Elevation of cardiac troponins above the 99th percentile of a healthy reference population is established as a marker for myocardial cell damage and is crucial for the diagnosis of myocardial infarction. In addition, corresponding clinical evidence of acute myocardial ischemia i.e. symptoms, changes in the electrocardiogram (ECG), wall motion abnormalities or suggestive angiographic findings are required for the diagnosis of myocardial infarction. Using modern highly sensitive assays myocardial infarction can be detected more frequently and earlier. On the other hand myocardial infarction can be ruled out with a higher diagnostic accuracy. Cardiac troponins are specific for myocardial cell damage but not for myocardial infarction and can be elevated in numerous other disease states. In these cases myocardial injury can be diagnosed independently of myocardial ischemia. Typical dynamics with rise and fall of troponin levels can distinguish acute myocardial injury (e. g. pericarditis/myocarditis and pulmonary embolism) from chronic myocardial injury (e. g. cardiomyopathy). Clinically, highly sensitive troponin assays are currently recommended in addition to the 0/3 h and 0/1 h algorithms for rapid inclusion or exclusion of myocardial infarction.
Keywords: Acute coronary syndrome; Cell damage; Ischemia; MINOCA; Myocardium.