Transient ischaemic attack (TIA)

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1 Stroke Helpline: Website: stroke.org.uk Transient ischaemic attack (TIA) A transient ischaemic attack or TIA is similar to a stroke, but the symptoms do not last as long. However, it should still be treated as a medical emergency. This factsheet explains how to recognise a TIA using the FAST test, the assessments and treatments that should happen afterwards and what you can do yourself to reduce the risk of a further TIA or stroke. A transient ischaemic attack (TIA) is often called a mini-stroke or mild stroke. The symptoms are very similar to those of a full-blown stroke, but they only last for a short time, anything from a few minutes up to 24 hours. If you have had a TIA you will recover completely within about a day. If your symptoms have lasted longer than 24 hours you have not had a TIA, you may have had a stroke. A TIA is a sign that part of the brain is not getting enough blood and that there is a risk of a more serious stroke in the future. Each year approximately 65,000 people have a first TIA. There is no way of telling whether a TIA or stroke is occurring during the first few hours, so a TIA should be treated as an emergency and you should seek urgent medical attention for assessment. GE and GE Monogram are trademarks of General Electric Company. The printing of this factsheet has been supported by a grant from GE Healthcare. The Stroke Association retains independent editorial control over all content. What are the symptoms of a TIA? The FAST (Face Arms Speech Time) test helps people to quickly recognise the key symptoms of a TIA or stroke: Facial Weakness: Can the person smile? Has their mouth or eyelid drooped? Arm Weakness: Can the person raise both arms? Speech problems: Can the person speak clearly and understand what you say? Time to call 999. If the person fails any one of these tests, they should seek urgent medical attention. Other symptoms of a TIA or stroke may include: Weakness, numbness, clumsiness or pins and needles on one side of the body, for example, in an arm, leg or the face Loss of or blurred vision in one or both eyes Sudden memory loss or confusion Slurred speech or difficulty finding some words. If you, or someone you know, have any of 1

2 the symptoms of a TIA, you should contact a doctor urgently. Though the symptoms may be due to something quite different from a TIA, such as hypoglycaemia (low blood sugar), migraine or an epileptic seizure, the sooner the symptoms are investigated, the more likely a doctor will be able to say whether it was a TIA or not. What causes a TIA? An adequate blood supply is vital to the functioning of the brain. It brings oxygen, glucose and other nutrients, and removes waste products such as carbon dioxide. Although the brain is only two to three per cent of the total body weight, it takes 14 per cent of the output of the blood from the heart. Four large blood vessels, two either side of the windpipe at the front of the neck (known as the carotid arteries), and two alongside the top of the spine (known as the vertebral arteries) carry oxygenated blood up into the head. The four arteries join together inside the skull to form a ring-shaped arrangement known as the circle of willis. From here, six major arteries branch off into smaller vessels which supply blood to different parts of the brain. If a blood clot or other debris clogs one of these tiny blood vessels, the blood supply to nearby brain cells may be disrupted. If this is temporary, a TIA may occur. If the disruption to the blood supply is permanent, it may result in a stroke. Sometimes a TIA occurs when a blood clot from a blood vessel in another part of the body or from the heart moves upwards into one of the brain s arteries - this is called an embolism. Very rarely, symptoms of a TIA are 2 due to bleeding (haemorrhage) in the brain. What tests will I have? Your doctor will want to ask you some questions to help distinguish between a TIA and other possible causes, and to give you a risk score of a further stroke. This is known as an ABCD2 scale and stands for age, blood pressure, clinical features (symptoms) and duration of symptoms (how long they have lasted for). Risk scores range from 0 (low risk) to 7 (high risk): A - age (1 point for aged 60 or over) B - blood pressure (1 point for BP 140/90 or higher) C - clinical features (2 points for weakness on one side; 1 point for speech disturbance without weakness) D - duration of symptoms (2 points for 60 minutes or longer; 1 point for minutes) 1 point is added for the presence of diabetes. If your risk of further stroke is assessed as high (4 or above) after a TIA, you should be referred on to a specialist (a stroke physician or neurologist) and, wherever possible, receive an MRI brain scan. The referral and brain scan should both be within 24 hours of the symptoms. Otherwise, you should still be seen by a specialist within 7 days of you noticing symptoms, by being referred to a TIA clinic. TIA clinics are usually run at hospitals, with a specialist stroke nurse in attendance. In Scotland these may be known as neurovascular clinics. In some of the more rural areas of Scotland (such as Orkney), telemedicine is sometimes used. This means that stroke specialists in Aberdeen can

