Failure of the porcine ascending aorta

Multidirectional experiments and a unifying microstructural model

Colleen M. Witzenburg, Rohit Y. Dhume, Sachin B. Shah, Christopher E. Korenczuk, Hallie P. Wagner, Patrick W Alford, Victor H Barocas

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The ascending thoracic aorta is poorly understood mechanically, especially its risk of dissection. To make better predictions of dissection risk, more information about the multidimensional failure behavior of the tissue is needed, and this information must be incorporated into an appropriate theoretical/computational model. Toward the creation of such a model, uniaxial, equibiaxial, peel, and shear lap tests were performed on healthy porcine ascending aorta samples. Uniaxial and equibiaxial tests showed anisotropy with greater stiffness and strength in the circumferential direction. Shear lap tests showed catastrophic failure at shear stresses (150-200 kPa) much lower than uniaxial tests (750-2500 kPa), consistent with the low peel tension (60 mN/mm). A novel multiscale computational model, including both prefailure and failure mechanics of the aorta, was developed. The microstructural part of the model included contributions from a collagenreinforced elastin sheet and interlamellar connections representing fibrillin and smooth muscle. Components were represented as nonlinear fibers that failed at a critical stretch. Multiscale simulations of the different experiments were performed, and the model, appropriately specified, agreed well with all experimental data, representing a uniquely complete structure-based description of aorta mechanics. In addition, our experiments and model demonstrate the very low strength of the aorta in radial shear, suggesting an important possible mechanism for aortic dissection.

Original languageEnglish (US)
Article number031005
JournalJournal of Biomechanical Engineering
Volume139
Issue number3
DOIs
StatePublished - Mar 1 2017

Fingerprint

Aorta
Swine
Dissection
Mechanics
Experiments
Elastin
Anisotropy
Thoracic Aorta
Smooth Muscle
Theoretical Models
Muscle
Shear stress
Stiffness
Tissue
Fibers

Keywords

  • Biomechanics
  • Failure
  • Peel
  • Shear

Cite this

Failure of the porcine ascending aorta : Multidirectional experiments and a unifying microstructural model. / Witzenburg, Colleen M.; Dhume, Rohit Y.; Shah, Sachin B.; Korenczuk, Christopher E.; Wagner, Hallie P.; Alford, Patrick W; Barocas, Victor H.

In: Journal of Biomechanical Engineering, Vol. 139, No. 3, 031005, 01.03.2017.

Research output: Contribution to journalArticle

Witzenburg, Colleen M. ; Dhume, Rohit Y. ; Shah, Sachin B. ; Korenczuk, Christopher E. ; Wagner, Hallie P. ; Alford, Patrick W ; Barocas, Victor H. / Failure of the porcine ascending aorta : Multidirectional experiments and a unifying microstructural model. In: Journal of Biomechanical Engineering. 2017 ; Vol. 139, No. 3.
@article{71721b711da346f2a4ba50534725a200,
title = "Failure of the porcine ascending aorta: Multidirectional experiments and a unifying microstructural model",
abstract = "The ascending thoracic aorta is poorly understood mechanically, especially its risk of dissection. To make better predictions of dissection risk, more information about the multidimensional failure behavior of the tissue is needed, and this information must be incorporated into an appropriate theoretical/computational model. Toward the creation of such a model, uniaxial, equibiaxial, peel, and shear lap tests were performed on healthy porcine ascending aorta samples. Uniaxial and equibiaxial tests showed anisotropy with greater stiffness and strength in the circumferential direction. Shear lap tests showed catastrophic failure at shear stresses (150-200 kPa) much lower than uniaxial tests (750-2500 kPa), consistent with the low peel tension (60 mN/mm). A novel multiscale computational model, including both prefailure and failure mechanics of the aorta, was developed. The microstructural part of the model included contributions from a collagenreinforced elastin sheet and interlamellar connections representing fibrillin and smooth muscle. Components were represented as nonlinear fibers that failed at a critical stretch. Multiscale simulations of the different experiments were performed, and the model, appropriately specified, agreed well with all experimental data, representing a uniquely complete structure-based description of aorta mechanics. In addition, our experiments and model demonstrate the very low strength of the aorta in radial shear, suggesting an important possible mechanism for aortic dissection.",
keywords = "Biomechanics, Failure, Peel, Shear",
author = "Witzenburg, {Colleen M.} and Dhume, {Rohit Y.} and Shah, {Sachin B.} and Korenczuk, {Christopher E.} and Wagner, {Hallie P.} and Alford, {Patrick W} and Barocas, {Victor H}",
year = "2017",
month = "3",
day = "1",
doi = "10.1115/1.4035264",
language = "English (US)",
volume = "139",
journal = "Journal of Biomechanical Engineering",
issn = "0148-0731",
publisher = "American Society of Mechanical Engineers(ASME)",
number = "3",

