Clinical Implications of Electrocardiograms for Patients With Non-ST-Segment Elevation Acute Coronary Syndromes in the Interventional Era

In patients with non-ST-segment elevation acute coronary syndromes, early risk stratification is crucial for appropriate management of this condition and for deciding whether early invasive strategies should be adopted. The electrocardioaram (ECG) has been extensively used for risk stratification, and the presence of ST-segment depression is an especially strong predictor of poor outcomes. Furthermore, quantitative analysis of ST-segment depression, ie, the degree and extent of ST-segment depression, and the time from symptom onset to the evaluation of ECG provide important information on prognosis. ST-segment elevation in lead aVR in addition to ST-segment depression in other leads is a very valuable marker of left main and/or 3-vessel disease. This review explores the clinical importance of the ECG in the current interventional era. (Circ J 2009; 73: 798-805)