Advanced search
Add to list

Fluid-structure interaction of simplified Ross procedure as stepping stone to a fluid-solid-growth framework of arterial tissues

Author
Organization
Abstract
Introduction: We are developing a computational biomechanics fluid-structure-growth framework to better understand the mechano-biological interplay of arterial tissues in support of diagnosis, treatment and follow-up of patients with cardiovascular disorders. In the Ross procedure, a patient’s diseased aortic valve and root are replaced by a pulmonary autograft, but exposure to systemic conditions frequently leads to maladaptive growth and remodeling. Here, we report fluid-structure interaction simulations using data acquired in a sheep model of the simplified Ross procedure[1]. Methods: Phase contrast magnetic resonance imaging(PC-MRI) data were acquired one day after surgical replacement of a thoracic aortic segment by the pulmonary artery. A pre-stretched configuration at diastolic pressure of the sheep-specific geometry was obtained iteratively using the finite-element solver Abaqus (Dassault Systems, USA). A Gasser-Ogden-Holzapfel (GOH) model was used to describe the mechanical response of arterial tissue. We refer to [1] for more details. With this model as a starting point, an unstructured tetrahedral/prism mesh of the lumen was generated using ICEM( Ansys Inc, USA). A time-varying flat flow profile obtained from PC-MRI flow data taken was used as an inflow boundary condition. Downstream, a 3-element windkessel model was imposed whose parameters are tuned based on aortic pressure measurement during surgery (62/31mmHg). Fluent( Ansys Inc, USA) was used to solve the set of governing fluid equations with blood modeled as a Newtonian fluid and the assumption of laminar flow. Coupling of flow and structural solver was done using the in-house code CoCoNuT [2]. Three cardiac cycles were simulated with a time-step of 4.ms and the results from the last cycle were analyzed Results: Figure 1(b) shows an overall good correlation between volumetric flow rate obtained using FSI simulations and PC-MRI measurements at Plane-A. One day post-op, the yet to remodel pulmonary artery forms an aneurysm which exerts a windkessel-like function, with a diastolic-to-systolic volume change of 22.113% and dampening of velocity profiles from inlet to outlet (Figure 1(c)). Figure 1(d) shows displacement at the systolic configuration overlapped with diastolic configuration (grey) for reference. Discussion: These initial results are the stepping stone for fluid-structure-growth simulations for 180 days that incorporate wall shear stress as driver for remodeling. Validation will consist of comparing model predictions with experimental data, both in terms of final geometry as well as fractions of wall constituents. References: [1] Vastmans, J. et.al “Growth and remodeling in the pulmonary autograft: computational evaluation using kinematic growth models and constrained mixture theory”. Int J Numer Method Biomed Eng, doi: 10.1002/cnm.3545 (2021) [2] Degroote, J. et.al "Comparison of different quasi-Newton techniques for coupling of black box solvers", in ECCOMAS 2020, Proceedings, Paris, France, 2021

Citation

Please use this url to cite or link to this publication:

MLA
Balasubramanya, Amith, et al. “Fluid-Structure Interaction of Simplified Ross Procedure as Stepping Stone to a Fluid-Solid-Growth Framework of Arterial Tissues.” WCB 2022, 9th World Congress of Biomechanics, Abstracts, 2022.
APA
Balasubramanya, A., Vastmans, J., Maes, L., Peirlinck, M., Claus, P., Rega, F., … Segers, P. (2022). Fluid-structure interaction of simplified Ross procedure as stepping stone to a fluid-solid-growth framework of arterial tissues. WCB 2022, 9th World Congress of Biomechanics, Abstracts. Presented at the 9th World Congress of Biomechanics, Taipei, Taiwan.
Chicago author-date
Balasubramanya, Amith, Julie Vastmans, Lauranne Maes, Mathias Peirlinck, Piet Claus, Filip Rega, Joris Degroote, Nele Famaey, and Patrick Segers. 2022. “Fluid-Structure Interaction of Simplified Ross Procedure as Stepping Stone to a Fluid-Solid-Growth Framework of Arterial Tissues.” In WCB 2022, 9th World Congress of Biomechanics, Abstracts.
Chicago author-date (all authors)
Balasubramanya, Amith, Julie Vastmans, Lauranne Maes, Mathias Peirlinck, Piet Claus, Filip Rega, Joris Degroote, Nele Famaey, and Patrick Segers. 2022. “Fluid-Structure Interaction of Simplified Ross Procedure as Stepping Stone to a Fluid-Solid-Growth Framework of Arterial Tissues.” In WCB 2022, 9th World Congress of Biomechanics, Abstracts.
Vancouver
1.
Balasubramanya A, Vastmans J, Maes L, Peirlinck M, Claus P, Rega F, et al. Fluid-structure interaction of simplified Ross procedure as stepping stone to a fluid-solid-growth framework of arterial tissues. In: WCB 2022, 9th World Congress of Biomechanics, Abstracts. 2022.
IEEE
[1]
A. Balasubramanya et al., “Fluid-structure interaction of simplified Ross procedure as stepping stone to a fluid-solid-growth framework of arterial tissues,” in WCB 2022, 9th World Congress of Biomechanics, Abstracts, Taipei, Taiwan, 2022.
@inproceedings{8765205,
  abstract     = {{Introduction:
We are developing a computational biomechanics fluid-structure-growth framework to better understand the mechano-biological interplay of arterial tissues in support of diagnosis, treatment and follow-up of patients with cardiovascular disorders. In the Ross procedure, a patient’s diseased aortic valve and root are replaced by a pulmonary autograft, but exposure to systemic conditions frequently leads to maladaptive growth and remodeling. Here, we report fluid-structure interaction simulations using data acquired in a sheep model of the simplified Ross procedure[1].

Methods:
Phase contrast magnetic resonance imaging(PC-MRI) data were acquired one day after surgical replacement of a thoracic aortic segment by the pulmonary artery. A pre-stretched configuration at diastolic pressure of the sheep-specific geometry was obtained iteratively using the finite-element solver Abaqus (Dassault Systems, USA). A Gasser-Ogden-Holzapfel (GOH) model was used to describe the mechanical response of arterial tissue. We refer to [1] for more details. With this model as a starting point, an unstructured tetrahedral/prism mesh of the lumen was generated using ICEM( Ansys Inc, USA). A time-varying flat flow profile obtained from PC-MRI flow data taken was used as an inflow boundary condition. Downstream, a 3-element windkessel model was imposed whose parameters are tuned based on aortic pressure measurement during surgery (62/31mmHg). Fluent( Ansys Inc, USA) was used to solve the set of governing fluid equations with blood modeled as a Newtonian fluid and the assumption of laminar flow. Coupling of flow and structural solver was done using the in-house code CoCoNuT [2]. Three cardiac cycles were simulated with a time-step of 4.ms and the results from the last cycle were analyzed

Results:
Figure 1(b) shows an overall good correlation between volumetric flow rate obtained using FSI simulations and PC-MRI measurements at Plane-A. One day post-op, the yet to remodel pulmonary artery forms an aneurysm which exerts a windkessel-like function, with a diastolic-to-systolic volume change of 22.113% and dampening of velocity profiles from inlet to outlet (Figure 1(c)). Figure 1(d) shows displacement at the systolic configuration overlapped with diastolic configuration (grey) for reference.

Discussion:
These initial results are the stepping stone for fluid-structure-growth simulations for 180 days that incorporate wall shear stress as driver for remodeling. Validation will consist of comparing model predictions with experimental data, both in terms of final geometry as well as fractions of wall constituents.



References:

[1]  Vastmans, J. et.al “Growth and remodeling in the pulmonary autograft: computational evaluation using kinematic growth models and constrained mixture theory”. Int J Numer Method Biomed Eng, doi: 10.1002/cnm.3545 (2021)

[2] Degroote, J. et.al "Comparison of different quasi-Newton techniques for coupling of black box solvers", in ECCOMAS 2020, Proceedings, Paris, France, 2021}},
  author       = {{Balasubramanya, Amith and Vastmans, Julie and Maes, Lauranne and Peirlinck, Mathias and Claus, Piet and Rega, Filip and Degroote, Joris and Famaey, Nele and Segers, Patrick}},
  booktitle    = {{WCB 2022, 9th World Congress of Biomechanics, Abstracts}},
  language     = {{eng}},
  location     = {{Taipei, Taiwan}},
  title        = {{Fluid-structure interaction of simplified Ross procedure as stepping stone to a fluid-solid-growth framework of arterial tissues}},
  url          = {{https://www.wcb2022.com/}},
  year         = {{2022}},
}