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Atari M, Saroukhani A, Manshaei M, Bateni P, Zargar Kharazi A, Vatankhah E, Haghjooy Javanmard S. Preclinical in vivo assessment of a cell-free multi-layered scaffold prepared by 3D printing and electrospinning for small-diameter blood vessel tissue engineering in a canine model. Biomater Sci 2023; 11:6871-6880. [PMID: 37646468 DOI: 10.1039/d3bm00642e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Tissue-engineered vascular grafts (TEVGs) are promising alternatives to existing prosthetic grafts. The objective of this study is to evaluate the clinical feasibility of a novel multi-layered small-diameter vascular graft that has a hierarchical structure. Vascular grafts with elaborately designed composition and architecture were prepared by 3D printing and electrospinning and were implanted into the femoral artery of 5 dogs. The patency of the grafts was assessed using Doppler ultrasonography. After 6 months, the grafts were retrieved and histological and SEM examinations were conducted. During implantation, the grafts exhibited resistance to kinking and no blood seepage thanks to the helical structure of the innermost and outermost layers. The grafts showed a high patency rate and remodelling ability. At 6 months post-implantation, the lumen was endothelialized and middle layers were regenerated by infiltration of smooth muscle cells (SMCs) and deposition of extracellular matrix (ECM). These results suggest that the multi-layered vascular graft may be a promising candidate for small-diameter blood vessel tissue engineering in clinical practice.
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Affiliation(s)
- Mehdi Atari
- Applied Physiology Research Centre, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, 81686-55477, Iran.
| | - Abbas Saroukhani
- Department of Surgery, School of Medicine, Al-Zahra Hospital, Isfahan University of Medical Sciences, Isfahan, 81746-73461, Iran
| | - Maziar Manshaei
- Animal Laboratory and Dental Research Centre, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, 81746-73461, Iran
| | - Peiman Bateni
- Animal Laboratory and Dental Research Centre, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, 81746-73461, Iran
| | - Anousheh Zargar Kharazi
- Applied Physiology Research Centre, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, 81686-55477, Iran.
- Department of Biomaterials, Nanotechnology and Tissue Engineering, School of Advanced Medical Technology, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Elham Vatankhah
- Department of Biosystems, Faculty of New Technologies and Aerospace Engineering, Shahid Beheshti University, Tehran, Iran.
| | - Shaghayegh Haghjooy Javanmard
- Applied Physiology Research Centre, Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, 81686-55477, Iran.
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Patient-specific computational haemodynamics associated with the surgical creation of an arteriovenous fistula. Med Eng Phys 2022; 105:103814. [DOI: 10.1016/j.medengphy.2022.103814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 11/22/2022]
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Lee R, Stoddart M, Dyson I, Cassimjee I, Handa A, Cheng CP. Length Redundancy and Twist Improve the Biomechanical Properties of Polytetrafluoroethylene Bypass Grafts. Ann Vasc Surg 2019; 61:410-415. [PMID: 31319171 PMCID: PMC6900574 DOI: 10.1016/j.avsg.2019.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 02/23/2019] [Accepted: 04/18/2019] [Indexed: 10/29/2022]
Abstract
BACKGROUND The iliofemoropopliteal artery significantly changes path length during normal hip and knee flexion. Prosthetic bypass grafts, such as polytetrafluoroethylene (PTFE) grafts, are relatively stiff and thus can subject graft anastomoses to high tension when the path length increases. The aim of this study was to examine the influence of length redundancy and twist on the biomechanical properties of PTFE bypass grafts. METHODS Unreinforced and ring-reinforced PTFE grafts were loaded in an axial mechanical testing machine to measure the tensile and compressive axial forces with varying levels of length redundancy and axial twist. RESULTS Adding 5-15% length redundancy to a graft decreases the force to cause 5% extension by > 90% without substantially increasing shortening forces. Adding 4.5°/cm of axial twist imparts a corkscrew shape to the graft without increasing extension or shortening forces in the presence of length redundancy. Ring-reinforced PTFE grafts require more length redundancy to experience these reductions in forces especially in the presence of axial twist. CONCLUSIONS A modest amount of length redundancy and twist (i.e., a cork-screw condition) confers improved biomechanical properties in a PTFE graft, especially in ring-reinforced grafts. This should be taken into consideration when fashioning an arterial bypass graft in the iliofemoropopliteal segment.
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Affiliation(s)
- Regent Lee
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, Oxfordshire, UK.
| | - Miranda Stoddart
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, Oxfordshire, UK
| | - Igor Dyson
- Department of Engineering Science, University of Oxford, Oxford, Oxfordshire, UK
| | - Ismail Cassimjee
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, Oxfordshire, UK
| | - Ashok Handa
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, Oxfordshire, UK
| | - Christopher P Cheng
- Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, Oxfordshire, UK; Department of Vascular Surgery, Stanford University, Palo Alto, CA.
