High-sensitivity cardiac troponins in health and disease

Diagnosing acute myocardial infarctions has improved thanks to a highly sensitive method of measuring a cardiac-specific protein (troponin T or I) in the blood. This method also makes it possible to measure troponin levels in healthy individuals. A disadvantage is that elevated troponin levels may be observed in individuals without an infarction as well.

This dissertation found that troponin T exhibits a circadian rhythm in clinically stable individuals with elevated troponin levels. These fluctuations are significant enough to exceed the cut-off value for infarctions. The average clinical relevance is therefore limited and the circadian rhythm may offer an explanation for individual patients whose symptoms do not correspond to the troponin T concentrations. In the case of troponin I, no circadian rhythm was observed.

Troponin may be a valuable mortality predictor in healthy individuals. That said, troponin T has better predictive values than troponin I. In the case of endurance sports, there appears to be a difference between the release of troponin during a myocardial infarction and when practicing an endurance sport.