Transient ischaemic attack (TIA)

A transient ischaemic attack (TIA), often called a mini stroke, happens when the blood supply to part of the brain is cut off for a short time. The brain then doesn't get enough oxygen, and this can bring on sudden symptoms like those of a stroke.

A TIA doesn't last as long as a stroke, though. The effects only last for a few minutes or hours, and they clear completely within 24 hours.

• you suspect you or someone else is having a TIA or stroke

Do not drive if you suspect you have had a stroke or TIA (transient ischaemic attack).

The signs of a transient ischaemic attack (TIA) usually begin suddenly, just as they do in a stroke. The main symptoms of stroke can be remembered with the word FAST, which stands for:

• Face: the face might drop on one side, the person may not be able to smile or their mouth may have dropped, and their eyelid may droop
• Arms: the person may not be able to lift both arms and keep them there, because of weakness or numbness in one arm, or they might have weakness in one leg
• Speech: they might slur their speech or it might be garbled, or the person may not be able to talk at all even though they seem to be awake
• Time: it's time to phone 999 immediately if you see any of these signs or symptoms

A person having a TIA or a stroke might not have all of these symptoms. If you notice any of them, think of the possibility that the person is having a stroke.

The FAST symptoms pick up most strokes and TIAs. But a TIA sometimes causes other symptoms that appear suddenly, usually over a few seconds. These may include:

• complete paralysis of one side of the body
• sudden loss or blurring of vision
• dizziness
• confusion
• difficulty understanding what others are saying
• problems with balance and co-ordination

There may be other causes for these symptoms, however.

While a TIA is happening, there's no way to tell whether it's a TIA or a full stroke, so phone 999 immediately. Even if the symptoms disappear, you should still be assessed urgently by a health professional.

A TIA is a warning that you're at risk of having a full stroke. An assessment can help doctors decide the best way to reduce the chances of this happening.

A transient ischaemic attack (TIA) happens when the blood supply to part of the brain is cut off for a short time. The blockage clears before it does any significant damage. In a full stroke, the blood flow to your brain is disrupted for much longer, and that leads to more severe damage and problems that last.

Most TIAs are caused by a blood clot that has travelled to the blood vessels supplying the brain and blocked them.

A type of irregular heartbeat called atrial fibrillation can also cause a TIA. It can form blood clots that escape from the heart and get stuck in the blood vessels that supply the brain.

Anyone can have a transient ischaemic attack (TIA) or a stroke, but some things make you more likely to have one. These are:

• poor diet
• lack of exercise
• obesity
• smoking
• an excessive alcohol intake
• high cholesterol
• high blood pressure (hypertension)
• diabetes
• atrial fibrillation

You can make lifestyle changes to help control some of these risk factors. You may also need to take regular medicine.

If you have an irregular heartbeat because of atrial fibrillation, taking anticoagulant medicine will help reduce the risk of stroke.

If you've already had a stroke or TIA, these steps matter even more, because you're more likely to have another stroke in future.

Some risk factors you can't change, such as:

• age: people over 65 are most at risk of having strokes, although they can happen at any age, including in children
• family history: if a close relative (parent, grandparent, brother or sister) has had a stroke, your risk is likely to be higher
• ethnicity: if you're south Asian, African or Caribbean, your risk of stroke is higher, partly because rates of diabetes and high blood pressure are higher in these groups
• your medical history: if you've had a stroke, TIA or heart attack, your risk of stroke is higher

If you think you've had a transient ischaemic attack (TIA), see a doctor as soon as possible so a health professional can assess you.

A transient ischaemic attack (TIA) is often over very quickly, so you may have no symptoms left by the time you see a health professional.

Tell the person assessing you what symptoms you had and how long they lasted. This helps them rule out other conditions.

Even if your symptoms have gone, you might still need a neurological examination. It involves simple tasks that check your strength, sensation and co-ordination skills.

If a TIA is suspected, you should be started on medicine to lower the risk of another TIA or a stroke. The risk of another is highest in the days after a TIA or stroke, so start this medicine as soon as you are advised to.

If a transient ischaemic attack (TIA) is suspected, you'll be sent to a specialist for more tests as soon as possible. Please go for this assessment the moment it's available. Being seen quickly means you can get the right treatment to prevent another TIA or a stroke.

You will most likely see a doctor who specialises in strokes.

You might have a few tests to rule out other causes of your symptoms and to help find the underlying cause of your transient ischaemic attack (TIA).

You might need blood tests to see whether you have high cholesterol, and to check if you have diabetes.

An electrocardiogram (ECG) measures the electrical activity of your heart. Electrodes (small, sticky patches) are placed on your skin to do this. An ECG can pick up abnormal heart rhythms, which may be a sign of conditions like atrial fibrillation (where your heart beats irregularly).

A carotid ultrasound scan can show whether the arteries in your neck that lead to your brain are narrowed or blocked. A small probe (transducer) sends high-frequency sound waves into your body. When these sound waves bounce back, they create an image of the inside of your body.

Brain scans are not always necessary if you've had a TIA. You might have a magnetic resonance imaging (MRI) scan, which uses a strong magnetic field and radio waves to create an image of your brain. If an MRI scan is not suitable for you, you might have a computerised tomography (CT) scan instead. This type of scan uses a series of X-rays to produce an image of the inside of your brain.

Although the symptoms of a transient ischaemic attack (TIA) stop on their own, you'll still need treatment to help reduce the risk of another TIA or a full stroke.

The right treatment after a TIA can help lower your risk of having one. Your doctor will tell you about lifestyle changes you can make to reduce your stroke risk. They will also prescribe medicine to treat the underlying cause of your TIA, and you might need surgery as part of your treatment.

There are lifestyle changes that may help reduce your chances of having a stroke after a TIA, like:

• eating a healthy diet: a low-fat, low-salt, high-fibre diet is usually recommended, with plenty of fresh fruit, vegetables and whole grains
• exercising regularly: this can help lower your cholesterol level and keep your blood pressure at a healthy level
• stopping smoking if you smoke
• cutting down on the amount of alcohol you drink

Most people who've had a TIA will take medicine to reduce their chances of having a stroke or another TIA.

After a TIA, the aim is to reduce the risk of a stroke, especially in the first few days. To do this, a combination of treatments is usually recommended. Some of the treatments might include:

• antiplatelets like aspirin and clopidogrel
• anticoagulants like apixaban, edoxaban, rivaroxaban, dabigatran or warfarin
• medicine to lower your blood pressure (antihypertensives)
• statins to lower your cholesterol

The antiplatelet medicines need to be taken immediately. Others may only be started later, and these usually need to be taken long term.

A carotid endarterectomy is an operation to remove part of the lining of the carotid artery and any blockage in the artery. By unblocking the carotid arteries, it can reduce the risk of having a stroke or another TIA.