1
|
Xu KW, Liu XL, He B, Gao Q. Numerical methods for hemolysis and thrombus evaluation in the percutaneous ventricular assist device. Artif Organs 2024; 48:504-513. [PMID: 38146899 DOI: 10.1111/aor.14701] [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: 07/11/2023] [Revised: 11/03/2023] [Accepted: 12/12/2023] [Indexed: 12/27/2023]
Abstract
BACKGROUND A percutaneous ventricular assist device (pVAD) is an effective method to treat heart failure, but its complications, mainly hemolysis and thrombus formation, cannot be ignored. Accurate evaluation of hemolysis and thrombus formation in pVAD is essential to guide the development of pVAD and reduce the incidence of complications. METHODS This study optimized the numerical model to predict hemolysis and thrombus formation in pVAD. The hemolysis model is based on the power law function, and the multi-component thrombus prediction model is improved by introducing the von Willebrand factor. RESULTS The error between the numerical simulation and the hydraulic performance experiment is within 5%. The numerical results of hemolysis are in good agreement with those of in vitro experiments. Meanwhile, the thrombus location predicted by the numerical model is the same as that found in the in vivo experiment. CONCLUSION The numerical model suggested in this study may therefore accurately assess the possible hemolytic and thrombotic dangers in pVAD, making it an effective tool to support the development of pVAD.
Collapse
Affiliation(s)
- Ke-Wei Xu
- State Key Laboratory of Transvascular Implantation Devices, Zhejiang University, Hangzhou, China
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, China
| | - Xing-Li Liu
- Zhejiang Diyuan Medical Instrument Co., Ltd., Hangzhou, China
| | - Bo He
- Zhejiang Diyuan Medical Instrument Co., Ltd., Hangzhou, China
| | - Qi Gao
- State Key Laboratory of Transvascular Implantation Devices, Zhejiang University, Hangzhou, China
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, China
| |
Collapse
|
2
|
Su B, Palahnuk H, Harbaugh T, Rizk E, Hazard W, Chan A, Bernstein J, Weinsaft JW, Manning KB. Numerical Study on the Impact of Central Venous Catheter Placement on Blood Flow in the Cavo-Atrial Junction. Ann Biomed Eng 2024; 52:1378-1392. [PMID: 38407724 DOI: 10.1007/s10439-024-03463-7] [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: 08/21/2023] [Accepted: 01/30/2024] [Indexed: 02/27/2024]
Abstract
An in silico study is performed to investigate fluid dynamic effects of central venous catheter (CVC) placement within patient-specific cavo-atrial junctions. Prior studies show the CVC infusing a liquid, but this study focuses on the placement without any liquid emerging from the CVC. A 7 or 15-French double-lumen CVC is placed virtually in two patient-specific models; the CVC tip location is altered to understand its effect on the venous flow field. Results show that the CVC impact is trivial on flow in the superior vena cava when the catheter-to-vein ratio ranges from 0.15 to 0.33. Results further demonstrate that when the CVC tip is directly in the right atrium, flow vortices in the right atrium result in elevated wall shear stress near the tip hole. A recirculation region characterizes a spatially variable flow field inside the CVC side hole. Furthermore, flow stagnation is present near the internal side hole corners but an elevated wall shear stress near the curvature of the side hole's exit. These results suggest that optimal CVC tip location is within the superior vena cava, so as to lower the potential for platelet activation due to elevated shear stresses and that CVC geometry and location depth in the central vein significantly influences the local CVC fluid dynamics. A thrombosis model also shows thrombus formation at the side hole and tip hole. After modifying the catheter design, the hemodynamics change, which alter thrombus formation. Future studies are warranted to study CVC design and placement location in an effort to minimize CVC-induced thrombosis incidence.
Collapse
Affiliation(s)
- Boyang Su
- Department of Biomedical Engineering, The Pennsylvania State University, 122 Chemical and Biomedical Engineering Building, University Park, PA, 16802-4400, USA
| | - Hannah Palahnuk
- Department of Biomedical Engineering, The Pennsylvania State University, 122 Chemical and Biomedical Engineering Building, University Park, PA, 16802-4400, USA
| | - Thaddeus Harbaugh
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - Elias Rizk
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - Will Hazard
- Department of Neurosurgery, Penn State College of Medicine, Hershey, PA, USA
| | - Angel Chan
- Department of Medicine (Cardiology), Weill Cornell College, New York, NY, USA
- Department of Medicine (Cardiology), Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Jonathan Bernstein
- Division of Pediatric Hematology/Oncology, Penn State Hershey Children's Hospital, Hershey, PA, USA
| | - Jonathan W Weinsaft
- Department of Medicine (Cardiology), Weill Cornell College, New York, NY, USA
- Department of Medicine (Cardiology), Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Department of Radiology (Cardiothoracic Imaging), Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Keefe B Manning
- Department of Biomedical Engineering, The Pennsylvania State University, 122 Chemical and Biomedical Engineering Building, University Park, PA, 16802-4400, USA.
- Department of Surgery, Penn State College of Medicine, Hershey, PA, USA.
| |
Collapse
|
3
|
He W, Karmakar A, Kang J, Rowlands G, Schirmacher S, Méndez-Rojano R, Antaki J. In Vitro and In Silico Characterization of the Aggregation of Thrombi on Textured Ventricular Cannula. Ann Biomed Eng 2024:10.1007/s10439-024-03504-1. [PMID: 38679660 DOI: 10.1007/s10439-024-03504-1] [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: 11/07/2023] [Accepted: 03/25/2024] [Indexed: 05/01/2024]
Abstract
The unacceptably high stroke rate associated with HeartMate 3 ventricular assist device (VAD) without signs of adherent pump thrombosis is hypothesized to be the result of the emboli produced by the inflow cannula, that are ingested and ejected from the pump. This in vitro and numerical study aimed to emulate the surface features and supraphysiological shear of a ventricular cannula to provide insight into their effect on thrombogenesis. Human whole blood was perfused at calibrated flow rates in a microfluidic channel to achieve shear rates 1000-7500 s-1, comparable to that experienced on the cannula. The channel contained periodic teeth representative of the rough sintered surface of the HeartMate 3 cannula. The deposition of fluorescently labeled platelets was visualized in real time and analyzed with a custom entity tracking algorithm. Numerical simulations of a multi-constituent thrombosis model were performed to simulate laminar blood flow in the channel. The sustained growth of adherent platelets was observed in all shear conditions ( p < 0.05). However, the greatest deposition was observed at the lower shear rates. The location of deposition with respect to the microfluidic teeth was also found to vary with shear rate. This was confirmed by CFD simulation. The entity tracking algorithm revealed the spatial variation of instances of embolic events. This result suggests that the sintered surface of the ventricular cannula may engender unstable thrombi with a greater likelihood of embolization at supraphysiological shear rates.
Collapse
Affiliation(s)
- Wenxuan He
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Abhishek Karmakar
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Junhyuk Kang
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Grant Rowlands
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Samuel Schirmacher
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | | | - James Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA.
| |
Collapse
|
4
|
Sveshnikova AN, Shibeko AM, Kovalenko TA, Panteleev MA. Kinetics and regulation of coagulation factor X activation by intrinsic tenase on phospholipid membranes. J Theor Biol 2024; 582:111757. [PMID: 38336240 DOI: 10.1016/j.jtbi.2024.111757] [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: 08/28/2023] [Revised: 12/13/2023] [Accepted: 01/31/2024] [Indexed: 02/12/2024]
Abstract
BACKGROUND Factor X activation by the phospholipid-bound intrinsic tenase complex is a critical membrane-dependent reaction of blood coagulation. Its regulation mechanisms are unclear, and a number of questions regarding diffusional limitation, pathways of assembly and substrate delivery remain open. METHODS We develop and analyze here a detailed mechanism-driven computer model of intrinsic tenase on phospholipid surfaces. Three-dimensional reaction-diffusion-advection and stochastic simulations were used where appropriate. RESULTS Dynamics of the system was predominantly non-stationary under physiological conditions. In order to describe experimental data, we had to assume both membrane-dependent and solution-dependent delivery of the substrate. The former pathway dominated at low cofactor concentration, while the latter became important at low phospholipid concentration. Factor VIIIa-factor X complex formation was the major pathway of the complex assembly, and the model predicted high affinity for their lipid-dependent interaction. Although the model predicted formation of the diffusion-limited layer of substrate for some conditions, the effects of this limitation on the fXa production were small. Flow accelerated fXa production in a flow reactor model by bringing in fIXa and fVIIIa rather than fX. CONCLUSIONS This analysis suggests a concept of intrinsic tenase that is non-stationary, employs several pathways of substrate delivery depending on the conditions, and is not particularly limited by diffusion of the substrate.
