In recent years it has become obvious that many strokes are caused by plaque in the carotid artery-the main artery supplying blood to the brain. There are two carotid arteries. They are located in the front of the neck with one carotid artery on each side.

Of the 500,000 strokes that occur each year in the US, it is estimated that 30-40% are caused by plaque in the carotid artery. This means that if the carotid artery plaque is discovered before a stroke occurs, the potential exists to prevent as many as 200,000 strokes annually.

Carotid artery plaque which causes stenosis of the artery is best diagnosed by ultrasound. The accuracy of the test is very dependent upon the technologist who is performing it however. The laboratory should be certified by ICAVL and ideally, the technologist and laboratory director should be Registered Vascular Technologists (RVT).

Plaque with Symptoms:

Plaque accumulation in the carotid artery can be associated with symptoms or it may be silent or "asymptomatic". Stroke may occur when a piece of plaque breaks free and travels to the brain or if the plaque in the carotid artery becomes so thick that it shuts down blood flow completely. Approximately 50% of people who suffer a stroke will die acutely and about 50% of survivors have some permanent neurological deficit such as paralysis or inability to speak.

Another symptom that can occur due to plaque in the carotid arteries is a Transient Ischemic Attack (TIA). This is sometimes called a "mini stroke" but actually it is not a stroke. TIA occurs when a piece of plaque or blood clot on the surface of the plaque breaks free and travels to the brain but then dissolves and does not cause actual death of brain tissue (a "stroke").

The symptoms of a TIA may include:

Temporary weakness or numbness of an arm or leg (or both, on the same side of the body)

Temporary speech difficulty
Transient loss of vision in one eye (called transient monocular blindness or TMB)

When a person who has experienced a TIA is found on ultrasound exam to have a critical stenosis of the carotid artery, the risk of a stroke is thought to be about 30% during the next six months after the occurrence of the TIA. Surgery is recognized as the best option in such patients according to a national prospective randomized study of this subject called the NASCET Trial.

Plaque without Symptoms:

Stenosis of the carotid artery is frequently silent and the plaque accumulation is discovered only because a patient's physician has recommended an ultrasound examination of the neck as a "screening procedure". Patients who should be screened for carotid plaque are those with:

High cholesterol
Coronary artery disease
Diabetes
Hypertension
Peripheral vascular disease
Family history of stroke

When plaque accumulation in the carotid artery has narrowed the artery by more than 75%, many vascular specialists will recommend that the plaque be removed. The advisability of surgery for this group of patients was proven by another prospective, randomized, national study called the ACAS Study. The safest and most effective method for dealing with carotid artery plaque is by an operation called a carotid endarterectomy.

The decision to recommend surgery for any individual patient must be considered on a case by case basis by the physicians and surgeon who are treating that individual patient.

Carotid Endarterectomy:

This operation is performed via a small incision on the neck. The artery is opened and the plaque is removed. Frequently, the vascular surgeon will enlarge the artery by sewing a patch of vein or artificial material onto the artery after the plaque is removed. The operation is safe, extremely effective in preventing stroke and quite durable. In a series of over 600 carotid endarterectomy operations performed by Dr Todd in New York , the risk of the operation was about 1% meaning that 99% of patients had no complications of the procedure.

The success of this operation has been shown to be very dependent upon the experience of the surgeon. Results of operation vary from complication rates (meaning stroke during the operation itself) of 1-2% to as high as 10% with high volume surgeons having lower stroke rates than surgeons with a low volume of carotid surgery. Nevertheless, a study of carotid surgery in New York State as an example showed that only a small minority of surgeons performed carotid surgery more than 30 times each year.

The average patient undergoing carotid endarterectomy is able to leave the hospital in one or two days. Recovery at home is rapid and the patient rarely has significant pain.

Recurrence rates of carotid stenosis are very low-particularly if a vein patch is used to enlarge the carotid artery after the plaque is removed.

Questions to ask the surgeon regarding Carotid Endarterectomy

Results of Carotid Artery Surgery

Carotid Artery Balloon Angioplasty and Stenting

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