Live Life Team
There are arteries called carotid arteries which supply blood to brain. We have two of them, one on either side of the body. These arteries are prone to develop narrowing. Blood clots may form in these narrowed regions. If a blood clot dislodges and enters the blood stream, it may block a brain artery, cause a mini stroke or transient ischaemic attacks. Operating on these narrowing before it could cause a stroke is known as carotid endarterectomy.
Arteries are basically smooth, elastic vessels. As we get older, fat material, calcium, or fibrous tissue that travels in the blood accumulate within the artery walls, also known as atherosclerotic plaque. This makes the artery narrower, less flexible, and thicker. Aging, hypertension, diabetes, smoking, fatty diet also contribute to this plaque build-up. When this plaque hardens in carotid arteries, it is called carotid artery disease.
Carotid artery disease causes stroke in two ways:
Narrowing of artery becomes so severe, it blocks the artery completely, thus blocking blood supply to the brain, which causes a stroke. This is a haemodynamic stroke.
Blood clot that is formed on the rough surface of narrowing breaks off into the blood and causes brain arteries to be blocked. This is known as an embolic stroke, severity of stroke largely based on the size of the clot and the artery affected.
DIAGNOSIS
Some of the ways to know if the carotid arteries have become narrow:
Ultrasound.
MR angiography.
CT angiography.
These will help detect any narrowing and the extent of the narrowing and graded accordingly. These will help determine the extent of stenosis.
Mild stenosis. A little narrowing is present.
Moderate stenosis. Approximately 50-69% of the artery is narrowed.
Severe stenosis. Approximately 70% of the artery is narrowed.
Complete blockage. No blood flow in the artery.
The Operation
Carotid endarterectomy is done either under local or general anaesthesia. After the initial sterilizing process, an incision is made in the front of the neck so the artery can be visualized. These arteries are clamped to prevent blood flow. Based on the narrowing, decision on whether to place a tube in the artery or not is taken.
The artery is then opened up, the narrowing removed and a patch from the vein in the leg or of plastic material sewn back in place to prevent further narrowing. Then, the surgeon makes sure there is no more bleeding and then closes the wound. Some surgeons leave a small tube in wound to drain any blood that collects in neck after surgery. The tube is removed the day after surgery. The time taken for the entire surgery is one to two hours.
There might be certain degree of a risk of stroke associated with carotid endarterectomy. The surgeon will be able to discuss with the patient the amount of risk associated depending on the case. Complications like bleeding in the neck may occur; however, mostly this is treatable. A few patients (about less than 5 in 100), however get the clot removed surgically.