Collapse
Affiliation(s)
- Anastasia N Sveshnikova
- National Medical and Research Center of Pediatric Hematology, Oncology and Immunology Named After Dmitry Rogachev, 1 Samory Mashela St, Moscow, 117198, Russia; Faculty of Fundamental Physico-Chemical Engineering, Lomonosov Moscow State University, 1/51 Leninskie Gory, 119991 Moscow, Russia; Department of Normal Physiology, Sechenov First Moscow State Medical University, 8/2 Trubetskaya St., 119991 Moscow, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, 4 Kosygina St, Moscow, 119991, Russia
| | - Alexey M Shibeko
- National Medical and Research Center of Pediatric Hematology, Oncology and Immunology Named After Dmitry Rogachev, 1 Samory Mashela St, Moscow, 117198, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, 4 Kosygina St, Moscow, 119991, Russia
| | - Tatiana A Kovalenko
- National Medical and Research Center of Pediatric Hematology, Oncology and Immunology Named After Dmitry Rogachev, 1 Samory Mashela St, Moscow, 117198, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, 4 Kosygina St, Moscow, 119991, Russia
| | - Mikhail A Panteleev
- National Medical and Research Center of Pediatric Hematology, Oncology and Immunology Named After Dmitry Rogachev, 1 Samory Mashela St, Moscow, 117198, Russia; Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, 4 Kosygina St, Moscow, 119991, Russia; Faculty of Physics, Lomonosov Moscow State University, 1/2 Leninskie Gory, Moscow, 119991, Russia.
| |
Collapse
|
5
|
Vu V, Rossini L, del Alamo JC, Dembitsky W, Gray RA, May-Newman K. Benchtop Models of Patient-Specific Intraventricular Flow During Heart Failure and LVAD Support. J Biomech Eng 2023; 145:111010. [PMID: 37565996 PMCID: PMC10777504 DOI: 10.1115/1.4063147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 08/01/2023] [Accepted: 08/03/2023] [Indexed: 08/12/2023]
Abstract
The characterization of intraventricular flow is critical to evaluate the efficiency of fluid transport and potential thromboembolic risk but challenging to measure directly in advanced heart failure (HF) patients with left ventricular assist device (LVAD) support. The study aims to validate an in-house mock loop (ML) by simulating specific conditions of HF patients with normal and prosthetic mitral valves (MV) and LVAD patients with small and dilated left ventricle volumes, then comparing the flow-related indices result of vortex parameters, residence time (RT), and shear-activation potential (SAP). Patient-specific inputs for the ML studies included heart rate, end-diastolic and end-systolic volumes, ejection fraction, aortic pressure, E/A ratio, and LVAD speed. The ML effectively replicated vortex development and circulation patterns, as well as RT, particularly for HF patient cases. The LVAD velocity fields reflected altered flow paths, in which all or most incoming blood formed a dominant stream directing flow straight from the mitral valve to the apex. RT estimation of patient and ML compared well for all conditions, but SAP was substantially higher in the LVAD cases of the ML. The benchtop system generated comparable and reproducible hemodynamics and fluid dynamics for patient-specific conditions, validating its reliability and clinical relevance. This study demonstrated that ML is a suitable platform to investigate the fluid dynamics of HF and LVAD patients and can be utilized to investigate heart-implant interactions.
Collapse
Affiliation(s)
- Vi Vu
- Bioengineering Program, Department of Mechanical Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182;Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993
| | - Lorenzo Rossini
- Mechanical and Aerospace Engineering Department, University of California, San Diego 9500 Gilman Drive, La Jolla, CA 92093
| | - Juan C. del Alamo
- Center for Cardiovascular Biology & Mechanical Engineering Department, University of Washington, 1400 NE Campus Parkway, Seattle, WA 98195
| | - Walter Dembitsky
- Cardiothoracic Surgery, Mechanical Assist Program, Sharp Memorial Hospital, San Diego 7901 Frost Street, San Diego, CA 92123
| | - Richard A. Gray
- Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993
| | - Karen May-Newman
- Bioengineering Program, Department of Mechanical Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182
| |
Collapse
|
6
|
Montgomery D, Municchi F, Leiderman K. clotFoam: An Open-Source Framework to Simulate Blood Clot Formation Under Arterial Flow. ARXIV 2023:arXiv:2304.09180v3. [PMID: 37131873 PMCID: PMC10153289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Blood clotting involves the coupled processes of platelet aggregation and coagulation. Simulating clotting under flow in complex geometries is challenging due to multiple temporal and spatial scales and high computational cost. clotFoam is an open-source software developed in OpenFOAM that employs a continuum model of platelet advection, diffusion, and aggregation in a dynamic fluid environment and a simplified coagulation model with proteins that advect, diffuse, and react within the fluid and with wall-bound species through reactive boundary conditions. Our framework provides the foundation on which one can build more complex models and perform reliable simulations in almost any computational domain.
Collapse
Affiliation(s)
- David Montgomery
- Department of Applied Mathematics and Statistics, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, United States of America
| | - Federico Municchi
- Department of Mechanical Engineering, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, United States of America
| | - Karin Leiderman
- Department of Mathematics, University of North Carolina at Chapel Hill, 216 Lenoir Dr, Chapel Hill, NC 27599, United States of America
- Computational Medicine Program, University of North Carolina at Chapel Hill, 216 Lenoir Dr, Chapel Hill, NC 27599, United States of America
| |
Collapse
|
7
|
Belyaev AV, Kushchenko YK. Biomechanical activation of blood platelets via adhesion to von Willebrand factor studied with mesoscopic simulations. Biomech Model Mechanobiol 2023; 22:785-808. [PMID: 36627458 PMCID: PMC9838538 DOI: 10.1007/s10237-022-01681-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023]
Abstract
Platelet adhesion and activation are essential initial processes of arterial and microvascular hemostasis, where high hydrodynamic forces from the bloodflow impede coagulation. The process relies on von Willebrand factor (VWF)-a linear multimeric protein of blood plasma plays a pivotal role in mechanochemical regulation of shear-induced platelet aggregation (SIPA). Adhesive interactions between VWF and glycoprotein receptors GPIb are crucial for platelet recruitment under high shear stress in fluid. Recent advances in experimental studies revealed that mechanical tension on the extracellular part of GPIb may trigger a cascade of biochemical reactions in platelets leading to activation of integrins [Formula: see text] (also known as GPIIb/IIIa) and strengthening of the adhesion. The present paper is aimed at investigation of this process by three-dimensional computer simulations of platelet adhesion to surface-grafted VWF multimers in pressure-driven flow of platelet-rich plasma. The simulations demonstrate that GPIb-mediated mechanotransduction is a feasible way of platelet activation and stabilization of platelet aggregates under high shear stress. Quantitative understanding of mechanochemical processes involved in SIPA would potentially promote the discovery of new anti-platelet medication and the development of multiscale numerical models of platelet thrombosis and hemostasis.
Collapse
Affiliation(s)
- Aleksey V. Belyaev
- grid.14476.300000 0001 2342 9668Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskiye Gory, Moscow, Russia 119991
| | - Yulia K. Kushchenko
- grid.14476.300000 0001 2342 9668Faculty of Physics, M.V. Lomonosov Moscow State University, 1-2 Leninskiye Gory, Moscow, Russia 119991
| |
Collapse
|
8
|
Zhussupbekov M, Méndez Rojano R, Wu WT, Antaki JF. von Willebrand factor unfolding mediates platelet deposition in a model of high-shear thrombosis. Biophys J 2022; 121:4033-4047. [PMID: 36196057 PMCID: PMC9675031 DOI: 10.1016/j.bpj.2022.09.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/21/2022] [Accepted: 09/27/2022] [Indexed: 11/30/2022] Open
Abstract
Thrombosis under high-shear conditions is mediated by the mechanosensitive blood glycoprotein von Willebrand factor (vWF). vWF unfolds in response to strong flow gradients and facilitates rapid recruitment of platelets in flowing blood. While the thrombogenic effect of vWF is well recognized, its conformational response in complex flows has largely been omitted from numerical models of thrombosis. We recently presented a continuum model for the unfolding of vWF, where we represented vWF transport and its flow-induced conformational change using convection-diffusion-reaction equations. Here, we incorporate the vWF component into our multi-constituent model of thrombosis, where the local concentration of stretched vWF amplifies the deposition rate of free-flowing platelets and reduces the shear cleaning of deposited platelets. We validate the model using three benchmarks: in vitro model of atherothrombosis, a stagnation point flow, and the PFA-100, a clinical blood test commonly used for screening for von Willebrand disease (vWD). The simulations reproduced the key aspects of vWF-mediated thrombosis observed in these experiments, such as the thrombus location, thrombus growth dynamics, and the effect of blocking platelet-vWF interactions. The PFA-100 simulations closely matched the reported occlusion times for normal blood and several hemostatic deficiencies, namely, thrombocytopenia, vWD type 1, and vWD type 3. Overall, this multi-constituent model of thrombosis enables macro-scale 3D simulations of thrombus formation in complex geometries over a wide range of shear rates and accounts for qualitative and quantitative hemostatic deficiencies in patient blood.
