title: Quantify patient-specific coronary material property and its impact on stress/strain calculations using in vivo IVUS data and 3D FSI models: a pilot study.
abstract: Computational models have been used to calculate plaque stress and strain for plaque progression and rupture investigations. An intravascular ultrasound (IVUS)-based modeling approach is proposed to quantify in vivo vessel material properties for more accurate stress/strain calculations. In vivo Cine IVUS and VH-IVUS coronary plaque data were acquired from one patient with informed consent obtained. Cine IVUS data and 3D thin-slice models with axial stretch were used to determine patient-specific vessel material properties. Twenty full 3D fluid-structure interaction models with ex vivo and in vivo material properties and various axial and circumferential shrink combinations were constructed to investigate the material stiffness impact on stress/strain calculations. The approximate circumferential Young's modulus over stretch ratio interval [1.0, 1.1] for an ex vivo human plaque sample and two slices (S6 and S18) from our IVUS data were 1631, 641, and 346 kPa, respectively. Average lumen stress/strain values from models using ex vivo, S6 and S18 materials with 5 % axial shrink and proper circumferential shrink were 72.76, 81.37, 101.84 kPa and 0.0668, 0.1046, and 0.1489, respectively. The average cap strain values from S18 material models were 150-180 % higher than those from the ex vivo material models. The corresponding percentages for the average cap stress values were 50-75 %. Dropping axial and circumferential shrink consideration led to stress and strain over-estimations. In vivo vessel material properties may be considerably softer than those from ex vivo data. Material stiffness variations may cause 50-75 % stress and 150-180 % strain variations.
authors: Department of Mathematics, Southeast University, Nanjing, 210096, China.
authors: Xiaoya
authors: X
authors: Guo
authors: Department of Cardiology, Zhongda Hospital, Southeast University, Nanjing, 210009, China.
authors: Jian
authors: J
authors: Zhu
authors: The Cardiovascular Research Foundation, Columbia University, New York, NY, 10022, USA.
authors: Akiko
authors: A
authors: Maehara
authors: Department of Medicine, Emory University School of Medicine, Atlanta, GA, 30307, USA.
authors: David
authors: D
authors: Monoly
authors: Department of Medicine, Emory University School of Medicine, Atlanta, GA, 30307, USA.
authors: Habib
authors: H
authors: Samady
authors: Mathematical Sciences Department, Worcester Polytechnic Institute, Worcester, MA, 01609, USA.
authors: Liang
authors: L
authors: Wang
authors: Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, 01609, USA.
authors: Kristen L
authors: KL
authors: Billiar
authors: Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO, 63110, USA.
authors: Jie
authors: J
authors: Zheng
authors: Network Technology Research Institute, China United Network Communications Co., Ltd., Beijing, China.
authors: Chun
authors: C
authors: Yang
authors: The Cardiovascular Research Foundation, Columbia University, New York, NY, 10022, USA.
authors: Gary S
authors: GS
authors: Mintz
authors: Department of Medicine, Emory University School of Medicine, Atlanta, GA, 30307, USA.|The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors: Don P
authors: DP
authors: Giddens
authors: Department of Mathematics, Southeast University, Nanjing, 210096, China. dtang@wpi.edu.|Mathematical Sciences Department, Worcester Polytechnic Institute, Worcester, MA, 01609, USA. dtang@wpi.edu.
authors: Dalin
authors: D
authors: Tang
mesh_terms: D055119:Elastic Modulus; D006801:Humans; D008954:Models, Biological; D010865:Pilot Projects; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography
keywords: Artery material properties; FSI; IVUS; Patient-specific model; Vulnerable plaque