Significance of T wave normalization in the electrocardiogram during exercise stress test

Am Heart J. 1987 Dec;114(6):1342-8. doi: 10.1016/0002-8703(87)90535-7.

Abstract

Although normalization of previously inverted T waves in the ECG is not uncommon during exercise treadmill testing, the clinical significance of this finding is still unclear. This was investigated in 45 patients during thallium-201 exercise testing. Patients with secondary T wave abnormalities on the resting ECG and ischemic exercise ST segment depression were excluded. On the thallium-201 scans, the left ventricle was divided into anterior-septal and inferior-posterior segments; these were considered equivalent to T wave changes in leads V1 and V5, and aVF, respectively. A positive thallium-201 scan was found in 43 of 45 (95%) patients and in 49 of 52 (94%) cardiac segments that showed T wave normalization. When thallium scans and T wave changes were matched to sites of involvement, 76% of T wave normalization in lead aV, was associated with positive thallium scans in the inferior-posterior segments, and 77% of T wave normalization in V1 and V5 was associated with positive thallium scans in the anterior-septal segments. These site correlations were similar for reversible and fixed thallium defects, and for patients not on digoxin therapy. Similar correlations were noted for the sites of T wave changes and coronary artery lesions in 12 patients who had angiography. In patients with a high prevalence for coronary artery disease, exercise T wave normalization is highly specific for the presence of the disease. In addition, it represents predominantly either previous injury or exercise-induced ischemic changes over the site of ECG involvement, rather than reciprocal changes of the opposite ventricular wall.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Cardiac Catheterization
  • Coronary Angiography
  • Coronary Disease / physiopathology*
  • Electrocardiography*
  • Exercise Test
  • Heart / diagnostic imaging*
  • Humans
  • Image Interpretation, Computer-Assisted
  • Male
  • Middle Aged
  • Radionuclide Imaging
  • Thallium Radioisotopes

Substances

  • Thallium Radioisotopes