Collapse
Affiliation(s)
- Mansur Zhussupbekov
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York
| | | | - Wei-Tao Wu
- Department of Aerospace Science and Technology, Nanjing University of Science and Technology, Nanjing, China
| | - James F Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York.
| |
Collapse
|
9
|
Wang Y, Luan J, Luo K, Fan J, Zhu T. Model reduction of coagulation cascade based on genetic algorithm. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2022; 38:e3652. [PMID: 36167948 DOI: 10.1002/cnm.3652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 08/18/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
Fibrin is an important product of the coagulation cascade, and plays an eminent role in platelet stabilization. Since coagulation cascade models typically involve the reaction kinetics of dozens of proteins, which will incur burdensome computational costs when coupled to blood flow in complex geometries, researchers often ignore this process when constructing thrombosis models. However, previous studies have shown that fundamental aspects of coagulation can be reproduced with simpler models, which motivated us to obtain a reduced-order model of fibrin generation through a systematic approach. Therefore, we introduced a semi-automatic framework to perform model-reduction of cascade reactions in this study, which consisted of two processes. Specifically, the retained protein species and cascade reactions were determined based on published studies and simulation results from the full cascade model, while the optimal reaction rates for the new cascade network were determined using a genetic algorithm. The framework has been applied to a 19-species coagulation model that triggers fibrin generation in internal fields via reactive boundaries, and a 10-species reduced-order model was obtained to reproduce the kinetics of fibrinogenesis in the full cascade model at different boundary tissue factor concentrations. This reduced-order model of fibrinogenesis would be valuable for thrombosis modeling that considers both the coagulation cascade and platelet activity. Furthermore, the framework proposed herein can also be applied to the reductions of other cascade reaction models.
Collapse
Affiliation(s)
- Yan Wang
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| | - Jingyang Luan
- Department of Vascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Kun Luo
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| | - Jianren Fan
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| | - Ting Zhu
- Department of Vascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
10
|
Méndez Rojano R, Lai A, Zhussupbekov M, Burgreen GW, Cook K, Antaki JF. A fibrin enhanced thrombosis model for medical devices operating at low shear regimes or large surface areas. PLoS Comput Biol 2022; 18:e1010277. [PMID: 36190991 PMCID: PMC9560616 DOI: 10.1371/journal.pcbi.1010277] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 10/13/2022] [Accepted: 09/15/2022] [Indexed: 11/06/2022] Open
Abstract
Over the past decade, much of the development of computational models of device-related thrombosis has focused on platelet activity. While those models have been successful in predicting thrombus formation in medical devices operating at high shear rates (> 5000 s−1), they cannot be directly applied to low-shear devices, such as blood oxygenators and catheters, where emerging information suggest that fibrin formation is the predominant mechanism of clotting and platelet activity plays a secondary role. In the current work, we augment an existing platelet-based model of thrombosis with a partial model of the coagulation cascade that includes contact activation of factor XII and fibrin production. To calibrate the model, we simulate a backward-facing-step flow channel that has been extensively characterized in-vitro. Next, we perform blood perfusion experiments through a microfluidic chamber mimicking a hollow fiber membrane oxygenator and validate the model against these observations. The simulation results closely match the time evolution of the thrombus height and length in the backward-facing-step experiment. Application of the model to the microfluidic hollow fiber bundle chamber capture both gross features such as the increasing clotting trend towards the outlet of the chamber, as well as finer local features such as the structure of fibrin around individual hollow fibers. Our results are in line with recent findings that suggest fibrin production, through contact activation of factor XII, drives the thrombus formation in medical devices operating at low shear rates with large surface area to volume ratios. Patients treated with blood-contacting medical devices suffer from clotting complications. Over the past decades, a great effort has been made to develop computational tools to predict and prevent clot formation in these devices. However, most models have focused on platelet activity and neglected other important parts of the problem such as the coagulation cascade reactions that lead to fibrin formation. In the current work, we incorporate this missing element into a well-established and validated model for platelet activity. We then use this novel approach to predict thrombus formation in two experimental configurations. Our results confirm that to accurately predict the clotting process in devices where surface area to volume ratios are large and flow velocity and shear stresses remain low, coagulation reactions and subsequent fibrin formation must be considered. This new model could have great implications for the design and optimization of medical devices such as blood oxygenators. In the long term, the model could evolve into a functional tool to inform anticoagulation therapies for these patients.
Collapse
Affiliation(s)
- Rodrigo Méndez Rojano
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York, United States of America
- * E-mail:
| | - Angela Lai
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Mansur Zhussupbekov
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York, United States of America
| | - Greg W. Burgreen
- Center for Advanced Vehicular Systems, Mississippi State University, Starkville, Mississippi, United States of America
| | - Keith Cook
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - James F. Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York, United States of America
| |
Collapse
|
11
|
Li Y, Wang H, Xi Y, Sun A, Deng X, Chen Z, Fan Y. A New Mathematical Numerical Model to Evaluate the Risk of Thrombosis in Three Clinical Ventricular Assist Devices. Bioengineering (Basel) 2022; 9:bioengineering9060235. [PMID: 35735478 PMCID: PMC9219778 DOI: 10.3390/bioengineering9060235] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 05/17/2022] [Accepted: 05/25/2022] [Indexed: 11/24/2022] Open
Abstract
(1) Background: Thrombosis is the main complication in patients supported with ventricular assist devices (VAD). Models that accurately predict the risk of thrombus formation in VADs are still lacking. When VADs are clinically assisted, their complex geometric configuration and high rotating speed inevitably generate complex flow fields and high shear stress. These non-physiological factors can damage blood cells and proteins, release coagulant factors and trigger thrombosis. In this study, a more accurate model for thrombus assessment was constructed by integrating parameters such as shear stress, residence time and coagulant factors, so as to accurately assess the probability of thrombosis in three clinical VADs. (2) Methods: A mathematical model was constructed to assess platelet activation and thrombosis within VADs. By solving the transport equation, the influence of various factors such as shear stress, residence time and coagulation factors on platelet activation was considered. The diffusion equation was applied to determine the role of activated platelets and substance deposition on thrombus formation. The momentum equation was introduced to describe the obstruction to blood flow when thrombus is formed, and finally a more comprehensive and accurate model for thrombus assessment in patients with VAD was obtained. Numerical simulations of three clinically VADs (CH-VAD, HVAD and HMII) were performed using this model. The simulation results were compared with experimental data on platelet activation caused by the three VADs. The simulated thrombogenic potential in different regions of MHII was compared with the frequency of thrombosis occurring in the regions in clinic. The regions of high thrombotic risk for HVAD and HMII observed in experiments were compared with the regions predicted by simulation. (3) Results: It was found that the percentage of activated platelets within the VAD obtained by solving the thrombosis model developed in this study was in high agreement with the experimental data (r² = 0.984), the likelihood of thrombosis in the regions of the simulation showed excellent correlation with the clinical statistics (r² = 0.994), and the regions of high thrombotic risk predicted by the simulation were consistent with the experimental results. Further study revealed that the three clinical VADs (CH-VAD, HVAD and HMII) were prone to thrombus formation in the inner side of the secondary flow passage, the clearance between cone and impeller, and the corner region of the inlet pipe, respectively. The risk of platelet activation and thrombus formation for the three VADs was low to high for CH-VAD, HVAD, and HM II, respectively. (4) Conclusions: In this study, a more comprehensive and accurate thrombosis model was constructed by combining parameters such as shear stress, residence time, and coagulation factors. Simulation results of thrombotic risk received with this model showed excellent correlation with experimental and clinical data. It is important for determining the degree of platelet activation in VAD and identifying regions prone to thrombus formation, as well as guiding the optimal design of VAD and clinical treatment.
Collapse
|
12
|
Hernandez JL, Woodrow KA. Medical Applications of Porous Biomaterials: Features of Porosity and Tissue-Specific Implications for Biocompatibility. Adv Healthc Mater 2022; 11:e2102087. [PMID: 35137550 PMCID: PMC9081257 DOI: 10.1002/adhm.202102087] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/17/2021] [Indexed: 12/14/2022]
Abstract
Porosity is an important material feature commonly employed in implants and tissue scaffolds. The presence of material voids permits the infiltration of cells, mechanical compliance, and outward diffusion of pharmaceutical agents. Various studies have confirmed that porosity indeed promotes favorable tissue responses, including minimal fibrous encapsulation during the foreign body reaction (FBR). However, increased biofilm formation and calcification is also described to arise due to biomaterial porosity. Additionally, the relevance of host responses like the FBR, infection, calcification, and thrombosis are dependent on tissue location and specific tissue microenvironment. In this review, the features of porous materials and the implications of porosity in the context of medical devices is discussed. Common methods to create porous materials are also discussed, as well as the parameters that are used to tune pore features. Responses toward porous biomaterials are also reviewed, including the various stages of the FBR, hemocompatibility, biofilm formation, and calcification. Finally, these host responses are considered in tissue specific locations including the subcutis, bone, cardiovascular system, brain, eye, and female reproductive tract. The effects of porosity across the various tissues of the body is highlighted and the need to consider the tissue context when engineering biomaterials is emphasized.