3 carry out consultations using a video link, making sure that everyone has access to assessment and treatment. There is also a TIA Hotline in some areas of Scotland (e.g. Lothian) enabling GPs to speak directly to a stroke consultant for advice on diagnosing and assessing people who have had a TIA. Following a TIA, you may have some or all of the following tests: MRI (Magnetic resonance imaging) or CT (computed tomography) brain scan blood pressure measurements blood tests to check clotting, blood sugar and cholesterol levels electrocardiogram (ECG) to look for an irregular heart rhythm chest x-ray to exclude other health problems ultrasound (Doppler scan) of the carotid arteries to check blood flow this should happen within one week of your symptoms if the specialist thinks your carotid artery may be (partially) blocked echocardiogram to check for various forms of heart disease. What treatments are available? If the specialist confirms you have had a TIA, your treatment will be aimed at trying to prevent another TIA or a stroke. In addition to making certain lifestyle changes (see what can I do to lower my risk? overleaf), it is likely that you will be prescribed at least one of the following medications: blood thinning medication high blood pressure medication high cholesterol medication. Blood thinning medication After a TIA or a stroke, many people are prescribed drugs to reduce the risk of clots forming in their blood and blocking their carotid arteries or other blood vessels in their brain (see our factsheet F11, Blood thinning medication after stroke for more information). The majority of people will be given aspirin immediately. Some people may be prescribed a combination of aspirin and a modifiedrelease drug called dipyridamole - particularly in the two years following a TIA or stroke. Another anti-clotting drug called clopidogrel is often prescribed if you cannot take aspirin because of aspirin s possible side effects. It may also be given if you have had a TIA despite already taking aspirin or if you have arterial disease affecting other parts of your body. If you have had a TIA due to a blood clot arising from your heart (often due to atrial fibrillation, an irregular heart rhythm) you are likely to be prescribed warfarin to prevent further clots. Warfarin is a drug that slows down the clotting process in the blood. It is rarely appropriate to take both aspirin and warfarin together as there is an increased risk of internal bleeding. Those taking warfarin are monitored carefully to ensure the dose is correct and the blood is not becoming too thin. Unless there is considered to be a high risk of complications, warfarin should be offered to patients of all ages. There is currently research underway on new generation anticoagulants such as dabigatran and rivaroxaban for reducing the risk of stroke in people with atrial fibrillation. These medications will not need such careful monitoring as warfarin. High blood pressure medication If a series of readings show your blood pressure is raised, you may then have some 3

4 further tests of your body s functioning (like giving a urine sample and having an ECG) so that the doctor can decide upon the best blood pressure drugs to prescribe (see our factsheet F6, High blood pressure and stroke). There are many different medications available and it may take a while to find the right drug in the right dose to suit you. If you have any problems with the drug you are given, tell your doctor, who may be able to change or adapt your prescription. Many people take two or three different blood pressure medications to control their blood pressure. High cholesterol medication If your cholesterol level is raised, you will be given advice on how to reduce the amount of fat in your diet (our factsheet F8, Healthy eating and stroke also gives advice). You may also be prescribed a drug to lower your cholesterol level. The most commonly prescribed drugs are called statins and, as with drugs for high blood pressure, there are several available. If you have any concerns about the sideeffects of medication, it is recommended that you do not stop taking it but consult your GP. Will I need surgery? If a scan shows your carotid arteries have become partially blocked, resulting in poor blood flow, you may be advised to have an operation called a carotid endarterectomy as soon as possible within two weeks of your TIA to lower the risk of a major stroke. Fatty material may have built up in the wall of one or both arteries, and blood cells and other debris may have become stuck to 4 the surface. This makes the artery much narrower, and debris can break off and be carried by the blood to block an artery in the brain. Carotid endarterectomy involves removing part of the lining of the damaged artery and any blockage, so that blood flow is improved and the risk of debris breaking off is reduced. It is useful for people who have severe but not total blockage. Though the results are usually very good, carotid endarterectomy carries with it a small risk of stroke. As with any major surgical procedure, carefully discuss the situation with your doctor before making a decision. There are two alternatives to carotid endarterectomy: carotid stenting and carotid angioplasty. These operations are carried out under local anaesthetic and are less invasive. With each operation, a small tube is passed up through the femoral artery in the groin to the carotid artery. Angioplasty involves inflating a small balloon in the artery to widen the passage. Stenting is the same as angioplasty to begin with but then includes a small wire mesh being inserted into the artery to keep it open (see our factsheet F40, Carotid artery disease for more details). What can I do to lower my risk? Anyone who has had a TIA is at greater risk of having another TIA or stroke. There are several things you can do yourself to reduce your risk. (Stroke Association has publications on all these issues. Call for more information.) Give up smoking. Smoking causes the arteries to become narrowed and makes the blood more likely to clot. Giving up can be difficult, so ask your GP about

