Carotid Artery Disease

The carotid arteries are the two major arteries in the neck, located on either side of the windpipe, that provide most of the blood supply to the brain. Over time, these arteries may become narrowed or blocked due to a process called atherosclerosis or "hardening of the arteries". The buildup may obstruct the blood flow to the brain, leading to a stroke or a "mini" stroke (TIA).

Carotid artery disease is the cause of more than half of all strokes. Stroke, in turn, is the third highest cause of death and the leading cause of disability in the United States.

Why carotid stenosis occurs in some people but not others is unknown. However, certain risk factors, such as family history, high blood pressure, high cholesterol, heart disease, diabetes, smoking, and obesity, predispose some people to the condition.

How is Carotid Artery Disease Diagnosed?

In some cases, the first symptoms of carotid artery disease may be a stroke or a mini stroke called Transient Ischemic Attack (TIA). Symptoms of a stroke or TIA may include:

  • Numbness in the arms or legs, especially when limited to one side of the body
  • drooping of one side of the face
  • confusion
  • difficulty speaking or understanding speech
  • a sudden episode of memory loss
  • difficulty seeing from either one or both eyes
  • disorientation or disturbance in coordination
  • severe headache

The temporary presence of these symptoms (a few minutes or hours) indicates a 'mini' stroke (TIA). Symptoms lasting over 24 hours indicate more permanent damage due to a stroke.

Blockage (stenosis) of the carotid arteries can also occur without any signs or symptoms. This is called asymptomatic stenosis and it predisposes the patient to having a stroke. Asymptomatic stenosis in the carotid arteries is sometimes discovered during a routine examination, when a "bruit," a swishing sound, is heard through a stethoscope placed on the neck in the area over the artery. A bruit generally indicates a significant level of stenosis in the artery.

When your doctor suspects that you have a significant degree of stenosis in your carotid arteries, she or he will conduct an examination consisting of specific tests. These may include:

  • Duplex ultrasound
  • Cerebral angiogram
  • Magnetic Resonance Angiogram (MRA)
  • CT scan

How is Carotid Artery Disease Treated?

Mild carotid artery disease can sometimes be treated with medication and risk factor modification such as smoking cessation and reduction of cholesterol levels, and monitored for progression to a more severe form.

More severe disease is usually treated with an operation called carotid endarterectomy. In certain individuals a minimally invasive procedure called carotid stenting may be possible.

Open Surgery

Carotid Endarterectomy

Carotid endarterectomy is a surgical procedure for removing plaque from the carotid arteries to allow an unobstructed flow of blood to the brain. It is indicated in more severe cases of carotid artery disease.

The surgery takes approximately 1.5 to 2 hours. The surgeon first makes a small incision on the side of the neck to expose the artery. The affected area of the artery is clamped so that the surgeon does not disturb blood flow; sometimes a shunt is used to divert blood that generally flows down this pathway. The artery is then opened, and a special instrument is used to remove plaque from the inside of it. The artery is then sutured closed. In some cases, the surgeon may widen that area of the artery with a synthetic graft. Under normal circumstances, the procedure requires only an overnight stay in the hospital.

Some patients may be too ill or unable to tolerate the surgery, and a less invasive procedure called carotid stenting may be indicated instead.

Minimally Invasive Procedures

Carotid Stenting

A stent is a small, metal mesh tube that, once placed within the blocked artery, acts as a scaffold to keep the artery open. The placement of the stent into the carotid artery is accomplished with the use of a very thin tube called a catheter. The end of this catheter contains a deflated balloon onto which the unexpanded stent has been "loaded." This balloon tipped catheter is inserted, using local anesthesia, into a blood vessel in the groin via a needle puncture. The catheter is then guided up through the vascular system until its tip reaches the blocked point in the carotid artery. No surgical incision is required. Once the stent is positioned within the blocked portion of the artery, the balloon is inflated, expanding the stent in the area. The catheter is removed and the stent remains inside the artery permanently in order to help hold the artery open.

Because the stent is placed into the carotid artery via a catheter, this technique does not require surgery and is considered a significantly less invasive procedure than is carotid endarterectomy. However, because the efficacy and long-term outcome of this procedure have not been fully evaluated, it is currently used mainly in patients who are not optimal candidates for carotid endarterectomy and/or who are participating in a clinical trial.