Collapse
Affiliation(s)
- Jamie L Hernandez
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| | - Kim A Woodrow
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Seattle, WA, 98195, USA
| |
Collapse
|
13
|
A new way to evaluate thrombotic risk in failure heart and ventricular assist devices. MEDICINE IN NOVEL TECHNOLOGY AND DEVICES 2022. [DOI: 10.1016/j.medntd.2022.100135] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
14
|
Blum C, Groß-Hardt S, Steinseifer U, Neidlin M. An Accelerated Thrombosis Model for Computational Fluid Dynamics Simulations in Rotary Blood Pumps. Cardiovasc Eng Technol 2022; 13:638-649. [PMID: 35031981 PMCID: PMC9499893 DOI: 10.1007/s13239-021-00606-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/14/2021] [Indexed: 11/30/2022]
Abstract
Purpose Thrombosis ranks among the major complications in blood-carrying medical devices and a better understanding to influence the design related contribution to thrombosis is desirable. Over the past years many computational models of thrombosis have been developed. However, numerically cheap models able to predict localized thrombus risk in complex geometries are still lacking. The aim of the study was to develop and test a computationally efficient model for thrombus risk prediction in rotary blood pumps. Methods We used a two-stage approach to calculate thrombus risk. The first stage involves the computation of velocity and pressure fields by computational fluid dynamic simulations. At the second stage, platelet activation by mechanical and chemical stimuli was determined through species transport with an Eulerian approach. The model was compared with existing clinical data on thrombus deposition within the HeartMate II. Furthermore, an operating point and model parameter sensitivity analysis was performed. Results Our model shows good correlation (R2 > 0.93) with clinical data and identifies the bearing and outlet stator region of the HeartMate II as the location most prone to thrombus formation. The calculation of thrombus risk requires an additional 10–20 core hours of computation time. Conclusion The concentration of activated platelets can be used as a surrogate and computationally low-cost marker to determine potential risk regions of thrombus deposition in a blood pump. Relative comparisons of thrombus risk are possible even considering the intrinsic uncertainty in model parameters and operating conditions. Supplementary Information The online version contains supplementary material available at 10.1007/s13239-021-00606-y.
Collapse
Affiliation(s)
- Christopher Blum
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | | | - Ulrich Steinseifer
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Michael Neidlin
- Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Medical Faculty, RWTH Aachen University, Aachen, Germany.
| |
Collapse
|
15
|
Navarro S, Stegner D, Nieswandt B, Heemskerk JWM, Kuijpers MJE. Temporal Roles of Platelet and Coagulation Pathways in Collagen- and Tissue Factor-Induced Thrombus Formation. Int J Mol Sci 2021; 23:ijms23010358. [PMID: 35008781 PMCID: PMC8745329 DOI: 10.3390/ijms23010358] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 12/31/2022] Open
Abstract
In hemostasis and thrombosis, the complex process of thrombus formation involves different molecular pathways of platelet and coagulation activation. These pathways are considered as operating together at the same time, but this has not been investigated. The objective of our study was to elucidate the time-dependency of key pathways of thrombus and clot formation, initiated by collagen and tissue factor surfaces, where coagulation is triggered via the extrinsic route. Therefore, we adapted a microfluidics whole-blood assay with the Maastricht flow chamber to acutely block molecular pathways by pharmacological intervention at desired time points. Application of the technique revealed crucial roles of glycoprotein VI (GPVI)-induced platelet signaling via Syk kinase as well as factor VIIa-induced thrombin generation, which were confined to the first minutes of thrombus buildup. A novel anti-GPVI Fab EMF-1 was used for this purpose. In addition, platelet activation with the protease-activating receptors 1/4 (PAR1/4) and integrin αIIbβ3 appeared to be prolongedly active and extended to later stages of thrombus and clot formation. This work thereby revealed a more persistent contribution of thrombin receptor-induced platelet activation than of collagen receptor-induced platelet activation to the thrombotic process.
Collapse
Affiliation(s)
- Stefano Navarro
- Institute of Experimental Biomedicine I, University Hospital Würzburg, Würzburg Josef-Schneider-Straße 2, 97080 Wurzburg, Germany; (S.N.); (D.S.); (B.N.)
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, 97080 Wurzburg, Germany
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - David Stegner
- Institute of Experimental Biomedicine I, University Hospital Würzburg, Würzburg Josef-Schneider-Straße 2, 97080 Wurzburg, Germany; (S.N.); (D.S.); (B.N.)
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, 97080 Wurzburg, Germany
| | - Bernhard Nieswandt
- Institute of Experimental Biomedicine I, University Hospital Würzburg, Würzburg Josef-Schneider-Straße 2, 97080 Wurzburg, Germany; (S.N.); (D.S.); (B.N.)
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, 97080 Wurzburg, Germany
| | - Johan W. M. Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Synapse Research Institute, Kon. Emmaplein 7, 6214 KD Maastricht, The Netherlands
- Correspondence: (J.W.M.H.); (M.J.E.K.); Tel.: +31-43-3881674 (M.J.E.K.)
| | - Marijke J. E. Kuijpers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
- Thrombosis Expertise Center, Heart and Vascular Center, Maastricht University Medical Center+, Maastricht, Professor Debyelaan 25, 6229 HX Maastricht, The Netherlands
- Correspondence: (J.W.M.H.); (M.J.E.K.); Tel.: +31-43-3881674 (M.J.E.K.)
| |
Collapse
|
16
|
Ghodrati M, Schlöglhofer T, Maurer A, Khienwad T, Zimpfer D, Beitzke D, Zonta F, Moscato F, Schima H, Aigner P. Effects of the atrium on intraventricular flow patterns during mechanical circulatory support. Int J Artif Organs 2021; 45:421-430. [PMID: 34715752 PMCID: PMC8922056 DOI: 10.1177/03913988211056018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Simulations of the ventricular flow patterns during left ventricular assist device (LVAD) support are mainly performed with idealized cylindrical inflow, neglecting the influence of the atrial vortex. In this study, the influence of the left atrium (LA) on the intra-ventricular flow was investigated via Computational Fluid Dynamics (CFD) simulations. Ventricular flow was simulated by a combined Eulerian (carrier flow)/Lagrangian (particles) approach taking into account either the LA or a cylindrical inflow section to mimic a fully support condition. The flow deviation at the mitral valve, the blood low-velocity volume as well as the residence time and shear stress history of the particles were calculated. Inclusion of the LA deflects the flow at the mitral valve by 25°, resulting in an asymmetric flow jet entering the left ventricle. This reduced the ventricular low-velocity volume by 40% (from 6.4 to 3.9 cm3), increased (40%) the shear stress experienced by particles and correspondingly increased (27%) their residence time. Under the studied conditions, the atrial geometry plays a major role in the development of intraventricular flow patterns. A reliable prediction of blood flow dynamics and consequently thrombosis risk analysis within the ventricle requires the consideration of the LA in computational simulations.
Collapse
Affiliation(s)
- Mojgan Ghodrati
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Thomas Schlöglhofer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria.,Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Alexander Maurer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Thananya Khienwad
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
| | - Daniel Zimpfer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Dietrich Beitzke
- Department of Biomedical Imaging and Image guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Francesco Zonta
- Institute of Fluid Dynamics and Heat Transfer, Technical University of Vienna, Vienna, Austria
| | - Francesco Moscato
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Heinrich Schima
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria.,Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Philipp Aigner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.,Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| |
Collapse
|
17
|
A Continuum Model for the Unfolding of von Willebrand Factor. Ann Biomed Eng 2021; 49:2646-2658. [PMID: 34401970 PMCID: PMC9847011 DOI: 10.1007/s10439-021-02845-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/31/2021] [Indexed: 01/21/2023]
Abstract
von Willebrand Factor is a mechano-sensitive protein circulating in blood that mediates platelet adhesion to subendothelial collagen and platelet aggregation at high shear rates. Its hemostatic function and thrombogenic effect, as well as susceptibility to enzymatic cleavage, are regulated by a conformational change from a collapsed globular state to a stretched state. Therefore, it is essential to account for the conformation of the vWF multimers when modeling vWF-mediated thrombosis or vWF degradation. We introduce a continuum model of vWF unfolding that is developed within the framework of our multi-constituent model of platelet-mediated thrombosis. The model considers two interconvertible vWF species corresponding to the collapsed and stretched conformational states. vWF unfolding takes place via two regimes: tumbling in simple shear and strong unfolding in flows with dominant extensional component. These two regimes were demonstrated in a Couette flow between parallel plates and an extensional flow in a cross-slot geometry. The vWF unfolding model was then verified in several microfluidic systems designed for inducing high-shear vWF-mediated thrombosis and screening for von Willebrand Disease. The model predicted high concentration of stretched vWF in key regions where occlusive thrombosis was observed experimentally. Strong unfolding caused by the extensional flow was limited to the center axis or middle plane of the channels, whereas vWF unfolding near the channel walls relied upon the shear tumbling mechanism. The continuum model of vWF unfolding presented in this work can be employed in numerical simulations of vWF-mediated thrombosis or vWF degradation in complex geometries. However, extending the model to 3-D arbitrary flows and turbulent flows will pose considerable challenges.