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Efficiently Generating Mixing by Combining Differing Small Amplitude Helical Geometries. FLUIDS 2019. [DOI: 10.3390/fluids4020059] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Helical geometries have been used in recent years to form cardiovascular prostheses such as stents and shunts. The helical geometry has been found to induce swirling flow, promoting in-plane mixing. This is hypothesised to reduce the formation of thrombosis and neo-intimal hyperplasia, in turn improving device patency and reducing re-implantation rates. In this paper we investigate whether joining together two helical geometries, of differing helical radii, in a repeating sequence, can produce significant gains in mixing effectiveness, by embodying a ‘streamline crossing’ flow environment. Since the computational cost of calculating particle trajectories over extended domains is high, in this work we devised a procedure for efficiently exploring the large parameter space of possible geometry combinations. Velocity fields for the single geometries were first obtained using the spectral/hp element method. These were then discontinuously concatenated, in series, for the particle tracking based mixing analysis of the combined geometry. Full computations of the most promising combined geometries were then performed. Mixing efficiency was evaluated quantitatively using Poincaré sections, particle residence time data, and information entropy. Excellent agreement was found between the idealised (concatenated flow field) and the full simulations of mixing performance, revealing that a strict discontinuity between velocity fields is not required for mixing enhancement, via streamline crossing, to occur. Optimal mixing was found to occur for the combination R = 0.2 D and R = 0.5 D , producing a 70 % increase in mixing, compared with standard single helical designs. The findings of this work point to the benefits of swirl disruption and suggest concatenation as an efficient means to determine optimal configurations of repeating geometries for future designs of vascular prostheses.
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Prashantha B, Anish S. Computational investigations on the hemodynamic performance of a new swirl generator in bifurcated arteries. Comput Methods Biomech Biomed Engin 2019; 22:364-375. [DOI: 10.1080/10255842.2018.1556974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- B. Prashantha
- Department of Mechanical Engineering, M S Ramaiah Institute of Technology, Bengaluru, Karnataka, India
| | - S. Anish
- Advanced Fluid Mechanics Laboratory, Department of Mechanical Engineering, National Institute of Technology, Surathkal, Karnataka, India
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Discrete-Phase Modelling of an Asymmetric Stenosis Artery Under Different Womersley Numbers. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2019. [DOI: 10.1007/s13369-018-3391-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Li Y, Shi G, Du J, Wang J, Bian P. Analysis and preparation of rotational flow mechanism of artificial blood vessel with spiral folds on inner wall. Biomech Model Mechanobiol 2018; 18:411-423. [DOI: 10.1007/s10237-018-1092-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/29/2018] [Indexed: 10/27/2022]
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Ha H, Koo HJ, Huh HK, Kim GB, Kweon J, Kim N, Kim YH, Kang JW, Lim TH, Song JK, Lee SJ, Yang DH. Effect of pannus formation on the prosthetic heart valve: In vitro demonstration using particle image velocimetry. PLoS One 2018; 13:e0199792. [PMID: 29953485 PMCID: PMC6023143 DOI: 10.1371/journal.pone.0199792] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 06/13/2018] [Indexed: 02/06/2023] Open
Abstract
Although hemodynamic influence of the subprosthetic tissue, termed as pannus, may contribute to prosthetic aortic valve dysfunction, the relationship between pannus extent and hemodynamics in the prosthetic valve has rarely been reported. We investigated the fluid dynamics of pannus formation using in vitro experiments with particle image velocimetry. Subvalvular pannus formation caused substantial changes in prosthetic valve transvalvular peak velocity, transvalvular pressure gradient (TPG) and opening angle. Maximum flow velocity and corresponding TPG were mostly affected by pannus width. When the pannus width was 25% of the valve diameter, pannus formation elevated TPG to >2.5 times higher than that without pannus formation. Opening dysfunction was observed only for a pannus involvement angle of 360°. Although circumferential pannus with an involvement angle of 360° decreased the opening angle of the valve from approximately 82° to 58°, eccentric pannus with an involvement angle of 180° did not induce valve opening dysfunction. The pannus involvement angle largely influenced the velocity flow field at the aortic sinus and corresponding hemodynamic indices, including wall shear stress, principal shear stress and viscous energy loss distributions. Substantial discrepancy between the velocity-based TPG estimation and direct pressure measurements was observed for prosthetic valve flow with pannus formation.
