Determination of coefficient of friction for self-expanding stent-grafts

Siddharth Vad, Amanda Eskinazi, Timothy Corbett, Tim McGloughlin, Jonathan P Vande Geest

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Migration of stent-grafts (SGs) after endovascular aneurysm repair of abdominal aortic aneurysms is a serious complication that may require secondary intervention. Experimental, analytical, and computational studies have been carried out in the past to understand the factors responsible for migration. In an experimental setting, it can be very challenging to correctly capture and understand the interaction between a SG and an artery. Quantities such as coefficient of friction (COF) and contact pressures that characterize this interaction are difficult to measure using an experimental approach. This behavior can be investigated with good accuracy using finite element modeling. Although finite element models are able to incorporate frictional behavior of SGs, the absence of reliable values of coefficient of friction make these simulations unreliable. The aim of this paper is to demonstrate a method for determining the coefficients of friction of a self-expanding endovascular stent-graft. The methodology is demonstrated by considering three commercially available self-expanding SGs, labeled as A, B, and C. The SGs were compressed, expanded, and pulled out of polymeric cylinders of varying diameters and the pullout force was recorded in each case. The SG geometries were recreated using computer-aided design modeling and the entire experiment was simulated in ABAQUS 6.8/STANDARD. An optimization procedure was carried out for each SG oversize configuration to determine the COF that generated a frictional force corresponding to that measured in the experiment. The experimental pullout force and analytically determined COF for SGs A, B, and C were in the range of 6-9 N, 3-12 N, and 3-9 N and 0.08-0.16, 0.22-0.46, and 0.012-0.018, respectively. The computational model predicted COFs in the range of 0.00025-0.0055, 0.025-0.07, and 0.00025-0.006 for SGs A, B, and C, respectively. Our results suggest that for SGs A and B, which are exoskeleton based devices, the pullout forces increase upto a particular oversize beyond which they plateau, while pullout forces showed a continuous increase with oversize for SG C, which is an endoskeleton based device. The COF decreased with oversizing for both types of SGs. The proposed methodology will be useful for determining the COF between self-expanding stent-grafts from pullout tests on human arterial tissue.

Original languageEnglish (US)
Article number121007
JournalJournal of Biomechanical Engineering
Volume132
Issue number12
DOIs
StatePublished - Nov 8 2010

Fingerprint

Stents
Friction
Grafts
Transplants
Computer-Aided Design
Abdominal Aortic Aneurysm
ABAQUS
Aneurysm

Keywords

  • Coefficient of friction
  • Contact pressure
  • Endovascular repair
  • Finite element analysis
  • Self-expanding stent-grafts

ASJC Scopus subject areas

  • Biomedical Engineering
  • Physiology (medical)

Cite this

Determination of coefficient of friction for self-expanding stent-grafts. / Vad, Siddharth; Eskinazi, Amanda; Corbett, Timothy; McGloughlin, Tim; Vande Geest, Jonathan P.

In: Journal of Biomechanical Engineering, Vol. 132, No. 12, 121007, 08.11.2010.

Research output: Contribution to journalArticle

Vad, Siddharth ; Eskinazi, Amanda ; Corbett, Timothy ; McGloughlin, Tim ; Vande Geest, Jonathan P. / Determination of coefficient of friction for self-expanding stent-grafts. In: Journal of Biomechanical Engineering. 2010 ; Vol. 132, No. 12.
@article{7f8061d28f8140ce8ff2fc5b6752d09d,
title = "Determination of coefficient of friction for self-expanding stent-grafts",
abstract = "Migration of stent-grafts (SGs) after endovascular aneurysm repair of abdominal aortic aneurysms is a serious complication that may require secondary intervention. Experimental, analytical, and computational studies have been carried out in the past to understand the factors responsible for migration. In an experimental setting, it can be very challenging to correctly capture and understand the interaction between a SG and an artery. Quantities such as coefficient of friction (COF) and contact pressures that characterize this interaction are difficult to measure using an experimental approach. This behavior can be investigated with good accuracy using finite element modeling. Although finite element models are able to incorporate frictional behavior of SGs, the absence of reliable values of coefficient of friction make these simulations unreliable. The aim of this paper is to demonstrate a method for determining the coefficients of friction of a self-expanding endovascular stent-graft. The methodology is demonstrated by considering three commercially available self-expanding SGs, labeled as A, B, and C. The SGs were compressed, expanded, and pulled out of polymeric cylinders of varying diameters and the pullout force was recorded in each case. The SG geometries were recreated using computer-aided design modeling and the entire experiment was simulated in ABAQUS 6.8/STANDARD. An optimization procedure was carried out for each SG oversize configuration to determine the COF that generated a frictional force corresponding to that measured in the experiment. The experimental pullout force and analytically determined COF for SGs A, B, and C were in the range of 6-9 N, 3-12 N, and 3-9 N and 0.08-0.16, 0.22-0.46, and 0.012-0.018, respectively. The computational model predicted COFs in the range of 0.00025-0.0055, 0.025-0.07, and 0.00025-0.006 for SGs A, B, and C, respectively. Our results suggest that for SGs A and B, which are exoskeleton based devices, the pullout forces increase upto a particular oversize beyond which they plateau, while pullout forces showed a continuous increase with oversize for SG C, which is an endoskeleton based device. The COF decreased with oversizing for both types of SGs. The proposed methodology will be useful for determining the COF between self-expanding stent-grafts from pullout tests on human arterial tissue.",
keywords = "Coefficient of friction, Contact pressure, Endovascular repair, Finite element analysis, Self-expanding stent-grafts",
author = "Siddharth Vad and Amanda Eskinazi and Timothy Corbett and Tim McGloughlin and {Vande Geest}, {Jonathan P}",
year = "2010",
month = "11",
day = "8",
doi = "10.1115/1.4002798",
language = "English (US)",
volume = "132",
journal = "Journal of Biomechanical Engineering",
issn = "0148-0731",
publisher = "American Society of Mechanical Engineers(ASME)",
number = "12",

