1
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Berggren CC, Jiang D, Jack Wang YF, Bergquist JA, Rupp LC, Liu Z, MacLeod RS, Narayan A, Timmins LH. Influence of material parameter variability on the predicted coronary artery biomechanical environment via uncertainty quantification. Biomech Model Mechanobiol 2024; 23:927-940. [PMID: 38361087 PMCID: PMC11102342 DOI: 10.1007/s10237-023-01814-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 12/30/2023] [Indexed: 02/17/2024]
Abstract
Central to the clinical adoption of patient-specific modeling strategies is demonstrating that simulation results are reliable and safe. Indeed, simulation frameworks must be robust to uncertainty in model input(s), and levels of confidence should accompany results. In this study, we applied a coupled uncertainty quantification-finite element (FE) framework to understand the impact of uncertainty in vascular material properties on variability in predicted stresses. Univariate probability distributions were fit to material parameters derived from layer-specific mechanical behavior testing of human coronary tissue. Parameters were assumed to be probabilistically independent, allowing for efficient parameter ensemble sampling. In an idealized coronary artery geometry, a forward FE model for each parameter ensemble was created to predict tissue stresses under physiologic loading. An emulator was constructed within the UncertainSCI software using polynomial chaos techniques, and statistics and sensitivities were directly computed. Results demonstrated that material parameter uncertainty propagates to variability in predicted stresses across the vessel wall, with the largest dispersions in stress within the adventitial layer. Variability in stress was most sensitive to uncertainties in the anisotropic component of the strain energy function. Moreover, unary and binary interactions within the adventitial layer were the main contributors to stress variance, and the leading factor in stress variability was uncertainty in the stress-like material parameter that describes the contribution of the embedded fibers to the overall artery stiffness. Results from a patient-specific coronary model confirmed many of these findings. Collectively, these data highlight the impact of material property variation on uncertainty in predicted artery stresses and present a pipeline to explore and characterize forward model uncertainty in computational biomechanics.
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Affiliation(s)
- Caleb C Berggren
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - David Jiang
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Y F Jack Wang
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Jake A Bergquist
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Lindsay C Rupp
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Zexin Liu
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
| | - Rob S MacLeod
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Akil Narayan
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
| | - Lucas H Timmins
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA.
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA.
- School of Engineering Medicine, Texas A&M University, 1020 Holcombe Blvd., Houston, TX, USA.
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA.
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2
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Balasubramanya A, Maes L, Rega F, Mazzi V, Morbiducci U, Famaey N, Degroote J, Segers P. Hemodynamics and wall shear metrics in a pulmonary autograft: Comparing a fluid-structure interaction and computational fluid dynamics approach. Comput Biol Med 2024; 176:108604. [PMID: 38761502 DOI: 10.1016/j.compbiomed.2024.108604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 05/02/2024] [Accepted: 05/11/2024] [Indexed: 05/20/2024]
Abstract
OBJECTIVE In young patients, aortic valve disease is often treated by placement of a pulmonary autograft (PA) which adapts to its new environment through growth and remodeling. To better understand the hemodynamic forces acting on the highly distensible PA in the acute phase after surgery, we developed a fluid-structure interaction (FSI) framework and comprehensively compared hemodynamics and wall shear-stress (WSS) metrics with a computational fluid dynamic (CFD) simulation. METHODS The FSI framework couples a prestressed non-linear hyperelastic arterial tissue model with a fluid model using the in-house coupling code CoCoNuT. Geometry, material parameters and boundary conditions are based on in-vivo measurements. Hemodynamics, time-averaged WSS (TAWSS), oscillatory shear index (OSI) and topological shear variation index (TSVI) are evaluated qualitatively and quantitatively for 3 different sheeps. RESULTS Despite systolic-to-diastolic volumetric changes of the PA in the order of 20 %, the point-by-point correlation of TAWSS and OSI obtained through CFD and FSI remains high (r > 0.9, p < 0.01) for TAWSS and (r > 0.8, p < 0.01) for OSI). Instantaneous WSS divergence patterns qualitatively preserve similarities, but large deformations of the PA leads to a decrease of the correlation between FSI and CFD resolved TSVI (r < 0.7, p < 0.01). Moderate co-localization between FSI and CFD is observed for low thresholds of TAWSS and high thresholds of OSI and TSVI. CONCLUSION FSI might be warranted if we were to use the TSVI as a mechano-biological driver for growth and remodeling of PA due to varying intra-vascular flow structures and near wall hemodynamics because of the large expansion of the PA.
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Affiliation(s)
| | - Lauranne Maes
- Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Filip Rega
- Cardiac Surgery, Department of Cardiovascular Sciences, KU Leuven, Belgium
| | - Valentina Mazzi
- PolitoBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Umberto Morbiducci
- PolitoBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Nele Famaey
- Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Joris Degroote
- Department of Electromechanical Systems and Metal Engineering, Ghent University, Ghent, Belgium
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3
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Zuo D, Zhu M, Chen D, Xue Q. A computationally efficient gradient-enhanced healing model for soft biological tissues. Biomech Model Mechanobiol 2024:10.1007/s10237-024-01851-5. [PMID: 38733532 DOI: 10.1007/s10237-024-01851-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/17/2024] [Indexed: 05/13/2024]
Abstract
Soft biological tissues, such as arterial tissue, have the ability to grow and remodel in response to damage. Computational method plays a critical role in understanding the underlying mechanisms of tissue damage and healing. However, the existing healing model often requires huge computation time and it is inconvenient to implement finite element simulation. In this paper, we propose a computationally efficient gradient-enhanced healing model that combines the advantages of the gradient-enhanced damage model, the homeostatic-driven turnover remodeling model, and the damage-induced growth model. In the proposed model, the evolution of healing-related parameters can be solved explicitly. Additionally, an adaptive time increment method is used to further reduce computation time. The proposed model can be easily implemented in Abaqus, requiring only a user subroutine UMAT. The effectiveness of proposed model is verified through a semi-analytical example, and the influence of the variables in the proposed model is investigated using uniaxial tension and open-hole plate tests. Finally, the long-term development of aneurysms is simulated to demonstrate the potential applications of the proposed model in real biomechanical problems.
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Affiliation(s)
- Di Zuo
- Department of Engineering Mechanics, Dalian Jiaotong University, Dalian, 116028, People's Republic of China.
| | - Mingji Zhu
- Department of Engineering Mechanics, Dalian Jiaotong University, Dalian, 116028, People's Republic of China
| | - Daye Chen
- Department of Engineering Mechanics, Dalian Jiaotong University, Dalian, 116028, People's Republic of China
| | - Qiwen Xue
- Department of Engineering Mechanics, Dalian Jiaotong University, Dalian, 116028, People's Republic of China
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4
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Shim YD, Chen MC, Ha S, Chang HJ, Baek S, Lee EH. Multi-scaled temporal modeling of cardiovascular disease progression: An illustration of proximal arteries in pulmonary hypertension. J Biomech 2024; 168:112059. [PMID: 38631187 PMCID: PMC11096051 DOI: 10.1016/j.jbiomech.2024.112059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 03/16/2024] [Accepted: 03/21/2024] [Indexed: 04/19/2024]
Abstract
The progression of cardiovascular disease is intricately influenced by a complex interplay between physiological pathways, biochemical processes, and physical mechanisms. This study aimed to develop an in-silico physics-based approach to comprehensively model the multifaceted vascular pathophysiological adaptations. This approach focused on capturing the progression of proximal pulmonary arterial hypertension, which is significantly associated with the irreversible degradation of arterial walls and compensatory stress-induced growth and remodeling. This study incorporated critical characteristics related to the distinct time scales for the deformation, thus reflecting the impact of mean pressure on artery growth and tissue damage. The in-silico simulation of the progression of pulmonary hypertension was realized based on computational code combined with the finite element method (FEM) for the simulation of disease progression. The parametric studies further explored the consequences of these irreversible processes. This computational modeling approach may advance our understanding of pulmonary hypertension and its progression.
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Affiliation(s)
- Young-Dae Shim
- Department of Smart Fabrication Technology, Sungkyunkwan University, Suwon-si, Gyeonggi-do 16419, Republic of Korea.
| | - Mei-Cen Chen
- Department of Smart Fabrication Technology, Sungkyunkwan University, Suwon-si, Gyeonggi-do 16419, Republic of Korea.
| | - Seongmin Ha
- Biomedical Engineering, Yonsei University College of Medicine 250, Seoul, Republic of Korea.
| | - Hyuk-Jae Chang
- Division of Cardiology, Yonsei University College of Medicine 250, Seoul, Republic of Korea.
| | - Seungik Baek
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI 48824, United States.
| | - Eun-Ho Lee
- Department of Smart Fabrication Technology, Sungkyunkwan University, Suwon-si, Gyeonggi-do 16419, Republic of Korea; School of Mechanical Engineering, Sungkyunkwan University, Suwon-si, Gyeonggi-do 16419, Republic of Korea; Department of Intelligent Robotics, Sungkyunkwan University, Suwon-si, Gyeonggi-do 16419, Republic of Korea.
