Investigations for unstable angina or a heart attack

Information for the public

As soon as possible, you should have:

drugs to relieve your pain if needed (such as glyceryl trinitrate [GTN] or an opioid) and regular checks to make sure you are not in pain
an electrocardiogram (ECG) to show how your heart is working (this may be done by a GP or a member of the ambulance service)
a single dose of aspirin to make your blood less 'sticky' and less likely to form blood clots (you should not have aspirin if you are allergic to it)
a test to see whether you need extra oxygen (you should be offered extra oxygen if you need it).

These should not delay you being taken to hospital if you need to go.

If you currently have chest pain or if you have signs of complications that need further investigation, you may need to go to hospital as an emergency for further tests and treatment. This will depend on whether you currently have chest pain and the results of your ECG.

You should not need to go to hospital as an emergency if you do not currently have chest pain and your ECG is normal, but you should have an assessment in hospital on the same day. If your chest pain was more than 3 days ago you should have an assessment, which may be done in hospital. If you don't currently have chest pain you should also be given advice about what to do if it returns.

During the assessment you should be asked to describe your pain and any other symptoms. You should also be asked if you have any history of coronary heart disease. Details of previous investigations or treatments you have had for similar symptoms of chest pain should be noted. You should also be assessed for cardiovascular risk factors. With your permission, your healthcare professional should carry out a physical examination to check your heart, and for any complications.

You may have repeated ECGs. Your blood should be checked for levels of a protein called troponin. Your troponin levels should be measured again in a second blood sample taken 3 hours after the first unless the levels in the first sample are normal and your healthcare professional thinks your risk of a heart attack is low. Raised levels of troponin may be a sign that you have had a heart attack, but they may also be raised if you have other conditions.

If you have unstable angina or have had a heart attack, you will be offered appropriate treatment.

If the results are not clear, your healthcare professional may ask to repeat some of the tests. This may involve a stay in hospital for observation.

Sometimes a chest X‑ray or a type of scan known as a chest CT (computed tomography) scan may be carried out to check whether you have any complications of unstable angina or a heart attack or whether your pain is caused by other conditions.

If your healthcare professional thinks that you may have stable angina, see tests used to diagnose stable angina for the care and investigations you should be offered.

If your chest pain is not related to your heart, but you have any cardiovascular risk factors, you should be offered advice and you may be offered treatment to help lower your cardiovascular risk.