More information on TIA and stroke prevention


What is a transient ischaemic attack?


Transient ischaemic attacks (TIAs for short) are a kind of mini-stroke. The symptoms may be very like a stroke but they get better within 24 hours. Common symptoms include brief attacks of weakness, clumsiness, numbness or pins and needles of 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 for a few minutes or hours and are usually better within a day.


2. What causes TIAs?


TIAs and strokes can be caused by atherosclerosis (hardening of the arteries), which involves formation of fatty deposits in the wall of the carotid artery in your neck. This may be caused by smoking, high blood pressure, high cholesterol levels and poorly controlled diabetes; it interferes with the blood flow up to your brain. Small pieces of these deposits may break away, travelling in the blood flow towards your brain, where they may block a smaller artery and hence starve the surrounding brain tissue of blood. Alternatively, the rough surface of the fatty deposit may lead to formation of a blood clot which can also break up and have the same effect. The symptoms you experience depend on which blood vessel to the brain or eye is blocked.


In TIAs the blockage is temporary and quickly clears itself.


3. Are there any other causes?


There are several illnesses which may seem very much like TIAs. These include migraine, epileptic fits or seizures, low blood sugar, fainting and changes in heart rhythm. TIAs do not usually cause ‘blackouts’, fainting or loss of consciousness. These other symptoms need different treatments and it is important that people with TIA - like symptoms are seen by a specialist to find out the cause of the trouble.


4. Why are TIAs important?


Although TIAs may be frightening they do not cause 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 TIAs 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 that your symptoms are a cause for concern, then a series of tests will be arranged. A painless ultrasound scan of your neck will check for atherosclerosis in your carotid artery. Other tests may include blood tests to detect high cholesterol or diabetes, and an ECG (heart tracing). Further tests, such as an echocardiogram (scan of your heart) and/or a brain scan may be organised.


6. What about treatment?


Your treatment depends on the results of your examination and tests. If you smoke, you should stop completely – advice and support is available. High blood pressure, high cholesterol or sugar levels in the blood can often be helped by a healthier diet, although drugs may also be needed. Aspirin may be prescribed to make your 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. Clopidogrel is a drug like Aspirin, which also reduces the stickiness of your blood. Your specialist may prescribe a combination of both Aspirin and Clopidogrel.


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 your operation including an angiogram (an xray of your carotid artery) and a CT scan of your brain. More information about these procedures is available - please ask your specialist.