Compressive mechanical properties of the intraluminal thrombus in abdominal aortic aneurysms and fibrin-based thrombus mimics

John H. Ashton, Jonathan P Vande Geest, Bruce R. Simon, Darren G. Haskett

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

An intraluminal thrombus (ILT) forms in the majority of abdominal aortic aneurysms (AAAs). While the ILT has traditionally been perceived as a byproduct of aneurysmal disease, the mechanical environment within the ILT may contribute to the degeneration of the aortic wall by affecting biological events of cells embedded within the ILT. In this study, the drained secant modulus (E5∼modulus at 5% strain) of ILT specimens (luminal, medial, and abluminal) procured from elective open repair was measured and compared using unconfined compression. Five groups of fibrin-based thrombus mimics were also synthesized by mixing various combinations of fibrinogen, thrombin, and calcium. Drained secant moduli were compared to determine the effect of the components' concentrations on mimic stiffness. The stiffness of mimics was also compared to the native ILT. Preliminary data on the water content of the ILT layers and mimics was measured. It was found that the abluminal layer (E5=19.3 kPa) is stiffer than the medial (2.49 kPa) and luminal (1.54 kPa) layers, both of which are statistically similar. E5 of the mimics (0.63, 0.22, 0.23, 0.87, and 2.54 kPa) is dependent on the concentration of all three components: E5 decreases with a decrease in fibrinogen (60-20 and 20-15 mg/ml) and a decrease in thrombin (3-0.3 units/ml), and E5 increases with a decrease in calcium (0.1-0.01 M). E5 from two of the mimics were not statistically different than the medial and luminal layers of ILT. A thrombus mimic with similar biochemical components, structure, and mechanical properties as native ILT would provide an appropriate test medium for AAA mechanobiology studies.

Original languageEnglish (US)
Pages (from-to)197-201
Number of pages5
JournalJournal of Biomechanics
Volume42
Issue number3
DOIs
StatePublished - Feb 9 2009

Fingerprint

Abdominal Aortic Aneurysm
Fibrin
Calcium
Thrombosis
Stiffness
Mechanical properties
Water content
Byproducts
Repair
Thrombin
Fibrinogen
Biophysics

Keywords

  • AAA
  • Aneurysm
  • Compressive modulus
  • Fibrinogen
  • Intraluminal thrombus

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Rehabilitation
  • Biophysics
  • Biomedical Engineering

Cite this

Compressive mechanical properties of the intraluminal thrombus in abdominal aortic aneurysms and fibrin-based thrombus mimics. / Ashton, John H.; Vande Geest, Jonathan P; Simon, Bruce R.; Haskett, Darren G.

In: Journal of Biomechanics, Vol. 42, No. 3, 09.02.2009, p. 197-201.

Research output: Contribution to journalArticle

@article{a0029df94a5943598982e3a277b98f10,
title = "Compressive mechanical properties of the intraluminal thrombus in abdominal aortic aneurysms and fibrin-based thrombus mimics",
abstract = "An intraluminal thrombus (ILT) forms in the majority of abdominal aortic aneurysms (AAAs). While the ILT has traditionally been perceived as a byproduct of aneurysmal disease, the mechanical environment within the ILT may contribute to the degeneration of the aortic wall by affecting biological events of cells embedded within the ILT. In this study, the drained secant modulus (E5∼modulus at 5{\%} strain) of ILT specimens (luminal, medial, and abluminal) procured from elective open repair was measured and compared using unconfined compression. Five groups of fibrin-based thrombus mimics were also synthesized by mixing various combinations of fibrinogen, thrombin, and calcium. Drained secant moduli were compared to determine the effect of the components' concentrations on mimic stiffness. The stiffness of mimics was also compared to the native ILT. Preliminary data on the water content of the ILT layers and mimics was measured. It was found that the abluminal layer (E5=19.3 kPa) is stiffer than the medial (2.49 kPa) and luminal (1.54 kPa) layers, both of which are statistically similar. E5 of the mimics (0.63, 0.22, 0.23, 0.87, and 2.54 kPa) is dependent on the concentration of all three components: E5 decreases with a decrease in fibrinogen (60-20 and 20-15 mg/ml) and a decrease in thrombin (3-0.3 units/ml), and E5 increases with a decrease in calcium (0.1-0.01 M). E5 from two of the mimics were not statistically different than the medial and luminal layers of ILT. A thrombus mimic with similar biochemical components, structure, and mechanical properties as native ILT would provide an appropriate test medium for AAA mechanobiology studies.",
keywords = "AAA, Aneurysm, Compressive modulus, Fibrinogen, Intraluminal thrombus",
author = "Ashton, {John H.} and {Vande Geest}, {Jonathan P} and Simon, {Bruce R.} and Haskett, {Darren G.}",
year = "2009",
month = "2",
day = "9",
doi = "10.1016/j.jbiomech.2008.10.024",
language = "English (US)",
volume = "42",
pages = "197--201",
journal = "Journal of Biomechanics",
issn = "0021-9290",
publisher = "Elsevier Limited",
number = "3",

