Cardiac troponin level elevations not related to acute coronary syndromes

Over the past 2 decades, cardiac troponins (cTn) have emerged as the preferred biomarkers for the noninvasive detection of myocardial injury. In conjunction with typical clinical findings of ischaemia, elevated cTn levels in blood confirm a diagnosis of myocardial infarction. However, neither cTnT or cTnI are exclusively released as a result of ischaemic myocardial cell necrosis, but also with numerous nonischaemic acute and chronic cardiac conditions, such as myopericarditis, toxic injury, or severe cardiac overload. With the advent of high-sensitivity assays, causes of cTn elevation not related to an acute coronary syndrome (ACS) have become common findings in patients with chest pain and in those with acute or chronic systemic disorders. Elevated cTn levels in blood are associated with increased rates of cardiac events and mortality, independently of the underlying disease. However, the clinical conditions leading to cTn release in patients who do not have ACS, and the appropriate diagnostic and therapeutic strategies for these individuals, are largely unknown. Here, we provide an overview of the many causes and the prognostic importance of the release of cTn not related to ACS. We also recommend strategies to discriminate between ischaemic and nonischaemic cTn elevation, and describe the clinical evaluation of these patients.