Significance of early and late anterior precordial ST-segment depression in inferior myocardial infarction.
In 24 patients with acute inferior myocardial infarction, the presence and duration of ST-segment depression in lead V2 correlated with the presence of left anterior descending coronary artery (LAD) stenosis and depressed left ventricular ejection fraction (LVEF). Early changes in lead V2 (within 4 hours after the onset of pain) were 67% sensitive and only 42% specific, whereas late changes (after onset of inferior Q waves and more than 6 hours after the onset of pain) were 42% sensitive, but 100% specific for the presence of LAD stenosis or decreased LVEF or both. Thus, in patients with inferior infarction, only the late repolarization change is helpful in identifying those with LAD stenosis or decreased LVEF. The absence of lead V2 ST-segment depression on either early or late electrocardiograms does not imply a normal LAD or LVEF.
D000328:Adult; D000368:Aged; D003251:Constriction, Pathologic; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology*; D013318:Stroke Volume