Abstract
Transmural variations in the relationship between structural and fluid transport properties of myocardial capillary networks are determined via continuum modeling approaches using recent three-dimensional (3D) data on the microvascular structure. Specifically, the permeability tensor, which quantifies the inverse of the blood flow resistivity of the capillary network, is computed by volume-averaging flow solutions in synthetic networks with geometrical and topological properties derived from an anatomically-detailed microvascular data set extracted from the rat myocardium. Results show that the permeability is approximately ten times higher in the principal direction of capillary alignment (the "longitudinal" direction) than perpendicular to this direction, reflecting the strong anisotropy of the microvascular network. Additionally, a 30% increase in capillary diameter from subepicardium to subendocardium is shown to translate to a 130% transmural rise in permeability in the longitudinal capillary direction. This result supports the hypothesis that perfusion is preferentially facilitated during diastole in the subendocardial microvasculature to compensate for the severely-reduced systolic perfusion in the subendocardium.
Original language | English (US) |
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Pages (from-to) | 1966-1977 |
Number of pages | 12 |
Journal | Annals of Biomedical Engineering |
Volume | 42 |
Issue number | 9 |
DOIs | |
State | Published - May 28 2014 |
Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): KUK-C1-013-04
Acknowledgements: The authors acknowledge support from the Virtual Physiological Rat Project (NIH1 P50 GM094503-1), the EPSRC (Engineering and Physical Sciences Research Council) under grant numbers EP/F043929/1 and EP/G007527/2, and Award No. KUK-C1-013-04 made by King Abdullah University of Science and Technology (KAUST). The authors would also like to thank Prof. Timothy W. Secomb (University of Arizona) for helpful scientific discussions.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.