Clinical implications of anterior S-T segment depression in patients with acute inferior myocardial infarction

Am J Cardiol. 1982 Sep;50(3):428-36. doi: 10.1016/0002-9149(82)90306-x.

Abstract

To assess various factors associated with anterior S-T segment depression during acute inferior myocardial infarction, 47 consecutive patients with electrocardiographic evidence of a first transmural inferior infarction were studied prospectively with radionuclide ventriculography an average of 7.3 hours (range 2.9 to 15.3) after the onset of symptoms. Thirty-nine patients (Group I) had anterior S-T depression in the initial electrocardiogram and 8 (Group II) did not have such "reciprocal" changes. There was no difference between the two groups in left ventricular end-diastolic or end-diastolic volume index or left ventricular ejection fraction. Stroke volume index was greater in Group I than in Group II. There were no group differences in left ventricular total or regional wall motion scores. A weak correlation existed between the quantities (mV) or inferior S-T segment elevation and reciprocal S-T depression. No relation between anterior S-T segment depression and the left ventricular end-diastolic volume index could be demonstrated; the extent of left ventricular apical and right ventricular wall motion abnormalities, both frequently associated with inferior infarction, did not correlate with the quantity of anterior S-T depression. These data show that anterior S-T segment depression occurs commonly during the early evolution of transmural inferior infarction, is not generally a marker of functionally significant anterior ischemia and cannot be used to predict left ventricular function in individual patients. Anterior S-T segment depression may be determined by reciprocal mechanisms.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cardiac Catheterization
  • Clinical Enzyme Tests
  • Creatine Kinase / blood
  • Electrocardiography*
  • Heart Ventricles / diagnostic imaging
  • Heart Ventricles / physiopathology
  • Humans
  • Isoenzymes
  • Male
  • Middle Aged
  • Myocardial Infarction / diagnosis*
  • Myocardial Infarction / diagnostic imaging
  • Myocardial Infarction / physiopathology
  • Prospective Studies
  • Radionuclide Imaging
  • Sodium Pertechnetate Tc 99m
  • Stroke Volume
  • Technetium

Substances

  • Isoenzymes
  • Technetium
  • Sodium Pertechnetate Tc 99m
  • Creatine Kinase