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Clift CL, Blaser MC, Gerrits W, Turner ME, Sonawane A, Pham T, Andresen JL, Fenton OS, Grolman JM, Campedelli A, Buffolo F, Schoen FJ, Hjortnaes J, Muehlschlegel JD, Mooney DJ, Aikawa M, Singh SA, Langer R, Aikawa E. Intracellular proteomics and extracellular vesiculomics as a metric of disease recapitulation in 3D-bioprinted aortic valve arrays. SCIENCE ADVANCES 2024; 10:eadj9793. [PMID: 38416823 PMCID: PMC10901368 DOI: 10.1126/sciadv.adj9793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 01/25/2024] [Indexed: 03/01/2024]
Abstract
In calcific aortic valve disease (CAVD), mechanosensitive valvular cells respond to fibrosis- and calcification-induced tissue stiffening, further driving pathophysiology. No pharmacotherapeutics are available to treat CAVD because of the paucity of (i) appropriate experimental models that recapitulate this complex environment and (ii) benchmarking novel engineered aortic valve (AV)-model performance. We established a biomaterial-based CAVD model mimicking the biomechanics of the human AV disease-prone fibrosa layer, three-dimensional (3D)-bioprinted into 96-well arrays. Liquid chromatography-tandem mass spectrometry analyses probed the cellular proteome and vesiculome to compare the 3D-bioprinted model versus traditional 2D monoculture, against human CAVD tissue. The 3D-bioprinted model highly recapitulated the CAVD cellular proteome (94% versus 70% of 2D proteins). Integration of cellular and vesicular datasets identified known and unknown proteins ubiquitous to AV calcification. This study explores how 2D versus 3D-bioengineered systems recapitulate unique aspects of human disease, positions multiomics as a technique for the evaluation of high throughput-based bioengineered model systems, and potentiates future drug discovery.
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Affiliation(s)
- Cassandra L Clift
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mark C Blaser
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Willem Gerrits
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Cardiothoracic Surgery, University Medical Center Utrecht, Utrecht, Netherlands
| | - Mandy E Turner
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Abhijeet Sonawane
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Tan Pham
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jason L Andresen
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Owen S Fenton
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Division of Pharmacoengineering and Molecular Pharmaceutics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Joshua M Grolman
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02134, USA
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
- Materials Science and Engineering, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Alesandra Campedelli
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Fabrizio Buffolo
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Internal Medicine and Hypertension Unite, Department of Medical Sciences, University of Torin, Turin, Italy
| | - Frederick J Schoen
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Jesper Hjortnaes
- Department of Cardiothoracic Surgery, Leiden University Medical Center (LUMC), Leiden, Netherlands
| | - Jochen D Muehlschlegel
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - David J Mooney
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02134, USA
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA 02115, USA
| | - Masanori Aikawa
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Cardiovascular Medicine, Department of Medicine, Center for Excellence in Vascular Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sasha A Singh
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Robert Langer
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Harvard and MIT Division of Health Science and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elena Aikawa
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Cardiovascular Medicine, Department of Medicine, Center for Excellence in Vascular Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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2
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Notenboom ML, Van Hoof L, Schuermans A, Takkenberg JJM, Rega FR, Taverne YJHJ. Aortic Valve Embryology, Mechanobiology, and Second Messenger Pathways: Implications for Clinical Practice. J Cardiovasc Dev Dis 2024; 11:49. [PMID: 38392263 PMCID: PMC10888685 DOI: 10.3390/jcdd11020049] [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: 12/24/2023] [Revised: 01/22/2024] [Accepted: 01/29/2024] [Indexed: 02/24/2024] Open
Abstract
During the Renaissance, Leonardo Da Vinci was the first person to successfully detail the anatomy of the aortic root and its adjacent structures. Ever since, novel insights into morphology, function, and their interplay have accumulated, resulting in advanced knowledge on the complex functional characteristics of the aortic valve (AV) and root. This has shifted our vision from the AV as being a static structure towards that of a dynamic interconnected apparatus within the aortic root as a functional unit, exhibiting a complex interplay with adjacent structures via both humoral and mechanical stimuli. This paradigm shift has stimulated surgical treatment strategies of valvular disease that seek to recapitulate healthy AV function, whereby AV disease can no longer be seen as an isolated morphological pathology which needs to be replaced. As prostheses still cannot reproduce the complexity of human nature, treatment of diseased AVs, whether stenotic or insufficient, has tremendously evolved, with a similar shift towards treatments options that are more hemodynamically centered, such as the Ross procedure and valve-conserving surgery. Native AV and root components allow for an efficient Venturi effect over the valve to allow for optimal opening during the cardiac cycle, while also alleviating the left ventricle. Next to that, several receptors are present on native AV leaflets, enabling messenger pathways based on their interaction with blood and other shear-stress-related stimuli. Many of these physiological and hemodynamical processes are under-acknowledged but may hold important clues for innovative treatment strategies, or as potential novel targets for therapeutic agents that halt or reverse the process of valve degeneration. A structured overview of these pathways and their implications for cardiothoracic surgeons and cardiologists is lacking. As such, we provide an overview on embryology, hemodynamics, and messenger pathways of the healthy and diseased AV and its implications for clinical practice, by relating this knowledge to current treatment alternatives and clinical decision making.
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Affiliation(s)
- Maximiliaan L Notenboom
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
| | - Lucas Van Hoof
- Department of Cardiac Surgery, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Art Schuermans
- Department of Cardiac Surgery, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Johanna J M Takkenberg
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
| | - Filip R Rega
- Department of Cardiac Surgery, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Yannick J H J Taverne
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
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3
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Crago M, Winlaw DS, Farajikhah S, Dehghani F, Naficy S. Pediatric pulmonary valve replacements: Clinical challenges and emerging technologies. Bioeng Transl Med 2023; 8:e10501. [PMID: 37476058 PMCID: PMC10354783 DOI: 10.1002/btm2.10501] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/17/2023] [Accepted: 01/29/2023] [Indexed: 03/06/2023] Open
Abstract
Congenital heart diseases (CHDs) frequently impact the right ventricular outflow tract, resulting in a significant incidence of pulmonary valve replacement in the pediatric population. While contemporary pediatric pulmonary valve replacements (PPVRs) allow satisfactory patient survival, their biocompatibility and durability remain suboptimal and repeat operations are commonplace, especially for very young patients. This places enormous physical, financial, and psychological burdens on patients and their parents, highlighting an urgent clinical need for better PPVRs. An important reason for the clinical failure of PPVRs is biofouling, which instigates various adverse biological responses such as thrombosis and infection, promoting research into various antifouling chemistries that may find utility in PPVR materials. Another significant contributor is the inevitability of somatic growth in pediatric patients, causing structural discrepancies between the patient and PPVR, stimulating the development of various growth-accommodating heart valve prototypes. This review offers an interdisciplinary perspective on these challenges by exploring clinical experiences, physiological understandings, and bioengineering technologies that may contribute to device development. It thus aims to provide an insight into the design requirements of next-generation PPVRs to advance clinical outcomes and promote patient quality of life.