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Affiliation(s)
- Hojin Ha
- Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon, South Korea
| | - Hyun Jung Koo
- Department of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Hyung Kyu Huh
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, South Korea
| | - Guk Bae Kim
- Asan Institute of Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Jihoon Kweon
- Department of Cardiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Namkug Kim
- Department of Convergence Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Young-Hak Kim
- Department of Cardiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Joon-Won Kang
- Department of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Tae-Hwan Lim
- Department of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Jae-Kwan Song
- Department of Cardiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Sang Joon Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, South Korea
| | - Dong Hyun Yang
- Department of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
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Chen Y, Deng X, Shan X, Xing Y. Study of helical flow inducers with different thread pitches and diameters in vena cava. PLoS One 2018; 13:e0190609. [PMID: 29298357 PMCID: PMC5752007 DOI: 10.1371/journal.pone.0190609] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 12/18/2017] [Indexed: 11/25/2022] Open
Abstract
Pulmonary embolism is a severe, potentially life-threatening condition. Inferior vena cava filters have been used to prevent recurrent pulmonary embolisms. However, the build-up of thrombosis in vena cava filters after deployment presents a severe problem to patients. Previous studies proposed that filters with helical flow are beneficial and capable of alleviating this problem. In this study, the hemodynamic performances of four typical helical flow inducers in the vena cava are determined using computational fluid dynamics simulations (steady-state and pulsatile flow) and compared. Pilot in vitro experiments were also conducted. The simulation results demonstrate that large-diameter inducers produce helical flow. Among inducers with identical diameter, those with a smaller thread pitch are more likely to induce increased helical flow. We also observed that the small thread pitch inducers can yield higher shear rates. Furthermore, a large diameter, small thread pitch helical flow inducer increases the time-averaged wall shear stress and reduces the oscillating shear index and relative residence time on the vessel wall in the vicinity of the helical flow inducer. In vitro experiments also verify that large diameter inducers generate a helical flow. A notable observation of this study is that the diameter is the key parameter that affects the induction of a helical flow. This study will likely provide important guidance for the design of interventional treatments and the deployment of filters associated with helical flow in the vena cava.
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Affiliation(s)
- Ying Chen
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China
| | - Xiaoyan Deng
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China
- * E-mail:
| | - Xinying Shan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
- Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China
| | - Yubin Xing
- Department of Infection Management and Disease Control, The General Hospital of People’s Liberation Army, Beijing, China
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Choi W, Park SH, Huh HK, Lee SJ. Hemodynamic characteristics of flow around a deformable stenosis. J Biomech 2017; 61:216-223. [PMID: 28835343 DOI: 10.1016/j.jbiomech.2017.07.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 06/06/2017] [Accepted: 07/22/2017] [Indexed: 10/19/2022]
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11
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Bioinspired helical graft with taper to enhance helical flow. J Biomech 2016; 49:3643-3650. [DOI: 10.1016/j.jbiomech.2016.09.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 09/09/2016] [Accepted: 09/19/2016] [Indexed: 11/23/2022]
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12
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Estimation of turbulent kinetic energy using 4D phase-contrast MRI: Effect of scan parameters and target vessel size. Magn Reson Imaging 2016; 34:715-723. [DOI: 10.1016/j.mri.2016.03.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/17/2016] [Accepted: 03/03/2016] [Indexed: 11/18/2022]
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Kim BJ, Ha H, Huh HK, Kim GB, Kim JS, Kim N, Lee SJ, Kang DW, Kwon SU. Post-stenotic Recirculating Flow May Cause Hemodynamic Perforator Infarction. J Stroke 2015; 18:66-72. [PMID: 26687122 PMCID: PMC4747075 DOI: 10.5853/jos.2015.01445] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 10/05/2015] [Accepted: 10/17/2015] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND AND PURPOSE The primary mechanism underlying paramedian pontine infarction (PPI) is atheroma obliterating the perforators. Here, we encountered a patient with PPI in the post-stenotic area of basilar artery (BA) without a plaque, shown by high-resolution magnetic resonance imaging (HR-MRI). We performed an experiment using a 3D-printed BA model and a particle image velocimetry (PIV) to explore the hemodynamic property of the post-stenotic area and the mechanism of PPI. METHODS 3D-model of a BA stenosis was reconstructed with silicone compound using a 3D-printer based on the source image of HR-MRI. Working fluid seeded with fluorescence particles was used and the velocity of those particles was measured horizontally and vertically. Furthermore, microtubules were inserted into the posterior aspect of the model to measure the flow rates of perforators (pre-and post-stenotic areas). The flow rates were compared between the microtubules. RESULTS A recirculating flow was observed from the post-stenotic area in both directions forming a spiral shape. The velocity of the flow in these regions of recirculation was about one-tenth that of the flow in other regions. The location of recirculating flow well corresponded with the area with low-signal intensity at the time-of-flight magnetic resonance angiography and the location of PPI. Finally, the flow rate through the microtubule inserted into the post-stenotic area was significantly decreased comparing to others (P<0.001). CONCLUSIONS Perforator infarction may be caused by a hemodynamic mechanism altered by stenosis that induces a recirculation flow. 3D-printed modeling and PIV are helpful understanding the hemodynamics of intracranial stenosis.
