How cardiac contraction affects the coronary vasculature.
We modeled the influence of cardiac contraction on maximally dilated coronary blood vessels, whether single or in juxtaposition, taking into account the nonlinear material properties of both the vascular wall and the myocardium. We calculated pressure-area relations of single, embedded coronary blood vessels, and used these relations to calculate diastolic and systolic coronary pressure-flow relations in a model of the coronary vasculature. The model shows that the change in myocardial material properties during contraction can explain the decrease in coronary vessel area and coronary flow generally observed in experiments. The model also shows that arterioles can be protected from the compressive action of the cardiac muscle by the presence of accompanying venules, which is favorable for coronary blood flow.
Westerhof
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Laboratory for Physiology, Institute for Cardiovascular Research (ICaR-VU), Amsterdam, The Netherlands.
Sipkema
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Vis
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MA
D000818:Animals; D001160:Arterioles / Q000033:anatomy & histology / Q000502:physiology; D001783:Blood Flow Velocity; D001794:Blood Pressure; D003331:Coronary Vessels / Q000033:anatomy & histology / Q000502:physiology*; D003971:Diastole; D009200:Myocardial Contraction / Q000502:physiology*; D013599:Systole; D014699:Venules / Q000033:anatomy & histology / Q000502:physiology