ABSTRACT
Serum troponin levels peak at 12 hours post-infarct and remain elevated for up to 10 days. The sensitivity of troponin in the diagnosis of myocardial infarction has been shown to be as high as 100% when measured 12 hours after the onset of symptoms. This compares with sensitivities as low as 21% when measured within the first 6 hours of symptoms. Therefore, serum troponin levels should be measured no less than 12 hours after the onset of symptoms. A negative serum troponin measured 12 hours after the onset of symptoms means that infarction is unlikely, but not impossible. Therefore, in this situation, a second troponin sample should be taken after a further 12 hours if the diagnosis remains uncertain. Troponin may also be elevated in other conditions, such as myocarditis, arrhythmia and pulmonary infarction, but to a lesser extent than with myocardial infarction.