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Affiliation(s)
- Matthew Crago
- School of Chemical and Biomolecular EngineeringThe University of SydneySydneyAustralia
| | - David S. Winlaw
- Department of Cardiothoracic SurgeryHeart Institute, Cincinnati Children's HospitalCincinnatiOHUSA
| | - Syamak Farajikhah
- School of Chemical and Biomolecular EngineeringThe University of SydneySydneyAustralia
| | - Fariba Dehghani
- School of Chemical and Biomolecular EngineeringThe University of SydneySydneyAustralia
| | - Sina Naficy
- School of Chemical and Biomolecular EngineeringThe University of SydneySydneyAustralia
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4
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Cordoves EM, Vunjak-Novakovic G, Kalfa DM. Designing Biocompatible Tissue Engineered Heart Valves In Situ: JACC Review Topic of the Week. J Am Coll Cardiol 2023; 81:994-1003. [PMID: 36889879 PMCID: PMC10666973 DOI: 10.1016/j.jacc.2022.12.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 12/19/2022] [Indexed: 03/08/2023]
Abstract
Valvular heart disease is a globally prevalent cause of morbidity and mortality, with both congenital and acquired clinical presentations. Tissue engineered heart valves (TEHVs) have the potential to radically shift the treatment landscape for valvular disease by functioning as life-long valve replacements that overcome the current limitations of bioprosthetic and mechanical valves. TEHVs are envisioned to meet these goals by functioning as bioinstructive scaffolds that guide the in situ generation of autologous valves capable of growth, repair, and remodeling within the patient. Despite their promise, clinical translation of in situ TEHVs has proven challenging largely because of the unpredictable and patient-specific nature of the TEHV and host interaction following implantation. In light of this challenge, we propose a framework for the development and clinical translation of biocompatible TEHVs, wherein the native valvular environment actively informs the valve's design parameters and sets the benchmarks by which it is functionally evaluated.
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Affiliation(s)
- Elizabeth M Cordoves
- Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA; Department of Biomedical Engineering, Columbia University, New York, New York, USA
| | - Gordana Vunjak-Novakovic
- Department of Biomedical Engineering, Columbia University, New York, New York, USA; Department of Medicine, Columbia University, New York, New York, USA.
| | - David M Kalfa
- Division of Cardiac, Thoracic and Vascular Surgery, Section of Pediatric and Congenital Cardiac Surgery, New-York Presbyterian-Morgan Stanley Children's Hospital, Columbia University Medical Center, New York, New York, USA.
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5
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Rego BV, Khalighi AH, Gorman JH, Gorman RC, Sacks MS. Simulation of Mitral Valve Plasticity in Response to Myocardial Infarction. Ann Biomed Eng 2023; 51:71-87. [PMID: 36030332 DOI: 10.1007/s10439-022-03043-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 08/01/2022] [Indexed: 01/13/2023]
Abstract
Left ventricular myocardial infarction (MI) has broad and debilitating effects on cardiac function. In many cases, MI leads to ischemic mitral regurgitation (IMR), a condition characterized by incompetency of the mitral valve (MV). IMR has many deleterious effects as well as a high mortality rate. While various clinical treatments for IMR exist, success of these procedures remains limited, in large part because IMR dramatically alters the geometry and function of the MV in ways that are currently not well understood. Previous investigations of post-MI MV remodeling have elucidated that MV tissues have a significant ability to undergo a form of permanent inelastic deformations in the first phase of the post-MI period. These changes appear to be attributable to the altered loading and boundary conditions on the MV itself, as opposed to an independent pathophysiological process. Mechanistically, these results suggest that the MV mostly responds passively to MI during the first 8 weeks post-MI by undergoing a permanent deformation. In the present study, we developed the first computational model of this post-MI MV remodeling process, which we term "mitral valve plasticity." Integrating methodologies and insights from previous studies of in vivo ovine MV function, image-based patient-specific model development, and post-MI MV adaptation, we constructed a representative geometric model of a pre-MI MV. We then performed finite element simulations of the entire MV apparatus under time-dependent boundary conditions and accounting for changes to material properties equivalent to those observed 0-8 weeks post-MI. Our results suggest that during this initial period of adaptation, the MV response to MI can be accurately modeled using a soft tissue plasticity approach, similar to permanent set frameworks that have been applied previously in the context of exogenously crosslinked tissues.
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Affiliation(s)
- Bruno V Rego
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Amir H Khalighi
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, Smilow Center for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, Smilow Center for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael S Sacks
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.
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6
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Teixeira S, Guedes-Martins L. First Trimester Tricuspid Regurgitation: Clinical Significance. Curr Cardiol Rev 2023; 19:e061222211643. [PMID: 36475342 PMCID: PMC10280996 DOI: 10.2174/1573403x19666221206115642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 10/19/2022] [Accepted: 10/31/2022] [Indexed: 12/12/2022] Open
Abstract
Tricuspid regurgitation is a cardiac valvular anomaly that consists of the return of blood to the right atrium during systole due to incomplete valve closure. This structure can be visualized on ultrasound between 11 and 14 weeks of gestation in most cases. Despite being a common finding, even in healthy fetuses, the presence of tricuspid regurgitation may be associated with chromosomal and structural abnormalities. The evaluation of tricuspid flow and the presence of regurgitation on first-trimester ultrasound has shown promising results regarding its role in the early detection of aneuploidies, congenital heart defects, and other adverse perinatal outcomes. This review article aims to demonstrate the importance of tricuspid regurgitation as a secondary marker, and consequently, significant benefits of its early detection when added to the combined first-trimester screening. Its value will be discussed, namely its sensitivity and specificity, alone and together with other current markers in the fetal assessment performed in the first-trimester ultrasound.
