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Goodin MS, Miyagi C, Kuban BD, Flick CR, Polakowski AR, Karimov JH, Fukamachi K. Improving hydraulic performance of the left atrial assist device using computational fluid dynamics. Artif Organs 2024. [PMID: 39238204 DOI: 10.1111/aor.14850] [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: 02/02/2024] [Revised: 06/29/2024] [Accepted: 08/09/2024] [Indexed: 09/07/2024]
Abstract
BACKGROUND The left atrial assist device (LAAD) is a novel continuous-flow pump designed to treat patients with heart failure with preserved ejection fraction, a growing type of heart failure, but with limited device-treatment options. The LAAD is implanted in the mitral plane and pumps blood from the left atrium into the left ventricle. The purpose of this study was to refine the initial design of the LAAD, using results from computational fluid dynamics (CFD) analyses to inform changes that could improve hydraulic performance and flow patterns within the LAAD. METHODS The initial design and three variations were simulated, exploring changes to the primary impeller blades, the housing shape, and the number, size, and curvature of the diffuser vanes. Several pump rotational speeds and flow rates spanning the intended range of use were modeled. RESULTS Guided by the insight gained from each design iteration, the final design incorporated impeller blades with improved alignment relative to the incoming flow and wider, more curved diffuser vanes that better aligned with the approaching flow from the volute. These design adjustments reduced flow separation within the impeller and diffuser regions. In vitro testing confirmed the CFD predicted improvement in the hydraulic performance of the revised LAAD flow path design. CONCLUSIONS The CFD results from this study provided insight into the key pump design-related parameters that can be adjusted to improve the LAAD's hydraulic performance and internal flow patterns. This work also provided a foundation for future studies assessing the LAAD's biocompatibility under clinical conditions.
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Affiliation(s)
| | - Chihiro Miyagi
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Barry D Kuban
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Shared Laboratory Resources, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA
| | - Christine R Flick
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Anthony R Polakowski
- Shared Laboratory Resources, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jamshid H Karimov
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA
| | - Kiyotaka Fukamachi
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland, Ohio, USA
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Wagner MS, Kranz M, Krenkel L, Pointner D, Foltan M, Lubnow M, Lehle K. Computer based visualization of clot structures in extracorporeal membrane oxygenation and histological clot investigations for understanding thrombosis in membrane lungs. Front Med (Lausanne) 2024; 11:1416319. [PMID: 38962744 PMCID: PMC11219572 DOI: 10.3389/fmed.2024.1416319] [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: 04/12/2024] [Accepted: 06/06/2024] [Indexed: 07/05/2024] Open
Abstract
Extracorporeal membrane oxygenation (ECMO) was established as a treatment for severe cardiac or respiratory disease. Intra-device clot formation is a common risk. This is based on complex coagulation phenomena which are not yet sufficiently understood. The objective was the development and validation of a methodology to capture the key properties of clots deposed in membrane lungs (MLs), such as clot size, distribution, burden, and composition. One end-of-therapy PLS ML was examined. Clot detection was performed using multidetector computed tomography (MDCT), microcomputed tomography (μCT), and photography of fiber mats (fiber mat imaging, FMI). Histological staining was conducted for von Willebrand factor (vWF), platelets (CD42b, CD62P), fibrin, and nucleated cells (4', 6-diamidino-2-phenylindole, DAPI). The three imaging methods showed similar clot distribution inside the ML. Independent of the imaging method, clot loading was detected predominantly in the inlet chamber of the ML. The μCT had the highest accuracy. However, it was more expensive and time consuming than MDCT or FMI. The MDCT detected the clots with low scanning time. Due to its lower resolution, it only showed clotted areas but not the exact shape of clot structures. FMI represented the simplest variant, requiring little effort and resources. FMI allowed clot localization and calculation of clot volume. Histological evaluation indicated omnipresent immunological deposits throughout the ML. Visually clot-free areas were covered with leukocytes and platelets forming platelet-leukocyte aggregates (PLAs). Cells were embedded in vWF cobwebs, while vWF fibers were negligible. In conclusion, the presented methodology allowed adequate clot identification and histological classification of possible thrombosis markers such as PLAs.
