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Li Y, Li Y, Chen H. The effect of ultrasound-assisted thrombolysis studied in blood-on-a-chip. Artif Organs 2024; 48:734-742. [PMID: 38380722 DOI: 10.1111/aor.14731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/24/2024] [Accepted: 02/07/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND Thromboembolism, which leads to pulmonary embolism and ischemic stroke, remains one of the main causes of death. Ultrasound-assisted thrombolysis (UAT) is an effective thrombolytic method. However, further studies are required to elucidate the mechanism of ultrasound on arterial and venous thrombi. METHODS We employed the blood-on-a-chip technology to simulate thrombus formation in coronary stenosis and deep vein valves. Subsequently, UAT was conducted on the chip to assess the impact of ultrasound on thrombolysis under varying flow conditions. Real-time fluorescence was used to assess thrombolysis and drug penetration. Finally, scanning electron microscopy and immunofluorescence were used to determine the effect of ultrasound on fibrinolysis. RESULTS The study revealed that UAT enhanced the thrombolytic rate by 40% in the coronary stenosis chip and by 10% in the deep venous valves chip. This enhancement is attributed to the disruption of crosslinked fibrin fibers by ultrasound, leading to increased urokinase diffusion within the thrombus and accumulation of plasminogen on the fibrinogen α chain. Moreover, the acceleration of the dissolution rate of thrombi in the venous valve chip by ultrasound was not as significant as that in the coronary stenosis chip. CONCLUSION These findings highlight the differential impact of ultrasound on thrombolysis under various flow conditions and emphasize the valuable role of the blood-on-a-chip technology in exploring thrombolysis mechanisms.
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Affiliation(s)
- Yan Li
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing, China
| | - Yongjian Li
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing, China
| | - Haosheng Chen
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing, China
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2
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Othman HY, Zaki IAH, Isa MR, Ming LC, Zulkifly HH. A systematic review of thromboembolic complications and outcomes in hospitalised COVID-19 patients. BMC Infect Dis 2024; 24:484. [PMID: 38730292 PMCID: PMC11088167 DOI: 10.1186/s12879-024-09374-1] [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: 11/14/2023] [Accepted: 05/03/2024] [Indexed: 05/12/2024] Open
Abstract
Thromboembolic (TE) complications [myocardial infarction (MI), stroke, deep vein thrombosis (DVT), and pulmonary embolism (PE)] are common causes of mortality in hospitalised COVID-19 patients. Therefore, this review was undertaken to explore the incidence of TE complications and mortality associated with TE complications in hospitalised COVID-19 patients from different studies. A literature search was performed using ScienceDirect and PubMed databases using the MeSH term search strategy of "COVID-19", "thromboembolic complication", "venous thromboembolism", "arterial thromboembolism", "deep vein thrombosis", "pulmonary embolism", "myocardial infarction", "stroke", and "mortality". There were 33 studies included in this review. Studies have revealed that COVID-19 patients tend to develop venous thromboembolism (PE:1.0-40.0% and DVT:0.4-84%) compared to arterial thromboembolism (stroke:0.5-15.2% and MI:0.8-8.7%). Lastly, the all-cause mortality of COVID-19 patients ranged from 4.8 to 63%, whereas the incidence of mortality associated with TE complications was between 5% and 48%. A wide range of incidences of TE complications and mortality associated with TE complications can be seen among hospitalized COVID-19 patients. Therefore, every patient should be assessed for the risk of thromboembolic complications and provided with an appropriate thromboprophylaxis management plan tailored to their individual needs.
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Affiliation(s)
- Hanies Yuhana Othman
- Department of Clinical Pharmacy, Fakulti Farmasi, Universiti Teknologi MARA Cawangan Selangor, Kampus Puncak Alam, Bandar Puncak Alam, Selangor, Malaysia
| | - Izzati Abdul Halim Zaki
- Department of Clinical Pharmacy, Fakulti Farmasi, Universiti Teknologi MARA Cawangan Selangor, Kampus Puncak Alam, Bandar Puncak Alam, Selangor, Malaysia
- Cardiology Therapeutics Research Group, Universiti Teknologi MARA, Puncak Alam, Selangor, Malaysia
| | - Mohamad Rodi Isa
- Faculty of Medicine, Universiti Teknologi MARA Selangor, Sungai Buloh Campus, Sungai Buloh, Selangor, Malaysia
| | - Long Chiau Ming
- School of Medical and Life Sciences, Sunway University, Sunway City, Selangor, Malaysia
| | - Hanis Hanum Zulkifly
- Department of Clinical Pharmacy, Fakulti Farmasi, Universiti Teknologi MARA Cawangan Selangor, Kampus Puncak Alam, Bandar Puncak Alam, Selangor, Malaysia.
