Recurrent chest pain, falsely raised troponin and assay interference

Cardiac troponin assays have revolutionized the assessment of acute chest pain because of their sensitivity, specificity and ability to predict clinical outcomes.1 The most recent (fourth) Universal Definition of Myocardial Infarction refines the classification of myocardial injury and infarction.2 Using this classification, we describe a young patient who met diagnostic criteria for chronic myocardial injury. A 15-year-old girl attended the emergency department (ED) with sharp chest pain, worse lying flat. Physical examination showed no abnormality and an electrocardiogram, chest X-ray and echocardiogram were normal. Cardiac troponin T concentration measured by a high-sensitivity assay (hsTnT; Roche Elecsys) was elevated at 53 and 55 ng/l 3 h later. A diagnosis of myopericarditis was made and ibuprofen was prescribed. She attended a follow-up appointment at the ambulatory cardiology unit (ACU) where the diagnosis was reinforced and a 3-month course of colchicine was prescribed. Over the subsequent 21 months she attended the ED a further nine times (four of which were followed by inpatient cardiology admission) and the ACU a further five times (Table 1). The hsTnT concentration was above the 99th percentile upper reference limit on every one of the 21 occasions it was measured.