Collapse
|
18
|
Wang Y, Luo K, Qiao Y, Fan J. An integrated fluid-chemical model toward modeling the thrombus formation in an idealized model of aortic dissection. Comput Biol Med 2021; 136:104709. [PMID: 34365279 DOI: 10.1016/j.compbiomed.2021.104709] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/05/2021] [Accepted: 07/23/2021] [Indexed: 10/20/2022]
Abstract
Type B aortic dissection is a major aortic catastrophe that can be acutely complicated by rapid expansion, rupture, and malperfusion syndromes. The separation of the intima from aortic walls will form a second blood-filled lumen defined as "false lumen (FL)", where the thrombus is more likely to form due to the local stasis hemodynamic conditions. Complete thrombosis of FL is associated with a beneficial outcome while patency and partial thrombosis will lead to later complications. However, the thrombosis mechanism is still unclear and little is known about the impact of chemical species transported by blood flow on this process. The proteins involved in the coagulation cascade (CC) may play an important role in the process of thrombosis, especially in the activation and stabilization of platelets. Based on this hypothesis, a reduced-order fluid-chemical model was established to simulate CC in an aortic dissection phantom with two tears. A high level of fibrin is continuously observed at the top of the FL and some time-varying areas between two tears, indicating a high likelihood of thrombus formation there. This finding is consistent with the clinical observation. The time evolution of coagulation factors is greatly affected by local hemodynamics, especially in the high disturbance zone where the evolution has characteristics of periodic changes consistent with the flow field. The ability of the proposed model to reproduce the CC response provides a potential application to integrate with a model that can simulate platelet activities, forming a biochemical-based model which would help unveil the mechanisms of thrombosis in FL and the clinical decision of appropriate treatment.
Collapse
Affiliation(s)
- Yan Wang
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| | - Kun Luo
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China.
| | - Yonghui Qiao
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| | - Jianren Fan
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China
| |
Collapse
|
19
|
Jia D, Peroni M, Khalapyan T, Esmaily M. An Efficient Assisted Bidirectional Glenn Design With Lowered Superior Vena Cava Pressure for Stage-One Single Ventricle Patients. J Biomech Eng 2021; 143:1098851. [PMID: 33590839 DOI: 10.1115/1.4050170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Indexed: 11/08/2022]
Abstract
Recently, the assisted bidirectional Glenn (ABG) procedure has been proposed as an alternative to the modified Blalock-Taussig shunt (mBTS) operation for neonates with single-ventricle physiology. Despite success in reducing heart workload and maintaining sufficient pulmonary flow, the ABG also raised the superior vena cava (SVC) pressure to a level that may not be tolerated by infants. To lower the SVC pressure, we propose a modified version of the ABG (mABG), in which a shunt with a slit-shaped nozzle exit is inserted at the junction of the right and left brachiocephalic veins. The proposed operation is compared against the ABG, the mBTS, and the bidirectional Glenn (BDG) operations using closed-loop multiscale simulations. Both normal (2.3 Wood units-m2) and high (7 Wood units-m2) pulmonary vascular resistance (PVR) values are simulated. The mABG provides the highest oxygen saturation, oxygen delivery, and pulmonary flow rate in comparison to the BDG and the ABG. At normal PVR, the SVC pressure is significantly reduced below that of the ABG and the BDG (mABG: 4; ABG: 8; BDG: 6; mBTS: 3 mmHg). However, the SVC pressure remains high at high PVR (mABG: 15; ABG: 16; BDG: 12; mBTS: 3 mmHg), motivating an optimization study to improve the ABG hemodynamics efficiency for a broader range of conditions in the future. Overall, the mABG preserves all advantages of the original ABG procedure while reducing the SVC pressure at normal PVR.
Collapse
Affiliation(s)
- Dongjie Jia
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850
| | - Matthew Peroni
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850
| | | | - Mahdi Esmaily
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850
| |
Collapse
|
20
|
Zhussupbekov M, Wu WT, Jamiolkowski MA, Massoudi M, Antaki JF. Influence of shear rate and surface chemistry on thrombus formation in micro-crevice. J Biomech 2021; 121:110397. [PMID: 33845357 DOI: 10.1016/j.jbiomech.2021.110397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 03/03/2021] [Indexed: 02/02/2023]
Abstract
Thromboembolic complications remain a central issue in management of patients on mechanical circulatory support. Despite the best practices employed in design and manufacturing of modern ventricular assist devices, complexity and modular nature of these systems often introduces internal steps and crevices in the flow path which can serve as nidus for thrombus formation. Thrombotic potential is influenced by multiple factors including the characteristics of the flow and surface chemistry of the biomaterial. This study explored these elements in the setting of blood flow over a micro-crevice using a multi-constituent numerical model of thrombosis. The simulations reproduced the platelet deposition patterns observed experimentally and elucidated the role of flow, shear rate, and surface chemistry in shaping the deposition. The results offer insights for design and operation of blood-contacting devices.
Collapse
Affiliation(s)
- Mansur Zhussupbekov
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Wei-Tao Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China
| | - Megan A Jamiolkowski
- U.S. Food and Drug Administration (FDA), Center for Devices and Radiological Health (CDRH), Office of Science and Engineering Laboratories (OSEL), Silver Spring, Maryland, USA
| | - Mehrdad Massoudi
- U.S. Department of Energy, National Energy Technology Laboratory (NETL), Pittsburgh, PA, USA
| | - James F Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA.
| |
Collapse
|
21
|
Dai WF, Wu P, Liu GM. A two-phase flow approach for modeling blood stasis and estimating the thrombosis potential of a ventricular assist device. Int J Artif Organs 2020; 44:471-480. [PMID: 33258722 DOI: 10.1177/0391398820975405] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Thrombosis and its related events have become a major concern during the development and optimization of ventricular assist devices (VADs, also called blood pumps), and limit their clinical use and economic benefits. Attempts have been made to model the thrombosis formation, considering hemodynamic and biochemical processes. However, the complexities and computational expenses are prohibitive. Blood stasis is one of the key factors which may lead to the formation of thrombosis and excessive thromboembolic risks for patients. This study proposed a novel approach for modeling blood stasis, based on a two-phase flow principle. The locations of blood residual can be tracked over time, so that regions of blood stasis can be identified. The blood stasis in an axial blood pump is simulated under various working conditions, the results agree well with the experimental results. In contrast, conventional hemodynamic metrics such as velocity, time-averaged wall shear stress (TAWSS), and relative residence time (RRT), were contradictory in judging risk of blood stasis and thrombosis, and inconsistent with experimental results. We also found that the pump operating at the designed rotational speed is less prone to blood stasis. The model provides an efficient and fast alternative for evaluating blood stasis and thrombosis potential in blood pumps, and will be a valuable addition to the tools to support the design and improvement of VADs.
Collapse
Affiliation(s)
- Wei-Feng Dai
- Artificial Organ Laboratory, Bio-Manufacturing Research Centre, School of Mechanical and Electric Engineering, Soochow University, Suzhou, Jiangsu, China
| | - Peng Wu
- Artificial Organ Laboratory, Bio-Manufacturing Research Centre, School of Mechanical and Electric Engineering, Soochow University, Suzhou, Jiangsu, China
| | - Guang-Mao Liu
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| |
Collapse
|
22
|
Wu WT, Aubry N, Antaki JF, Massoudi M. Simulation of blood flow in a sudden expansion channel and a coronary artery. JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS 2020; 376:112856. [PMID: 34703076 PMCID: PMC8545272 DOI: 10.1016/j.cam.2020.112856] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In this paper, we numerically simulate the flow of blood in two benchmark problems: the flow in a sudden expansion channel and the flow through an idealized curved coronary artery with pulsatile inlet velocity. Blood is modeled as a suspension (a non-linear complex fluid) and the movement of the red blood cell (RBCs) is modeled by using a concentration flux equation. The viscosity of blood is obtained from experimental data. In the sudden expansion flow, the predicted velocity profiles for two different Reynolds numbers (based on the inlet velocity) agree well with the available experiments; furthermore, the numerical results also show that after the sudden expansion there exists a RBCs depletion region. For the second problem, the idealized curved coronary artery, it is found that the RBCs move towards and concentrate near the inner surface where the viscosity is higher and the shear stress lower; this phenomenon may be related to the atherosclerotic plaque formation which usually occurs on the inside surface of the arteries.