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Affiliation(s)
- Sofia Teixeira
- Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto 4050-313, Portugal
- Centro de Medicina Fetal, Medicina Fetal Porto, Serviço de Obstetrícia-Centro Materno Infantil do Norte, Porto 4099-001, Portugal
| | - Luís Guedes-Martins
- Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto 4050-313, Portugal
- Centro de Medicina Fetal, Medicina Fetal Porto, Serviço de Obstetrícia-Centro Materno Infantil do Norte, Porto 4099-001, Portugal
- Departamento da Mulher e da Medicina, Reprodutiva, Centro Hospitalar Universitário do Porto EPE, Centro Materno Infantil do Norte, Largo Prof. Abel Salazar, Porto 4099-001, Portugal
- Unidade de Investigação e Formação-Centro Materno Infantil do Norte, Porto 4099-001, Portugal
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto 4200-319, Portugal
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7
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Vernon MJ, Lu J, Padman B, Lamb C, Kent R, Mela P, Doyle B, Ihdayhid AR, Jansen S, Dilley RJ, De-Juan-Pardo EM. Engineering Heart Valve Interfaces Using Melt Electrowriting: Biomimetic Design Strategies from Multi-Modal Imaging. Adv Healthc Mater 2022; 11:e2201028. [PMID: 36300603 DOI: 10.1002/adhm.202201028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/12/2022] [Indexed: 01/28/2023]
Abstract
Interfaces within biological tissues not only connect different regions but also contribute to the overall functionality of the tissue. This is especially true in the case of the aortic heart valve. Here, melt electrowriting (MEW) is used to engineer complex, user-defined, interfaces for heart valve scaffolds. First, a multi-modal imaging investigation into the interfacial regions of the valve reveals differences in collagen orientation, density, and recruitment in previously unexplored regions including the commissure and inter-leaflet triangle. Overlapping, suturing, and continuous printing methods for interfacing MEW scaffolds are then investigated for their morphological, tensile, and flexural properties, demonstrating the superior performance of continuous interfaces. G-codes for MEW scaffolds with complex interfaces are designed and generated using a novel software and graphical user interface. Finally, a singular MEW scaffold for the interfacial region of the aortic heart valve is presented incorporating continuous interfaces, gradient porosities, variable layer numbers across regions, and tailored fiber orientations inspired by the collagen distribution and orientation from the multi-modal imaging study. The scaffold exhibits similar yield strain, hysteresis, and relaxation behavior to porcine heart valves. This work demonstrates the ability of a bioinspired approach for MEW scaffold design to address the functional complexity of biological tissues.
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Affiliation(s)
- Michael J Vernon
- T3mPLATE, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
| | - Jason Lu
- T3mPLATE, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
| | - Benjamin Padman
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA, 6009, Australia
| | - Christopher Lamb
- T3mPLATE, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
| | - Ross Kent
- Regenerative Medicine Program, CIMA, Universidad de Navarra, Pamplona, Navarra, 31008, Spain
| | - Petra Mela
- Medical Materials and Implants, Department of Mechanical Engineering, Munich Institute of Biomedical Engineering and TUM School of Engineering and Design, Technical University of Munich, Boltzmannstr. 15, 85748, Garching, Germany
| | - Barry Doyle
- Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia.,Australian Research Council Centre for Personalised Therapeutics Technologies, Australian Research Council, Parkville, ACT, 2609, Australia.,British Heart Foundation Centre of Cardiovascular Science, The University of Edinburgh, Edinburgh, EH1-3AT, UK
| | - Abdul Rahman Ihdayhid
- Department of Cardiology, Fiona Stanley Hospital, Perth, WA, 6150, Australia.,Curtin Medical School, Curtin University, Perth, WA, 6102, Australia
| | - Shirley Jansen
- Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,Curtin Medical School, Curtin University, Perth, WA, 6102, Australia.,Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, WA, 6009, Australia.,Heart and Vascular Research Institute, Harry Perkins Institute of Medical Research, Perth, WA, 6009, Australia
| | - Rodney J Dilley
- T3mPLATE, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
| | - Elena M De-Juan-Pardo
- T3mPLATE, Harry Perkins Institute of Medical Research, QEII Medical Centre, and UWA Centre for Medical Research, The University of Western Australia, Perth, WA, 6009, Australia.,School of Engineering, The University of Western Australia, Perth, WA, 6009, Australia
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8
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Liu Y, Wu Z, Chen C, Lu T, Song M, Qi X, Jiang Z, Liu S, Tang Z. The hybrid crosslinking method improved the stability and anti-calcification properties of the bioprosthetic heart valves. Front Bioeng Biotechnol 2022; 10:1008664. [PMID: 36159659 PMCID: PMC9500414 DOI: 10.3389/fbioe.2022.1008664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 08/22/2022] [Indexed: 12/02/2022] Open
Abstract
The bioprosthetic heart valves (BHVs) are the best option for the treatment of valvular heart disease. Glutaraldehyde (Glut) is commonly used as the golden standard reagent for the crosslinking of BHVs. However, the obvious defects of Glut, including residual aldehyde toxicity, degradation and calcification, increase the probability of valve failure in vivo and motivated the exploration of alternatives. Thus, the aim of this study is to develop a non-glutaraldehyde hybrid cross-linking method composed of Neomycin Trisulfate, Polyethylene glycol diglycidyl ether and Tannic acid as a substitute for Glut, which was proven to reduce calcification, degradation, inflammation of the biomaterial. Evaluations of the crosslinked bovine pericardial included histological and ultrastructural characterization, biomechanical performance, biocompatibility and structural stability test, and in vivo anti-inflammation and anti-calcification assay by subcutaneous implantation in juvenile Sprague Dawley rats. The results revealed that the hybrid crosslinked bovine pericardial were superior to Glut crosslinked biomaterial in terms of better hydrophilicity, thermodynamics stability, hemocompatibility and cytocompatibility, higher Young’s Modulus, better stability and resistance to enzymatic hydrolysis, and lower inflammation, degradation and calcification levels in subcutaneous implants. Considering all above performances, it indicates that the hybrid cross-linking method is appropriate to replace Glut as the method for BHV preparation, and particularly this hybrid crosslinked biomaterials may be a promising candidate for next-generation BHVs.
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Affiliation(s)
- Yuhong Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Engineering Laboratory of Human Province for Cardiovascular Biomaterials, Changsha, Hunan, China
| | - Zhongshi Wu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Engineering Laboratory of Human Province for Cardiovascular Biomaterials, Changsha, Hunan, China
| | - Chunyang Chen
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Ting Lu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Mingzhe Song
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Xiaoke Qi
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Zhenlin Jiang
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Sixi Liu
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Engineering Laboratory of Human Province for Cardiovascular Biomaterials, Changsha, Hunan, China
| | - Zhenjie Tang
- Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Engineering Laboratory of Human Province for Cardiovascular Biomaterials, Changsha, Hunan, China
- *Correspondence: Zhenjie Tang,
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9
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Karnibad M, Sharabi M, Lavon K, Morany A, Hamdan A, Haj-Ali R. The effect of the fibrocalcific pathological process on aortic valve stenosis in female patients: a finite element study. Biomed Phys Eng Express 2022; 8. [PMID: 35120335 DOI: 10.1088/2057-1976/ac5223] [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: 11/10/2021] [Accepted: 02/04/2022] [Indexed: 11/11/2022]
Abstract
Calcific aortic valve disease (CAVD) is the most common heart valvular disease in the developed world. Most of the relevant research has been sex-blind, ignoring sex-related biological variables and thus under-appreciate sex differences. However, females present pronounced fibrosis for the same aortic stenosis (AS) severity compared with males, who exhibit more calcification. Herein, we present a computational model of fibrocalcific AV, aiming to investigate its effect on AS development. A parametric study was conducted to explore the influence of the total collagen fiber volume and its architecture on the aortic valve area (AVA). Towards that goal, computational models were generated for three females with stenotic AVs and different volumes of calcium. We have tested the influence of fibrosis on various parameters as fiber architecture, fibrosis location, and transvalvular pressure. We found that increased fiber volume with a low calcium volume could actively contribute to AS and reduce the AVA similarly to high calcium volume. Thus, the computed AVAs for our fibrocalcific models were 0.94 and 0.84 cm2and the clinical (Echo) AVAs were 0.82 and 0.8 cm2. For the heavily calcified model, the computed AVA was 0.8 cm2and the clinical AVA was 0.73 cm2. The proposed models demonstrated how collagen thickening influence the fibrocalcific-AS process in female patients. These models can assist in the clinical decision-making process and treatment development in valve therapy for female patients.
