RT Journal Article SR Electronic T1 Acute Myocardial Infarction: Definition, Diagnosis, and the Evolution of Cardiac Markers JF American Society for Clinical Laboratory Science JO Clin Lab Sci FD American Society of Chemistry and Laboratory Science SP 200 OP 204 DO 10.29074/ascls.2018000687 VO 31 IS 4 A1 Oliveira, Ana A1 Glasgow, Krystle A1 Josephat, Floyd A1 Estes, Robert A1 George, Remo A1 Gilford, Tosi A1 Giordano, Samantha A1 Hallman, Heather A1 Li, Wei A1 Xavier, Neena A1 Marie Chiasera, Janelle YR 2018 UL http://hwmaint.clsjournal.ascls.org/content/31/4/200.abstract AB In the United States, heart disease is the leading cause of death and accounts for one in every four deaths each year. Coronary artery disease (CAD) is the most common type of heart disease and is the principal source for deaths due to heart disease. CAD refers to a group of diseases including stable angina, unstable angina, and myocardial infarction (MI). An estimated 735,000 individuals suffer an MI annually, with the majority (roughly 525,000) being first-time heart attacks. The current diagnosis of MI is based on the rise and fall of cardiac markers, preferably troponin, with at least one measurement being above the 99th percentile upper reference limit, with strong clinical evidence. The advancement in cardiac troponin assays has provided an opportunity for clinicians to more quickly identify acute coronary disorders and to determine the best treatment protocol for patients. The fifth-generation assays, known as high-sensitivity cardiac troponin assays, were Food and Drug Administration approved in the United States only in 2017. As we take a closer look at the high-sensitivity troponin assay, we need to take into consideration issues related to this assay in all steps of the testing process (preanalytical, analytical, and postanalytical). In this article, we define MI and the challenges that come with diagnosing MI, and the history and evolution of cardiac markers over the years are summarized. The future of MI and cardiac disease identification is described by identifying the advantages and disadvantages of high-sensitivity troponin assays.