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5
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Estrada AC, Irons L, Tellides G, Humphrey JD. Multiscale computational model of aortic remodeling following postnatal disruption of TGFβ signaling. J Biomech 2024; 169:112152. [PMID: 38763809 PMCID: PMC11141772 DOI: 10.1016/j.jbiomech.2024.112152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/20/2024] [Accepted: 05/14/2024] [Indexed: 05/21/2024]
Abstract
The healthy adult aorta is a remarkably resilient structure, able to resist relentless cardiac-induced and hemodynamic loads under normal conditions. Fundamental to such mechanical homeostasis is the mechano-sensitive cell signaling that controls gene products and thus the structural integrity of the wall. Mouse models have shown that smooth muscle cell-specific disruption of transforming growth factor-beta (TGFβ) signaling during postnatal development compromises this resiliency, rendering the aortic wall susceptible to aneurysm and dissection under normal mechanical loading. By contrast, disruption of such signaling in the adult aorta appears to introduce a vulnerability that remains hidden under normal loading, but manifests under increased loading as experienced during hypertension. We present a multiscale (transcript to tissue) computational model to examine possible reasons for compromised mechanical homeostasis in the adult aorta following reduced TGFβ signaling in smooth muscle cells.
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Affiliation(s)
- Ana C Estrada
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Linda Irons
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - George Tellides
- Department of Surgery, Cardiothoracic, Yale School of Medicine, New Haven, CT, USA; Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
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6
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Coccarelli A, Van Loon R, Chien A. A Computational Pipeline to Investigate Longitudinal Blood Flow Changes in the Circle of Willis of Patients with Stable and Growing Aneurysms. Ann Biomed Eng 2024:10.1007/s10439-024-03493-1. [PMID: 38616236 DOI: 10.1007/s10439-024-03493-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/10/2024] [Indexed: 04/16/2024]
Abstract
Changes in cerebral blood flow are often associated with the initiation and development of different life-threatening medical conditions including aneurysm rupture and ischemic stroke. Nevertheless, it is not fully clear how haemodynamic changes in time across the Circle of Willis (CoW) are related with intracranial aneurysm (IA) growth. In this work, we introduced a novel reduced-order modelling strategy for the systematic quantification of longitudinal blood flow changes across the whole CoW in patients with stable and unstable/growing aneurysm. Magnetic Resonance Angiography (MRA) images were converted into one-dimensional (1-D) vessel networks through a semi-automated procedure, with a level of geometric reconstruction accuracy controlled by user-dependent parameters. The proposed pipeline was used to systematically analyse longitudinal haemodynamic changes in seven different clinical cases. Our preliminary simulation results indicate that growing aneurysms are not necessarily associated with significant changes in mean flow over time. A concise sensitivity analysis also shed light on which modelling aspects need to be further characterized to have reliable patient-specific predictions. This study poses the basis for investigating how time-dependent changes in the vasculature affect the haemodynamics across the whole CoW in patients with stable and growing aneurysms.
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Affiliation(s)
- Alberto Coccarelli
- Zienkiewicz Institute for Modelling, Data and AI, Faculty of Science and Engineering, Swansea University, Swansea, UK.
- Department of Mechanical Engineering, Faculty of Science and Engineering, Swansea University, Swansea, UK.
| | - Raoul Van Loon
- Zienkiewicz Institute for Modelling, Data and AI, Faculty of Science and Engineering, Swansea University, Swansea, UK
- Biomedical Engineering Simulation and Testing Lab, Department of Biomedical Engineering, Faculty of Science and Engineering, Swansea University, Swansea, UK
| | - Aichi Chien
- Radiological Sciences, School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, USA
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7
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Mello DS, Gioppato S, Antoniassi DQ, Vieira DC, Matos PH, Fernandes SA, Coelho-Filho OR, Schreiber R, Okawa RT, Sposito AC, Matos-Souza JR, Nadruz W. Association between carotid wall layers and invasively measured central blood pressure. Vasc Med 2024:1358863X241238708. [PMID: 38557167 DOI: 10.1177/1358863x241238708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Affiliation(s)
- Daniel Ss Mello
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Silvio Gioppato
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Diego Q Antoniassi
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Demétrio Cs Vieira
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Pedro Ha Matos
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Silvério A Fernandes
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Otavio R Coelho-Filho
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Roberto Schreiber
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Rogério Tp Okawa
- Department of Medicine, State University of Maringá, Marinas, Paraná, Brazil
| | - Andrei C Sposito
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - José R Matos-Souza
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
| | - Wilson Nadruz
- Department of Internal Medicine, School of Medical Sciences, State University of Campinas, Campinas, São Paulo, Brazil
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8
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Rego BV, Murtada SI, Li G, Tellides G, Humphrey JD. Multiscale insights into postnatal aortic development. Biomech Model Mechanobiol 2024; 23:687-701. [PMID: 38151614 DOI: 10.1007/s10237-023-01800-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/27/2023] [Indexed: 12/29/2023]
Abstract
Despite its vital importance for establishing proper cardiovascular function, the process through which the vasculature develops and matures postnatally remains poorly understood. From a clinical perspective, an ability to mechanistically model the developmental time course in arteries and veins, as well as to predict how various pathologies and therapeutic interventions alter the affected vessels, promises to improve treatment strategies and long-term clinical outcomes, particularly in pediatric patients suffering from congenital heart defects. In the present study, we conducted a multiscale investigation into the postnatal development of the murine thoracic aorta, examining key allometric relations as well as relationships between in vivo mechanical stresses, collagen and elastin expression, and the gradual accumulation of load-bearing constituents within the aortic wall. Our findings suggest that the production of fibrillar collagens in the developing aorta associates strongly with the ratio of circumferential stresses between systole and diastole, hence emphasizing the importance of a pulsatile mechanobiological stimulus. Moreover, rates of collagen turnover and elastic fiber compaction can be inferred directly by synthesizing transcriptional data and quantitative histological measurements of evolving collagen and elastin content. Consistent with previous studies, we also observed that wall shear stresses acting on the aorta are similar at birth and in maturity, supporting the hypothesis that at least some stress targets are established early in development and maintained thereafter, thus providing a possible homeostatic basis to guide future experiments and inform future predictive modeling.
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Affiliation(s)
- Bruno V Rego
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
- Department of Biological & Agricultural Engineering, Louisiana State University, Baton Rouge, LA, USA
| | - Sae-Il Murtada
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Guangxin Li
- Department of Surgery, Yale School of Medicine, New Haven, CT, USA
| | - George Tellides
- Department of Surgery, Yale School of Medicine, New Haven, CT, USA
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
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9
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Brown AL, Sexton ZA, Hu Z, Yang W, Marsden AL. Computational approaches for mechanobiology in cardiovascular development and diseases. Curr Top Dev Biol 2024; 156:19-50. [PMID: 38556423 DOI: 10.1016/bs.ctdb.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
The cardiovascular development in vertebrates evolves in response to genetic and mechanical cues. The dynamic interplay among mechanics, cell biology, and anatomy continually shapes the hydraulic networks, characterized by complex, non-linear changes in anatomical structure and blood flow dynamics. To better understand this interplay, a diverse set of molecular and computational tools has been used to comprehensively study cardiovascular mechanobiology. With the continual advancement of computational capacity and numerical techniques, cardiovascular simulation is increasingly vital in both basic science research for understanding developmental mechanisms and disease etiologies, as well as in clinical studies aimed at enhancing treatment outcomes. This review provides an overview of computational cardiovascular modeling. Beginning with the fundamental concepts of computational cardiovascular modeling, it navigates through the applications of computational modeling in investigating mechanobiology during cardiac development. Second, the article illustrates the utility of computational hemodynamic modeling in the context of treatment planning for congenital heart diseases. It then delves into the predictive potential of computational models for elucidating tissue growth and remodeling processes. In closing, we outline prevailing challenges and future prospects, underscoring the transformative impact of computational cardiovascular modeling in reshaping cardiovascular science and clinical practice.
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Affiliation(s)
- Aaron L Brown
- Department of Mechanical Engineering, Stanford University, Stanford, CA, United States
| | - Zachary A Sexton
- Department of Bioengineering, Stanford University, Stanford, CA, United States
| | - Zinan Hu
- Department of Mechanical Engineering, Stanford University, Stanford, CA, United States
| | - Weiguang Yang
- Department of Pediatrics, Stanford University, Stanford, CA, United States
| | - Alison L Marsden
- Department of Bioengineering, Stanford University, Stanford, CA, United States; Department of Pediatrics, Stanford University, Stanford, CA, United States.
