How to use high-sensitivity cardiac troponins in acute cardiac care

Recommendations for the use of cardiac troponin (cTn) measurement in acute cardiac care have recently been published.1 Subsequently, a high-sensitivity (hs) cTn T assay was introduced into routine clinical practice.2 This assay, as others, called highly sensitive, permits measurement of cTn concentrations in significant numbers of apparently illness-free individuals. These assays can measure cTn in the single digit range of nanograms per litre (=picograms per millilitre) and some research assays even allow detection of concentrations 10% at the 99th percentile URL limiting that ability.5–7 However, the less precise cTn assays do not cause clinically relevant false-positive diagnosis of acute myocardial infarction (AMI) and a CV <20% at the 99th percentile URL is still considered acceptable.8 We believe that hs-cTn assays, if used appropriately, will improve clinical care. We propose criteria for the clinical interpretation of test results based on the limited evidence available at this time. ‘Sensitive’ and ‘high-sensitive’ are terms often used by manufacturers to describe their assays for marketing purposes. In some cases, it reflects higher sensitivity than former assays developed by the same company, and in other situations it reflects a higher sensitivity than most assays on the market. Although there is still no consensus regarding when the terms ‘sensitive’ and ‘high-sensitive’ should be applied, we advocate that cTn assays should be labelled ‘high-sensitive’ only if they fulfil the analytical criteria suggested by …