Effect of dobutamine on left ventricular functional geometry after acute myocardial infarction: experimental study.
BACKGROUND
Acute myocardial infarction causes left ventricular (LV) remodelling, which forms the substrate for its early and late complications. The aim of this experimental study was to evaluate the acute changes in LV functional geometry after acute myocardial infarction using echocardiography and to investigate the effect of continuous intravenous dobutamine administration on those changes.


METHODS
In 22 pigs acute myocardial infarction was induced by ligation of the anterior descending branch of the left coronary artery. In 11 animals dobutamine was administered at a rate of 5 microg/kg/min (Group B), while the remainder (Group A) served as controls. Before infarction and 5, 15, 45 and 75 minutes after, the fractional shortening of the long (FSL) and short (FSS) axes of the LV were measured echocardiographically and the ejection fraction (EF) was calculated.


RESULTS
In Group A FSL and EF reduced significantly after infarction (p < 0.0001), while FSS increased significantly (p < 0.05). In Group B FSL and EF reduced significantly 5 minutes after infarction and then returned progressively to normal values after 15 min (EF) and 45 min (FSL). FSS did not change significantly during 75 minutes after infarction.


CONCLUSIONS
Dobutamine, administered at a rate of 5 microg/kg/min during acute experimental anterior myocardial infarction, before the appearance of early complications, may prevent the acute, unfavourable remodelling of the LV, as manifested by a decrease in FSL and EF and a compensatory increase in FSS.
Saridakis
Nikolaos S
NS
Department of Clinical Therapeutics, Athens University Medical School, "Alexandra" Hospital, Athens, Greece.
Toumanidis
Savvas T
ST
Vintzileou
Anastasia M
AM
Tsirikos
Nikolaos
N
Haniotis
Demetrios
D
Kottis
Georgios
G
Kalantaridou
Anna
A
Stamatelopoulos
Stamatios F
SF
Moulopoulos
Spyridon D
SD
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology*; D003331:Coronary Vessels / Q000503:physiopathology / Q000601:surgery; D004195:Disease Models, Animal; D004280:Dobutamine / Q000494:pharmacology*; D004452:Echocardiography; D007091:Image Processing, Computer-Assisted; D007262:Infusions, Intravenous; D008026:Ligation / Q000009:adverse effects; D009200:Myocardial Contraction / Q000187:drug effects; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology*; D012107:Research Design; D013318:Stroke Volume / Q000187:drug effects; D013552:Swine; D013997:Time Factors; D014655:Vascular Resistance / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects*; D020257:Ventricular Remodeling / Q000187:drug effects
D000318:Adrenergic beta-Agonists; D002316:Cardiotonic Agents; D004280:Dobutamine