Troponin: think before you request one

Acute myocardial infarction (ACS) is one of the most common presentations in acute hospital settings. Troponin (cTn) has emerged as one of the most sensitive biochemical markers for the diagnosis of ACS. However, if used inappropriately and in the absence of true clinical context then it can be elevated in a number of non cardiac conditions and lead to false clinical diagnosis, inappropriate workup, and increased patient stay in hospital. The cost of unnecessary clinical testing is another aspect of the problem. At Royal Gwent Hospital in Newport (one of the busiest district general hospitals in Wales) we retrospectively analysed the nature of troponin requests over a random period of one week, specifically looking for the indications and final diagnostic impact. In many cases it was found that requests were made without any clinical justification. One of the main and probably unavoidable reasons for this was that requests were made from triage before patient was assessed by a clinician. However, steps were taken to clarify common clinical indications for suspected cardiac diagnosis in which troponin was useful. Additionally, the "tick box" practice for inappropriate laboratory investigations was discouraged. A repeat audit was done on similar basic principles and a measurable improvement was identified, with a potential for significant impact in future.