Use and interpretation of high sensitivity cardiac troponins in patients with chronic kidney disease with and without acute myocardial infarction

It is well known that the population with chronic kidney disease (CKD) is at greater risk for cardiovascular disease and death than the general population. The use and interpretation of high sensitivity cardiac troponin (hs-cTn) assays have been particularly challenging in these patients with the majority having elevated levels at baseline. The diagnostic accuracy of acute myocardial infarction (AMI) may be decreased in patients with CKD when using these newer troponins. In order to improve the sensitivity and specificity for the diagnosis of AMI, one must look at the change in cTn and consider using higher cut-off values. In asymptomatic patients with CKD, research has shown increased prevalence of cardiovascular risk factors and underlying structural heart disease with increasing cTn levels. Prognostically, elevated cTn has been associated with adverse outcomes including incident heart failure and cardiovascular mortality. The purpose of the review is to evaluate hs-cTn in patients with CKD for the diagnosis of AMI and for the prognostic significance of elevated levels in CKD patients without AMI. Although the underlying etiology of persistently elevated cTn in the CKD population remains unclear, the review will also evaluate studies attempting to explain whether the source of cTn is from increased cardiac production versus decreased renal clearance. Further longitudinal studies are required in order to bridge the gap between the prognostic importance of elevated cTn and clinical management to prevent symptomatic cardiac disease.