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10
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Berggren CC, Jiang D, Jack Wang Y, Bergquist JA, Rupp LC, Liu Z, MacLeod RS, Narayan A, Timmins LH. Influence of Material Parameter Variability on the Predicted Coronary Artery Biomechanical Environment via Uncertainty Quantification. ARXIV 2024:arXiv:2401.15047v1. [PMID: 38344225 PMCID: PMC10854278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Central to the clinical adoption of patient-specific modeling strategies is demonstrating that simulation results are reliable and safe. Indeed, simulation frameworks must be robust to uncertainty in model input(s), and levels of confidence should accompany results. In this study, we applied a coupled uncertainty quantification-finite element (FE) framework to understand the impact of uncertainty in vascular material properties on variability in predicted stresses. Univariate probability distributions were fit to material parameters derived from layer-specific mechanical behavior testing of human coronary tissue. Parameters were assumed to be probabilistically independent, allowing for efficient parameter ensemble sampling. In an idealized coronary artery geometry, a forward FE model for each parameter ensemble was created to predict tissue stresses under physiologic loading. An emulator was constructed within the UncertainSCI software using polynomial chaos techniques, and statistics and sensitivities were directly computed. Results demonstrated that material parameter uncertainty propagates to variability in predicted stresses across the vessel wall, with the largest dispersions in stress within the adventitial layer. Variability in stress was most sensitive to uncertainties in the anisotropic component of the strain energy function. Moreover, unary and binary interactions within the adventitial layer were the main contributors to stress variance, and the leading factor in stress variability was uncertainty in the stress-like material parameter that describes the contribution of the embedded fibers to the overall artery stiffness. Results from a patient-specific coronary model confirmed many of these findings. Collectively, these data highlight the impact of material property variation on uncertainty in predicted artery stresses and present a pipeline to explore and characterize forward model uncertainty in computational biomechanics.
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Affiliation(s)
- Caleb C. Berggren
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - David Jiang
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Y.F. Jack Wang
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
| | - Jake A. Bergquist
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Lindsay C. Rupp
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Zexin Liu
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
| | - Rob S. MacLeod
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Akil Narayan
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- Department of Mathematics, University of Utah, Salt Lake City, UT, USA
| | - Lucas H. Timmins
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, USA
- Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, USA
- School of Engineering Medicine, Texas A&M University, Houston, TX, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
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11
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Schwarz EL, Pfaller MR, Szafron JM, Latorre M, Lindsey SE, Breuer CK, Humphrey JD, Marsden AL. A Fluid-Solid-Growth Solver for Cardiovascular Modeling. COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2023; 417:116312. [PMID: 38044957 PMCID: PMC10691594 DOI: 10.1016/j.cma.2023.116312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
We implement full, three-dimensional constrained mixture theory for vascular growth and remodeling into a finite element fluid-structure interaction (FSI) solver. The resulting "fluid-solid-growth" (FSG) solver allows long term, patient-specific predictions of changing hemodynamics, vessel wall morphology, tissue composition, and material properties. This extension from short term (FSI) to long term (FSG) simulations increases clinical relevance by enabling mechanobioloigcally-dependent studies of disease progression in complex domains.
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Affiliation(s)
- Erica L Schwarz
- Department of Bioengineering, Stanford Univeristy, Stanford, CA 94306, USA
| | - Martin R Pfaller
- Department of Pediatrics - Cardiology, Stanford Univeristy, Stanford, CA 94306, USA
| | - Jason M Szafron
- Department of Pediatrics - Cardiology, Stanford Univeristy, Stanford, CA 94306, USA
| | - Marcos Latorre
- Center for Research and Innovation in Bioengineering, Universitat Politècnica de València, València 46022, Spain
| | - Stephanie E Lindsey
- Department of Pediatrics - Cardiology, Stanford Univeristy, Stanford, CA 94306, USA
| | - Christopher K Breuer
- Department of Surgery, Nationwide Children's Hospital, Columbus, OH 43210, USA
- Center for Regenerative Medicine, Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, OH 43215, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale Univeristy, New Haven, CT 06520, USA
| | - Alison L Marsden
- Department of Bioengineering, Stanford Univeristy, Stanford, CA 94306, USA
- Department of Pediatrics - Cardiology, Stanford Univeristy, Stanford, CA 94306, USA
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12
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Gebauer AM, Pfaller MR, Braeu FA, Cyron CJ, Wall WA. A homogenized constrained mixture model of cardiac growth and remodeling: analyzing mechanobiological stability and reversal. Biomech Model Mechanobiol 2023; 22:1983-2002. [PMID: 37482576 PMCID: PMC10613155 DOI: 10.1007/s10237-023-01747-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 07/06/2023] [Indexed: 07/25/2023]
Abstract
Cardiac growth and remodeling (G&R) patterns change ventricular size, shape, and function both globally and locally. Biomechanical, neurohormonal, and genetic stimuli drive these patterns through changes in myocyte dimension and fibrosis. We propose a novel microstructure-motivated model that predicts organ-scale G&R in the heart based on the homogenized constrained mixture theory. Previous models, based on the kinematic growth theory, reproduced consequences of G&R in bulk myocardial tissue by prescribing the direction and extent of growth but neglected underlying cellular mechanisms. In our model, the direction and extent of G&R emerge naturally from intra- and extracellular turnover processes in myocardial tissue constituents and their preferred homeostatic stretch state. We additionally propose a method to obtain a mechanobiologically equilibrated reference configuration. We test our model on an idealized 3D left ventricular geometry and demonstrate that our model aims to maintain tensional homeostasis in hypertension conditions. In a stability map, we identify regions of stable and unstable G&R from an identical parameter set with varying systolic pressures and growth factors. Furthermore, we show the extent of G&R reversal after returning the systolic pressure to baseline following stage 1 and 2 hypertension. A realistic model of organ-scale cardiac G&R has the potential to identify patients at risk of heart failure, enable personalized cardiac therapies, and facilitate the optimal design of medical devices.
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Affiliation(s)
- Amadeus M Gebauer
- Institute for Computational Mechanics, Technical University of Munich, 85748, Garching, Germany.
| | - Martin R Pfaller
- Pediatric Cardiology, Stanford Maternal & Child Health Research Institute, and Institute for Computational and Mathematical Engineering, Stanford University, Stanford, USA
| | - Fabian A Braeu
- Ophthalmic Engineering & Innovation Laboratory, Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christian J Cyron
- Institute of Continuum and Material Mechanics, Hamburg University of Technology, 21073, Hamburg, Germany
- Institute of Material Systems Modeling, Helmholtz-Zentrum Hereon, 21502, Geesthacht, Germany
| | - Wolfgang A Wall
- Institute for Computational Mechanics, Technical University of Munich, 85748, Garching, Germany
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13
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Hutcheson JD. From Flow to Pharmaceuticals: Single-Cell Mechanobiology and Drug Efficacy. Arterioscler Thromb Vasc Biol 2023; 43:2282-2284. [PMID: 37942613 DOI: 10.1161/atvbaha.123.320117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Affiliation(s)
- Joshua D Hutcheson
- Department of Biomedical Engineering and Biomolecular Sciences Institute, Florida International University, Miami
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14
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Szafron JM, Yang W, Feinstein JA, Rabinovitch M, Marsden AL. A computational growth and remodeling framework for adaptive and maladaptive pulmonary arterial hemodynamics. Biomech Model Mechanobiol 2023; 22:1935-1951. [PMID: 37658985 PMCID: PMC10929588 DOI: 10.1007/s10237-023-01744-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/05/2023] [Indexed: 09/05/2023]
Abstract
Hemodynamic loading is known to contribute to the development and progression of pulmonary arterial hypertension (PAH). This loading drives changes in mechanobiological stimuli that affect cellular phenotypes and lead to pulmonary vascular remodeling. Computational models have been used to simulate mechanobiological metrics of interest, such as wall shear stress, at single time points for PAH patients. However, there is a need for new approaches that simulate disease evolution to allow for prediction of long-term outcomes. In this work, we develop a framework that models the pulmonary arterial tree through adaptive and maladaptive responses to mechanical and biological perturbations. We coupled a constrained mixture theory-based growth and remodeling framework for the vessel wall with a morphometric tree representation of the pulmonary arterial vasculature. We show that non-uniform mechanical behavior is important to establish the homeostatic state of the pulmonary arterial tree, and that hemodynamic feedback is essential for simulating disease time courses. We also employed a series of maladaptive constitutive models, such as smooth muscle hyperproliferation and stiffening, to identify critical contributors to development of PAH phenotypes. Together, these simulations demonstrate an important step toward predicting changes in metrics of clinical interest for PAH patients and simulating potential treatment approaches.
