Cardiac troponins are commonly used in
emergency departments across the developed world to identify causes of
chest pain.
Troponin levels above 0.2ng/ml in blood taken up to 12 hours after the onset of pain are associated with a much greater risk of subsequent cardiac events. Conversely, troponin levels which remain low signify a good prognosis and patients can often be sent home.
The troponins themselves are part of the heart muscle and are escape into the blood when the sarcomere (muscle cell) is damaged, usually by ischaemia from coronary artery disease.