A number of conditions can lead to an elevation in cardiac marker level, the most important one being myocardial infarction (MI), commonly known as a heart attack. Many of the markers are enzymes; the term "cardiac enzymes" is sometimes used. However, not all the markers are enzymes. Troponin for example is not an enzyme in formal terms.
Aspartate Amino transferase was perhaps the first biochemical marker to be used; it was described in 1954. With the advent of electrophoresis method walked in Creatine Kinase and Lactate Dehydrogenase iso enzymes. The use of cTnT brought about a revolution in 1992. The introduction of Cardiac troponins heralded a new age in the diagnosis and treatment or management of a broad spectrum of diseases.