1. What is a Transient Ischaemic Attack?
Transient Ischaemic Attacks (TIA’s for short), are a kind of mini-stroke. The symptoms may be very like a stroke but they get better very quickly. Common symptoms include brief attacks of weakness, clumsiness, numbness or pins and needles in the face, arm or leg on one side of the body. Temporary slurring of speech or difficulty in finding words can also occur. The eye can also be affected resulting in loss of vision in one eye. This is called Amaurosis Fugax. These attacks may only last a few minutes or hours and are usually better within a day.
2. What causes TIA’s?
TIA’s and strokes are caused by narrowing and blockages of the blood vessels that supply the brain. The trouble is due to hardening of the arteries (atherosclerosis) which may be caused by smoking, high blood pressure, high cholesterol levels and diabetes. In TIA’s, the blockage is temporary and quickly clears itself. The symptoms depend on which blood vessel to the brain or eye is blocked and so which is starved of blood.
3. Are there any other causes?
There are several illnesses which may seem very much like TIA’s. These include migraine, epileptic fits or seizures, low blood sugar, fainting spells and changes in heart rhythm. TIA’s do not usually cause “blackouts”, fainting or loss of consciousness. These other illnesses need different treatments and it is important that people with TIA symptoms are seen by a specialist to find out the cause of the trouble.
4. Why are TIA’s important?
Although TIA’s may be frightening, they do not cause any permanent damage. However, a person who has had a TIA has a higher risk of suffering a stroke. The risk of having a stroke in the first year after a TIA is about 10% and about 5% each year after this. It is important that TIA’s are investigated so that any underlying cause can be corrected to try to prevent a stroke in the future.
5. What tests are required?
If your specialist thinks your symptoms are cause for concern, then a series of tests will be arranged. These usually include blood tests for high cholesterol and diabetes, and a heart tracing (ECG). Sometimes, TIA’s are due to the narrowing of a blood vessel in the neck (carotid artery). A painless ultrasound scan of the neck will check on this.
6. What about treatment?
Your treatment depends on the results of your examination and tests. If you smoke, you should stop completely. High blood pressure, high cholesterol or high sugar levels in the blood can often be helped by a healthier diet, although drugs may also be needed. Aspirin may also be prescribed to make the blood less sticky. This reduces the risk of having a stroke or heart attack by about 25%. The dose of aspirin is small and does not usually cause indigestion. If the ultrasound scan suggests that the carotid arteries in the neck are narrowed, then an operation to correct the narrowing may be necessary. This is called a carotid endarterectomy. Further tests may be arranged before the operation, including an x-ray of the arteries (arteriogram) and a scan of the brain (CT scan).
1. What is the problem?
Every day, many people have a stroke (“Cardiovascular Accident or CVA”) or warning signs of a stroke (“mini stroke” or “Transient Ischaemic Attack”). Such patients are at a higher risk of having another, perhaps major, stroke. All patients with an increased risk of stroke are given medical treatment and advice to reduce this risk. This includes treatment of high blood pressure, diabetes, high fat levels, heart disease and stopping smoking. In addition, aspirin is generally given. However, in many cases, surgical treatment is also recommended. In these cases, such as yourself, there is a narrowing of the artery in your neck that supplies blood to the brain. This trouble is due to hardening of the arteries (atherosclerosis). It is important to realise that the left side of the brain looks after the right arm and leg and the right side of the brain looks after the left arm and leg. For this reason, the patient often thinks that the “wrong” side is being operated upon when, in fact, it is the correct side! At present, we also know that the presence of a narrowing (stenosis) in your carotid artery makes the chances of suffering a stroke in the future much higher than in a person without such a narrowing. We also know that performing an operation, called carotid endarterectomy (to correct the narrowing), will actually reduce the chances of stroke and/or death significantly.
2. Before the operation
Surgery involves admission to hospital for about five days and will generally be carried out on the day after admission. Before the operation, you will be seen by the anaesthetist who will examine you, and by one of the surgical team who will explain anything that you are not sure about. Your nurse will also explain the ward routines and will answer any questions you may have. You will have a number of pre-operative tests including blood tests, a cardiogram and a chest x-ray. You will be asked to eat or drink absolutely nothing for 6 to 12 hours before the operation. If you feel unable to sleep, please ask the nurse or doctor to give you a sleeping tablet to allow you plenty of rest. About one hour before the operation, you will be given a sedative.
3. The operation
Once you have been anaesthetised, a cut is made in the skin of the neck over the carotid artery. The artery is then temporarily clamped off and the diseased lining (plaque) removed. The artery is then closed. Sometimes a patch of vein is used to prevent narrowing and this will be taken from the top of your leg through another small incision. Alternatively, an artificial patch may be used or the artery may simply be stitched up. Either metal staples or stitches will be used to close the skin and there may be a drainage tube placed which will be taken out after 24 or 48 hours.
4. After the operation
When you wake up, you will find that your arm is connected to one or two plastic tubes to provide you with fluids and to monitor your blood pressure. You will usually be returned to a high dependency unit (HDU) so that they can keep a special eye on you for 24 hours. After this, you will be returned to your own ward. You will be allowed to drink after you have woken up completely from the anaesthetic. The operation itself is not particularly painful although you may need some painkillers, which will be given to you, if required. In some cases, you may be able to give yourself medication and you will be shown how to do this. On the following day after surgery, you will be allowed to get out of bed and to eat normally. In many cases, you may be allowed home on the second or third post-operative day. Arrangements will be made to remove the skin staples or sutures, if they are not removed before you leave.
5. Are there any risks?
Some minor bruising around the wound is common after the operation. Sometimes a blood transfusion is necessary although this is uncommon. Bruising of the neck may take several weeks to settle down. There is likely to be a numb area on the side of the neck that may take several months to settle down. Occasionally, this numbness can be permanent. Temporary weakness of the side of the mouth or tongue is possible though it is only very rarely permanent. There is a small (but finite) risk of developing a stroke during the operation combined with a very small risk of death. The combined “operative” stroke and death risk is less than 5%. However, you are more likely to avoid a major stroke in the long run, if you undergo surgery. You may wish to discuss these risks with your surgeon in more detail before the operation.
6. What about afterwards?
You will usually receive an appointment to be seen in the outpatient clinic in about one month’s time. An ultrasound scan, similar to the one that was performed before your operation, may also be arranged to check the carotid artery is working properly. The operation usually gives good long-term relief. You can also help improve your general health by taking regular exercise, stopping smoking and reducing the amount of fat in your diet. All these things will help reduce the chances of further trouble from arterial disease.