High-sensitivity troponin in chronic kidney disease: Considerations in myocardial infarction and beyond

Acute myocardial infarction (MI) represents one of the most common hospital encounters, with significant short-term and long-term morbidity and mortality, and frequently occurs in patients with chronic kidney disease (CKD). Cardiac troponin is an exquisitely sensitive biomarker for myocardial injury and plays an essential role in the diagnosis, risk-stratification, and management of MI. In 2017, the United States Food and Drug Administration approved Roche Diagnostics' 5^th generation high-sensitivity cardiac troponin (hs-cTn) for clinical use. Whilst the improved analytical sensitivity of these new high-sensitivity troponin assays facilitate early diagnosis of MI, it also frequently identifies troponin elevations above the conventional reference threshold in the context of non-coronary conditions such as renal dysfunction, and can represent a major diagnostic challenge to clinicians. Furthermore, the optimal management strategy of patients with troponin elevation and high comorbidity burden, a common issue in patients with CKD, remains undefined. In recent years, there has been substantial research and progress undertaken in this rapidly evolving area. In this review, we aim to provide clinicians with an overview of hs-cTn in the setting of CKD as well as an update on its application and the particular considerations involved in the management of myocardial infarction, stable coronary artery disease and myocardial injury in this high risk population.