- Cardiology Therapeutics Research Group, Universiti Teknologi MARA, Puncak Alam, Selangor, Malaysia.
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Dai H, Chai S, Yao Y, Tang W, Shi J, Jiang Q, Zhu L. Effect of intermittent pneumatic compression on preventing deep vein thrombosis using microfluidic vein chip. Front Bioeng Biotechnol 2023; 11:1281503. [PMID: 38026856 PMCID: PMC10679410 DOI: 10.3389/fbioe.2023.1281503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023] Open
Abstract
Background: Deep Vein Thrombosis (DVT) is a common disease, frequently afflicting the lower limb veins of bedridden patients. Intermittent Pneumatic Compression (IPC) is often employed as an effective solution for this problem. In our study, a random selection of 264 patients underwent IPC treatment for either one or 8 hours daily. The rate of severe venous thrombosis was substantially reduced in the IPC-treated group compared to the control group. However, real-time monitoring of blood flow during IPC operation periods remains a challenge, leading to rare awareness of IPC working mechanism on thrombosis prevention. Methods: Here, microfluidic chip methodology is used to create an in vitro vein-mimicking platform integrating venous valves in a deformable channel. Whole blood of patients after knee surgery was perfused into the venous channel at a controlled flow rate obtained from patients with IPC treatment clinically. Results: According to the numerical simulations results, both of an increase in compressive pressure and a decrease in time interval of IPC device can accelarete blood flow rate and the shear stress within the vein. The vein chip experiments also reveal that the fibrin accumulation can be greatly lowered in IPC treated group, indicating less thrombosis formation in future. A time interval of 24 seconds and a maximum contraction pressure of 40 mmHg were proved to be the most effective parameters for the IPC device adopted in our clinical trail. Conclusion: This vein chip presents a novel method for observing the functional mechanisms of IPC device for DVT prevention. It provides crucial data for further standardization and optimization of IPC devices in clinical usage.
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Affiliation(s)
- Hongtao Dai
- Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing, China
| | - Senlin Chai
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Drum Tower Hospital Affiliated to Medical School of Nanjing University, Nanjing University, Nanjing, China
| | - Yao Yao
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Drum Tower Hospital Affiliated to Medical School of Nanjing University, Nanjing University, Nanjing, China
| | - Wenlai Tang
- Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing, China
- Guangdong Key Laboratory of Minimally Invasive Surgical Instruments and Manufacturing Technology, School of Electromechanically Engineering, Guangdong University of Technology, Guangzhou, China
| | - Jianping Shi
- Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing, China
| | - Qing Jiang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Drum Tower Hospital Affiliated to Medical School of Nanjing University, Nanjing University, Nanjing, China
| | - Liya Zhu
- Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing, School of Electrical and Automation Engineering, Nanjing Normal University, Nanjing, China
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4
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Chooklin S, Chuklin S. PATHOPHYSIOLOGICAL MECHANISMS OF DEEP VEIN THROMBOSIS. FIZIOLOHICHNYĬ ZHURNAL 2023; 69:133-144. [DOI: 10.15407/fz69.06.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Deep venous thrombosis is a frequent multifactorial disease and most of the time is triggered by the interaction between acquired risk factors, particularly immobility, and hereditary risk factors such as thrombophilias. The mechanisms underlying deep venous thrombosis are not fully elucidated; however, in recent years the role of venous flow, endothelium, platelets, leukocytes, and the interaction between inflammation and hemostasis has been determined. Alteration of venous blood flow produces endothelial activation, favoring the adhesion of platelets and leukocytes, which, through tissue factor expression and neutrophil extracellular traps formation, contribute to the activation of coagulation, trapping more cells, such as red blood cells, monocytes, eosinophils, lymphocytes. The coagulation factor XI-driven propagation phase of blood coagulation plays a major role in venous thrombus growth, but a minor role in hemostasis. In this work, the main mechanisms involved in the pathophysiology of deep vein thrombosis are described.
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Chen L, Yu L, Liu Y, Xu H, Li W, Wang F, Zhu J, Yi K, Ma L, Xiao H, Zhou F, Chen M, Cheng Y, Wang F, Zhu C, Xiao X, Yang Y. Valve-Adjustable Optofluidic Bio-Imaging Platform for Progressive Stenosis Investigation. ACS Sens 2023; 8:3104-3115. [PMID: 37477650 DOI: 10.1021/acssensors.3c00754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
The clinical evidence has proven that valvular stenosis is closely related to many vascular diseases, which attracts great academic attention to the corresponding pathological mechanisms. The investigation is expected to benefit from the further development of an in vitro model that is tunable for bio-mimicking progressive valvular stenosis and enables accurate optical recognition in complex blood flow. Here, we develop a valve-adjustable optofluidic bio-imaging recognition platform to fulfill it. Specifically, the bionic valve was designed with in situ soft membrane, and the internal air-pressure chamber could be regulated from the inside out to bio-mimic progressive valvular stenosis. The developed imaging algorithm enhances the recognition of optical details in blood flow imaging and allows for quantitative analysis. In a prospective clinical study, we examined the effect of progressive valvular stenosis on hemodynamics within the typical physiological range of veins by this way, where the inhomogeneity and local enhancement effect in the altered blood flow field were precisely described and the optical differences were quantified. The effectiveness and consistency of the results were further validated through statistical analysis. In addition, we tested it on fluorescence and noticed its good performance in fluorescent tracing of the clotting process. In virtue of theses merits, this system should be able to contribute to mechanism investigation, pharmaceutical development, and therapeutics of valvular stenosis-related diseases.