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Affiliation(s)
- Maya Karnibad
- Tel Aviv University, School of Mechanical Engineering, Tel Aviv, 69978, ISRAEL
| | - Mirit Sharabi
- Ariel University, Department of Mechanical engineering and Mechatronics, Ariel, 407000, ISRAEL
| | - Karin Lavon
- Tel Aviv University, School of Mechanical Engineering, Tel Aviv, 69978, ISRAEL
| | - Adi Morany
- Tel Aviv University, School of Mechanical Engineering, Tel Aviv, 69978, ISRAEL
| | - Ashraf Hamdan
- Tel Aviv University, Department of Cardiology, Rabin Medical Center, Tel Aviv, 69978, ISRAEL
| | - Rami Haj-Ali
- Tel Aviv University, School of Mechanical Engineering, Tel Aviv, 69978, ISRAEL
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10
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Rego BV, Pouch AM, Gorman JH, Gorman RC, Sacks MS. Patient-Specific Quantification of Normal and Bicuspid Aortic Valve Leaflet Deformations from Clinically Derived Images. Ann Biomed Eng 2022; 50:1-15. [PMID: 34993699 PMCID: PMC9084616 DOI: 10.1007/s10439-021-02882-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 10/24/2021] [Indexed: 11/24/2022]
Abstract
The clinical benefit of patient-specific modeling of heart valve disease remains an unrealized goal, often a result of our limited understanding of the in vivo milieu. This is particularly true in assessing bicuspid aortic valve (BAV) disease, the most common cardiac congenital defect in humans, which leads to premature and severe aortic stenosis or insufficiency (AS/AI). However, assessment of BAV risk for AS/AI on a patient-specific basis is hampered by the substantial degree of anatomic and functional variations that remain largely unknown. The present study was undertaken to utilize a noninvasive computational pipeline ( https://doi.org/10.1002/cnm.3142 ) that directly yields local heart valve leaflet deformation information using patient-specific real-time three-dimensional echocardiographic imaging (rt-3DE) data. Imaging data was collected for patients with normal tricuspid aortic valve (TAV, [Formula: see text]) and those with BAV ([Formula: see text] with fused left and right coronary leaflets and [Formula: see text] with fused right and non-coronary leaflets), from which the medial surface of each leaflet was extracted. The resulting deformation analysis resulted in, for the first time, quantified differences between the in vivo functional deformations of the TAV and BAV leaflets. Our approach was able to capture the complex, heterogeneous surface deformation fields in both TAV and BAV leaflets. We were able to identify and quantify differences in stretch patterns between leaflet types, and found in particular that stretches experienced by BAV leaflets during closure differ from those of TAV leaflets in terms of both heterogeneity as well as overall magnitude. Deformation is a key parameter in the clinical assessment of valvular function, and serves as a direct means to determine regional variations in structure and function. This study is an essential step toward patient-specific assessment of BAV based on correlating leaflet deformation and AS/AI progression, as it provides a means for assessing patient-specific stretch patterns.
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Affiliation(s)
- Bruno V Rego
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Alison M Pouch
- Gorman Cardiovascular Research Group, Smilow Center for Translational Research, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, Smilow Center for Translational Research, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, Smilow Center for Translational Research, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Michael S Sacks
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA.
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11
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Butany J, Schoen FJ. Cardiac valve replacement and related interventions. Cardiovasc Pathol 2022. [DOI: 10.1016/b978-0-12-822224-9.00010-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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12
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Tandon I, Ozkizilcik A, Ravishankar P, Balachandran K. Aortic valve cell microenvironment: Considerations for developing a valve-on-chip. BIOPHYSICS REVIEWS 2021; 2:041303. [PMID: 38504720 PMCID: PMC10903420 DOI: 10.1063/5.0063608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 11/15/2021] [Indexed: 03/21/2024]
Abstract
Cardiac valves are sophisticated, dynamic structures residing in a complex mechanical and hemodynamic environment. Cardiac valve disease is an active and progressive disease resulting in severe socioeconomic burden, especially in the elderly. Valve disease also leads to a 50% increase in the possibility of associated cardiovascular events. Yet, valve replacement remains the standard of treatment with early detection, mitigation, and alternate therapeutic strategies still lacking. Effective study models are required to further elucidate disease mechanisms and diagnostic and therapeutic strategies. Organ-on-chip models offer a unique and powerful environment that incorporates the ease and reproducibility of in vitro systems along with the complexity and physiological recapitulation of the in vivo system. The key to developing effective valve-on-chip models is maintaining the cell and tissue-level microenvironment relevant to the study application. This review outlines the various components and factors that comprise and/or affect the cell microenvironment that ought to be considered while constructing a valve-on-chip model. This review also dives into the advancements made toward constructing valve-on-chip models with a specific focus on the aortic valve, that is, in vitro studies incorporating three-dimensional co-culture models that incorporate relevant extracellular matrices and mechanical and hemodynamic cues.
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Affiliation(s)
- Ishita Tandon
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Asya Ozkizilcik
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Prashanth Ravishankar
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - Kartik Balachandran
- Department of Biomedical Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
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13
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Deb N, Lacerda CMR. Valvular Endothelial Cell Response to the Mechanical Environment-A Review. Cell Biochem Biophys 2021; 79:695-709. [PMID: 34661855 DOI: 10.1007/s12013-021-01039-z] [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: 05/25/2021] [Accepted: 10/02/2021] [Indexed: 01/08/2023]
Abstract
Heart valve leaflets are complex structures containing valve endothelial cells, interstitial cells, and extracellular matrix. Heart valve endothelial cells sense mechanical stimuli, and communicate amongst themselves and the surrounding cells and extracellular matrix to maintain tissue homeostasis. In the presence of abnormal mechanical stimuli, endothelial cell communication is triggered in defense and such processes may eventually lead to cardiac disease progression. This review focuses on the role of mechanical stimuli on heart valve endothelial surfaces-from heart valve development and maintenance of tissue integrity to disease progression with related signal pathways involved in this process.