}

TY - JOUR

T1 - Failure of the porcine ascending aorta

T2 - Multidirectional experiments and a unifying microstructural model

AU - Witzenburg, Colleen M.

AU - Dhume, Rohit Y.

AU - Shah, Sachin B.

AU - Korenczuk, Christopher E.

AU - Wagner, Hallie P.

AU - Alford, Patrick W

AU - Barocas, Victor H

PY - 2017/3/1

Y1 - 2017/3/1

N2 - The ascending thoracic aorta is poorly understood mechanically, especially its risk of dissection. To make better predictions of dissection risk, more information about the multidimensional failure behavior of the tissue is needed, and this information must be incorporated into an appropriate theoretical/computational model. Toward the creation of such a model, uniaxial, equibiaxial, peel, and shear lap tests were performed on healthy porcine ascending aorta samples. Uniaxial and equibiaxial tests showed anisotropy with greater stiffness and strength in the circumferential direction. Shear lap tests showed catastrophic failure at shear stresses (150-200 kPa) much lower than uniaxial tests (750-2500 kPa), consistent with the low peel tension (60 mN/mm). A novel multiscale computational model, including both prefailure and failure mechanics of the aorta, was developed. The microstructural part of the model included contributions from a collagenreinforced elastin sheet and interlamellar connections representing fibrillin and smooth muscle. Components were represented as nonlinear fibers that failed at a critical stretch. Multiscale simulations of the different experiments were performed, and the model, appropriately specified, agreed well with all experimental data, representing a uniquely complete structure-based description of aorta mechanics. In addition, our experiments and model demonstrate the very low strength of the aorta in radial shear, suggesting an important possible mechanism for aortic dissection.

AB - The ascending thoracic aorta is poorly understood mechanically, especially its risk of dissection. To make better predictions of dissection risk, more information about the multidimensional failure behavior of the tissue is needed, and this information must be incorporated into an appropriate theoretical/computational model. Toward the creation of such a model, uniaxial, equibiaxial, peel, and shear lap tests were performed on healthy porcine ascending aorta samples. Uniaxial and equibiaxial tests showed anisotropy with greater stiffness and strength in the circumferential direction. Shear lap tests showed catastrophic failure at shear stresses (150-200 kPa) much lower than uniaxial tests (750-2500 kPa), consistent with the low peel tension (60 mN/mm). A novel multiscale computational model, including both prefailure and failure mechanics of the aorta, was developed. The microstructural part of the model included contributions from a collagenreinforced elastin sheet and interlamellar connections representing fibrillin and smooth muscle. Components were represented as nonlinear fibers that failed at a critical stretch. Multiscale simulations of the different experiments were performed, and the model, appropriately specified, agreed well with all experimental data, representing a uniquely complete structure-based description of aorta mechanics. In addition, our experiments and model demonstrate the very low strength of the aorta in radial shear, suggesting an important possible mechanism for aortic dissection.

KW - Biomechanics

KW - Failure

KW - Peel

KW - Shear

UR - http://www.scopus.com/inward/record.url?scp=85010285159&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85010285159&partnerID=8YFLogxK

U2 - 10.1115/1.4035264

DO - 10.1115/1.4035264

M3 - Article

VL - 139

JO - Journal of Biomechanical Engineering

JF - Journal of Biomechanical Engineering

SN - 0148-0731

IS - 3

M1 - 031005

ER -