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Affiliation(s)
- Jason M Szafron
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
- Cardiovascular Institute, Stanford University, Palo Alto, CA, 94305, USA
| | - Weiguang Yang
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
| | - Jeffrey A Feinstein
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
- Cardiovascular Institute, Stanford University, Palo Alto, CA, 94305, USA
| | - Marlene Rabinovitch
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
- Cardiovascular Institute, Stanford University, Palo Alto, CA, 94305, USA
| | - Alison L Marsden
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA.
- Cardiovascular Institute, Stanford University, Palo Alto, CA, 94305, USA.
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15
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Tilahun HG, Mullagura HN, Humphrey JD, Baek S. A biochemomechanical model of collagen turnover in arterial adaptations to hemodynamic loading. Biomech Model Mechanobiol 2023; 22:2063-2082. [PMID: 37505299 DOI: 10.1007/s10237-023-01750-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 07/06/2023] [Indexed: 07/29/2023]
Abstract
The production, removal, and remodeling of fibrillar collagen is fundamental to mechanical homeostasis in arteries, including dynamic morphological and microstructural changes that occur in response to sustained changes in blood flow and pressure under physiological conditions. These dynamic processes involve complex, coupled biological, chemical, and mechanical mechanisms that are not completely understood. Nevertheless, recent simulations using constrained mixture models with phenomenologically motivated constitutive relations have proven able to predict salient features of the progression of certain vascular adaptations as well as disease processes. Collagen turnover is modeled, in part, via stress-dependent changes in collagen half-life, typically within the range of 10-70 days. By contrast, in this work we introduce a biochemomechanical approach to model the cellular synthesis of procollagen as well as its transition from an intermediate state of assembled microfibrils to mature cross-linked fibers, with mechano-regulated removal. The resulting model can simulate temporal changes in geometry, composition, and stress during early vascular adaptation (weeks to months) for modest changes in blood flow or pressure. It is shown that these simulations capture salient features from data presented in the literature from different animal models.
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Affiliation(s)
- Hailu G Tilahun
- Department of Mechanical Engineering, Michigan State University, 3259 Engineering Building, East Lansing, MI, 48824, USA
| | - Haritha N Mullagura
- Department of Mechanical Engineering, Michigan State University, 3259 Engineering Building, East Lansing, MI, 48824, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, 06520, USA
| | - Seungik Baek
- Department of Mechanical Engineering, Michigan State University, 3259 Engineering Building, East Lansing, MI, 48824, USA.
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16
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van Asten JGM, Latorre M, Karakaya C, Baaijens FPT, Sahlgren CM, Ristori T, Humphrey JD, Loerakker S. A multiscale computational model of arterial growth and remodeling including Notch signaling. Biomech Model Mechanobiol 2023; 22:1569-1588. [PMID: 37024602 PMCID: PMC10511605 DOI: 10.1007/s10237-023-01697-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 01/31/2023] [Indexed: 04/08/2023]
Abstract
Blood vessels grow and remodel in response to mechanical stimuli. Many computational models capture this process phenomenologically, by assuming stress homeostasis, but this approach cannot unravel the underlying cellular mechanisms. Mechano-sensitive Notch signaling is well-known to be key in vascular development and homeostasis. Here, we present a multiscale framework coupling a constrained mixture model, capturing the mechanics and turnover of arterial constituents, to a cell-cell signaling model, describing Notch signaling dynamics among vascular smooth muscle cells (SMCs) as influenced by mechanical stimuli. Tissue turnover was regulated by both Notch activity, informed by in vitro data, and a phenomenological contribution, accounting for mechanisms other than Notch. This novel framework predicted changes in wall thickness and arterial composition in response to hypertension similar to previous in vivo data. The simulations suggested that Notch contributes to arterial growth in hypertension mainly by promoting SMC proliferation, while other mechanisms are needed to fully capture remodeling. The results also indicated that interventions to Notch, such as external Jagged ligands, can alter both the geometry and composition of hypertensive vessels, especially in the short term. Overall, our model enables a deeper analysis of the role of Notch and Notch interventions in arterial growth and remodeling and could be adopted to investigate therapeutic strategies and optimize vascular regeneration protocols.
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Affiliation(s)
- Jordy G M van Asten
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Marcos Latorre
- Center for Research and Innovation in Bioengineering, Universitat Politècnica de València, València, Spain
| | - Cansu Karakaya
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Frank P T Baaijens
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Cecilia M Sahlgren
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
- Faculty of Science and Engineering, Biosciences, Åbo Akademi, Turku, Finland
| | - Tommaso Ristori
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Sandra Loerakker
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands.
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17
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Murtada SI, Latorre M, Humphrey JD. Remodeling of the uterine artery during and early after pregnancy in the mouse. Biomech Model Mechanobiol 2023; 22:1531-1540. [PMID: 36550244 DOI: 10.1007/s10237-022-01674-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022]
Abstract
Pregnancy associates with dramatic changes in maternal cardiovascular physiology that ensure that the utero-placental circulation can support the developing fetus. Particularly striking is the marked flow-induced remodeling of uterine arteries during pregnancy and their recovery following birth. Whereas details are available in the literature on alterations in hemodynamics within and changes in the dimensions of uterine arteries during and following pregnancy in mice, we report here the first biaxial biomechanical phenotyping of these arteries during this dynamic period of growth and remodeling (G&R). To gain additional insight into the measured G&R, we also use a computational constrained mixture model to describe and predict findings, including simulations related to complications that may arise during pregnancy. It is found that dramatic pregnancy-induced remodeling of the uterine artery is largely, but not completely, reversed in the postpartum period, which appears to be driven by increases in collagen turnover among other intramural changes. By contrast, data on the remodeling of the ascending aorta, an elastic artery, reveal modest changes that are fully recovered postpartum. There is strong motivation to continue biomechanical studies on this critical aspect of women's health, which has heretofore not received appropriate consideration from the biomechanics community.
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Affiliation(s)
- Sae-Il Murtada
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Marcos Latorre
- Center for Research and Innovation in Bioengineering, Universitat Politècnica de València, Valencia, Spain
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
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18
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Guan D, Zhuan X, Luo X, Gao H. An updated Lagrangian constrained mixture model of pathological cardiac growth and remodelling. Acta Biomater 2023; 166:375-399. [PMID: 37201740 DOI: 10.1016/j.actbio.2023.05.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 05/03/2023] [Accepted: 05/10/2023] [Indexed: 05/20/2023]
Abstract
Progressive left ventricular (LV) growth and remodelling (G&R) is often induced by volume and pressure overload, characterized by structural and functional adaptation through myocyte hypertrophy and extracellular matrix remodelling, which are dynamically regulated by biomechanical factors, inflammation, neurohormonal pathways, etc. When prolonged, it can eventually lead to irreversible heart failure. In this study, we have developed a new framework for modelling pathological cardiac G&R based on constrained mixture theory using an updated reference configuration, which is triggered by altered biomechanical factors to restore biomechanical homeostasis. Eccentric and concentric growth, and their combination have been explored in a patient-specific human LV model under volume and pressure overload. Eccentric growth is triggered by overstretching of myofibres due to volume overload, i.e. mitral regurgitation, whilst concentric growth is driven by excessive contractile stress due to pressure overload, i.e. aortic stenosis. Different biological constituent's adaptations under pathological conditions are integrated together, which are the ground matrix, myofibres and collagen network. We have shown that this constrained mixture-motivated G&R model can capture different phenotypes of maladaptive LV G&R, such as chamber dilation and wall thinning under volume overload, wall thickening under pressure overload, and more complex patterns under both pressure and volume overload. We have further demonstrated how collagen G&R would affect LV structural and functional adaption by providing mechanistic insight on anti-fibrotic interventions. This updated Lagrangian constrained mixture based myocardial G&R model has the potential to understand the turnover processes of myocytes and collagen due to altered local mechanical stimuli in heart diseases, and in providing mechanistic links between biomechanical factors and biological adaption at both the organ and cellular levels. Once calibrated with patient data, it can be used for assessing heart failure risk and designing optimal treatment therapies. STATEMENT OF SIGNIFICANCE: Computational modelling of cardiac G&R has shown high promise to provide insight into heart disease management when mechanistic understandings are quantified between biomechanical factors and underlying cellular adaptation processes. The kinematic growth theory has been dominantly used to phenomenologically describe the biological G&R process but neglecting underlying cellular mechanisms. We have developed a constrained mixture based G&R model with updated reference by taking into account different mechanobiological processes in the ground matrix, myocytes and collagen fibres. This G&R model can serve as a basis for developing more advanced myocardial G&R models further informed by patient data to assess heart failure risk, predict disease progression, select the optimal treatment by hypothesis testing, and eventually towards a truly precision cardiology using in-silico models.