Collapse
Affiliation(s)
- Wei-Tao Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, J.S., 210094, China
| | - Nadine Aubry
- Department of Mechanical Engineering, Tufts University, Medford, MA, 02155, USA
| | - James F. Antaki
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Mehrdad Massoudi
- U. S. Department of Energy, National Energy Technology Laboratory (NETL), Pittsburgh, PA, 15236, USA
| |
Collapse
|
23
|
Yang L, Neuberger T, Manning KB. In vitro real-time magnetic resonance imaging for quantification of thrombosis. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2020; 34:285-295. [PMID: 32729094 DOI: 10.1007/s10334-020-00872-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 01/28/2023]
Abstract
OBJECTIVES Thrombosis is a leading cause of failure for cardiovascular devices. While computational simulations are a powerful tool to predict thrombosis and evaluate the risk for medical devices, limited experimental data are available to validate the simulations. The aim of the current study is to provide experimental data of a growing thrombus for device-induced thrombosis. MATERIALS AND METHODS Thrombosis within a backward-facing step (BFS), or sudden expansion was investigated, using bovine and human blood circulated through the BFS model for 30 min, with a constant inflow rate of 0.76 L/min. Real-time three-dimensional flow-compensated magnetic resonance imaging (MRI), supported with Magnevist, a contrast agent improving thrombus delineation, was applied to quantify thrombus deposition and growth within the model. RESULTS The study showed that the BFS model induced a flow recirculation region, which facilitated thrombosis. By 30 min, in comparison to bovine blood, human blood resulted in smaller thrombus formation, in terms of the length (13.3 ± 0.6 vs. 18.1 ± 1.3 mm), height (2.3 ± 0.1 vs. 2.6 ± 0.04 mm), surface area exposed to blood (0.67 ± 0.03 vs 1.05 ± 0.08 cm2), and volume (0.069 ± 0.004 vs. 0.093 ± 0.007 cm3), with p < 0.01. Normalization of the thrombus measurements, which excluded the flow recirculation effects, suggested that the thrombus sizes increased during the first 15 min and stabilized after 20 min. Blood properties, including viscosity, hematocrit, and platelet count affected thrombosis. CONCLUSION For the first time, contrast agent-supported real-time MRI was performed to investigate thrombus deposition and growth within a sudden expansion. This study provides experimental data for device-induced thrombosis, which is valuable for validation of computational thrombosis simulations.
Collapse
Affiliation(s)
- Ling Yang
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA
| | - Thomas Neuberger
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA.,Huck Institutes of Life Science, The Pennsylvania State University, University Park, PA, USA
| | - Keefe B Manning
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA, USA. .,Department of Surgery, Penn State Hershey Medical Center, Hershey, PA, USA.
| |
Collapse
|
24
|
Bouchnita A, Terekhov K, Nony P, Vassilevski Y, Volpert V. A mathematical model to quantify the effects of platelet count, shear rate, and injury size on the initiation of blood coagulation under venous flow conditions. PLoS One 2020; 15:e0235392. [PMID: 32726315 PMCID: PMC7390270 DOI: 10.1371/journal.pone.0235392] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 06/16/2020] [Indexed: 11/18/2022] Open
Abstract
Platelets upregulate the generation of thrombin and reinforce the fibrin clot which increases the incidence risk of venous thromboembolism (VTE). However, the role of platelets in the pathogenesis of venous cardiovascular diseases remains hard to quantify. An experimentally validated model of thrombin generation dynamics is formulated. The model predicts that a high platelet count increases the peak value of generated thrombin as well as the endogenous thrombin potential (ETP) as reported in experimental data. To investigate the effects of platelets density, shear rate, and wound size on the initiation of blood coagulation, we calibrate a previously developed model of venous thrombus formation and implement it in 3D using a novel cell-centered finite-volume solver. We conduct numerical simulations to reproduce in vitro experiments of blood coagulation in microfluidic capillaries. Then, we derive a reduced one-equation model of thrombin distribution from the previous model under simplifying hypotheses and we use it to determine the conditions of clotting initiation on the platelet count, the shear rate, and the plasma composition. The initiation of clotting also exhibits a threshold response to the size of the wounded region in good agreement with the reported experimental findings.
Collapse
Affiliation(s)
| | - Kirill Terekhov
- Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
| | - Patrice Nony
- Services de Pharmacologie Clinique, Hospices Civils de Lyon, Lyon, France
| | - Yuri Vassilevski
- Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
- Sechenov University, Moscow, Russia
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Vitaly Volpert
- Marchuk Institute of Numerical Mathematics, Russian Academy of Sciences, Moscow, Russia
- Institut Camille Jordan, Université Lyon 1, Villeurbanne, France
- INRIA team Dracula, INRIA Lyon La Doua, Villeurbanne, France
- Peoples’ Friendship University of Russia (RUDN University), Moscow, Russia
| |
Collapse
|
25
|
Wu WT, Zhussupbekov M, Aubry N, Antaki JF, Massoudi M. Simulation of thrombosis in a stenotic microchannel: The effects of vWF-enhanced shear activation of platelets. INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE 2020; 147:103206. [PMID: 34565829 PMCID: PMC8462794 DOI: 10.1016/j.ijengsci.2019.103206] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This study was undertaken to develop a numerical/computational simulation of von Willebrand Factor (vWF) - mediated platelet shear activation and deposition in an idealized stenosis. Blood is treated as a multi-constituent mixture comprised of a linear fluid component and a porous solid component (thrombus). Chemical and biological species involved in coagulation are modeled using a system of coupled convection-reaction-diffusion (CRD) equations. This study considers the cumulative effect of shear stress (history) on platelet activation. The vWF activity is modeled as an enhancement function for the shear stress accumulation and is related to the experimentally-observed unfolding rate of vWF. A series of simulations were performed in an idealized stenosis in which the predicted platelets deposition agreed well with previous experimental observations spatially and temporally, including the reduction of platelet deposition with decreasing expansion angle. Further simulation indicated a direct relationship between vWF-mediated platelet deposition and degree of stenosis. Based on the success with these benchmark simulations, it is hoped that the model presented here may provide additional insight into vWF-mediated thrombosis and prove useful for the development of more hemo-compatible blood-wetted devices in the future.
Collapse
Affiliation(s)
- Wei-Tao Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, J.S., 210094, China
| | - Mansur Zhussupbekov
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Nadine Aubry
- Department of Mechanical Engineering, Northeastern University, Boston, MA, 02115, USA
| | - James F Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Mehrdad Massoudi
- U. S. Department of Energy, National Energy Technology Laboratory (NETL), Pittsburgh, PA, 15236, USA
| |
Collapse
|
26
|
Sefton MV, Gorbet MB. Nonthrombogenic Treatments and Strategies. Biomater Sci 2020. [DOI: 10.1016/b978-0-12-816137-1.00035-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
27
|
Liu GM, Zhang Y, Chen HB, Hou JF, Jin DH, Gui XM, Hu SS. Platelet deposition estimation: A novel method for emulating the pump thrombosis potential of blood pumps. Artif Organs 2019; 44:465-472. [PMID: 31853998 DOI: 10.1111/aor.13620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/02/2019] [Accepted: 12/12/2019] [Indexed: 01/19/2023]
Abstract
Pump thrombosis potential exists in most blood pumps and limits their clinical use. To improve the pump thrombosis performance of blood pumps, a method for emulating the platelet deposition on the flow passage component surfaces inside blood pumps was presented and tested. The method emulates the blood platelet deposition, employing laser-induced fluorescence tracing technology. The blood pump was rotated in a mock circulation loop with deionized water filled with fluorescent particles. The component surfaces were then explored via laser. The fluorescent particles were induced by laser and imaged in a charge-coupled device (CCD) camera to show the distribution of fluorescent particles gathering on the blood pump component surfaces. The activated platelet deposition was emulated by fluorescent particle gathering. The experiment showed obvious particle gathering on the interface surfaces and cross-sectional surface (perpendicular to the flow). This platelet deposition estimation (PDE) method can be easily incorporated in the in vitro testing phase to analyze and decrease a pump's thrombosis potential before animal experimentation, thereby reducing the cost of blood pump development. This methodology of emulating blood platelet deposition indicates its potential for improving flow passage component structure and reducing device thrombosis of blood pumps.
