be necessary. There are basically two options available to do this. The first method is a surgery called carotid endarterectomy. During this surgery, the surgeon will open the carotid artery and remove the clot. The surgeon might also remove any diseased parts of the artery. At the end of the surgery the artery will be sewn together providing better blood supply to the brain. Risks of this procedure depend on your age, your overall health and on other factors like whether you have transient ischemic attack symptoms or whether you had a prior stroke.

In some cases the risks of this surgery might outweigh possible benefits. For these cases a newer procedure is approved by the FDA. This procedure is called angioplasty and stenting. It is a procedure that is widely used for the narrowing of the blood vessels that supply the heart with oxygen. This condition is known as coronary artery disease. However, as a treatment of carotid artery disease, it is a fairly new procedure and it is not yet know how well it prevents strokes, which is the reason why, right now, it is only used for patients that are considered to have a too high risk to undergo the more invasive carotid endarterectomy or for patients that have enrolled in a clinical trial to evaluate the effectiveness of this procedure.

During angioplasty and stenting, a small incision is made in the groin area and a catheter is introduced into artery in the groin. The catheter is then threaded to the narrowed area in the carotid artery. The physician will inject a special dye to make the narrowing visible on an x-ray. A small balloon on the tip off the catheter will be inflated in the narrowing to flatten the plague against the artery walls. A stent, which is a small metal mesh tube, will be inserted into the artery to keep it open. It will be left in the artery permanently to provide support and keep the blood vessel open.

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