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Affiliation(s)
- Debao Guan
- School of Mathematics and Statistics, University of Glasgow, Glasgow G12 8QQ, UK
| | - Xin Zhuan
- School of Mathematics and Statistics, University of Glasgow, Glasgow G12 8QQ, UK
| | - Xiaoyu Luo
- School of Mathematics and Statistics, University of Glasgow, Glasgow G12 8QQ, UK
| | - Hao Gao
- School of Mathematics and Statistics, University of Glasgow, Glasgow G12 8QQ, UK.
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19
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Irons L, Cavinato C, Humphrey JD. Persistent non-homeostatic remodeling of aortic collagen following a brief episode of hypertension: A computational study. J Mech Behav Biomed Mater 2023; 144:105966. [PMID: 37327590 PMCID: PMC10353492 DOI: 10.1016/j.jmbbm.2023.105966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/23/2023] [Accepted: 06/06/2023] [Indexed: 06/18/2023]
Abstract
The healthy adult aorta exhibits a remarkable homeostatic ability to respond to sustained changes in hemodynamic loads under many circumstances, but this mechanical homeostasis can be compromised or lost in natural aging and diverse pathological processes. Herein, we investigate persistent non-homeostatic changes in the composition and mechanical properties of the thoracic aorta in adult wild-type mice following 14 days of angiotensin II-induced hypertension. We employ a multiscale computational model of arterial growth and remodeling driven by mechanosensitive and angiotensin II-related cell signaling pathways. We find that experimentally observed findings can only be recapitulated computationally if the collagen deposited during the transient period of hypertension has altered properties (deposition stretch, fiber angle, crosslinking) compared with the collagen produced in the original homeostatic state. Some of these changes are predicted to persist for at least six months after blood pressure is restored to normal levels, consistent with the experimental findings.
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Affiliation(s)
- Linda Irons
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Cristina Cavinato
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
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20
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Maes L, Famaey N. How to implement constrained mixture growth and remodeling algorithms for soft biological tissues. J Mech Behav Biomed Mater 2023; 140:105733. [PMID: 36821910 DOI: 10.1016/j.jmbbm.2023.105733] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 01/31/2023] [Accepted: 02/13/2023] [Indexed: 02/22/2023]
Abstract
Biological soft tissues are constantly adapting to their mechanical environment and remodel to restore certain mechanobiological homeostatic conditions. These effects can be modeled using the constrained mixture theory, that assumes degradation of material over time and the gradual replacement of extant material by newly deposited material. While this theory presents an elegant way to grasp phenomena of growth and remodeling in soft biological tissues, implementation difficulties may arise. Therefore, we give a detailed overview of the mathematical description of the constrained mixture theory and its homogenized equivalent, and present practical suggestions to numerically implement the theories. These implementations are thoroughly tested with multiple example growth and remodeling models. Results show a good correspondence between both theories, with the homogenized theory favored in terms of time efficiency. Results of a step time convergence study show the importance of choosing a small enough time step, especially when using the classical theory.
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Affiliation(s)
- Lauranne Maes
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Celestijnenlaan 300 box 2419, 3001 Leuven, Belgium.
| | - Nele Famaey
- Biomechanics Section, Department of Mechanical Engineering, KU Leuven, Celestijnenlaan 300 box 2419, 3001 Leuven, Belgium.
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21
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Tilahun HG, Mullagura HN, Humphrey JD, Baek S. A Biochemomechanical Model of Collagen Turnover in Arterial Adaptations to Hemodynamic Loading. RESEARCH SQUARE 2023:rs.3.rs-2535591. [PMID: 36798195 PMCID: PMC9934758 DOI: 10.21203/rs.3.rs-2535591/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The production, removal, and remodeling of fibrillar collagen is fundamental to arterial homeostasis, including dynamic morphological and microstructural changes that occur in response to sustained changes in blood flow and pressure under physiological conditions. These dynamic processes involve complex, coupled biological, chemical, and mechanical mechanisms that are not completely understood. Nevertheless, recent simulations using constrained mixture models with phenomenologically motivated constitutive relations have demonstrated a capability to predict salient features of the progression of certain vascular adaptations and disease processes. Collagen turnover is modeled, in part, via stress-dependent changes in collagen half-life, typically taken within the range of 10â€"70 days. By contrast, in this work we introduce a biochemomechanical approach to model the cellular synthesis of procollagen as well as its transition from an intermediate state of assembled microfibrils to mature cross-linked fibers, with mechano-regulated removal. The resulting model can simulate temporal changes in geometry, composition, and stress during early vascular adaptation (weeks to months) for modest changes in blood flow or pressure. It is shown that these simulations capture salient features from data presented in the literature from different animal models.
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Affiliation(s)
- Hailu G. Tilahun
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA
| | - Haritha N. Mullagura
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA
| | - Jay D. Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Seungik Baek
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA
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22
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Loerakker S, Humphrey JD. Computer Model-Driven Design in Cardiovascular Regenerative Medicine. Ann Biomed Eng 2023; 51:45-57. [PMID: 35974236 PMCID: PMC9832109 DOI: 10.1007/s10439-022-03037-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/20/2022] [Indexed: 01/28/2023]
Abstract
Continuing advances in genomics, molecular and cellular mechanobiology and immunobiology, including transcriptomics and proteomics, and biomechanics increasingly reveal the complexity underlying native tissue and organ structure and function. Identifying methods to repair, regenerate, or replace vital tissues and organs remains one of the greatest challenges of modern biomedical engineering, one that deserves our very best effort. Notwithstanding the continuing need for improving standard methods of investigation, including cell, organoid, and tissue culture, biomaterials development and fabrication, animal models, and clinical research, it is increasingly evident that modern computational methods should play increasingly greater roles in advancing the basic science, bioengineering, and clinical application of regenerative medicine. This brief review focuses on the development and application of computational models of tissue and organ mechanobiology and mechanics for purposes of designing tissue engineered constructs and understanding their development in vitro and in situ. Although the basic approaches are general, for illustrative purposes we describe two recent examples from cardiovascular medicine-tissue engineered heart valves (TEHVs) and tissue engineered vascular grafts (TEVGs)-to highlight current methods of approach as well as continuing needs.
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Affiliation(s)
- Sandra Loerakker
- Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, Netherlands
| | - Jay D Humphrey
- Department of Biomedical Engineering and Vascular Biology & Therapeutics Program, Yale University and Yale School of Medicine, New Haven, CT, USA.
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23
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Irons L, Estrada AC, Humphrey JD. Intracellular signaling control of mechanical homeostasis in the aorta. Biomech Model Mechanobiol 2022; 21:1339-1355. [PMID: 35867282 PMCID: PMC10547132 DOI: 10.1007/s10237-022-01593-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 05/10/2022] [Indexed: 11/27/2022]
Abstract
Mature arteries exhibit a preferred biomechanical state in health evidenced by a narrow range of intramural and wall shear stresses. When stresses are perturbed by changes in blood pressure or flow, homeostatic mechanisms tend to restore target values via altered contractility and/or cell and matrix turnover. In contrast, vascular disease associates with compromised homeostasis, hence we must understand mechanisms underlying mechanical homeostasis and its robustness. Here, we use a multiscale computational model wherein mechanosensitive intracellular signaling pathways drive arterial growth and remodeling. First, we identify an ensemble of cell-level parameterizations where tissue-level responses are well-regulated and adaptive to hemodynamic perturbations. The responsible mechanism is persistent multiscale negative feedback whereby mechanosensitive signaling drives mass turnover until homeostatic target stresses are reached. This demonstrates how robustness emerges despite inevitable cell and individual heterogeneity. Second, we investigate tissue-level effects of signaling node knockdowns (ATIR, ROCK, TGF[Formula: see text]RII, PDGFR, ERK1/2) and find general agreement with experimental reports of fault tolerance. Robustness against structural changes manifests via low engagement of the node under baseline stresses or compensatory multiscale feedback via upregulation of additional pathways. Third, we show how knockdowns affect collagen and smooth muscle turnover at baseline and with perturbed stresses. In several cases, basal production is not remarkably affected, but sensitivities to stress deviations, which influence feedback strength, are reduced. Such reductions can impair adaptive responses, consistent with previously reported aortic vulnerability despite grossly normal appearances. Reduced stress sensitivities thus form a candidate mechanism for how robustness is lost, enabling transitions from health towards disease.
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Affiliation(s)
- Linda Irons
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Ana C Estrada
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA.
