Interpreting troponin elevations: do we need multiple diagnoses?

Abstract

The expanded ability to detect myocardial injury using very sensitive and specific biomarker assays has been a major factor in the evolution of the definition of acute myocardial infarction (MI). This is clearly evident in the ‘Universal Definition of Myocardial Infarction’ recently developed by a joint task force of experts on behalf of the ESC, ACCF, AHA, and WHF (European Society of Cardiology, American College of Cardiology Foundation, American Heart Association, and World Heart Federation).1 In a clinical setting consistent with myocardial ischaemia, criteria are presented for defining acute MI that include a rise and/or fall in cardiac biomarkers together with symptoms of ischaemia, and/or appropriate ECG changes, and/or imaging evidence of a new regional wall motion abnormality or loss of myocardium. The task force developed a clinical classification of different types of MI that can be briefly summarized as: This multi-component scheme appears to add complexity in an area that can be quite confounding because of the multiple terms used to describe myocardial ischaemia/infarction in all of its various manifestations. This includes differentiating myocardial damage associated with ST elevation (STEMI) from that occurring without ST elevation (non-STEMI). Patients with a sudden change in cardiac status are often admitted to the hospital with a diagnosis of acute coronary syndrome (ACS), but ACS is not included in the ICD-9-CM codes.2 Intermediate coronary syndrome (code 411.1), which includes impending infarction, preinfarction angina, or unstable angina, can be used as a …