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Affiliation(s)
- Maria S. Wagner
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Michael Kranz
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Lars Krenkel
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Daniel Pointner
- Department of Biofluid Mechanics, Faculty of Mechanical Engineering, Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
- Regensburg Center of Biomedical Engineering, Facility of University Regensburg and Technical University of Applied Sciences (OTH) Regensburg, Regensburg, Germany
| | - Maik Foltan
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
| | - Matthias Lubnow
- Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Karla Lehle
- Department of Cardiothoracic Surgery, University Hospital Regensburg, Regensburg, Germany
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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.
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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.
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Menallo G, Miraglia R, Gerasia R, Cosentino F, Terranova P, Barbuto M, Wagner WR, D'Amore A. Open-Source Image-Based Tool to Experimentally Evaluate Blood Residence Time in Clinical Devices. ASAIO J 2024; 70:451-455. [PMID: 38237575 DOI: 10.1097/mat.0000000000002138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024] Open
Abstract
This article introduces an open-source tool to experimentally compare blood residence time in biomedical devices using an image-based method. The experimental setup and the postprocessing workflow are comprehensively elucidated in a detailed report that conducts a thorough comparison of the residence times of a blood analog within three distinct blood oxygenator prototypes. To enable widespread accessibility and ease of use, the user-friendly MATLAB App developed for the analysis is available on the Mathworks repository: https://www.mathworks.com/matlabcentral/fileexchange/135156 .
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Affiliation(s)
- Giorgio Menallo
- From the Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Roberto Miraglia
- Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione, Palermo, Italy
| | - Roberta Gerasia
- Istituto Mediterraneo per i Trapianti e Terapie ad Alta Specializzazione, Palermo, Italy
| | | | - Pietro Terranova
- Department of Engineering, University of Palermo, Palermo, Italy
| | - Marianna Barbuto
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
| | - William R Wagner
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
- Clinical Translational Science Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Antonio D'Amore
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
- Ri.MED Foundation, Palermo, Italy
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
- Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
- Clinical Translational Science Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
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Wickramarachchi A, Gregory SD, Burrell AJC, Khamooshi M. Flow characterization of Maquet and Bio-Medicus multi-stage drainage cannulae during venoarterial extracorporeal membrane oxygenation. Comput Biol Med 2024; 171:108135. [PMID: 38373368 DOI: 10.1016/j.compbiomed.2024.108135] [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: 12/06/2023] [Revised: 01/15/2024] [Accepted: 02/12/2024] [Indexed: 02/21/2024]
Abstract
BACKGROUND Drainage cannulae extract blood from a patient during venoarterial extracorporeal membrane oxygenation (VA ECMO), a treatment that temporarily supports patients undergoing severe heart and/or lung dysfunction. Currently, the two most commonly used multi-stage drainage cannulae are manufactured by Maquet and Bio-Medicus, but their designs vary in many aspects which impacts the generated flow dynamics. Therefore, this study aimed to use computational fluid dynamics (CFD) to explore the flow characteristics of the aforementioned cannulae and their impact on complications such as thrombosis. METHODS The Maquet and Bio-Medicus cannulae were 3D modelled within a patient-specific geometry of the venous vasculature taken from a computed tomography scan of a patient undergoing VA ECMO. A drainage flow rate of 4 L/min was assigned to each cannula. Lastly, a stress blended eddy simulation turbulence model was employed to resolve bulk flow turbulence. RESULTS The proximal row of side holes in both cannulae generated high intensity counter-rotating vortices, thus generating supraphysiological shear. These proximal rows were also responsible for the majority of flow extraction in both cannulae (>1.6 L/min). Despite identical simulation settings, each cannulae had differing impacts on global flow dynamics. For instance, the Bio-Medicus model produced a total stagnant blood volume of 25.6 ml, compared to 17.8 ml the Maquet cannula, thereby increasing the risk of thrombosis. CONCLUSIONS Overall, our results demonstrate that differences in design clearly impact flow dynamics and risk of complications. Therefore, further work in optimizing cannula design may be beneficial to prevent harmful flow characteristics.