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Affiliation(s)
- Nandini Deb
- Jasper Department of Chemical Engineering, The University of Texas at Tyler, 3900 University Blvd, Tyler, 75799, TX, US
| | - Carla M R Lacerda
- Jasper Department of Chemical Engineering, The University of Texas at Tyler, 3900 University Blvd, Tyler, 75799, TX, US.
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14
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Karakaya C, van Asten JGM, Ristori T, Sahlgren CM, Loerakker S. Mechano-regulated cell-cell signaling in the context of cardiovascular tissue engineering. Biomech Model Mechanobiol 2021; 21:5-54. [PMID: 34613528 PMCID: PMC8807458 DOI: 10.1007/s10237-021-01521-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/15/2021] [Indexed: 01/18/2023]
Abstract
Cardiovascular tissue engineering (CVTE) aims to create living tissues, with the ability to grow and remodel, as replacements for diseased blood vessels and heart valves. Despite promising results, the (long-term) functionality of these engineered tissues still needs improvement to reach broad clinical application. The functionality of native tissues is ensured by their specific mechanical properties directly arising from tissue organization. We therefore hypothesize that establishing a native-like tissue organization is vital to overcome the limitations of current CVTE approaches. To achieve this aim, a better understanding of the growth and remodeling (G&R) mechanisms of cardiovascular tissues is necessary. Cells are the main mediators of tissue G&R, and their behavior is strongly influenced by both mechanical stimuli and cell-cell signaling. An increasing number of signaling pathways has also been identified as mechanosensitive. As such, they may have a key underlying role in regulating the G&R of tissues in response to mechanical stimuli. A more detailed understanding of mechano-regulated cell-cell signaling may thus be crucial to advance CVTE, as it could inspire new methods to control tissue G&R and improve the organization and functionality of engineered tissues, thereby accelerating clinical translation. In this review, we discuss the organization and biomechanics of native cardiovascular tissues; recent CVTE studies emphasizing the obtained engineered tissue organization; and the interplay between mechanical stimuli, cell behavior, and cell-cell signaling. In addition, we review past contributions of computational models in understanding and predicting mechano-regulated tissue G&R and cell-cell signaling to highlight their potential role in future CVTE strategies.
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Affiliation(s)
- Cansu Karakaya
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Jordy G M van Asten
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Tommaso Ristori
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands.,Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Cecilia M Sahlgren
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands.,Faculty of Science and Engineering, Biosciences, Åbo Akademi, Turku, Finland
| | - Sandra Loerakker
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands. .,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands.
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15
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Celikkin N, Presutti D, Maiullari F, Fornetti E, Agarwal T, Paradiso A, Volpi M, Święszkowski W, Bearzi C, Barbetta A, Zhang YS, Gargioli C, Rizzi R, Costantini M. Tackling Current Biomedical Challenges With Frontier Biofabrication and Organ-On-A-Chip Technologies. Front Bioeng Biotechnol 2021; 9:732130. [PMID: 34604190 PMCID: PMC8481890 DOI: 10.3389/fbioe.2021.732130] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/31/2021] [Indexed: 12/13/2022] Open
Abstract
In the last decades, biomedical research has significantly boomed in the academia and industrial sectors, and it is expected to continue to grow at a rapid pace in the future. An in-depth analysis of such growth is not trivial, given the intrinsic multidisciplinary nature of biomedical research. Nevertheless, technological advances are among the main factors which have enabled such progress. In this review, we discuss the contribution of two state-of-the-art technologies-namely biofabrication and organ-on-a-chip-in a selection of biomedical research areas. We start by providing an overview of these technologies and their capacities in fabricating advanced in vitro tissue/organ models. We then analyze their impact on addressing a range of current biomedical challenges. Ultimately, we speculate about their future developments by integrating these technologies with other cutting-edge research fields such as artificial intelligence and big data analysis.
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Affiliation(s)
- Nehar Celikkin
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Dario Presutti
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Fabio Maiullari
- Istituto Nazionale Genetica Molecolare INGM “Romeo Ed Enrica Invernizzi”, Milan, Italy
| | | | - Tarun Agarwal
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Alessia Paradiso
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw, Poland
| | - Marina Volpi
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw, Poland
| | - Wojciech Święszkowski
- Faculty of Materials Science and Engineering, Warsaw University of Technology, Warsaw, Poland
| | - Claudia Bearzi
- Istituto Nazionale Genetica Molecolare INGM “Romeo Ed Enrica Invernizzi”, Milan, Italy
- Institute of Genetic and Biomedical Research, National Research Council of Italy (IRGB-CNR), Milan, Italy
| | - Andrea Barbetta
- Department of Chemistry, Sapienza University of Rome, Rome, Italy
| | - Yu Shrike Zhang
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Cambridge, MA, United States
| | - Cesare Gargioli
- Department of Biology, Rome University Tor Vergata, Rome, Italy
| | - Roberto Rizzi
- Istituto Nazionale Genetica Molecolare INGM “Romeo Ed Enrica Invernizzi”, Milan, Italy
- Institute of Genetic and Biomedical Research, National Research Council of Italy (IRGB-CNR), Milan, Italy
- Institute of Biomedical Technologies, National Research Council of Italy (ITB-CNR), Milan, Italy
| | - Marco Costantini
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
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16
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Ambari AM, Setianto B, Santoso A, Radi B, Dwiputra B, Susilowati E, Tulrahmi F, Wind A, Cramer MJM, Doevendans P. Randomised controlled trial into the role of ramipril in fibrosis reduction in rheumatic heart disease: the RamiRHeD trial protocol. BMJ Open 2021; 11:e048016. [PMID: 34518254 PMCID: PMC8438922 DOI: 10.1136/bmjopen-2020-048016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Rheumatic heart disease (RHD) is a major burden in developing countries and accounts for 80% of all people living with the disease, where it causes most cardiovascular morbidity and mortality in children and young adults. Chronic inflammation and fibrosis of heart valve tissue due to chronic inflammation in RHD will cause calcification and thickening of the impacted heart valves, especially the mitral valve. This fibrogenesis is enhanced by the production of angiotensin II by increased transforming growth factor β expression and later by the binding of interleukin-33, which is known to have antihypertrophic and antifibrotic effects, to soluble sST2. sST2 binding to this non-natural ligand worsens fibrosis. Therefore, we hypothesise that ACE inhibitors (ACEIs) would improve rheumatic mitral valve stenosis. METHODS AND ANALYSIS This is a single-centre, double-blind, placebo-controlled, randomised clinical trial with a pre-post test design. Patients with rheumatic mitral stenosis and valve dysfunction will be planned for cardiac valve replacement operation and will be given ramipril 5 mg or placebo for a minimum of 12 weeks before the surgery. The expression of ST2 in the mitral valve is considered to be representative of cardiac fibrosis. Mitral valve tissue will be stained by immunohistochemistry to ST2. Plasma ST2 will be measured by ELISA. This study is conducted in the Department of Cardiology and Vascular Medicine, Universitas Indonesia, National Cardiac Center Harapan Kita Hospital, Jakarta, Indonesia, starting on 27 June 2019. ETHICS AND DISSEMINATION The performance and dissemination of this study were approved by the ethics committee of National Cardiovascular Center Harapan Kita with ethical code LB.02.01/VII/286/KEP.009/2018. TRIAL REGISTRATION NUMBER NCT03991910.
