Was it a heart attack?BMJ 2002; 324 doi: https://doi.org/10.1136/bmj.324.7334.377 (Published 16 February 2002) Cite this as: BMJ 2002;324:377
Troponin positive acute coronary syndrome versus myocardial infarction
- Charles J McKenna, international fellow,
- J Colin Forfar, consultant cardiologist
- Department of Cardiology, John Radcliffe Hospital, Oxford OX3 9DU
The World Health Organization's classic definition of acute myocardial infarction requires that at least two of the following three criteria are met: a history of typical symptoms of ischaemic chest discomfort; evolutionary electrocardiographic tracings involving the development of Q waves; and an increase in the creatinine kinase level greater than twice the upper reference limit.1 While this definition is clear cut, many patients who have had myocardial infarction will be excluded. Recent developments in the detection of small quantities of myocardial necrosis using serum cardiac troponin levels have prompted a new definition of myocardial infarction. This may well lead to an increase in the number of patients diagnosed and improved patient outcomes, but it may also confuse clinicians, epidemiologists, and most importantly patients themselves.
Myocardial infarction without ST elevation
Acute coronary syndromes without accompanying elevation of the ST segment on the presenting standard 12 lead electrocardiogram cover a range from unstable angina to non-ST elevation or non-Q myocardial infarction. Patients in the latter category can go on to fulfil the WHO definition of myocardial infarction by developing Q waves on serial electrocardiographic tracings during their index admission. Specific patterns …