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24
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Cheng F, Watton PN, Pederzani G, Kurobe M, Takaoka EI, Chapple C, Birder L, Yoshimura N, Robertson AM. A constrained mixture-micturition-growth (CMMG) model of the urinary bladder: Application to partial bladder outlet obstruction (BOO). J Mech Behav Biomed Mater 2022; 134:105337. [PMID: 35863296 PMCID: PMC9835014 DOI: 10.1016/j.jmbbm.2022.105337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/13/2022] [Accepted: 06/24/2022] [Indexed: 01/14/2023]
Abstract
We present a constrained mixture-micturition-growth (CMMG) model for the bladder. It simulates bladder mechanics, voiding function (micturition) and tissue adaptations in response to altered biomechanical conditions. The CMMG model is calibrated with both in vivo and in vitro data from healthy male rat urinary bladders (cystometry, bioimaging of wall structure, mechanical testing) and applied to simulate the growth and remodeling (G&R) response to partial bladder outlet obstruction (BOO). The bladder wall is represented as a multi-layered, anisotropic, nonlinear constrained mixture. A short time scale micturition component of the CMMG model accounts for the active and passive mechanics of voiding. Over a second, longer time scale, G&R algorithms for the evolution of both cellular and extracellular constituents act to maintain/restore bladder (homeostatic) functionality. The CMMG model is applied to a spherical membrane model of the BOO bladder utilizing temporal data from an experimental male rodent model to parameterize and then verify the model. Consistent with the experimental studies of BOO, the model predicts: an initial loss of voiding capacity followed by hypertrophy of SMC to restore voiding function; bladder enlargement; collagen remodeling to maintain its role as a protective sheath; and increased voiding duration with lower average flow rate. This CMMG model enables a mechanistic approach for investigating the bladder's structure-function relationship and its adaption in pathological conditions. While the approach is illustrated with a conceptual spherical bladder model, it provides the basis for application of the CMMG model to anatomical geometries. Such a mechanistic approach has promise as an in silico tool for the rational development of new surgical and pharmacological treatments for bladder diseases such as BOO.
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Affiliation(s)
- Fangzhou Cheng
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States
| | - Paul N Watton
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States; Department of Computer Science & Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom.
| | - Giulia Pederzani
- Department of Computer Science & Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
| | - Masahiro Kurobe
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Ei-Ichiro Takaoka
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Chris Chapple
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
| | - Lori Birder
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom; Department of Medicine, University of Pittsburgh, United States
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Anne M Robertson
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States
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25
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Smith KA, Lin AH, Stevens AH, Yu SM, Weiss JA, Timmins LH. Collagen Molecular Damage is a Hallmark of Early Atherosclerosis Development. J Cardiovasc Transl Res 2022; 16:463-472. [PMID: 36097314 DOI: 10.1007/s12265-022-10316-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/30/2022] [Indexed: 10/14/2022]
Abstract
Remodeling of extracellular matrix proteins underlies the development of cardiovascular disease. Herein, we utilized a novel molecular probe, collagen hybridizing peptide (CHP), to target collagen molecular damage during atherogenesis. The thoracic aorta was dissected from ApoE-/- mice that had been on a high-fat diet for 0-18 weeks. Using an optimized protocol, tissues were stained with Cy3-CHP and digested to quantify CHP with a microplate assay. Results demonstrated collagen molecular damage, inferred from Cy3-CHP fluorescence, was a function of location and time on the high-fat diet. Tissue from the aortic arch showed a significant increase in collagen molecular damage after 18 weeks, while no change was observed in tissue from the descending aorta. No spatial differences in fluorescence were observed between the superior and inferior arch tissue. Our results provide insight into the early changes in collagen during atherogenesis and present a new opportunity in the subclinical diagnosis of atherosclerosis.
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Affiliation(s)
- Kelly A Smith
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA
| | - Allen H Lin
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA.,Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, 84112, USA
| | - Alexander H Stevens
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA
| | - S Michael Yu
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA.,Department of Molecular Pharmaceutics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Jeffrey A Weiss
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA.,Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, 84112, USA.,Department of Orthopaedics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Lucas H Timmins
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, 84112, USA. .,Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT, 84112, USA.
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26
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Han HC, Liu Q, Baek S. Numerical simulations of the nonsymmetric growth and remodeling of arteries under axial twisting. J Biomech 2022; 140:111165. [PMID: 35667148 PMCID: PMC10782577 DOI: 10.1016/j.jbiomech.2022.111165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 05/02/2022] [Accepted: 05/23/2022] [Indexed: 11/23/2022]
Abstract
Blood vessels are often subjected to axial twisting during body movement or surgery. Sustained twisting may lead to blood vessel growth and remodeling, however, it remains unclear how the extracellular matrix in the blood vessels remodel under sustained axial twisting. This study aimed to develop a computational model to simulate stress-induced growth and remodeling (G&R) of thin-walled blood vessels under axial twisting. Cylindrical vessels were subjected to a step increase in axial torque while the axial stretch and lumen pressure remained constant. The vessel walls were modeled based on the constrained mixture theory given as microstructure-based discrete fiber families with isotropic matrix structure models. Simulation results demonstrated that in response to a constant twist angle loading, arterial wall thickness, mass, and twisting torque gradually increase towards a new steady state. However, the stress and mass decrease in one diagonal fiber family while increasing in the other diagonal fiber family before reaching plateaus. A novel finding was that the two helical collagen fiber families showed different growth rates and patterns during remodeling, driven by the different fiber stresses generated by the twisting, and led to non-symmetric material properties. This study sheds new light on arterial wall remodeling under axial twisting.
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Affiliation(s)
- Hai-Chao Han
- Department of Mechanical Engineering, The University of Texas at San Antonio, TX 78249, United States.
| | - Qin Liu
- Department of Mechanical Engineering, The University of Texas at San Antonio, TX 78249, United States
| | - Seungik Baek
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI 48824, United States
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27
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Neelakantan S, Xin Y, Gaver DP, Cereda M, Rizi R, Smith BJ, Avazmohammadi R. Computational lung modelling in respiratory medicine. J R Soc Interface 2022; 19:20220062. [PMID: 35673857 PMCID: PMC9174712 DOI: 10.1098/rsif.2022.0062] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Computational modelling of the lungs is an active field of study that integrates computational advances with lung biophysics, biomechanics, physiology and medical imaging to promote individualized diagnosis, prognosis and therapy evaluation in lung diseases. The complex and hierarchical architecture of the lung offers a rich, but also challenging, research area demanding a cross-scale understanding of lung mechanics and advanced computational tools to effectively model lung biomechanics in both health and disease. Various approaches have been proposed to study different aspects of respiration, ranging from compartmental to discrete micromechanical and continuum representations of the lungs. This article reviews several developments in computational lung modelling and how they are integrated with preclinical and clinical data. We begin with a description of lung anatomy and how different tissue components across multiple length scales affect lung mechanics at the organ level. We then review common physiological and imaging data acquisition methods used to inform modelling efforts. Building on these reviews, we next present a selection of model-based paradigms that integrate data acquisitions with modelling to understand, simulate and predict lung dynamics in health and disease. Finally, we highlight possible future directions where computational modelling can improve our understanding of the structure–function relationship in the lung.
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Affiliation(s)
- Sunder Neelakantan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
| | - Yi Xin
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Donald P. Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
| | - Maurizio Cereda
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rahim Rizi
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Bradford J. Smith
- Department of Bioengineering, University of Colorado Denver
- Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatric Pulmonary and Sleep Medicine, School of Medicine, University of Colorado, Aurora, CO, USA
| | - Reza Avazmohammadi
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
- J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, USA
- Department of Cardiovascular Sciences, Houston Methodist Academic Institute, Houston, TX, USA
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28
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Bracamonte JH, Saunders SK, Wilson JS, Truong UT, Soares JS. Patient-Specific Inverse Modeling of In Vivo Cardiovascular Mechanics with Medical Image-Derived Kinematics as Input Data: Concepts, Methods, and Applications. APPLIED SCIENCES-BASEL 2022; 12:3954. [PMID: 36911244 PMCID: PMC10004130 DOI: 10.3390/app12083954] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Inverse modeling approaches in cardiovascular medicine are a collection of methodologies that can provide non-invasive patient-specific estimations of tissue properties, mechanical loads, and other mechanics-based risk factors using medical imaging as inputs. Its incorporation into clinical practice has the potential to improve diagnosis and treatment planning with low associated risks and costs. These methods have become available for medical applications mainly due to the continuing development of image-based kinematic techniques, the maturity of the associated theories describing cardiovascular function, and recent progress in computer science, modeling, and simulation engineering. Inverse method applications are multidisciplinary, requiring tailored solutions to the available clinical data, pathology of interest, and available computational resources. Herein, we review biomechanical modeling and simulation principles, methods of solving inverse problems, and techniques for image-based kinematic analysis. In the final section, the major advances in inverse modeling of human cardiovascular mechanics since its early development in the early 2000s are reviewed with emphasis on method-specific descriptions, results, and conclusions. We draw selected studies on healthy and diseased hearts, aortas, and pulmonary arteries achieved through the incorporation of tissue mechanics, hemodynamics, and fluid-structure interaction methods paired with patient-specific data acquired with medical imaging in inverse modeling approaches.
