Relation of coronary blood flow and reactive hyperemia to regional dysfunction induced by dopamine infusion in dogs: Limitations in detecting subcritical coronary stenoses
In: Journal of the American College of Cardiology, Jg. 5 (1985-03-01), Heft 3, S. 664-671
Online
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Zugriff:
Sympathomimetic agents have been used clinically to elicit regional dysfunction or heterogeneity of coronary blood flow to detect coronary artery lesions. However, the usefulness of this procedure in detecting mild to moderate coronary stenoses has not been defined previously. This was investigated in 10 open chest anesthetized dogs using subendocardial ultrasonic crystals to measure segment lengths. An electromagnetic flow probe was placed on the proximal left anterior descending artery, and graded coronary stenoses were created using a cuff occluder. In the first phase of the study, subcritical coronary stenoses were created which impaired maximal postocclusion reactive hyperemia, but not coronary blood flow at rest. A constant infusion of dopamine (average 15 μg/kg per min) was then administered. Regional dysfunction during dopamine infusion was not consistently observed despite production of coronary stenoses resulting in total loss of reactive hyperemia at rest. Regional function during dopamine treatment was, however, critically related to the actual changes in coronary blood flow during the infusion. In the second phase of the study, regional function during dopamine challenge was investigated during progressive impairments of coronary blood flow. Regional function was maintained until coronary blood flow during the infusion was reduced to near rest levels below which regional function deteriorated rapidly. It is concluded that: 1) dopamine infusion is insensitive for the detection of mild to moderate coronary stenoses defined on the basis of subcritical impairments of coronary blood flow reserve; 2) regional function during dopamine infusion is maintained provided that coronary blood flow is maintained at or above rest levels; and 3) measurement of coronary flow reserve at rest is more sensitive for the detection of coronary stenoses than is induction of regional dysfunction during dopamine infusion.
Titel: |
Relation of coronary blood flow and reactive hyperemia to regional dysfunction induced by dopamine infusion in dogs: Limitations in detecting subcritical coronary stenoses
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Autor/in / Beteiligte Person: | John McB. Hodgson ; G.B. John Mancini |
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Zeitschrift: | Journal of the American College of Cardiology, Jg. 5 (1985-03-01), Heft 3, S. 664-671 |
Veröffentlichung: | Elsevier BV, 1985 |
Medientyp: | unknown |
ISSN: | 0735-1097 (print) |
DOI: | 10.1016/s0735-1097(85)80392-2 |
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