What is carotid artery disease?

The brain survives on a continuous supply of oxygen and glucose carried to it by blood. The carotid arteries are the blood vessels that carry oxygen-rich blood to the head, brain and face. They are located on each side of the neck. Carotid artery disease is the narrowing or blockage of the carotid arteries (stenosis) due to plaque build-up (atherosclerosis). The plaque can then crack, and develop an irregular surface, which is when it begins to cause problems. If a piece of plaque or a blood clot breaks off from the wall of the carotid artery it can block the smaller arteries of the brain. When blood flow to the brain is blocked, the result can be a transient ischaemic attack (TIA) which temporarily affects brain function, or a stroke, which is permanent loss of brain function.

Common symptoms of TIA include brief attacks of weakness, clumsiness, numbness or pins and needles of the face, arm or leg on one side of the body. The eye can also be affected resulting in loss of vision in one eye and is called amaurosis fugax.

Carotid artery disease is one of the most common causes of stroke. More than half of the strokes occur because of carotid artery disease.

Will I need an operation?

If you have had a stroke, TIA or amaurosis fugax and you have evidence of carotid artery stenosis (>50%) you will be referred to a vascular surgeon for consideration for surgery. There is good evidence that in those patients with a narrowing greater than 70% of the diameter of the artery benefit from surgery.

All patients with carotid artery disease benefit from taking aspirin and a statin and managing risk factors such as smoking, blood pressure, cholesterol and diabetes.

The benefit of the aspirin is to reduce the stickiness of small blood cells called platelets which adhere to the irregular surface of the plaque, but can then break off as a small clump. Where aspirin is not appropriate, other anti-platelet drugs can be prescribed.

The benefit of a statin is partly in reducing the cholesterol, which was the initial reason for them being developed, but they also appear to reduce the tendency for atherosclerotic plaques to crack and so even patients with low cholesterol will benefit from taking them.