Right ventricular oxygen supply/demand balance in exercising dogs.

@article{Hart2001RightVO,
  title={Right ventricular oxygen supply/demand balance in exercising dogs.},
  author={Bradley J. Hart and X Bian and Patricia A. Gwirtz and Srinath Setty and H. Fred Downey},
  journal={American journal of physiology. Heart and circulatory physiology},
  year={2001},
  volume={281 2},
  pages={
          H823-30
        }
}
  • B. Hart, X. Bian, +2 authors H. F. Downey
  • Published 1 August 2001
  • Medicine
  • American journal of physiology. Heart and circulatory physiology
This is the first investigation of right ventricular (RV) myocardial oxygen supply/demand balance in a conscious animal. A novel technique developed in our laboratory was used to collect right coronary (RC) venous blood samples from seven instrumented, conscious dogs at rest and during graded treadmill exercise. Contributions of the RV oxygen extraction reserve and the RC flow reserve to exercise-induced increases in RV oxygen demand were measured. Strenuous exercise caused a 269% increase in… 
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40 Citations
Highly Influential Citations
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Background Citations
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Methods Citations
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Results Citations
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40 Citations

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Citation Type

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The coronary collateral system embodies a dynamic network of interarterial vessels that can undergo both long- and short-term adjustments that can modulate blood flow to the dependent myocardium, and training augments endothelium-dependent vasodilation throughout the coronary microcirculation.
α-Adrenergic Vasoconstrictor Tone Limits Right Coronary Blood Flow in Exercising Dogs
In exercising dogs, increased myocardial O2 consumption (MVO2) of the left ventricle is met primarily by hyperemia, whereas increased O2 extraction makes a greater contribution to right ventricular…
Mechanisms of increased right and left ventricular oxygen uptake during inotropic stimulation.
Right Ventricular Oxygen Delivery as a Determinant of Right Ventricular Functional Reserve during Exercise in Juvenile Swine with Chronic Pulmonary Hypertension.
TLDR
The inability to sufficiently increase RV-O2supply to meet the increased O2demand during exercise is principally due to the reduced RV-perfusion relative to healthy control values and likely contributes to impaired RV-contractile function and thereby to the limited exercise capacity that is commonly observed in patients with PH.
Adaptations in the balance between coronary blood flow and myocardial metabolism in endurance athletes
  • J. Tune
  • Biology, Medicine
    The Journal of physiology
  • 2008
TLDR
The authors suggest that the degree of adenosine-induced vasodilatation declined as the level of fitness increased; however, this trend is probably related to the decrease in myocardial perfusion per gram of tissue as absolute changes in flow from baseline were similar between groups.
Supine-exercise-induced oxygen supply to the right myocardium is attenuated in patients with severe idiopathic pulmonary arterial hypertension
TLDR
H-O EF patients were hemodynamically poorer and showed a lower exercise-induced MBF increase compared to L-OEF patients, suggesting exercise- induced O2 supply limitation.
Right ventricular oxygen supply parameters are decreased in human and experimental pulmonary hypertension.
Nitric oxide contributes to right coronary vasodilation during systemic hypoxia.
TLDR
It is concluded that NO contributes to RC vasodilation during systemic hypoxia, and increases in RV MVo(2) during Hypoxia are met normally by increasing RC blood flow.
Mechanisms of Oxygen Demand/Supply Balance in the Right Ventricle
TLDR
Normal right ventricular external work and O2 demand/supply balance can be maintained during moderate coronary hypoperfusion, especially during poorly autoregulating right coronary circulation.
Endogenous nitric oxide regulates right coronary blood flow during acute pulmonary hypertension in conscious dogs
TLDR
No is required for the RC hyperemic response to acute pulmonary hypertension as well as for normal resting RC blood flow after blockade of NO synthesis, RV O 2 supply at rest and during pulmonary hypertension was sustained by increased RV O2 extraction.
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References

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TLDR
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TLDR
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TLDR
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