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Affiliation(s)
- Johane H. Bracamonte
- Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Sarah K. Saunders
- Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - John S. Wilson
- Department of Biomedical Engineering and Pauley Heart Center, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Uyen T. Truong
- Department of Pediatrics, School of Medicine, Children’s Hospital of Richmond at Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Joao S. Soares
- Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA 23284, USA
- Correspondence:
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Abstract
Scaffold-based tissue engineering requires a resorbable scaffold that can restore function and guide regeneration. Recent advances in material fabrication have expanded our control of compositional and architectural features to approach the complexity of native tissue. However, iterative scaffold design to balance multiple design targets toward optimizing regenerative performance remains both challenging and time-consuming. The number of design parameter combinations for scaffold manufacturing to achieve target properties is nearly limitless. Although a trial-and-error experimental approach may lead to a favorable scaffold design, the time and costs associated with such an approach are enormous. Computational optimization approaches are well suited to sample such a multidimensional design space and streamline the identification of target scaffold parameters for experimental evaluation. In this computational biomechanics approach, target fabrication parameters are identified by using a computational model to iterate across design parameter combinations (input) and predict the resulting graft properties (output). Herein, we describe the three key stages of this model-directed scaffold design: (1) model development, verification, and validation; (2) in silico optimization; and (3) model-directed scaffold fabrication and testing. Although there are several notable examples that have demonstrated the potential of this approach, additional accurate and physiologically appropriate computational simulations are needed to expand its utility across the field. In addition, continued advances in material fabrication are needed to provide the requisite control and resolution to produce the model-directed design. Finally, and most importantly, active collaboration between experts in materials science and computational modeling are critical to realize the full potential of this approach to accelerate scaffold development.
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Affiliation(s)
| | - Lucas H Timmins
- Department of Biomedical Engineering, The University of Utah, Salt Lake City, Utah 84112, United States.,Scientific Computing and Imaging Institute, The University of Utah, Salt Lake City, Utah 84112, United States
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30
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Wang M, Deng Y, Xie P, Tan J, Yang Y, Ouyang H, Zhao D, Huang G, Huang W. Optimal Design and Biomechanical Analysis of a Biomimetic Lightweight Design Plate for Distal Tibial Fractures: A Finite Element Analysis. Front Bioeng Biotechnol 2022; 10:820921. [PMID: 35265599 PMCID: PMC8901108 DOI: 10.3389/fbioe.2022.820921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/27/2022] [Indexed: 11/13/2022] Open
Abstract
The treatment of fractures of the distal tibia can be problematic due to the insubstantial soft-tissue covering this part of the anatomy. This study investigates a novel strategy for minimally invasive plate osteosynthesis of distal tibia fractures called bionic lightweight design plating. Following the structure of the animal trabecular bone, we utilized topological mathematical methods to redesign the material layout of the internal fixation device to fulfill the desired lightweight design within given boundary conditions. The results showed that this method can maintain the same stability of the construct as the original plate after a reduction in the original volume by 30%, and the differences in strain energy of plates and maximum node displacement of constructs between the constructs [RP construct vs. LP construct] were not statistically significant (p > 0.05). In the safety assessment of the constructs, the peak stress of plates between constructs was found to not be statistically significantly different under a doubled physiological load (p > 0.05). The average stress of the plates’ elements exceeding the allowable stress was analyzed, and no statistically significant differences were found between the two constructs under axial compression stress conditions (p > 0.05). The average stress of the plates’ elements in the redesigned plating construct under torsional stress conditions was 3.08% less than that of the locked plating construct (p < 0.05). Under the double physiological load condition, 89% of the elements of the plate in the redesigned plating construct and 85% of the elements of the plate in the locked plating construct were lower than the maximum safe stress of the plate, which was 410 MPa (secondary allowable stresses). That reminds us the topology optimization offer a possible way to improve the capacity of soft tissue protection while ensuring the safety of the RP construct by reducing the volume of the implants.
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Affiliation(s)
- Mian Wang
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
| | - Yuping Deng
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
- Department of Orthopedics and Traumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Pusheng Xie
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Guangdong Medical Innovation Platform for Translation of 3D Printing Application, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Jinchuan Tan
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Yang Yang
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Department of Orthopedics and Traumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Hanbin Ouyang
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Orthopaedic Center, Affiliated Hospital of Guangdong Medical University, Guangdong Medical University, Zhanjiang, China
| | - Dongliang Zhao
- Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Gang Huang
- Department of Orthopedics and Traumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- *Correspondence: Gang Huang, ; Wenhua Huang,
| | - Wenhua Huang
- National Key Discipline of Human Anatomy, Guangdong Provincial Key Laboratory of Medical Biomechanics, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
- Department of Orthopedics and Traumatology, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
- Guangdong Medical Innovation Platform for Translation of 3D Printing Application, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
- *Correspondence: Gang Huang, ; Wenhua Huang,
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31
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Blum KM, Zbinden JC, Ramachandra AB, Lindsey SE, Szafron JM, Reinhardt JW, Heitkemper M, Best CA, Mirhaidari GJM, Chang YC, Ulziibayar A, Kelly J, Shah KV, Drews JD, Zakko J, Miyamoto S, Matsuzaki Y, Iwaki R, Ahmad H, Daulton R, Musgrave D, Wiet MG, Heuer E, Lawson E, Schwarz E, McDermott MR, Krishnamurthy R, Krishnamurthy R, Hor K, Armstrong AK, Boe BA, Berman DP, Trask AJ, Humphrey JD, Marsden AL, Shinoka T, Breuer CK. Tissue engineered vascular grafts transform into autologous neovessels capable of native function and growth. COMMUNICATIONS MEDICINE 2022; 2:3. [PMID: 35603301 PMCID: PMC9053249 DOI: 10.1038/s43856-021-00063-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 11/30/2021] [Indexed: 11/09/2022] Open
Abstract
Background Tissue-engineered vascular grafts (TEVGs) have the potential to advance the surgical management of infants and children requiring congenital heart surgery by creating functional vascular conduits with growth capacity. Methods Herein, we used an integrative computational-experimental approach to elucidate the natural history of neovessel formation in a large animal preclinical model; combining an in vitro accelerated degradation study with mechanical testing, large animal implantation studies with in vivo imaging and histology, and data-informed computational growth and remodeling models. Results Our findings demonstrate that the structural integrity of the polymeric scaffold is lost over the first 26 weeks in vivo, while polymeric fragments persist for up to 52 weeks. Our models predict that early neotissue accumulation is driven primarily by inflammatory processes in response to the implanted polymeric scaffold, but that turnover becomes progressively mechano-mediated as the scaffold degrades. Using a lamb model, we confirm that early neotissue formation results primarily from the foreign body reaction induced by the scaffold, resulting in an early period of dynamic remodeling characterized by transient TEVG narrowing. As the scaffold degrades, mechano-mediated neotissue remodeling becomes dominant around 26 weeks. After the scaffold degrades completely, the resulting neovessel undergoes growth and remodeling that mimicks native vessel behavior, including biological growth capacity, further supported by fluid-structure interaction simulations providing detailed hemodynamic and wall stress information. Conclusions These findings provide insights into TEVG remodeling, and have important implications for clinical use and future development of TEVGs for children with congenital heart disease.
