Summary

• This test measures the level of a protein called troponin in your blood.
• Troponin tests are used, together with an electrocardiogram (ECG), to check to see if you have had a heart attack or have unstable angina. Angina is the name given to chest pain that’s caused by reduced blood flow.
• Troponin is a protein found in the cells of your heart muscle that helps it pump blood. When heart muscle cells are injured, troponins leak out into the bloodstream.
• By measuring the levels of troponins in your blood, your emergency doctors can assess whether you have had damage to your heart and if so, how severe it is.
• A high sensitivity troponin test can detect very low levels of troponin and diagnose heart attack very quickly.

What are troponins?

Your heart is a muscle that pumps blood throughout your body. Your blood carries oxygen which is needed by your body all the time. For your heart to function properly, it must have a continuous supply of blood. In a heart attack (or myocardial infarction), one of the arteries supplying blood to your heart becomes blocked. This means that blood flow is reduced or stopped entirely, the heart muscle cells are starved of oxygen, and they start to die. The longer the blockage is left untreated the more damage occurs.

Troponins are proteins found in your heart muscle cells – they help the muscle contract. As heart muscle cells die, troponins are released into your blood. There are three different troponins: troponin C (TnC), troponin T (cTnT) and troponin I (cTnI). When there is damage to the heart muscle, it is cTnI and cTnT which are released into the blood.

Why get tested?

Normally, troponin levels are very low in healthy people. Any rise can indicate some heart damage. They go up dramatically if you have a heart attack. The more damage there is, the greater the concentration of troponin in the blood. 

Having the test

Sample

Blood.

Preparation?
None.

Your results

Troponin levels usually rise within three or four hours of a heart attack, and then they start to fall back again. They can stay higher than normal for 10 to 14 days. Usually, you can expect to have troponin tests repeated over several hours to monitor your levels.

The rise or fall in troponin levels is important in working out whether you’ve had a heart attack or whether it is due to another heart problem. If you have a big rise in troponin levels, then it is highly likely that you’ve had a heart attack or some other form of heart damage.

Some people have higher troponin levels, and their levels don’t change. This is sometimes seen in heart problems such as myocarditis (inflammation of the heart muscle), weakening of the heart (cardiomyopathy), or congestive heart failure, chronic heart failure, high blood pressure (hypertension), kidney disease and some chronic inflammatory conditions that affect the heart.

Because troponin can rise due to problems other than a heart attack, a troponin test on its own can’t make the diagnosis. Your doctors will need to do a physical examination and an ECG at the same time.

There is an internationally agreed definition of heart attack that requires evidence of a significant increase in troponin concentration over time, together with evidence of a sudden reduction of heart muscle blood supply (ischaemia), ECG changes or imaging of heart changes.

Your emergency team will make treatment decisions based on your results. If your troponin levels are high and the ECG indicates an acute heart attack, you may need to have treatment to restore blood flow and oxygen levels. If your troponin levels are high but your ECG does not indicate a heart attack, your doctors will look at alternative causes.

More information

Pathology and diagnostic imaging reports can be added to your My Health Record. You and your healthcare provider can now access your results whenever and wherever needed.

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