}

TY - JOUR

T1 - Compressive mechanical properties of the intraluminal thrombus in abdominal aortic aneurysms and fibrin-based thrombus mimics

AU - Ashton, John H.

AU - Vande Geest, Jonathan P

AU - Simon, Bruce R.

AU - Haskett, Darren G.

PY - 2009/2/9

Y1 - 2009/2/9

N2 - An intraluminal thrombus (ILT) forms in the majority of abdominal aortic aneurysms (AAAs). While the ILT has traditionally been perceived as a byproduct of aneurysmal disease, the mechanical environment within the ILT may contribute to the degeneration of the aortic wall by affecting biological events of cells embedded within the ILT. In this study, the drained secant modulus (E5∼modulus at 5% strain) of ILT specimens (luminal, medial, and abluminal) procured from elective open repair was measured and compared using unconfined compression. Five groups of fibrin-based thrombus mimics were also synthesized by mixing various combinations of fibrinogen, thrombin, and calcium. Drained secant moduli were compared to determine the effect of the components' concentrations on mimic stiffness. The stiffness of mimics was also compared to the native ILT. Preliminary data on the water content of the ILT layers and mimics was measured. It was found that the abluminal layer (E5=19.3 kPa) is stiffer than the medial (2.49 kPa) and luminal (1.54 kPa) layers, both of which are statistically similar. E5 of the mimics (0.63, 0.22, 0.23, 0.87, and 2.54 kPa) is dependent on the concentration of all three components: E5 decreases with a decrease in fibrinogen (60-20 and 20-15 mg/ml) and a decrease in thrombin (3-0.3 units/ml), and E5 increases with a decrease in calcium (0.1-0.01 M). E5 from two of the mimics were not statistically different than the medial and luminal layers of ILT. A thrombus mimic with similar biochemical components, structure, and mechanical properties as native ILT would provide an appropriate test medium for AAA mechanobiology studies.

AB - An intraluminal thrombus (ILT) forms in the majority of abdominal aortic aneurysms (AAAs). While the ILT has traditionally been perceived as a byproduct of aneurysmal disease, the mechanical environment within the ILT may contribute to the degeneration of the aortic wall by affecting biological events of cells embedded within the ILT. In this study, the drained secant modulus (E5∼modulus at 5% strain) of ILT specimens (luminal, medial, and abluminal) procured from elective open repair was measured and compared using unconfined compression. Five groups of fibrin-based thrombus mimics were also synthesized by mixing various combinations of fibrinogen, thrombin, and calcium. Drained secant moduli were compared to determine the effect of the components' concentrations on mimic stiffness. The stiffness of mimics was also compared to the native ILT. Preliminary data on the water content of the ILT layers and mimics was measured. It was found that the abluminal layer (E5=19.3 kPa) is stiffer than the medial (2.49 kPa) and luminal (1.54 kPa) layers, both of which are statistically similar. E5 of the mimics (0.63, 0.22, 0.23, 0.87, and 2.54 kPa) is dependent on the concentration of all three components: E5 decreases with a decrease in fibrinogen (60-20 and 20-15 mg/ml) and a decrease in thrombin (3-0.3 units/ml), and E5 increases with a decrease in calcium (0.1-0.01 M). E5 from two of the mimics were not statistically different than the medial and luminal layers of ILT. A thrombus mimic with similar biochemical components, structure, and mechanical properties as native ILT would provide an appropriate test medium for AAA mechanobiology studies.

KW - AAA

KW - Aneurysm

KW - Compressive modulus

KW - Fibrinogen

KW - Intraluminal thrombus

UR - http://www.scopus.com/inward/record.url?scp=58649083002&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=58649083002&partnerID=8YFLogxK

U2 - 10.1016/j.jbiomech.2008.10.024

DO - 10.1016/j.jbiomech.2008.10.024

M3 - Article

C2 - 19058807

AN - SCOPUS:58649083002

VL - 42

SP - 197

EP - 201

JO - Journal of Biomechanics

JF - Journal of Biomechanics

SN - 0021-9290

IS - 3

ER -