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Affiliation(s)
- Avishka Wickramarachchi
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia.
| | - Shaun D Gregory
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia
| | - Aidan J C Burrell
- Department of Intensive Care, Alfred Hospital, 55 Commercial Road, Melbourne, VIC, Australia; Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia
| | - Mehrdad Khamooshi
- Cardio-Respiratory Engineering and Technology Laboratory, Department of Mechanical and Aerospace Engineering, Monash University, 631 Blackburn Road, Clayton, VIC, Australia
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Burgreen GW, Zhussupbekov M, Rojano RM, Antaki JF. Exploratory Simulation of Thrombosis in a Temporary LVAD Catheter Pump within a Virtual In-vivo Left Heart Environment. ARXIV 2023:arXiv:2312.04761v1. [PMID: 38106454 PMCID: PMC10723545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Percutaneous catheter pumps are intraventricular temporary mechanical circulatory support (MCS) devices that are positioned across the aortic valve into the left ventricle (LV) and provide continuous antegrade blood flow from the LV into the ascending aorta (AA). MCS devices are most often computationally evaluated as isolated devices subject to idealized steady-state blood flow conditions. In clinical practice, MCS devices operate connected to or within diseased pulsatile native hearts and are often complicated by hemocompatibility related adverse events such as stroke, bleeding, and thrombosis. Whereas aspects of the human circulation are increasingly being simulated via computational methods, the precise interplay of pulsatile LV hemodynamics with MCS pump hemocompatibility remains mostly unknown and not well characterized. Technologies are rapidly converging such that next-generation MCS devices will soon be evaluated in virtual physiological environments that increasingly mimic clinical settings. The purpose of this brief communication is to report results and lessons learned from an exploratory CFD simulation of hemodynamics and thrombosis for a catheter pump situated within a virtual in-vivo left heart environment.
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Affiliation(s)
- Greg W Burgreen
- Center for Advanced Vehicular Systems, Mississippi State University, Starkville, MS
| | | | | | - James F Antaki
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY
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7
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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.
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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
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8
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Sun X, Li S, He Y, Liu Y, Ma T, Zeng R, Liu Z, Chen Y, Zheng Y, Liu X. Effects of cardiac function alterations on the risk of postoperative thrombotic complications in patients receiving endovascular aortic repair. Front Physiol 2023; 13:1114110. [PMID: 36703931 PMCID: PMC9871241 DOI: 10.3389/fphys.2022.1114110] [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: 12/02/2022] [Accepted: 12/28/2022] [Indexed: 01/11/2023] Open
Abstract
Introduction: Chronic heart disease (CHD) is a common comorbidity of patients receiving endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA). The explicit relationship between ventricular systolic function and EVAR complication of thrombotic events is unknown. Methods: In this study, we proposed a three-dimensional numerical model coupled with the lumped-elements heart model, which is capable of simulating thrombus formation in diverse systolic functions. The relation of cardiac functions and the predicted risk of thrombus formation in the aorta and/or endograft of 4 patients who underwent EVAR was investigated. Relative risks for thrombus formation were identified using machine-learning algorithms. Results: The computational results demonstrate that thrombus tended to form on the interior side of the aorta arch and iliac branches, and cardiac function can affect blood flow field and affect thrombus formation, which is consistent with the four patients' post-operative imaging follow-up. We also found that RRT, OSI, TAWSS in thrombosis area are lower than whole average. In addition, we found that the thrombus formation has negative correlations with the maximum ventricular contractile force (r = -.281 ± .101) and positive correlations with the minimum ventricular contractile force (r = .238 ± .074), whereas the effect of heart rate (r = -.015 ± .121) on thrombus formation is not significant. Conclusion: In conclusion, changes in ventricular systolic function may alter the risk of thrombotic events after EVAR repair, which could provide insight into the selection of adjuvant therapy strategies for AAA patients with CHD.
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Affiliation(s)
- Xiaoning Sun
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China,Department, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Siting Li
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China,Department, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Yuan He
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Yuxi Liu
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Tianxiang Ma
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Rong Zeng
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Zhili Liu
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Yu Chen
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
| | - Yuehong Zheng
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China,Department, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China,*Correspondence: Yuehong Zheng, ; Xiao Liu,
| | - Xiao Liu
- Key Laboratory of Biomechanics and Mechanobiology, Ministry of Education, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, China,*Correspondence: Yuehong Zheng, ; Xiao Liu,
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