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Affiliation(s)
- Bum Joon Kim
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Hojin Ha
- Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Korea
| | - Hyung Kyu Huh
- Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Korea
| | - Guk Bae Kim
- Asan Institute of Life Science, Asan Medical Center, Seoul, Korea
| | - Jong S Kim
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Namkug Kim
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.,Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sang-Joon Lee
- Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Korea
| | - Dong-Wha Kang
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sun U Kwon
- Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Lee SJ, Choi W, Seo E, Yeom E. Association of Early Atherosclerosis with Vascular Wall Shear Stress in Hypercholesterolemic Zebrafish. PLoS One 2015; 10:e0142945. [PMID: 26561854 PMCID: PMC4643039 DOI: 10.1371/journal.pone.0142945] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/28/2015] [Indexed: 11/18/2022] Open
Abstract
Although atherosclerosis is a multifactorial disease, the role of hemodynamic information has become more important. Low and oscillating wall shear stress (WSS) that changes its direction is associated with the early stage of atherosclerosis. Several in vitro and in vivo models were proposed to reveal the relation between the WSS and the early atherosclerosis. However, these models possess technical limitations in mimicking real physiological conditions and monitoring the developmental course of the early atherosclerosis. In this study, a hypercholesterolaemic zebrafish model is proposed as a novel experimental model to resolve these limitations. Zebrafish larvae are optically transparent, which enables temporal observation of pathological variations under in vivo condition. WSS in blood vessels of 15 days post-fertilisation zebrafish was measured using a micro particle image velocimetry (PIV) technique, and spatial distribution of lipid deposition inside the model was quantitatively investigated after feeding high cholesterol diet for 10 days. Lipids were mainly deposited in blood vessel of low WSS. The oscillating WSS was not induced by the blood flows in zebrafish models. The present hypercholesterolaemic zebrafish would be used as a potentially useful model for in vivo study about the effects of low WSS in the early atherosclerosis.
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Affiliation(s)
- Sang Joon Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang 790–784, Republic of Korea
- * E-mail:
| | - Woorak Choi
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang 790–784, Republic of Korea
| | - Eunseok Seo
- Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Dalseong, Daegu 711–873, Republic of Korea
| | - Eunseop Yeom
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Pohang 790–784, Republic of Korea
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Ha H, Choi W, Park H, Lee SJ. Effect of swirling blood flow on vortex formation at post-stenosis. Proc Inst Mech Eng H 2015; 229:175-83. [PMID: 25767153 DOI: 10.1177/0954411915573065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Various clinical observations reported that swirling blood flow is a normal physiological flow pattern in various vasculatures. The swirling flow has beneficial effects on blood circulation through the blood vessels. It enhances oxygen transfer and reduces low-density lipoprotein concentration in the blood vessel by enhancing cross-plane mixing of the blood. However, the fluid-dynamic roles of the swirling flow are not yet fully understood. In this study, inhibition of material deposition at the post-stenosis region by the swirling flow was observed. To reveal the underlying fluid-dynamic characteristics, pathline flow visualization and time-resolved particle image velocimetry measurements were conducted. Results showed that the swirling inlet flow increased the development of vortices at near wall region of the post-stenosis, which can suppress further development of stenosis by enhancing transport and mixing of the blood flow. The fluid-dynamic characteristics obtained in this study would be useful for improving hemodynamic characteristics of vascular grafts and stents in which the stenosis frequently occurred. Moreover, the time-resolved particle image velocimetry measurement technique and vortex identification method employed in this study would be useful for investigating the fluid-dynamic effects of the swirling flow on various vascular environments.
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Affiliation(s)
- Hojin Ha
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Woorak Choi
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Hanwook Park
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Sang Joon Lee
- Center for Biofluid and Biomimic Research, Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea
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Ha H, Choi W, Lee SJ. Beneficial fluid-dynamic features of pulsatile swirling flow in 45° end-to-side anastomosis. Med Eng Phys 2015; 37:272-9. [DOI: 10.1016/j.medengphy.2015.01.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 11/29/2014] [Accepted: 01/11/2015] [Indexed: 11/17/2022]
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