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Affiliation(s)
- Ade Meidian Ambari
- Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia, West Jakarta, Jakarta, Indonesia
| | - Budhi Setianto
- Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia, West Jakarta, Jakarta, Indonesia
| | - Anwar Santoso
- Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia, West Jakarta, Jakarta, Indonesia
| | - Basuni Radi
- Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia, West Jakarta, Jakarta, Indonesia
| | - Bambang Dwiputra
- Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
- Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Indonesia, West Jakarta, Jakarta, Indonesia
| | - Eliana Susilowati
- Research Assistant of Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
| | - Fadilla Tulrahmi
- Research Assistant of Department of Cardiovascular Prevention and Rehabilitation, National Cardiovascular Center Harapan Kita, West Jakarta, Jakarta, Indonesia
| | - Annemiek Wind
- Department of Cardiology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | | | - Pieter Doevendans
- Department of Cardiology, University Medical Centre Utrecht, Utrecht, The Netherlands
- Central Military Hospital, Netherlands Heart Institute, Utrecht, The Netherlands
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17
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Williams DF, Bezuidenhout D, de Villiers J, Human P, Zilla P. Long-Term Stability and Biocompatibility of Pericardial Bioprosthetic Heart Valves. Front Cardiovasc Med 2021; 8:728577. [PMID: 34589529 PMCID: PMC8473620 DOI: 10.3389/fcvm.2021.728577] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/19/2021] [Indexed: 01/15/2023] Open
Abstract
The use of bioprostheses for heart valve therapy has gradually evolved over several decades and both surgical and transcatheter devices are now highly successful. The rapid expansion of the transcatheter concept has clearly placed a significant onus on the need for improved production methods, particularly the pre-treatment of bovine pericardium. Two of the difficulties associated with the biocompatibility of bioprosthetic valves are the possibilities of immune responses and calcification, which have led to either catastrophic failure or slow dystrophic changes. These have been addressed by evolutionary trends in cross-linking and decellularization techniques and, over the last two decades, the improvements have resulted in somewhat greater durability. However, as the need to consider the use of bioprosthetic valves in younger patients has become an important clinical and sociological issue, the requirement for even greater longevity and safety is now paramount. This is especially true with respect to potential therapies for young people who are afflicted by rheumatic heart disease, mostly in low- to middle-income countries, for whom no clinically acceptable and cost-effective treatments currently exist. To extend longevity to this new level, it has been necessary to evaluate the mechanisms of pericardium biocompatibility, with special emphasis on the interplay between cross-linking, decellularization and anti-immunogenicity processes. These mechanisms are reviewed in this paper. On the basis of a better understanding of these mechanisms, a few alternative treatment protocols have been developed in the last few years. The most promising protocol here is based on a carefully designed combination of phases of tissue-protective decellularization with a finely-titrated cross-linking sequence. Such refined protocols offer considerable potential in the progress toward superior longevity of pericardial heart valves and introduce a scientific dimension beyond the largely disappointing 'anti-calcification' treatments of past decades.
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Affiliation(s)
- David F. Williams
- Strait Access Technologies Ltd. Pty., Cape Town, South Africa
- Wake Forest Institute of Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Deon Bezuidenhout
- Strait Access Technologies Ltd. Pty., Cape Town, South Africa
- Cardiovascular Research Unit, Cape Heart Institute, University of Cape Town, Cape Town, South Africa
| | | | - Paul Human
- Christiaan Barnard Department of Cardiothoracic Surgery, University of Cape Town, Cape Town, South Africa
| | - Peter Zilla
- Strait Access Technologies Ltd. Pty., Cape Town, South Africa
- Cardiovascular Research Unit, Cape Heart Institute, University of Cape Town, Cape Town, South Africa
- Christiaan Barnard Department of Cardiothoracic Surgery, University of Cape Town, Cape Town, South Africa
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18
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Park MH, Zhu Y, Imbrie-Moore AM, Wang H, Marin-Cuartas M, Paulsen MJ, Woo YJ. Heart Valve Biomechanics: The Frontiers of Modeling Modalities and the Expansive Capabilities of Ex Vivo Heart Simulation. Front Cardiovasc Med 2021; 8:673689. [PMID: 34307492 PMCID: PMC8295480 DOI: 10.3389/fcvm.2021.673689] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 05/17/2021] [Indexed: 01/05/2023] Open
Abstract
The field of heart valve biomechanics is a rapidly expanding, highly clinically relevant area of research. While most valvular pathologies are rooted in biomechanical changes, the technologies for studying these pathologies and identifying treatments have largely been limited. Nonetheless, significant advancements are underway to better understand the biomechanics of heart valves, pathologies, and interventional therapeutics, and these advancements have largely been driven by crucial in silico, ex vivo, and in vivo modeling technologies. These modalities represent cutting-edge abilities for generating novel insights regarding native, disease, and repair physiologies, and each has unique advantages and limitations for advancing study in this field. In particular, novel ex vivo modeling technologies represent an especially promising class of translatable research that leverages the advantages from both in silico and in vivo modeling to provide deep quantitative and qualitative insights on valvular biomechanics. The frontiers of this work are being discovered by innovative research groups that have used creative, interdisciplinary approaches toward recapitulating in vivo physiology, changing the landscape of clinical understanding and practice for cardiovascular surgery and medicine.