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Affiliation(s)
- Longfei Chen
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
- Shenzhen Research Institute, Wuhan University, Shenzhen 518000, China
| | - Le Yu
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Yantong Liu
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Hongshan Xu
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Wei Li
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Fang Wang
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Jiaomeng Zhu
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
| | - Kezhen Yi
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, China
| | - Linlu Ma
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, China
| | - Hui Xiao
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, China
| | - Fuling Zhou
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, China
| | - Ming Chen
- Department of Blood Transfusion, Zhongnan Hospital, Wuhan University, Wuhan 430071, China
| | - Yanxiang Cheng
- School of Medicine, Renmin Hospital, Wuhan University, Wuhan 430060, China
| | - Fubing Wang
- Department of Laboratory Medicine, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan 430071, China
| | - Chengliang Zhu
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Xuan Xiao
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Yi Yang
- Department of Clinical Laboratory, Institute of Medicine and Physics, Renmin Hospital of Wuhan University, Key Laboratory of Artificial Micro- and Nano- Structures of Ministry of Education, School of Physics & technology, Wuhan University, Wuhan 430072, China
- Shenzhen Research Institute, Wuhan University, Shenzhen 518000, China
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Li Y, Li Y, Li J, Chen H. Wall shear gradient dependent thrombosis studied in blood-on-a-chip with stenotic, branched, and valvular constructions. BIOMICROFLUIDICS 2023; 17:034101. [PMID: 37187669 PMCID: PMC10171887 DOI: 10.1063/5.0149884] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/19/2023] [Indexed: 05/17/2023]
Abstract
Thrombosis is the leading cause of death, while the effect of the shear flow on the formation of thrombus in vascular constructions has not been thoroughly understood, and one of the challenges is to observe the origination of thrombus with a controlled flow field. In this work, we use blood-on-a-chip technology to mimic the flow conditions in coronary artery stenosis, neonatal aortic arch, and deep venous valve. The flow field is measured by the microparticle image velocimeter (μPIV). In the experiment, we find that the thrombus often originates at the constructions of stenosis, bifurcation, and the entrance of valve, where the flow stream lines change suddenly, and the maximum wall shear rate gradient appears. Using the blood-on-a-chip technology, the effect of the wall shear rate gradients on the formation of the thrombus has been illustrated, and the blood-on-a-chip is demonstrated to be a perspective tool for further studies on the flow-induced formation of thrombosis.
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Affiliation(s)
- Yan Li
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Yongjian Li
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
| | - Jiang Li
- School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Haosheng Chen
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
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7
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Baksamawi HA, Alexiadis A, Vigolo D, Brill A. Platelet accumulation in an endothelium-coated elastic vein valve model of deep vein thrombosis is mediated by GPIb α-VWF interaction. Front Cardiovasc Med 2023; 10:1167884. [PMID: 37180784 PMCID: PMC10174463 DOI: 10.3389/fcvm.2023.1167884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 03/28/2023] [Indexed: 05/16/2023] Open
Abstract
Deep vein thrombosis is a life-threatening disease that takes millions of people's lives worldwide. Given both technical and ethical issues of using animals in research, it is necessary to develop an appropriate in vitro model that would recapitulate the conditions of venous thrombus development. We present here a novel microfluidics vein-on-a-chip with moving valve leaflets to mimic the hydrodynamics in a vein, and Human Umbilical Vein Endothelial Cell (HUVEC) monolayer. A pulsatile flow pattern, typical for veins, was used in the experiments. Unstimulated human platelets, reconstituted with the whole blood, accumulated at the luminal side of the leaflet tips proportionally to the leaflet flexibility. Platelet activation by thrombin induced robust platelet accrual at the leaflet tips. Inhibition of glycoprotein (GP) IIb-IIIa did not decrease but, paradoxically, slightly increased platelet accumulation. In contrast, blockade of the interaction between platelet GPIbα and A1 domain of von Willebrand factor completely abolished platelet deposition. Stimulation of the endothelium with histamine, a known secretagogue of Weibel-Palade bodies, promoted platelet accrual at the basal side of the leaflets, where human thrombi are usually observed. Thus, platelet deposition depends on the leaflet flexibility, and accumulation of activated platelets at the valve leaflets is mediated by GPIbα-VWF interaction.