Collapse
Affiliation(s)
- Guang-Mao Liu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yan Zhang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hai-Bo Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jian-Feng Hou
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Dong-Hai Jin
- School of Energy and Power Engineering, Beihang University, Beijing, China
| | - Xing-Min Gui
- School of Energy and Power Engineering, Beihang University, Beijing, China
| | - Sheng-Shou Hu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| |
Collapse
|
28
|
Liu GM, Chen HB, Hou JF, Zhang Y, Hu SS. Platelet adhesion emulation: A novel method for estimating the device thrombosis potential of a ventricular assist device. Int J Artif Organs 2019; 43:252-257. [PMID: 31709882 DOI: 10.1177/0391398819885946] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Device thrombosis inside ventricular assist devices remains a limitation to their long-term clinical use. Thrombosis potential exists in almost all ventricular assist devices because the device-induced high shear stress and vortices can activate platelets, which then aggregate and adhere to the surfaces inside the ventricular assist device. To decrease the device thrombosis potential of long-term use of ventricular assist devices, a methodology entitled platelet adhesion emulation for predicting the thrombosis potential and thrombosis position inside the ventricular assist devices is developed. The platelet adhesion emulation methodology combines numerical simulations with in vitro experiments by correlating the structure of the flow passage components within the ventricular assist device with the platelet adhesion to estimate the thrombosis potential and location, with the goal of developing ventricular assist devices with optimized antithrombotic performance. Platelet adhesion emulation is aimed at decreasing the device thrombus potential of ventricular assist devices. The platelet adhesion emulation effectiveness is validated by simulating and testing an axial left ventricular assist device. The blood velocity relative to the surfaces of the flow passage components is calculated to estimate the platelet adhesion potential, indicating the probability of thrombus formation on the surfaces. Platelet adhesion emulation experiments conducted in a mock circulation loop with pump prototypes show the distribution of platelet adhesion on the surfaces. This methodology of emulating the device thrombosis distribution indicates the potential for improving the component structure and reducing the device thrombosis of ventricular assist devices.
Collapse
Affiliation(s)
- Guang-Mao Liu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hai-bo Chen
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jian-feng Hou
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yan Zhang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Sheng-shou Hu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| |
Collapse
|
29
|
Yesudasan S, Averett RD. Recent advances in computational modeling of fibrin clot formation: A review. Comput Biol Chem 2019; 83:107148. [PMID: 31751883 DOI: 10.1016/j.compbiolchem.2019.107148] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 09/17/2019] [Accepted: 10/15/2019] [Indexed: 12/12/2022]
Abstract
The field of thrombosis and hemostasis is crucial for understanding and developing new therapies for pathologies such as deep vein thrombosis, diabetes related strokes, pulmonary embolisms, and hemorrhaging related diseases. In the last two decades, an exponential growth in studies related to fibrin clot formation using computational tools has been observed. Despite this growth, the complete mechanism behind thrombus formation and hemostasis has been long and rife with obstacles; however, significant progress has been made in the present century. The computational models and methods used in this context are diversified into different spatiotemporal scales, yet there is no single model which can predict both physiological and mechanical properties of fibrin clots. In this review, we list the major strategies employed by researchers in modeling fibrin clot formation using recent and existing computational techniques. This review organizes the computational strategies into continuum level, system level, discrete particle (DPD), and multi-scale methods. We also discuss strengths and weaknesses of various methods and future directions in which computational modeling of fibrin clots can advance.
Collapse
Affiliation(s)
- Sumith Yesudasan
- School of Chemical, Materials and Biomedical Engineering, University of Georgia, 597 D.W. Brooks Drive, Athens, GA 30602
| | - Rodney D Averett
- School of Chemical, Materials and Biomedical Engineering, University of Georgia, 597 D.W. Brooks Drive, Athens, GA 30602.
| |
Collapse
|
30
|
Kushchenko YK, Belyaev AV. Effects of hydrophobicity, tethering and size on flow-induced activation of von Willebrand factor multimers. J Theor Biol 2019; 485:110050. [PMID: 31618612 DOI: 10.1016/j.jtbi.2019.110050] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 09/12/2019] [Accepted: 10/12/2019] [Indexed: 01/14/2023]
Abstract
Von Willebrand factor (VWF) is a multimeric protein of blood plasma that mediates platelet adhesion to injury under strong hemodynamic flows in arterias and microvasvulature. We present a 3D coarse-grained computer model of VWF multimers in flowing viscous fluid that explicitely grasps the dynamics, the conformational changes and the hydrodynamics-induced activation of adhesivity of these protein concatamers to GPIb receptor of blood platelets. The model is based on the fluctuating Lattice Boltzmann method for modelling the hydrodynamics in the simulation box and the Lagrangian particle dynamics coupled to the fluid by a viscous drag force. The model has been validated by the comparison with the experimental data found in literature. We studied the effect of hydrophobic interactions on the conformational dynamics of VWF multimers. The simulations suggest that the contour length is an important parameter that controls the functionality of VWF multimers in blood. We also demonstrate that tethering to the surface of a vessel wall promoted the flow-induced activation of VWF, while those multimers that remain untethered and move freely in the blood plasma require a stronger shearing to get activated.
Collapse
Affiliation(s)
- Yulia K Kushchenko
- Lomonosov Moscow State University, Faculty of Physics, Moscow 119991, Russia
| | - Aleksey V Belyaev
- Lomonosov Moscow State University, Faculty of Physics, Moscow 119991, Russia; S.M. Nikol'skii Mathematical Institute, RUDN University, Moscow 115419, Russia.
| |
Collapse
|
31
|
Thrombus growth modelling and stenosis prediction in the cerebral microvasculature. J Theor Biol 2019; 478:1-13. [PMID: 31207204 DOI: 10.1016/j.jtbi.2019.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 06/08/2019] [Accepted: 06/12/2019] [Indexed: 11/22/2022]
Abstract
Cerebral microvascular occlusions cause restriction of blood supply to the brain, thus potentially severely impacting cognitive abilities. Thus, accurate prediction of thrombus growth in realistic geometries is important. Thrombi growth in an existing 13-generation cerebral microvasculature network is simulated here to study the haemodynamic effects of single and multiple blockages on the occlusion of the network. Compared to a single vessel, in a network, the occlusion probability is found to be different. It is the downstream/smaller arterioles (i.e. the 3rd, 4th, 5th, 6th generation arterioles in this study) that tend to reach occlusion first in a network and thus are the critical vessels. Simulations of simultaneous growth of two independent thrombi in the network (referred to here as the two-block case) show a close coupling between the locations of the various blocks in the network, each influencing the other's growth. The presence of the lead block (LB) slows the growth of the trailing block (TB). In some cases, it stops the TB's growth thereby preventing it from occluding the vessel. Findings in this work thus indicate that, to prevent ischaemia, blocks in the smaller arterioles need to be identified and treated first, and that this is more critical if the number of simultaneous blocks is higher.
Collapse
|
32
|
Khodaee F, Barakat M, Abbasi M, Dvir D, Azadani AN. Incomplete expansion of transcatheter aortic valves is associated with propensity for valve thrombosis. Interact Cardiovasc Thorac Surg 2019; 30:39-46. [DOI: 10.1093/icvts/ivz213] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/24/2019] [Accepted: 08/04/2019] [Indexed: 11/14/2022] Open
Abstract
Abstract
OBJECTIVES
Clinical and subclinical leaflet thromboses are increasingly recognized complications following transcatheter aortic valve replacement. Identification of the risk factors is important to mitigate the occurrence of leaflet thrombosis in transcatheter aortic valves (TAVs) and ensure their long-term function. The goal of this study was to determine the effect of incomplete expansion of TAVs on the likelihood of leaflet thrombosis following transcatheter aortic valve replacement.
METHODS
Using experimental and computational methods, 3-dimensional unsteady flow fields of 26-mm SAPIEN 3 valves expanded to 3 different diameters (i.e. 26.0 mm, 23.4 mm and 20.8 mm) were determined in patient-specific geometries. The diameters corresponded to 100%, 90% and 80% stent expansion, respectively. To address the potential difference in the likelihood of leaflet thrombosis, blood residence time (i.e. stasis) and viscous shear stress on the surface of TAV leaflets were quantified and compared.
RESULTS
The results indicated that TAV underexpansion increased blood stasis on the TAV leaflets. Blood residence time on the surface of the leaflets after 80% and 90% TAV expansion on average was 9.4% and 4.1% more than that of the fully expanded TAV, respectively. In addition, areas of blood stasis time of more than 0.5 s, which are highly prone to platelet activation, increased linearly as the degree of TAV underexpansion increased.
CONCLUSIONS
Incomplete expansion of TAVs increases blood stasis on the surface of TAV leaflets. Regions of blood stasis promote platelet activation and thrombotic events. TAV underexpansion can therefore increase the risk of leaflet thrombosis in patients with transcatheter aortic valve replacement.
