TY - JOUR
T1 - Effects of dobutamine on myocardial blood flow, contractile function, and bioenergetic responses distal to coronary stenosis
T2 - Implications with regard to dobutamine stress testing
AU - Zhang, Jianyi
AU - Path, Greg
AU - Chepuri, Vanaya
AU - Homans, David C.
AU - Merkle, Hellmut
AU - Hendrich, Kristy
AU - Uǧurbil, Kâmil
AU - Bache, Robert J.
AU - From, Arthur H.L.
N1 - Funding Information:
This work was supported by U. S. Public Health Service grants HL33600, HL32427, and HL21872; a research fellowship (J. Z.); and Grant-in-Aid from the Minnesota Affiliate of the American Heart Association and Department of Veterans Affairs Medical Research Funds.
PY - 1995/2
Y1 - 1995/2
N2 - To determine the effects of dobutamine stimulation on myocardium distal to a coronary stenosis, transmural spatially localized phosphorus 31 nuclear magnetic resonance measurements of myocardial high-energy phosphate compounds (adenosine triphosphate and phosphocreatine), inorganic phosphate, and blood flow and systolic wall thickening were made in 8 open-chested dogs. Data were collected under (1) control conditions, (2) after the application of a moderate coronary stenosis, (3) during infusion of dobutamine with continuing stenosis, and (4) after the release of the stenosis with continuing dobutamine. Stenosis was associated with concordant reductions of subendocardial blood flow, wall thickening, and high-energy phosphate, and mild elevation of inorganic phosphate; subepicardial measurements were essentially unchanged. During dobutamine infusion, blood flow increased in all myocardial layers. Wall thickening returned to control values in the subendocardium and increased nonsignificantly in the subepicardium. Additional loss of high-energy phosphate occured only in the subepicardium. The data suggest that improved contractile function associated with dobutamine infusion resulted from the inotropic effects of dobutamine and was made possible by the improved blood flow it produced. The data indicate that measurements of blood flow and contractile function do not reliably predict the transmural myocardial metabolic responses to inotropic perturbations in the hypoperfused heart. Taken together, the present findings yield insights with regard to the interpretation of diagnostic dobutamine stimulation testing with single photon emission tomography, radionuclide angiography, and echocardiography.
AB - To determine the effects of dobutamine stimulation on myocardium distal to a coronary stenosis, transmural spatially localized phosphorus 31 nuclear magnetic resonance measurements of myocardial high-energy phosphate compounds (adenosine triphosphate and phosphocreatine), inorganic phosphate, and blood flow and systolic wall thickening were made in 8 open-chested dogs. Data were collected under (1) control conditions, (2) after the application of a moderate coronary stenosis, (3) during infusion of dobutamine with continuing stenosis, and (4) after the release of the stenosis with continuing dobutamine. Stenosis was associated with concordant reductions of subendocardial blood flow, wall thickening, and high-energy phosphate, and mild elevation of inorganic phosphate; subepicardial measurements were essentially unchanged. During dobutamine infusion, blood flow increased in all myocardial layers. Wall thickening returned to control values in the subendocardium and increased nonsignificantly in the subepicardium. Additional loss of high-energy phosphate occured only in the subepicardium. The data suggest that improved contractile function associated with dobutamine infusion resulted from the inotropic effects of dobutamine and was made possible by the improved blood flow it produced. The data indicate that measurements of blood flow and contractile function do not reliably predict the transmural myocardial metabolic responses to inotropic perturbations in the hypoperfused heart. Taken together, the present findings yield insights with regard to the interpretation of diagnostic dobutamine stimulation testing with single photon emission tomography, radionuclide angiography, and echocardiography.
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U2 - 10.1016/0002-8703(95)90016-0
DO - 10.1016/0002-8703(95)90016-0
M3 - Article
C2 - 7832107
AN - SCOPUS:0028908823
SN - 0002-8703
VL - 129
SP - 330
EP - 342
JO - American Heart Journal
JF - American Heart Journal
IS - 2
ER -