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Affiliation(s)
- Hosam Alden Baksamawi
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Alessio Alexiadis
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
- School of Biomedical Engineering, The University of Sydney, Sydney, NSW, Australia
| | - Daniele Vigolo
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
- School of Biomedical Engineering, The University of Sydney, Sydney, NSW, Australia
- The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW, Australia
| | - Alexander Brill
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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Sanchez ZAC, Vijayananda V, Virassammy DM, Rosenfeld L, Ramasubramanian AK. The interaction of vortical flows with red cells in venous valve mimics. BIOMICROFLUIDICS 2022; 16:024103. [PMID: 35282036 PMCID: PMC8896891 DOI: 10.1063/5.0078337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/08/2022] [Indexed: 06/14/2023]
Abstract
The motion of cells orthogonal to the direction of main flow is of importance in natural and engineered systems. The lateral movement of red blood cells (RBCs) distal to sudden expansion is considered to influence the formation and progression of thrombosis in venous valves, aortic aneurysms, and blood-circulating devices and is also a determining parameter for cell separation applications in flow-focusing microfluidic devices. Although it is known that the unique geometry of venous valves alters the blood flow patterns and cell distribution in venous valve sinuses, the interactions between fluid flow and RBCs have not been elucidated. Here, using a dilute cell suspension in an in vitro microfluidic model of a venous valve, we quantified the spatial distribution of RBCs by microscopy and image analysis, and using micro-particle image velocimetry and 3D computational fluid dynamics simulations, we analyzed the complex flow patterns. The results show that the local hematocrit in the valve pockets is spatially heterogeneous and is significantly different from the feed hematocrit. Above a threshold shear rate, the inertial separation of streamlines and lift forces contribute to an uneven distribution of RBCs in the vortices, the entrapment of RBCs in the vortices, and non-monotonic wall shear stresses in the valve pockets. Our experimental and computational characterization provides insights into the complex interactions between fluid flow, RBC distribution, and wall shear rates in venous valve mimics, which is of relevance to understanding the pathophysiology of thrombosis and improving cell separation efficiency.
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Effect of surfactant addition and viscosity of the continuous phase on flow fields and kinetics of drop formation in a flow-focusing microfluidic device. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2021.117183] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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10
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Abstract
This work proposes a model of particle agglomeration in elastic valves replicating the geometry and the fluid dynamics of a venous valve. The fluid dynamics is simulated with Smooth Particle Hydrodynamics, the elastic leaflets of the valve with the Lattice Spring Model, while agglomeration is modelled with a 4-2 Lennard-Jones potential. All the models are combined together within a single Discrete Multiphysics framework. The results show that particle agglomeration occurs near the leaflets, supporting the hypothesis, proposed in previous experimental work, that clot formation in deep venous thrombosis is driven by the fluid dynamics in the valve.
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Soltany Sadrabadi M, Hedayat M, Borazjani I, Arzani A. Fluid-structure coupled biotransport processes in aortic valve disease. J Biomech 2021; 117:110239. [PMID: 33515904 DOI: 10.1016/j.jbiomech.2021.110239] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 10/22/2020] [Accepted: 01/04/2021] [Indexed: 12/28/2022]
Abstract
Biological transport processes near the aortic valve play a crucial role in calcific aortic valve disease initiation and bioprosthetic aortic valve thrombosis. Hemodynamics coupled with the dynamics of the leaflets regulate these transport patterns. Herein, two-way coupled fluid-structure interaction (FSI) simulations of a 2D bicuspid aortic valve and a 3D mechanical heart valve were performed and coupled with various convective mass transport models that represent some of the transport processes in calcification and thrombosis. Namely, five different continuum transport models were developed to study biochemicals that originate from the blood and the leaflets, as well as residence-time and flow stagnation. Low-density lipoprotein (LDL) and platelet activation were studied for their role in calcification and thrombosis, respectively. Coherent structures were identified using vorticity and Lagrangian coherent structures (LCS) for the 2D and 3D models, respectively. A very close connection between vortex structures and biochemical concentration patterns was shown where different vortices controlled the concentration patterns depending on the transport mechanism. Additionally, the relationship between leaflet concentration and wall shear stress was revealed. Our work shows that blood flow physics and coherent structures regulate the flow-mediated biological processes that are involved in aortic valve calcification and thrombosis, and therefore could be used in the design process to optimize heart valve replacement durability.
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Affiliation(s)
| | - Mohammadali Hedayat
- J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, USA
| | - Iman Borazjani
- J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, USA
| | - Amirhossein Arzani
- Department of Mechanical Engineering, Northern Arizona University, Flagstaff, AZ, USA.
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