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. Your carotid arteries extend from your aorta in your chest to the brain inside your skull.
Age is a significant risk factor for this condition. Only 1 percent of adults age 50 to 59 have significantly narrowed carotid arteries, but 10 percent of adults age 80 to 89 have this problem.
As you age, a sticky substance called plaque can build up in the walls of your arteries. As more plaque builds up, your arteries narrow and stiffen. This process is called atherosclerosis, or hardening of the arteries. The buildup of atherosclerosis in the carotid arteries is a serious health problem because it can cause a stroke.
Carotid artery plaque causes strokes because these diseased arteries are prone to forming blood clots within them, which can break off, and float directly into the brain. A piece of plaque can also break off and travel into the brain. There, the clot or plaque will lodge into a small blood vessel in the brain, obstructing the flow of blood to that area, and causing the death of that part of the brain. This is called a stroke, and it can have debilitating consequences.
Carotid artery disease may not cause symptoms until a patient has a debilitating or fatal stroke. However, we work hard to detect patients who have asymptomatic carotid stenosis, in order to prevent these terrible strokes from happening.
We know that carotid disease is caused by atherosclerosis. Therefore, patients with a history of significant atherosclerosis are often screened for carotid artery disease using an ultrasound. Many cases of carotid artery disease are discovered this way, before the disastrous outcome of stroke can occur. At our office, we screen all appropriate candidates for carotid disease, in order to catch the disease before it becomes dangerous.
However in other patients, the first sign of carotid artery disease may be something called a TIA (transient ischemic attack). TIAs are mini-strokes, and have symptoms similar to strokes. However, these symptoms usually go away within a few hours, and leave no residual effects. Symptoms from a TIA include:
- feeling weakness, numbness, or a tingling sensation on one side of your body, for example, in an arm or a leg
- being unable to control the movement of an arm or a leg
- losing vision in one eye (many people describe this sensation as a window shade coming down)
- being unable to speak clearly
These symptoms are very dangerous, because they often can lead to debilitating strokes. Patients with these symptoms are referred quickly to a vascular surgeon, and surgery is often done as soon as possible.
In patients who have already had strokes from their carotid artery disease, surgery is not always indicated. However, sometimes with milder strokes, surgery is done to prevent a more debilitating stroke down the line. Your surgeon will discuss these cases individually, presenting the risk/benefit analysis with you and your family.
Duplex ultrasonography is the most common test done to diagnose carotid disease. The ultrasound is a very good test for this condition because it is minimally invasive, and because it gives excellent information regarding the blood flow in the vessel and the extent of the narrowing. In many cases, the surgeon can operate based solely on the results of the ultrasound. However, in some cases, more information may be needed, and your surgeon may refer you for a CT, an MRI or even an angiogram of your carotid arteries in order to obtain more specific information.
Your treatment will depend on a few key issues: the severity of the plaque, the presence of symptoms from the disease, and your general health.
The first step in treating carotid disease is controlling some key health conditions which can exacerbate this condition. As a first step, we will work with you and your primary care doctor to control your blood pressure, your glucose levels if you have diabetes, and your cholesterol. Drugs such as plavix or aspirin are usually used in order to decrease the risk of clot formation. Cholesterol lowering drugs (statins) are often used as well, since these drugs can lower risks of complications from carotid artery disease.
Carotid Surgery (Carotid Endarterectomy)
For certain patients, surgery is required. Your surgeon will discuss your specific case in detail, but in general, surgery is performed if the vessel is severely narrowed, or if the you are having symptoms from the narrowed vessel, such as those discussed above.
Surgery for the carotid artery narrowing is called a "carotid endarterectomy." It involves taking out the plaque in the artery, and sewing the artery back up, often using a "patch" technique, which makes the artery slightly larger. After this procedure, the vessel is wide open, and there's a much lower risk of stroke. The surgery is performed through a small incision in the neck. It is in general very safe, and often patients are able to go home the very next day. However, because of the nature of the plaque in the carotid artery, there is a small risk of stroke with this surgery. However, the benefit of carotid endarterectomy in these patients outweighs the risk of strokes from the surgery.
Carotid stenting is a fairly new procedure for treating carotid disease. It is a minimally invasive procedure, where a puncture is made in the groin, and a long catheter is delivered to the artery in the neck using advanced x ray techniques (fluoroscopy). The narrowing of the artery is treated using a metal tube called a stent, which is placed in the narrowed vessel and expanded with a balloon. The balloon is then removed, and the stent is left in place.
Carotid stents are effective, but the procedure also carries with it a certain risk of stroke. Although this is an alternative to carotid surgery at this time, the results of this procedure are not as well studied, and for now, carotid stenting is reserved for certain patients only, such as patients who are extremely sick, or patients who have had previous neck surgery, making carotid endarterectomy more hazardous.
Ultimately, your doctor will be able to discuss this option with you at length, but It has been approved for symptomatic patients considered to be at high risk for the surgical endarterectomy procedure, or for patients who have agreed to participate in ongoing clinical studies designed to determine its effectiveness.