Quantify patientspecific coronary material proper

Authors: Xiaoya Guo Jian Zhu Akiko Maehara David Monoly Habib Samady Liang Wang Kristen L Billiar Jie Zheng Chun Yang Gary S Mintz Don P Giddens Dalin Tang

Publish Date: 2016/08/25

Volume: 16, Issue: 1, Pages: 333-344

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Abstract

Computational models have been used to calculate plaque stress and strain for plaque progression and rupture investigations An intravascular ultrasound IVUSbased modeling approach is proposed to quantify in vivo vessel material properties for more accurate stress/strain calculations In vivo Cine IVUS and VHIVUS coronary plaque data were acquired from one patient with informed consent obtained Cine IVUS data and 3D thinslice models with axial stretch were used to determine patientspecific 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 10 11 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 7276 8137 10184 kPa and 00668 01046 and 01489 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 overestimations 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

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