The carotid arteries are major blood vessels that lie deep in the neck on both sides of the windpipe. They carry blood from the heart to the brain and other parts of the head.
Normal carotid arteries are smooth inside but as people age the carotid arteries can become diseased due to build up of a fatty substance called plaque. This process is called atherosclerosis or “hardening of the arteries”. The narrowing caused by plaque is called a stenosis.
Plaque can severely obstruct blood flow in the arteries. In carotid arteries that require surgical removal of plaque, the blood flow is often reduced by two-thirds. In severe cases, blood flow can be reduced to a trickle. Ulcers can form on the surface of the plaque. Small blood clots can form on the ulcers. These clots and small particles of plaque can dislodge and travel up into the brain, causing a stroke.
A stroke occurs when blood stops flowing to a part of the brain due to a blockage in an artery. When interruption of blood flow is severe and lasts for more than a few minutes, brain cells will die. Disabling stroke occurs when larger areas of brain are deprived of blood flow. If a less important region of the brain is affected, the stroke will be less disabling. A stroke that affects an important part of the brain can be life threatening.
In some patients, surgical treatment to remove the plaque may be effective in reducing the risk of stroke. The surgical options are:
- carotid endarterectomy
- carotid angioplasty with stent
Although large clinical studies have confirmed that carotid endarterectomy and angioplasty with stenting have significant benefits in well selected patients, the procedure does have risks.