Myocardial infarction redefined: the new ACC/ESC definition, based on cardiac troponin, increases the apparent incidence of infarction

• Published in: British heart journal 2002-10, Vol.88 (4), p.343-347
• Main Authors: Ferguson, J L, Beckett, G J, Stoddart, M, Walker, S W, Fox, K A A
• Format: Article
• Language: English
• Subjects: ACC; Acute coronary syndromes; Adult; Aged; Aged, 80 and over; American College of Cardiology; Biological and medical sciences; Biomarkers - blood; Cardiac patients; cardiac troponin I; Cardiology; Cardiology. Vascular system; Cardiovascular disease; Cardiovascular Medicine; coefficient of variation; Coronary heart disease; Coronary vessels; creatine kinase; Creatine Kinase - blood; Creatine Kinase, MB Form; Diagnosis; epidemiology; ESC; European Society of Cardiology; Evaluation; Female; Heart; Heart attack; Heart attacks; Humans; Isoenzymes - blood; Laboratories; Male; Medical sciences; Medical tests; Middle Aged; myocardial infarction; Myocardial Infarction - blood; Myocardial Infarction - diagnosis; Pain; Prospective Studies; Sensitivity and Specificity; Statistics; Studies; Troponin - blood; Values; WHO; World Health Organization
• ISSN: 1355-6037; 0007-0769; 1468-201X
• DOI: 10.1136/heart.88.4.343

Objectives: To investigate the impact of the redefinition of the diagnostic criteria for myocardial infarction on its apparent incidence in a non-selected and representative series of patients admitted with acute chest pain. Design: Single centre prospective study. Setting: Medical assessment unit and cardiology wards of an inner city university hospital. Patients: 80 consecutive patients aged over 25 years admitted with suspected ischaemic acute chest pain (excluding those where the ECG indicated definite myocardial infarction). Interventions: Measurement of concentrations of conventional cardiac biomarkers (creatine kinase and its MB isoenzyme, CK-MB) and concentrations of the highly specific diagnostic indicator of myocardial damage, cardiac troponin I (cTnI) 12–24 hours after the onset of acute chest pain. Main outcome measures: Frequency of myocardial infarction as assessed by conventional diagnostic criteria (creatine kinase and CK-MB) plus clinical symptoms of infarction, versus frequency of infarction based on high sensitivity troponin assays. Results: Among patients with acute coronary syndromes but non-diagnostic ECG changes, 40% (32/80) fulfilled the new criteria for myocardial infarction using high sensitivity cTnI measurement, compared with 29% (23/80) using the conventional diagnostic criteria for myocardial infarction. Conclusions: The implications of the redefinition of myocardial infarction on patients, their care, and the use of health care resources are substantial.