Exercise-induced ST-elevation is related to left ventricular dysfunction but not to myocardial viability in patients with healed myocardial infarction

Eur J Heart Fail. 2001 Dec;3(6):709-16. doi: 10.1016/s1388-9842(01)00186-6.

Abstract

Background: Exercise-induced ST-segment elevation was proposed as a marker of myocardial viability after a recent myocardial infarction.

Aims: The aim of this study was to evaluate whether exercise-induced ST segment elevation is related to viability or to left ventricular dysfunction in patients with history of old Q wave myocardial infarction.

Methods: Fifty patients (43 men, age 57+/-11 years) were studied 31+/-49 months after a Q wave myocardial infarction. They all underwent stress, reinjection-redistribution, and late redistribution Tl-201 SPECT, completed by equilibrium radionuclide angiography. Viability was defined by defect reversibility or significant (>60%) persistent Tl-201 uptake in dyssinergic segments on late redistribution SPECT. Relative post-exercise and reinjection-redistribution LV volumes were calculated using validated software (QGS).

Results: Twenty-one out of 50 patients (42%, G1) had significant stress-induced ST-elevation (>1 mm 80 ms after J point in at least 2 ECG leads with Q wave), and 29/50 (58%, G2) did not. Seventeen out of 50 patients (34%) demonstrated myocardial viability on late redistribution scan. The diagnostic accuracy of exercise-induced ST-elevation was only 52% for viability assessment. Significant LVEF reduction and increased relative LV volumes were observed in G1 compared to G2 (LVEF: 39+/-10% vs. 49+/-11%, P=0.003; post-stress LV volume: 134+/-98 ml vs. 81+/-41 ml, P<0.02; reinjection-redistribution LV volume: 123+/-86 ml vs. 79+/-40 ml; P<0.02). Perfusion defects were similar in G1 and G2 (post-exercise: 38+/-12% vs. 37+/-14%, ns; reinjection-redistribution: 31+/-11% vs. 30+/-11%, ns; late redistribution: 30+/-10% vs. 28+/-11%, ns).

Conclusion: These results suggest that, in patients with history of myocardial infarction, exercise-induced ST-segment elevation is not related to persistent myocardial viability but is associated to left ventricular dysfunction.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Aged
  • Analysis of Variance
  • Dyskinesias / complications
  • Dyskinesias / diagnostic imaging
  • Electrocardiography, Ambulatory*
  • Exercise Test
  • Exercise*
  • Female
  • Fetal Viability / physiology*
  • France
  • Heart Rate / physiology
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / complications
  • Myocardial Infarction / diagnostic imaging
  • Myocardial Infarction / physiopathology*
  • Perfusion
  • Predictive Value of Tests
  • Radionuclide Angiography
  • Sensitivity and Specificity
  • Stroke Volume / physiology
  • Thallium Radioisotopes
  • Ventricular Dysfunction, Left / complications
  • Ventricular Dysfunction, Left / diagnostic imaging
  • Ventricular Dysfunction, Left / physiopathology*

Substances

  • Thallium Radioisotopes