5 attending a stop-smoking clinic or other help with stopping smoking. Eat at least five portions of fruit and vegetables each day. There is some evidence that a diet rich in fruit and vegetables, which contain protective substances called antioxidants, reduces the risk of stroke by protecting blood vessel walls from damage. Reduce your intake of salt. Salt raises blood pressure. Don t add salt to your food and avoid processed foods that contain a lot of salt. If you have high blood pressure or high cholesterol levels, ensure that you have regular check-ups and keep in touch with your GP. Limit the amount of fat you eat. Try to limit the amount of fat you use in cooking and stick to vegetable, seed and nut oils, rather than margarine and butter. Avoid fatty foods such as pies, pastries and ready-meals. Limit the amount of sugar you eat. Natural sugars found in fruit are healthy, but those added to food and drinks can be high in calories and often have no nutritional benefit. Always check the label. More than 15g of sugar per 100g is a high level. Reduce your alcohol intake and avoid binge drinking. Excessive alcohol can raise blood pressure, while binge drinking increases the risk of a blood vessel bursting and causing bleeding into the brain. The current recommended guidelines are two to three units for women and three to four units for men per day. (A standard glass of wine is about two units, a single measure of spirit is one unit and a pint of five per cent beer or lager is three units.) Increase your level of physical activity. Regular exercise can reduce the risk of stroke by lowering blood pressure, assisting with weight loss and altering the balance of fats in the blood. Thirty minutes of activity five days a week is enough to reduce your risk of stroke. This can be one 30 minute session or several shorter sessions a day. Useful organisations All organisations listed are UK wide unless otherwise stated. Stroke Association Stroke Helpline: Website: stroke.org.uk info@stroke.org.uk Contact us for information about stroke, emotional support and details of local services and support groups. Atrial Fibrillation Association (AFA) Tel: (24 hour) info@atrial-fibrillation.org.uk Website: Provides information, support and access to treatments for Atrial Fibrillation (AF). Blood Pressure Association Tel: Information Line: Website: Website: Has a wide range of information on stroke and hypertension (high blood pressure), treatments and lifestyle. Brain & Spine Foundation Tel: helpline@brainandspine.org.uk Website: Carry out research and develop education to help prevent disorders of the brain and spine. Has information about subarachnoid 5

6 haemorrhage and vascular malformations of the brain. British Heart Foundation (BHF) Heart Helpline: BHF Order Line: Website: Provides information about TIA and vital lifestyle changes aimed at reducing the risk of stroke and related heart conditions. Chest, Heart and Stroke Scotland (CHSS) Advice Line: Website: Provides information and support to people affected by chest, heart or brain attacks (stroke). Disclaimer: The Stroke Association provides details of other organisations for information only. Inclusion in this factsheet does not constitute a recommendation or endorsement. Glossary of terms ABCD2 = a scale to predict the risk of a stroke following a TIA Antiplatelet = blood thinning medication Carotid endarterectomy = operation to remove the inner lining of the carotid artery CT = computerised tomography (a type of brain scan) Doppler Scan = an ultrasound scan Echocardiogram = a test that uses sound waves to scan your heart ECG = electrocardiogram (a test that records the electrical impulses produced when the heart beats) Embolism = something travelling within the blood stream which should not be present, such as a blood clot, air bubble or fat globule FAST = a test to recognise the common signs of a stroke Haemorrhage = a bleed Ischaemic = interruption to blood flow caused by a blockage MRI = magnetic resonance imaging (a type of brain scan) TIA = transient ischaemic attack Produced by the Stroke Association s Information Service. For sources used, visit stroke.org.uk Stroke Association Factsheet 01, version 02, published April 2012 (next revision due June 2012). Item code: A01F01 Stroke Association is a Company Limited by Guarantee, registered in England and Wales (No 61274). Registered office: Stroke Association House, 240 City Road, London EC1V 2PR. Registered as a Charity in England and Wales (No ) and in Scotland (SC037789). Also registered in Isle of Man (No 945), Jersey (NPO 369) and serving Northern Ireland. 6