Dobutamine-induced ST-segment elevation in patients with acute myocardial infarction and the role of myocardial ischemia, viability, and ventricular dyssynergy.
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.
Ricci
R
R
Division of Cardiology, S. Spirito Hospital, Rome, Italy.
Bigi
R
R
Galati
A
A
Bandini
P
P
Coletta
C
C
Fiorentini
C
C
Lumia
F
F
Occhi
G
G
Ceci
V
V
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002316:Cardiotonic Agents / Q000008:administration & dosage; D004280:Dobutamine / Q000008:administration & dosage; D004452:Echocardiography / Q000187:drug effects / Q000379:methods / Q000706:statistics & numerical data; D004562:Electrocardiography / Q000187:drug effects* / Q000379:methods / Q000706:statistics & numerical data; D005080:Exercise Test / Q000187:drug effects / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis*; D017202:Myocardial Ischemia / Q000175:diagnosis*; D015588:Observer Variation; D012680:Sensitivity and Specificity; D018754:Ventricular Dysfunction / Q000175:diagnosis*
D002316:Cardiotonic Agents; D004280:Dobutamine