A transient ischaemic attack (TIA) or "mini stroke" is caused by a temporary disruption in the blood supply to part of the brain.
The disruption in blood supply results in a lack of oxygen to the brain. This can cause symptoms similar to those of a stroke, such as speech and visual disturbance and numbness or weakness in the arms and legs.
However, a TIA does not last as long as a stroke. The effects only last for a few minutes and are usually fully resolved within 24 hours.
The main signs and symptoms of a TIA can be identified by remembering the word F.A.S.T., which stands for Face-Arms-Speech-Time.
- Face – the face may have fallen on one side, the person may be unable to smile, or their mouth or eye may have dropped
- Arms – the person may not be able to raise both their arms and keep them there due to weakness or numbness in their arms
- Speech – the person may have slurred speech
- Time – if any of these signs or symptoms are present, it is time to dial 999 immediately
If the above signs and symptoms last longer than 24 hours, it is regarded as a full stroke.
It is important that a person who has a TIA is checked and treated as soon as possible to minimise the risk of having a further TIA or a full stroke. With treatment, the risk of a further TIA or full stroke can be greatly reduced.
Read more about how to recognise the signs and symptoms of a TIA.
What causes a TIA?
During a TIA, one of the small blood vessels that supply your brain with oxygen-rich blood becomes blocked.
Atherosclerosis is a common cause of narrowed arteries. It occurs when fatty deposits, known as plaques, develop on the inner lining of your blood vessels. This can cause your blood vessels to become thickened, hard and less elastic, making it more difficult for blood to flow through them.
A TIA can also occur as a result of a blood clot that forms in a blood vessel and blocks the blood supply to your brain.
In rare cases, a TIA can be caused by a small amount of bleeding in the brain, known as a haemorrhage.
Read more about the causes of TIA.
Diagnosing a TIA
As TIAs are often over quickly, you may not have any symptoms by the time you see a healthcare professional.
You will be asked in detail about the symptoms you experienced during the TIA. For example, how long they lasted and how they affected you. This will help rule out other conditions.
If a TIA is suspected, you should be referred within seven days of the TIA to a specialist for tests.
Read more about diagnosing a TIA.
Treating a TIA
Following a TIA, you will need treatment to help prevent another TIA or a full stroke.
Your treatment will depend on your individual circumstances, such as your age and medical history.Your healthcare team will discuss the treatment options with you, and tell you about possible benefits and risks.
You may be given medication or asked to make changes to your lifestyle (see the prevention advice below). In some cases, surgery may be needed.
Read more about how TIAs are treated.
Preventing a TIA
TIAs often occur without warning. If you have a TIA, it is a sign another one may follow and further TIAs can have more serious effects or develop into a full, life-threatening stroke.
Regardless of whether or not you have had a TIA or stroke in the past, there are a number of ways you can lower your risk of having either in the future. These include:
Read more about how lifestyle factors can help prevent a TIA.