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Affiliation(s)
- Matthew H Park
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States.,Department of Mechanical Engineering, Stanford University, Stanford, CA, United States
| | - Yuanjia Zhu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States.,Department of Bioengineering, Stanford University, Stanford, CA, United States
| | - Annabel M Imbrie-Moore
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States.,Department of Mechanical Engineering, Stanford University, Stanford, CA, United States
| | - Hanjay Wang
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States
| | - Mateo Marin-Cuartas
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States.,University Department of Cardiac Surgery, Leipzig Heart Center, Leipzig, Germany
| | - Michael J Paulsen
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States
| | - Y Joseph Woo
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, United States.,Department of Bioengineering, Stanford University, Stanford, CA, United States
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19
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Abstract
Calcific aortic valve disease sits at the confluence of multiple world-wide epidemics of aging, obesity, diabetes, and renal dysfunction, and its prevalence is expected to nearly triple over the next 3 decades. This is of particularly dire clinical relevance, as calcific aortic valve disease can progress rapidly to aortic stenosis, heart failure, and eventually premature death. Unlike in atherosclerosis, and despite the heavy clinical toll, to date, no pharmacotherapy has proven effective to halt calcific aortic valve disease progression, with invasive and costly aortic valve replacement representing the only treatment option currently available. This substantial gap in care is largely because of our still-limited understanding of both normal aortic valve biology and the key regulatory mechanisms that drive disease initiation and progression. Drug discovery is further hampered by the inherent intricacy of the valvular microenvironment: a unique anatomic structure, a complex mixture of dynamic biomechanical forces, and diverse and multipotent cell populations collectively contributing to this currently intractable problem. One promising and rapidly evolving tactic is the application of multiomics approaches to fully define disease pathogenesis. Herein, we summarize the application of (epi)genomics, transcriptomics, proteomics, and metabolomics to the study of valvular heart disease. We also discuss recent forays toward the omics-based characterization of valvular (patho)biology at single-cell resolution; these efforts promise to shed new light on cellular heterogeneity in healthy and diseased valvular tissues and represent the potential to efficaciously target and treat key cell subpopulations. Last, we discuss systems biology- and network medicine-based strategies to extract meaning, mechanisms, and prioritized drug targets from multiomics datasets.
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Affiliation(s)
- Mark C. Blaser
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Simon Kraler
- Center for Molecular Cardiology, University of Zurich, Schlieren, CH
| | - Thomas F. Lüscher
- Center for Molecular Cardiology, University of Zurich, Schlieren, CH
- Heart Division, Royal Brompton & Harefield Hospitals, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Elena Aikawa
- Center for Interdisciplinary Cardiovascular Sciences, Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Center for Excellence in Vascular Biology, Cardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
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20
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Biology and Biomechanics of the Heart Valve Extracellular Matrix. J Cardiovasc Dev Dis 2020; 7:jcdd7040057. [PMID: 33339213 PMCID: PMC7765611 DOI: 10.3390/jcdd7040057] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/02/2020] [Accepted: 12/13/2020] [Indexed: 02/06/2023] Open
Abstract
Heart valves are dynamic structures that, in the average human, open and close over 100,000 times per day, and 3 × 109 times per lifetime to maintain unidirectional blood flow. Efficient, coordinated movement of the valve structures during the cardiac cycle is mediated by the intricate and sophisticated network of extracellular matrix (ECM) components that provide the necessary biomechanical properties to meet these mechanical demands. Organized in layers that accommodate passive functional movements of the valve leaflets, heart valve ECM is synthesized during embryonic development, and remodeled and maintained by resident cells throughout life. The failure of ECM organization compromises biomechanical function, and may lead to obstruction or leaking, which if left untreated can lead to heart failure. At present, effective treatment for heart valve dysfunction is limited and frequently ends with surgical repair or replacement, which comes with insuperable complications for many high-risk patients including aged and pediatric populations. Therefore, there is a critical need to fully appreciate the pathobiology of biomechanical valve failure in order to develop better, alternative therapies. To date, the majority of studies have focused on delineating valve disease mechanisms at the cellular level, namely the interstitial and endothelial lineages. However, less focus has been on the ECM, shown previously in other systems, to be a promising mechanism-inspired therapeutic target. Here, we highlight and review the biology and biomechanical contributions of key components of the heart valve ECM. Furthermore, we discuss how human diseases, including connective tissue disorders lead to aberrations in the abundance, organization and quality of these matrix proteins, resulting in instability of the valve infrastructure and gross functional impairment.
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21
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Meador WD, Mathur M, Sugerman GP, Malinowski M, Jazwiec T, Wang X, Lacerda CM, Timek TA, Rausch MK. The tricuspid valve also maladapts as shown in sheep with biventricular heart failure. eLife 2020; 9:63855. [PMID: 33320094 PMCID: PMC7738185 DOI: 10.7554/elife.63855] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/02/2020] [Indexed: 11/28/2022] Open
Abstract
Over 1.6 million Americans suffer from significant tricuspid valve leakage. In most cases this leakage is designated as secondary. Thus, valve dysfunction is assumed to be due to valve-extrinsic factors. We challenge this paradigm and hypothesize that the tricuspid valve maladapts in those patients rendering the valve at least partially culpable for its dysfunction. As a first step in testing this hypothesis, we set out to demonstrate that the tricuspid valve maladapts in disease. To this end, we induced biventricular heart failure in sheep that developed tricuspid valve leakage. In the anterior leaflets of those animals, we investigated maladaptation on multiple scales. We demonstrated alterations on the protein and cell-level, leading to tissue growth, thickening, and stiffening. These data provide a new perspective on a poorly understood, yet highly prevalent disease. Our findings may motivate novel therapy options for many currently untreated patients with leaky tricuspid valves.
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Affiliation(s)
- William D Meador
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, United States
| | - Mrudang Mathur
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, United States
| | - Gabriella P Sugerman
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, United States
| | - Marcin Malinowski
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, United States.,Department of Cardiac Surgery, Medical University of Silesia, School of Medicine in Katowice, Katowice, Poland
| | - Tomasz Jazwiec
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, United States.,Department of Cardiac, Vascular and Endovascular Surgery and Transplantology, Medical University of Silesia in Katowice, Silesian Centre for Heart Diseases, Zabrze, Poland
| | - Xinmei Wang
- Department of Chemical Engineering, Texas Tech University, Lubbock, United States
| | - Carla Mr Lacerda
- Department of Chemical Engineering, Texas Tech University, Lubbock, United States
| | - Tomasz A Timek
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, United States
| | - Manuel K Rausch
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, United States.,Department of Mechanical Engineering, The University of Texas at Austin, Austin, United States.,Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, United States
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22
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Mathur M, Meador WD, Jazwiec T, Malinowski M, Timek TA, Rausch MK. Tricuspid Valve Annuloplasty Alters Leaflet Mechanics. Ann Biomed Eng 2020; 48:2911-2923. [PMID: 32761558 PMCID: PMC8000450 DOI: 10.1007/s10439-020-02586-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 07/27/2020] [Indexed: 10/23/2022]
Abstract
Tricuspid valve regurgitation is associated with significant morbidity and mortality. Its most common treatment option, tricuspid valve annuloplasty, is not optimally effective in the long-term. Toward identifying the causes for annuloplasty's ineffectiveness, we have previously investigated the technique's impact on the tricuspid annulus and the right ventricular epicardium. In our current work, we are extending our analysis to the anterior tricuspid valve leaflet. To this end, we adopted our previous strategy of performing DeVega suture annuloplasty as an experimental methodology that allows us to externally control the degree of cinching during annuloplasty. Thus, in ten sheep we successively cinched the annulus and quantified changes to leaflet motion, dynamics, and strain in the beating heart by combining sonomicrometry with our well-established mechanical framework. We found that successive cinching of the valve enforced earlier coaptation and thus reduced leaflet range of motion. Additionally, leaflet angular velocity during opening and closing decreased. Finally, we found that leaflet strains were also reduced. Specifically, radial and areal strains decreased as a function of annular cinching. Our findings are critical as they suggest that suture annuloplasty alters the mechanics of the tricuspid valve leaflets which may disrupt their resident cells' mechanobiological equilibrium. Long-term, such disruption may stimulate tissue maladaptation which could contribute to annuloplasty's sub-optimal effectiveness. Additionally, our data suggest that the extent to which annuloplasty alters leaflet mechanics can be controlled via degree of cinching. Hence, our data may provide direct surgical guidelines.
