Carotid Artery Disease and Stroke

Vascular

About Carotid Artery Disease and Stroke

The carotid arteries provide the brain with most of its blood supply and are located in the neck on either side of the windpipe. Carotid artery disease develops when one or both of these arteries become narrowed, or occluded, by an accumulation of a fatty substance called plaque. The build-up of plaque inside the artery walls is due to a process called atherosclerosis or "hardening of the arteries," and the resulting narrowing is called a stenosis. If plaque builds up to the point that it obstructs blood flow to the brain or particles of the plaque break off and travel to the arteries within the brain, a person can develop a stroke or a "mini" stroke (TIA). Carotid artery disease is the cause of more than one third of all strokes. Stroke, in turn, is the third highest cause of death and the leading cause of disability in the United States.

Risk Factors and Symptoms for Carotid Artery Disease and Stroke

Risk factors for carotid artery disease and stroke include smoking – the number one risk factor for all cardiovascular diseases – high blood pressure, high cholesterol, heart disease, diabetes, obesity, and a family history of cardiovascular diseases.

In some cases, the first sign of carotid artery disease could be a stroke. However, one may experience warning symptoms of a stroke called transient ischemic attacks (TIA) or mini-stroke. Symptoms of a TIA usually last for a few minutes to 1 hour and include:

numbness in the arms or legs, especially on just 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

These symptoms usually go away completely within 24 hours. However, they should not be ignored. Having a TIA could mean one is at serious risk of a stroke in the near future. TIA symptoms should be reported to a physician immediately.

If the above symptoms last longer than a few hours, or they don't resolve within 24 hours, a stroke has probably occurred. Contact a physician immediately.

Blockage (stenosis) of the carotid arteries can also occur without any signs or symptoms. This is called asymptomatic stenosis and it 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 examine you and conduct tests including:

Duplex ultrasound
Cerebral angiogram
Magnetic Resonance Angiogram (MRA)
Computed Tomography Angiogram (CTA)

Treatment for Carotid Artery Disease and Stroke

Medical Therapy

Patients whose blockages are mild to moderate can often manage their disease by making lifestyle changes such as quitting smoking and by working with their doctors to take care of related conditions such as diabetes, high blood pressure, and high cholesterol. Doctors will monitor the disease and initiate other treatments if the disease begins to progress. They may also prescribe blood-thinning drugs or other medications.

Minimally Invasive Procedure

Carotid Stenting: In some cases doctors may place a stent, a small mesh support tube, at the site of the blockage in the carotid artery. The procedure is performed under local anesthesia. The stent is inserted via a small incision in the femoral artery in the groin and threaded through the blood vessels to the area of blockage. Once the catheter reaches the blockage, surgeons expand the stent by inflating a balloon. The stent is left permanently in the artery to provide a reinforced channel through which blood can flow. Patients usually go home the following day.

The effectiveness of carotid stenting, and the long-term outcomes of those who undergo the procedure, are still being evaluated. Stents are currently used mainly in patients who are not optimal candidates for carotid endarterectomy and/or who are participating in a clinical trial (research study).

MERCI Retriever: The MERCI Retriever is a tiny corkscrew-like device that is threaded through the circulatory system through a puncture of the artery of the leg and guided to the arteries of the brain to ensnare and remove a clot. At the clot, the Retriever is then deployed from inside the catheter and slowly rotated to ensnare the clot as a corkscrew would ensnare a cork. The MERCI Retriever, with the clot attached, is then retracted into the catheter, and the entire apparatus is withdrawn from the body. Pulling out the clot reopens the blood vessel and re-establishes blood flow into the brain.

Traditional Surgery

Carotid Endarterectomy: The standard method of treating disease in the carotid artery is via an operation called carotid endarterectomy. During this procedure, which is performed under general anesthesia, surgeons clamp one of the diseased carotid arteries to stop blood from flowing through it, make an incision into the blocked section of the artery, and remove the plaque deposit. The surgeon may also widen the artery using a patch from a vein in the leg or a synthetic material. The artery is then sewn closed and unclamped. Patients usually go home the following day.