Collapse
Affiliation(s)
- Farhan Khodaee
- The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials Engineering, University of Denver, Denver, CO, USA
| | - Mohammed Barakat
- The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials Engineering, University of Denver, Denver, CO, USA
| | - Mostafa Abbasi
- The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials Engineering, University of Denver, Denver, CO, USA
| | - Danny Dvir
- Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Ali N Azadani
- The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials Engineering, University of Denver, Denver, CO, USA
| |
Collapse
|
33
|
Khodaee F, Qiu D, Dvir D, Azadani AN. Reducing the risk of leaflet thrombosis in transcatheter aortic valve-in-valve implantation by BASILICA: a computational simulation study. EUROINTERVENTION 2019; 15:67-70. [PMID: 30888960 DOI: 10.4244/eij-d-19-00048] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Farhan Khodaee
- The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials Engineering, University of Denver, Denver, CO, USA
| | | | | | | |
Collapse
|
34
|
Wu WT, Aubry N, Antaki JF, Massoudi M. A non-linear fluid suspension model for blood flow. INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS 2019; 109:32-39. [PMID: 31447489 PMCID: PMC6707772 DOI: 10.1016/j.ijnonlinmec.2018.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Motivated by the complex rheological behaviors observed in small/micro scale blood vessels, such as the Fahraeus effect, plasma-skimming, shear-thinning, etc., we develop a non-linear suspension model for blood. The viscosity is assumed to depend on the volume fraction (hematocrit) and the shear rate. The migration of the red blood cells (RBCs) is studied using a concentration flux equation. A parametric study with two representative problems, namely simple shear flow and a pressure driven flow demonstrate the ability of this reduced-order model to reproduce several key features of the two-fluid model (mixture theory approach), with much lower computational cost.
Collapse
Affiliation(s)
- Wei-Tao Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, J.S., 210094, China
| | - Nadine Aubry
- Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115, USA
| | - James F. Antaki
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Mehrdad Massoudi
- U. S. Department of Energy, National Energy Technology Laboratory (NETL), Pittsburgh, PA, 15236, USA
| |
Collapse
|
35
|
Kadri OE, Chandran VD, Surblyte M, Voronov RS. In vivo measurement of blood clot mechanics from computational fluid dynamics based on intravital microscopy images. Comput Biol Med 2019; 106:1-11. [PMID: 30660757 PMCID: PMC6390965 DOI: 10.1016/j.compbiomed.2019.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 12/31/2022]
Abstract
Ischemia which leads to heart attacks and strokes is one of the major causes of death in the world. Whether an occlusion occurs or not depends on the ability of a growing thrombus to resist flow forces exerted on its structure. This manuscript provides the first known in vivo measurement of how much stress a clot can withstand, before yielding to the surrounding blood flow. Namely, Lattice-Boltzmann Method flow simulations are performed based on 3D clot geometries, which are estimated from intravital microscopy images of laser-induced injuries in cremaster microvasculature of live mice. In addition to reporting the blood clot yield stresses, we also show that the thrombus "core" does not experience significant deformation, while its "shell" does. This indicates that the shell is more prone to embolization. Therefore, drugs should be designed to target the shell selectively, while leaving the core intact to minimize excessive bleeding. Finally, we laid down a foundation for a nondimensionalization procedure which unraveled a relationship between clot mechanics and biology. Hence, the proposed framework could ultimately lead to a unified theory of thrombogenesis, capable of explaining all clotting events. Thus, the findings presented herein will be beneficial to the understanding and treatment of heart attacks, strokes and hemophilia.
Collapse
Affiliation(s)
- Olufemi Emmanuel Kadri
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Vishnu Deep Chandran
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Migle Surblyte
- Ying Wu College of Computing Sciences, Department of Computer Science, New Jersey Institute of Technology, Newark, NJ, 07102, USA
| | - Roman S Voronov
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA.
| |
Collapse
|
36
|
Cleary SJ, Page CP. Gustav Born: pioneer in imaging platelet and leukocyte biology. Platelets 2018; 29:766-770. [PMID: 30411649 DOI: 10.1080/09537104.2018.1535001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Gustav Born achieved scientific fame for his application of light transmission aggregometry to the study of platelet function, but also led interdisciplinary research teams in pioneering quantitative in vivo imaging studies of platelet aggregation and leukocyte adhesion, and in conducting the first research into the biomechanical factors underlying atherosclerotic plaque rupture. Gus Born also communicated both current research findings and an integrated understanding of cardiovascular biology to a wide audience through acting as scientific advisor on several television productions. Using footage from two of these films, we discuss Gustav Born's scientific achievements and legacy.
Collapse
Affiliation(s)
- Simon J Cleary
- a Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science , King's College London , London , UK.,b Department of Medicine , University of California San Francisco , San Francisco , CA , USA
| | - Clive P Page
- a Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science , King's College London , London , UK
| |
Collapse
|
37
|
Horn JD, Maitland DJ, Hartman J, Ortega JM. A computational thrombus formation model: application to an idealized two-dimensional aneurysm treated with bare metal coils. Biomech Model Mechanobiol 2018; 17:1821-1838. [DOI: 10.1007/s10237-018-1059-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 07/21/2018] [Indexed: 10/28/2022]
|
38
|
Hosseinzadegan H, Tafti DK. A Predictive Model of Thrombus Growth in Stenosed Vessels with Dynamic Geometries. J Med Biol Eng 2018. [DOI: 10.1007/s40846-018-0443-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
39
|
Computational Fluid Dynamics Assessment Associated with Transcatheter Heart Valve Prostheses: A Position Paper of the ISO Working Group. Cardiovasc Eng Technol 2018; 9:289-299. [PMID: 29675697 DOI: 10.1007/s13239-018-0349-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 03/08/2018] [Indexed: 12/19/2022]
Abstract
The governing international standard for the development of prosthetic heart valves is International Organization for Standardization (ISO) 5840. This standard requires the assessment of the thrombus potential of transcatheter heart valve substitutes using an integrated thrombus evaluation. Besides experimental flow field assessment and ex vivo flow testing, computational fluid dynamics is a critical component of this integrated approach. This position paper is intended to provide and discuss best practices for the setup of a computational model, numerical solving, post-processing, data evaluation and reporting, as it relates to transcatheter heart valve substitutes. This paper is not intended to be a review of current computational technology; instead, it represents the position of the ISO working group consisting of experts from academia and industry with regards to considerations for computational fluid dynamic assessment of transcatheter heart valve substitutes.
Collapse
|
40
|
A Short Review of Advances in the Modelling of Blood Rheology and Clot Formation. FLUIDS 2017. [DOI: 10.3390/fluids2030035] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
41
|
Numerical Simulation of Red Blood Cell-Induced Platelet Transport in Saccular Aneurysms. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7050484] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
42
|
Wu WT, Yang F, Wu J, Aubry N, Massoudi M, Antaki JF. High fidelity computational simulation of thrombus formation in Thoratec HeartMate II continuous flow ventricular assist device. Sci Rep 2016; 6:38025. [PMID: 27905492 PMCID: PMC5131309 DOI: 10.1038/srep38025] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 11/04/2016] [Indexed: 12/22/2022] Open
Abstract
Continuous flow ventricular assist devices (cfVADs) provide a life-saving therapy for severe heart failure. However, in recent years, the incidence of device-related thrombosis (resulting in stroke, device-exchange surgery or premature death) has been increasing dramatically, which has alarmed both the medical community and the FDA. The objective of this study was to gain improved understanding of the initiation and progression of thrombosis in one of the most commonly used cfVADs, the Thoratec HeartMate II. A computational fluid dynamics simulation (CFD) was performed using our recently updated mathematical model of thrombosis. The patterns of deposition predicted by simulation agreed well with clinical observations. Furthermore, thrombus accumulation was found to increase with decreased flow rate, and can be completely suppressed by the application of anticoagulants and/or improvement of surface chemistry. To our knowledge, this is the first simulation to explicitly model the processes of platelet deposition and thrombus growth in a continuous flow blood pump and thereby replicate patterns of deposition observed clinically. The use of this simulation tool over a range of hemodynamic, hematological, and anticoagulation conditions could assist physicians to personalize clinical management to mitigate the risk of thrombosis. It may also contribute to the design of future VADs that are less thrombogenic.
Collapse
Affiliation(s)
- Wei-Tao Wu
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Fang Yang
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun 130012, China
| | - Jingchun Wu
- Advanced Design Optimization, Irvine, CA, 92618, USA
| | - Nadine Aubry
- Department of Mechanical Engineering, Northeastern University, Boston, MA, 02115, USA
| | - Mehrdad Massoudi
- U. S. Department of Energy, National Energy Technology Laboratory (NETL), PA, 15236, USA
| | - James F. Antaki
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| |
Collapse
|