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Affiliation(s)
- Kevin M. Blum
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210 USA
| | - Jacob C. Zbinden
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210 USA
| | | | - Stephanie E. Lindsey
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA 94305 USA
- Institute for Computational and Mathematical Engineering (ICME), Stanford University, Stanford, CA 94305 USA
| | - Jason M. Szafron
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520 USA
| | - James W. Reinhardt
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Megan Heitkemper
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Cameron A. Best
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- The Ohio State University College of Medicine, Columbus, OH 43210 USA
| | - Gabriel J. M. Mirhaidari
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Yu-Chun Chang
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Anudari Ulziibayar
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - John Kelly
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Kejal V. Shah
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Joseph D. Drews
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, OH 43210 USA
| | - Jason Zakko
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Surgery, The Ohio State University Wexner Medical Center, Columbus, OH 43210 USA
| | - Shinka Miyamoto
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Cardiovascular Surgery at Tokyo Women’s Medical University, Tokyo, Japan
| | - Yuichi Matsuzaki
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Ryuma Iwaki
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Hira Ahmad
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Pediatric Colorectal and Pelvic Reconstructive Surgery, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Robbie Daulton
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- University of Cincinnati College of Medicine 3230 Eden Ave, Cincinnati, OH 45267 USA
| | - Drew Musgrave
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Matthew G. Wiet
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- The Ohio State University College of Medicine, Columbus, OH 43210 USA
| | - Eric Heuer
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Emily Lawson
- The Ohio State University College of Medicine, Columbus, OH 43210 USA
| | - Erica Schwarz
- Department of Bioengineering, Stanford University, Stanford, CA 94304 USA
| | - Michael R. McDermott
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Rajesh Krishnamurthy
- Department of Radiology, Nationwide Children’s Hospital, Columbus, Ohio 43205 USA
| | | | - Kan Hor
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Aimee K. Armstrong
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Brian A. Boe
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Darren P. Berman
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
| | - Aaron J. Trask
- Center for Cardiovascular Research, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210 USA
| | - Jay D. Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520 USA
| | - Alison L. Marsden
- Institute for Computational and Mathematical Engineering (ICME), Stanford University, Stanford, CA 94305 USA
- Department of Bioengineering, Stanford University, Stanford, CA 94304 USA
| | - Toshiharu Shinoka
- The Heart Center, Nationwide Children’s Hospital, Columbus, OH 43205 USA
- Department of Cardiothoracic Surgery, The Ohio State University College of Medicine, Columbus, OH 43205 USA
| | - Christopher K. Breuer
- Center for Regenerative Medicine, Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH 43205 USA
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Corti A, Colombo M, Migliavacca F, Rodriguez Matas JF, Casarin S, Chiastra C. Multiscale Computational Modeling of Vascular Adaptation: A Systems Biology Approach Using Agent-Based Models. Front Bioeng Biotechnol 2021; 9:744560. [PMID: 34796166 PMCID: PMC8593007 DOI: 10.3389/fbioe.2021.744560] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/04/2021] [Indexed: 12/20/2022] Open
Abstract
The widespread incidence of cardiovascular diseases and associated mortality and morbidity, along with the advent of powerful computational resources, have fostered an extensive research in computational modeling of vascular pathophysiology field and promoted in-silico models as a support for biomedical research. Given the multiscale nature of biological systems, the integration of phenomena at different spatial and temporal scales has emerged to be essential in capturing mechanobiological mechanisms underlying vascular adaptation processes. In this regard, agent-based models have demonstrated to successfully embed the systems biology principles and capture the emergent behavior of cellular systems under different pathophysiological conditions. Furthermore, through their modular structure, agent-based models are suitable to be integrated with continuum-based models within a multiscale framework that can link the molecular pathways to the cell and tissue levels. This can allow improving existing therapies and/or developing new therapeutic strategies. The present review examines the multiscale computational frameworks of vascular adaptation with an emphasis on the integration of agent-based approaches with continuum models to describe vascular pathophysiology in a systems biology perspective. The state-of-the-art highlights the current gaps and limitations in the field, thus shedding light on new areas to be explored that may become the future research focus. The inclusion of molecular intracellular pathways (e.g., genomics or proteomics) within the multiscale agent-based modeling frameworks will certainly provide a great contribution to the promising personalized medicine. Efforts will be also needed to address the challenges encountered for the verification, uncertainty quantification, calibration and validation of these multiscale frameworks.
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Affiliation(s)
- Anna Corti
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy
| | - Monika Colombo
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy.,Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Switzerland
| | - Francesco Migliavacca
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy
| | - Jose Felix Rodriguez Matas
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy
| | - Stefano Casarin
- Department of Surgery, Houston Methodist Hospital, Houston, TX, United States.,Center for Computational Surgery, Houston Methodist Research Institute, Houston, TX, United States.,Houston Methodist Academic Institute, Houston, TX, United States
| | - Claudio Chiastra
- Laboratory of Biological Structure Mechanics (LaBS), Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy.,PoliToMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
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33
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Weiss D, Latorre M, Rego BV, Cavinato C, Tanski BJ, Berman AG, Goergen CJ, Humphrey JD. Biomechanical consequences of compromised elastic fiber integrity and matrix cross-linking on abdominal aortic aneurysmal enlargement. Acta Biomater 2021; 134:422-434. [PMID: 34332103 DOI: 10.1016/j.actbio.2021.07.059] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/07/2021] [Accepted: 07/23/2021] [Indexed: 12/25/2022]
Abstract
Abdominal aortic aneurysms (AAAs) are characterized histopathologically by compromised elastic fiber integrity, lost smooth muscle cells or their function, and remodeled collagen. We used a recently introduced mouse model of AAAs that combines enzymatic degradation of elastic fibers and blocking of lysyl oxidase, and thus matrix cross-linking, to study progressive dilatation of the infrarenal abdominal aorta, including development of intraluminal thrombus. We quantified changes in biomaterial properties and biomechanical functionality within the aneurysmal segment as a function of time of enlargement and degree of thrombosis. Towards this end, we combined multi-modality imaging with state-of-the art biomechanical testing and histology to quantify regional heterogeneities for the first time and we used a computational model of arterial growth and remodeling to test multiple hypotheses, suggested by the data, regarding the degree of lost elastin, accumulation of glycosaminoglycans, and rates of collagen turnover. We found that standard histopathological findings can be misleading, while combining advanced experimental and computational methods revealed that glycosaminoglycan accumulation is pathologic, not adaptive, and that heightened collagen deposition is ineffective if not cross-linked. In conclusion, loss of elastic fiber integrity can be a strong initiator of aortic aneurysms, but it is the rate and effectiveness of fibrillar collagen remodeling that dictates enlargement. STATEMENT OF SIGNIFICANCE: Precise mechanisms by which abdominal aortic aneurysms enlarge remain unclear, but a recent elastase plus β-aminopropionitrile mouse model provides new insight into disease progression. As in the human condition, the aortic degeneration and adverse remodeling are highly heterogeneous in this model. Our multi-modality experiments quantify and contrast the heterogeneities in geometry and biomaterial properties, and our computational modeling shows that standard histopathology can be misleading. Neither accumulating glycosaminoglycans nor frustrated collagen synthesis slow disease progression, thus highlighting the importance of stimulating adaptive collagen remodeling to limit lesion enlargement.
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Affiliation(s)
- D Weiss
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - M Latorre
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - B V Rego
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - C Cavinato
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - B J Tanski
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - A G Berman
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - C J Goergen
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
| | - J D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA.
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Sharifi H, Mann CK, Rockward AL, Mehri M, Mojumder J, Lee LC, Campbell KS, Wenk JF. Multiscale simulations of left ventricular growth and remodeling. Biophys Rev 2021; 13:729-746. [PMID: 34777616 PMCID: PMC8555068 DOI: 10.1007/s12551-021-00826-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 08/05/2021] [Indexed: 02/07/2023] Open
Abstract
Cardiomyocytes can adapt their size, shape, and orientation in response to altered biomechanical or biochemical stimuli. The process by which the heart undergoes structural changes-affecting both geometry and material properties-in response to altered ventricular loading, altered hormonal levels, or mutant sarcomeric proteins is broadly known as cardiac growth and remodeling (G&R). Although it is likely that cardiac G&R initially occurs as an adaptive response of the heart to the underlying stimuli, prolonged pathological changes can lead to increased risk of atrial fibrillation, heart failure, and sudden death. During the past few decades, computational models have been extensively used to investigate the mechanisms of cardiac G&R, as a complement to experimental measurements. These models have provided an opportunity to quantitatively study the relationships between the underlying stimuli (primarily mechanical) and the adverse outcomes of cardiac G&R, i.e., alterations in ventricular size and function. State-of-the-art computational models have shown promise in predicting the progression of cardiac G&R. However, there are still limitations that need to be addressed in future works to advance the field. In this review, we first outline the current state of computational models of cardiac growth and myofiber remodeling. Then, we discuss the potential limitations of current models of cardiac G&R that need to be addressed before they can be utilized in clinical care. Finally, we briefly discuss the next feasible steps and future directions that could advance the field of cardiac G&R.
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Affiliation(s)
- Hossein Sharifi
- Department of Mechanical Engineering, University of Kentucky, 269 Ralph G. Anderson Building, Lexington, KY 40506-0503 USA
| | - Charles K. Mann
- Department of Mechanical Engineering, University of Kentucky, 269 Ralph G. Anderson Building, Lexington, KY 40506-0503 USA
| | - Alexus L. Rockward
- Department of Mechanical Engineering, University of Kentucky, 269 Ralph G. Anderson Building, Lexington, KY 40506-0503 USA
| | - Mohammad Mehri
- Department of Mechanical Engineering, University of Kentucky, 269 Ralph G. Anderson Building, Lexington, KY 40506-0503 USA
| | - Joy Mojumder
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI USA
| | - Lik-Chuan Lee
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI USA
| | - Kenneth S. Campbell
- Department of Physiology & Division of Cardiovascular Medicine, University of Kentucky, Lexington, KY USA
| | - Jonathan F. Wenk
- Department of Mechanical Engineering, University of Kentucky, 269 Ralph G. Anderson Building, Lexington, KY 40506-0503 USA
- Department of Surgery, University of Kentucky, Lexington, KY USA
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