The field of diagnostic cardiac
biomarkers has grown exponentially since the development of an assay for
aspartate transaminase activity to diagnose
myocardial infarction in 1954. The clinician now has a vast array of clinical tools, which include
biomarkers of
inflammation, ischaemia and
necrosis as well as sensitive imaging technology and coronary anatomy intervention at their disposal when evaluating
acute coronary syndromes. Previously the World Health Organisation (1979) defined a
myocardial infarction (MI) in the presence of two of the following triad: History of
chest pain, electrocardiographic (ECG) changes and a rise in cardiac
enzymes to twice the upper limit of normal. At this time,
creatine kinase and its MB
isoenzyme were the preferred
biochemical markers. The clinical requirements of early diagnosis, risk stratification and effective treatment have stimulated the development of numerous new and cardiac specific
biomarkers (e.g. cardiac
troponins). Cardiac
troponins are now integral to the diagnosis of MI and have led to the reclassification of MI into either ST elevated MI (
STEMI) or non-ST elevated MI (
NSTEMI). Subsequent to the release of each new cardiac specific assay there typically follows an array of studies supporting or refuting its efficacy. Many cardiac
biomarkers originally proposed with high sensitivity and specificity for ACS are now of questionable clinical value or require the addition of significant caveats once they have been fully evaluated. Indeed, acute exercise often stimulates perturbations in cardiac
biomarkers; such as elevations in
creatine kinase, cardiac
troponins or reductions in
Ischemia Modified Albumin (IMA). Such an influence of exercise upon commercially available cardiac
biomarkers may hamper or distort the viability of such assays in the clinical arena. The purpose of this review is to examine the influence of exercise upon a number of established and novel cardiac
biomarkers, including markers of
necrosis,
inflammation, cardiac function and
ischemia. We will also address the clinical relevance of such exercise-induced perturbations.