}

TY - JOUR

T1 - Determination of coefficient of friction for self-expanding stent-grafts

AU - Vad, Siddharth

AU - Eskinazi, Amanda

AU - Corbett, Timothy

AU - McGloughlin, Tim

AU - Vande Geest, Jonathan P

PY - 2010/11/8

Y1 - 2010/11/8

N2 - Migration of stent-grafts (SGs) after endovascular aneurysm repair of abdominal aortic aneurysms is a serious complication that may require secondary intervention. Experimental, analytical, and computational studies have been carried out in the past to understand the factors responsible for migration. In an experimental setting, it can be very challenging to correctly capture and understand the interaction between a SG and an artery. Quantities such as coefficient of friction (COF) and contact pressures that characterize this interaction are difficult to measure using an experimental approach. This behavior can be investigated with good accuracy using finite element modeling. Although finite element models are able to incorporate frictional behavior of SGs, the absence of reliable values of coefficient of friction make these simulations unreliable. The aim of this paper is to demonstrate a method for determining the coefficients of friction of a self-expanding endovascular stent-graft. The methodology is demonstrated by considering three commercially available self-expanding SGs, labeled as A, B, and C. The SGs were compressed, expanded, and pulled out of polymeric cylinders of varying diameters and the pullout force was recorded in each case. The SG geometries were recreated using computer-aided design modeling and the entire experiment was simulated in ABAQUS 6.8/STANDARD. An optimization procedure was carried out for each SG oversize configuration to determine the COF that generated a frictional force corresponding to that measured in the experiment. The experimental pullout force and analytically determined COF for SGs A, B, and C were in the range of 6-9 N, 3-12 N, and 3-9 N and 0.08-0.16, 0.22-0.46, and 0.012-0.018, respectively. The computational model predicted COFs in the range of 0.00025-0.0055, 0.025-0.07, and 0.00025-0.006 for SGs A, B, and C, respectively. Our results suggest that for SGs A and B, which are exoskeleton based devices, the pullout forces increase upto a particular oversize beyond which they plateau, while pullout forces showed a continuous increase with oversize for SG C, which is an endoskeleton based device. The COF decreased with oversizing for both types of SGs. The proposed methodology will be useful for determining the COF between self-expanding stent-grafts from pullout tests on human arterial tissue.

AB - Migration of stent-grafts (SGs) after endovascular aneurysm repair of abdominal aortic aneurysms is a serious complication that may require secondary intervention. Experimental, analytical, and computational studies have been carried out in the past to understand the factors responsible for migration. In an experimental setting, it can be very challenging to correctly capture and understand the interaction between a SG and an artery. Quantities such as coefficient of friction (COF) and contact pressures that characterize this interaction are difficult to measure using an experimental approach. This behavior can be investigated with good accuracy using finite element modeling. Although finite element models are able to incorporate frictional behavior of SGs, the absence of reliable values of coefficient of friction make these simulations unreliable. The aim of this paper is to demonstrate a method for determining the coefficients of friction of a self-expanding endovascular stent-graft. The methodology is demonstrated by considering three commercially available self-expanding SGs, labeled as A, B, and C. The SGs were compressed, expanded, and pulled out of polymeric cylinders of varying diameters and the pullout force was recorded in each case. The SG geometries were recreated using computer-aided design modeling and the entire experiment was simulated in ABAQUS 6.8/STANDARD. An optimization procedure was carried out for each SG oversize configuration to determine the COF that generated a frictional force corresponding to that measured in the experiment. The experimental pullout force and analytically determined COF for SGs A, B, and C were in the range of 6-9 N, 3-12 N, and 3-9 N and 0.08-0.16, 0.22-0.46, and 0.012-0.018, respectively. The computational model predicted COFs in the range of 0.00025-0.0055, 0.025-0.07, and 0.00025-0.006 for SGs A, B, and C, respectively. Our results suggest that for SGs A and B, which are exoskeleton based devices, the pullout forces increase upto a particular oversize beyond which they plateau, while pullout forces showed a continuous increase with oversize for SG C, which is an endoskeleton based device. The COF decreased with oversizing for both types of SGs. The proposed methodology will be useful for determining the COF between self-expanding stent-grafts from pullout tests on human arterial tissue.

KW - Coefficient of friction

KW - Contact pressure

KW - Endovascular repair

KW - Finite element analysis

KW - Self-expanding stent-grafts

UR - http://www.scopus.com/inward/record.url?scp=78049497349&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78049497349&partnerID=8YFLogxK

U2 - 10.1115/1.4002798

DO - 10.1115/1.4002798

M3 - Article

VL - 132

JO - Journal of Biomechanical Engineering

JF - Journal of Biomechanical Engineering

SN - 0148-0731

IS - 12

M1 - 121007

ER -