title: Low-dose dobutamine in patients with acute myocardial infarction identifies viable but not contractile myocardium and predicts the magnitude of improvement in wall motion abnormalities in response to coronary revascularization.
abstract: To assess the effects of coronary revascularization on viable but noncontractile myocardium, we examined 21 patients with a documented anterior acute myocardial infarction who had a significant improvement in wall motion abnormality evaluated by two-dimensional echocardiography in the infarct-related artery in response to low-dose dobutamine infusion. All patients had a significant residual stenosis in the infarct-related artery. In response to low-dose dobutamine, there was a marked improvement in contractility in the infarct-related area segments and this was reflected by a decrease in echocardiographic score index from 1.5 +/- 0.15 to 1.09 +/- 0.08 (p = 0.0001). Of these 21 patients, 13 underwent successful revascularization: 10 had percutaneous transluminal coronary angioplasty (PTCA) and three had coronary artery bypass grafts (CABG) (group I). Eight patients received medical therapy only (group II). At 40 +/- 15 days of follow-up, both groups had improvement in their segmental wall motion abnormalities. However, the improvement in group I was greater than that in group II, 1.1 +/- 0.13 and 1.35 +/- 0.1, respectively (p = 0.0002). We conclude that: (1) low-dose dobutamine infusion may identify viable but noncontractile myocardium in patients with acute myocardial infarction and (2) in these patients revascularization causes a greater improvement in left ventricular function over time when compared with a nonrevascularized group.
authors.affiliation: Heart and Vascular Institute, Division of Cardiovascular Medicine, Henry Ford Hospital, Detroit, MI 48202.
authors.forename: F
authors.initials: F
authors.lastname: Barilla
authors.forename: M
authors.initials: M
authors.lastname: Gheorghiade
authors.forename: M
authors.initials: M
authors.lastname: Alam
authors.forename: F
authors.initials: F
authors.lastname: Khaja
authors.forename: S
authors.initials: S
authors.lastname: Goldstein
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D004280:Dobutamine / Q000008:administration & dosage; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects*; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000628:therapy; D015425:Myocardial Reperfusion; D011379:Prognosis; D012074:Remission Induction
chemical_list: D004280:Dobutamine