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Transmural variation and anisotropy of microvascular flow conductivity in the rat myocardium.

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.

SUBMITTER: Smith AF

PROVIDER: S-EPMC4404518 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Transmural variation and anisotropy of microvascular flow conductivity in the rat myocardium.

Smith Amy F AF Shipley Rebecca J RJ Lee Jack J Sands Gregory B GB LeGrice Ian J IJ Smith Nicolas P NP

Annals of biomedical engineering 20140528 9

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 ...[more]

PMID: 24866569

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Dataset Information

Transmural variation and anisotropy of microvascular flow conductivity in the rat myocardium.

Publications

Transmural variation and anisotropy of microvascular flow conductivity in the rat myocardium.

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