Electrocardiographic diagnosis of non-ST-segment elevation acute coronary syndromes: current concepts for the physician.

With several myocardial infarction (MI) registries reporting a decline in the incidence of ST-elevation MI (STEMI) and an increase in non-ST-elevation MI (NSTEMI) and unstable angina (UA), it is important that future healthcare resources are directed towards this increased volume of patients, ECG technology, core to the early diagnosis of these patients, has lagged behind relative to other techniques and little progress has been as far as acute coronary syndrome triage is concerned beyond ST-segment deviation. We present a review of the literature on current electrocardiographic changes which will allow admitting physicians to better risk stratify those patients with "non-diagnostic ECGs." These ECGs may become diagnostic with careful evaluation, use of serial ECGs and when additional lead sets are used.