Vascular disease is as prevalent as both cancer and heart disease and accounts for 40% of deaths in the UK. This leads to over 200,000 deaths a year many of which are preventable.
What is Carotid Disease?
The carotid artery in the neck provides the principal blood supply to the brain. The artery (common carotid artery) runs up the side of the neck and divides into two branches just below the angle of the jaw. One branch supplies the face (external carotid artery). The other branch passes directly to the brain with no other branches in the neck (internal carotid artery). Diseased arteries tend to narrow where they divide. Narrowing at the carotid bifurcation (division of common carotid artery) may directly restrict the blood supply to the brain. Additionally and more importantly, debris stuck to the narrow area may break off into the bloodstream passing to the brain or into the artery to the eye.
How is carotid disease detected clinically?
Debris passing into the brain may produce a mini-stroke. A mini-stroke (transient ischaemic attack or TIA) is a small stroke which recovers within 24 hours. It can affect the face, arm or leg on one side of the body. Sometimes there is transient blindness affecting one eye usually lasting only a few seconds. Sometimes the speech centre in the brain is affected leading to either jumbled speech or complete loss of speech. A key feature of a TIA is that it recovers completely.
What tests can be used to detect carotid disease?
Ultrasound is the main way of diagnosing carotid disease. The ultrasound image may show narrowing on screen where the carotid bifurcation is usually easily seen. Ultrasound can also be used to study the speed of blood flow at the point of narrowing. A carotid angiogram is an X-ray of the circulation to the brain taken by injecting dye (contrast) into the carotid artery. A catheter is threaded into the artery from puncture of the femoral artery at groin level. This procedure is performed under local anaesthetic.
Who is at risk?
TIAs affect those of increasing age (usually over 60 years) and are more common in men than women. TIAs are much more common in smokers, patients with high blood pressure, diabetics and those with high cholesterol.
Do I need treatment?
The combination of a TIA and a tight narrowing of the carotid artery put you at risk of a major stroke. In some cases it may be worthwhile treating a narrowed carotid artery in the absence of symptoms although overall the risk of stroke is less in the absence of symptoms. If a procedure is recommended, it should be done as soon as possible after TIA symptoms, because this is the time of greatest risk for a major stroke. If treatment is delayed for whatever reason there is a significantly increased risk of major stroke during the following 12 months but particularly during the following 3 months.
What does treatment involve?
There are three lines of treatment; medication, stenting and surgery.
- Medication: all patients will be recommended to take an Aspirin-like drug.
- Carotid endarterectomy is a well established operation to unblock the narrowed carotid artery. The artery is carefully exposed through an incision running vertically in the side of the neck. The artery is opened, cleared of the debris and carefully sewn up again. The operation can be done under local or general anaesthetic.
- Carotid Stenting is a relatively new development. Here the narrowing in the artery is dilated by a balloon under X-ray control. A metal stent covers the balloon and this is pushed into the artery wall to hold the artery open. Trials of this treatment are underway to compare it with surgery and you may be asked to enter such a trial. If surgery is difficult (scarring form previous surgery or radiotherapy, large neck with poor mobility) stenting may be preferred to surgery.
Is treatment successful?
Carotid endarterectomy reduces the threat of stroke form about 1 in 5 to 1 in 25. It normally provides very good long-term results. The principal risk is that a small number of people (between 1 and 3 in 100) having the procedure will have a stroke during the operation. This stroke is often severe and may lead to loss of life. There are few side effects of the operation. Very occasionally, there may be damage to adjacent nerves. This may lead to a hoarse voice, some weakness of the side of the mouth or impaired tongue movements, which interfere slightly with speech.
Can I help myself?
You can help yourself by stopping smoking if you smoke. Regular exercise and attention to diet are beneficial. Your blood pressure, cholesterol and blood sugar should be checked, and if elevated, you should have medication to control them.