Dobutamine-induced ST-segment elevation in patients with acute myocardial infarction and the role of myocardial ischemia, viability, and ventricular dyssynergy

Am J Cardiol. 1997 Mar 15;79(6):733-7. doi: 10.1016/s0002-9149(96)00859-4.

Abstract

We analyzed the relation between dobutamine-induced Q-wave ST-segment elevation and regional contraction during low (5 to 10 microg/kg/min) and high doses (20 to 40 microg/kg/min) of dobutamine in a series of 391 dobutamine echocardiographic tests performed 10 +/- 2 days after a first uncomplicated acute myocardial infarction (AMI). ST-segment elevation was defined as > or = 1 mm new or additional J-point elevation with a horizontal or upsloping ST segment lasting 80 ms. Wall motion score index at rest was derived using a 16 segment-4 grade score model. Patients with dobutamine-induced ST-segment elevation had a higher wall motion score index at rest (anterior wall AMI: 1.67 +/- 0.27 vs 1.43 +/- 0.30, p = 0.0001; inferior wall AMI: 1.44 +/- 0.27 vs 1.30 +/- 0.18, p = 0.0001) and similar incidence and extent of myocardial viability and homozonal ischemia in comparison with those without ST-segment elevation. The sensitivity, specificity, and accuracy of dobutamine-induced ST-segment elevation for detecting residual homozonal ischemia were 51%, 55%, and 54%, respectively, in patients with anterior wall AMI, and 42%, 68%, and 58%, respectively, in patients with inferior wall AMI. In conclusion, dobutamine-induced ST-segment elevation is not associated with higher incidence and extent of viable or jeopardized myocardium but rather to a greater extent of wall motion abnormalities at rest. Thus, this finding does not represent a clinically reliable discriminator for selecting patients for coronary angiography and possible revascularization procedures.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cardiotonic Agents* / administration & dosage
  • Dobutamine* / administration & dosage
  • Echocardiography / drug effects
  • Echocardiography / methods
  • Echocardiography / statistics & numerical data
  • Electrocardiography / drug effects*
  • Electrocardiography / methods
  • Electrocardiography / statistics & numerical data
  • Exercise Test / drug effects
  • Exercise Test / methods
  • Exercise Test / statistics & numerical data
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myocardial Infarction / diagnosis*
  • Myocardial Ischemia / diagnosis*
  • Observer Variation
  • Sensitivity and Specificity
  • Ventricular Dysfunction / diagnosis*

Substances

  • Cardiotonic Agents
  • Dobutamine