The ECG in acute myocardial infarction

Abstract

The initial ECG is the most rapid and readily available tool in the emergency department for the evaluation of patients presenting with suspected myocardial infarction. However, studies have shown that the initial ECG is diagnostic of acute myocardial infarction in only a minority of patients. This paper discusses the importance of the initial ECG and other information in aiding the disposition of patients with suspected myocardial infarction. Classic electrocardiographic descriptions are discussed as well as the newer terminology of Q wave versus non-Q wave infarction and ST segment versus T wave infarction. A brief review is made of the electrophysiology of the ECG changes seen in myocardial infarction. Finally, clinical studies are presented that establish a definite role for the use of the initial ECG.