Effect of dobutamine of ventriculoarterial coupling in acute regional myocardial ischemia in dogs.
We assessed the effect of dobutamine on left ventricoarterial coupling during acute regional ischemia. Using a conductance catheter, we analyzed the end-systolic pressure-volume relation (ESPVR) in anesthetized dogs. We calculated the slope of ESPVR (Ees), the slope of the end-systolic pressure-stroke volume relation (Ea), (Ea/Ees) and the ratio (work efficiency) of external work to pressure-volume area at base-line during ischemia induced by occlusion of the left anterior descending coronary artery and during low-dose (1-3 micrograms.min-1.kg-1) and high-dose (4-10 micrograms.min-1.kg-1)dobutamine infusions with ischemia. ESPVR shifted to the right without a change in Ees during ischemia. Dobutamine caused dose-dependent increases in Ees but did not affect the intercept of ESPVR. During ischemia, Ea/Ees increased and work efficiency decreased. Low-dose dobutamine was associated with a return in control for Ea/Ees and work efficiency. High-dose dobutamine increased Ees and Ea but produced no further increase in Ea/Ees or work efficiency. Low-dose dobutamine would appear to be the preferable regimen to achieve the optimal ventriculoarterial coupling in acute regional ischemia associated with mismatched ventriculoarterial coupling and depressed left ventricular work efficiency.
Seki
H
H
Second Department of Internal Medicine, Yamaguchi University School of Medicine, Japan.
Katayama
K
K
Sakai
H
H
Yonezawa
T
T
Kunichika
H
H
Saeki
Y
Y
Hiro
T
T
Matsuzaki
M
M
D000208:Acute Disease; D000818:Animals; D001158:Arteries / Q000187:drug effects / Q000502:physiology; D003331:Coronary Vessels / Q000187:drug effects / Q000502:physiology*; D004280:Dobutamine / Q000494:pharmacology*; D004285:Dogs; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D017202:Myocardial Ischemia / Q000503:physiopathology*; D016276:Ventricular Function / Q000187:drug effects*
D004280:Dobutamine