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Affiliation(s)
- Mrudang Mathur
- Department of Mechanical Engineering, University of Texas at Austin, 204 E Dean Keeton Street, Austin, TX, 78712, USA
| | - William D Meador
- Department of Biomedical Engineering, University of Texas at Austin, 107 W Dean Keeton Street, Austin, TX, 78712, USA
| | - Tomasz Jazwiec
- Department of Cardiac, Vascular and Endovascular Surgery and Transplantology, Silesian Centre for Heart Diseases, Medical University of Silesia in Katowice, Zabrze, Poland
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI, 49503, USA
| | - Marcin Malinowski
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI, 49503, USA
- Department of Cardiac Surgery, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Tomasz A Timek
- Division of Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI, 49503, USA
| | - Manuel K Rausch
- Departments of Aerospace Engineering & Engineering Mechanics, Biomedical Engineering, University of Texas at Austin, 2617 Wichita Street, Austin, TX, 78712, USA.
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23
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Uiterwijk M, Smits AIPM, van Geemen D, van Klarenbosch B, Dekker S, Cramer MJ, van Rijswijk JW, Lurier EB, Di Luca A, Brugmans MCP, Mes T, Bosman AW, Aikawa E, Gründeman PF, Bouten CVC, Kluin J. In Situ Remodeling Overrules Bioinspired Scaffold Architecture of Supramolecular Elastomeric Tissue-Engineered Heart Valves. ACTA ACUST UNITED AC 2020; 5:1187-1206. [PMID: 33426376 PMCID: PMC7775962 DOI: 10.1016/j.jacbts.2020.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 09/22/2020] [Accepted: 09/22/2020] [Indexed: 11/17/2022]
Abstract
In situ tissue engineering that uses resorbable synthetic heart valve scaffolds is an affordable and practical approach for heart valve replacement; therefore, it is attractive for clinical use. This study showed no consistent collagen organization in the predefined direction of electrospun scaffolds made from a resorbable supramolecular elastomer with random or circumferentially aligned fibers, after 12 months of implantation in sheep. These unexpected findings and the observed intervalvular variability highlight the need for a mechanistic understanding of the long-term in situ remodeling processes in large animal models to improve predictability of outcome toward robust and safe clinical application.
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Affiliation(s)
- Marcelle Uiterwijk
- Department of Cardiothoracic Surgery, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Anthal I P M Smits
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Daphne van Geemen
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Bas van Klarenbosch
- Department of Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Sylvia Dekker
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Maarten Jan Cramer
- Department of Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jan Willem van Rijswijk
- Department of Cardiothoracic Surgery, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Emily B Lurier
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, Pennsylvania, USA
| | - Andrea Di Luca
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | | | | | | | - Elena Aikawa
- Center for Excellence in Vascular Biology, Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Paul F Gründeman
- Department of Cardiothoracic Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Carlijn V C Bouten
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Jolanda Kluin
- Department of Cardiothoracic Surgery, Amsterdam University Medical Center, Amsterdam, the Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
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24
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Bajpai A, Li R, Chen W. The cellular mechanobiology of aging: from biology to mechanics. Ann N Y Acad Sci 2020; 1491:3-24. [PMID: 33231326 DOI: 10.1111/nyas.14529] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 10/10/2020] [Accepted: 10/21/2020] [Indexed: 12/14/2022]
Abstract
Aging is a chronic, complicated process that leads to degenerative physical and biological changes in living organisms. Aging is associated with permanent, gradual physiological cellular decay that affects all aspects of cellular mechanobiological features, including cellular cytoskeleton structures, mechanosensitive signaling pathways, and forces in the cell, as well as the cell's ability to sense and adapt to extracellular biomechanical signals in the tissue environment through mechanotransduction. These mechanobiological changes in cells are directly or indirectly responsible for dysfunctions and diseases in various organ systems, including the cardiovascular, musculoskeletal, skin, and immune systems. This review critically examines the role of aging in the progressive decline of the mechanobiology occurring in cells, and establishes mechanistic frameworks to understand the mechanobiological effects of aging on disease progression and to develop new strategies for halting and reversing the aging process. Our review also highlights the recent development of novel bioengineering approaches for studying the key mechanobiological mechanisms in aging.
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Affiliation(s)
- Apratim Bajpai
- Department of Mechanical and Aerospace Engineering, Tandon School of Engineering, New York University, Brooklyn, New York
| | - Rui Li
- Department of Mechanical and Aerospace Engineering, Tandon School of Engineering, New York University, Brooklyn, New York.,Department of Biomedical Engineering, Tandon School of Engineering, New York University, Brooklyn, New York
| | - Weiqiang Chen
- Department of Mechanical and Aerospace Engineering, Tandon School of Engineering, New York University, Brooklyn, New York.,Department of Biomedical Engineering, Tandon School of Engineering, New York University, Brooklyn, New York.,Laura and Isaac Perlmutter Cancer Center, NYU Langone Health, New York, New York
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25
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Motta SE, Fioretta ES, Lintas V, Dijkman PE, Hilbe M, Frese L, Cesarovic N, Loerakker S, Baaijens FPT, Falk V, Hoerstrup SP, Emmert MY. Geometry influences inflammatory host cell response and remodeling in tissue-engineered heart valves in-vivo. Sci Rep 2020; 10:19882. [PMID: 33199702 PMCID: PMC7669851 DOI: 10.1038/s41598-020-76322-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 10/15/2020] [Indexed: 12/14/2022] Open
Abstract
Regenerative tissue-engineered matrix-based heart valves (TEM-based TEHVs) may become an alternative to currently-used bioprostheses for transcatheter valve replacement. We recently identified TEM-based TEHVs-geometry as one key-factor guiding their remodeling towards successful long-term performance or failure. While our first-generation TEHVs, with a simple, non-physiological valve-geometry, failed over time due to leaflet-wall fusion phenomena, our second-generation TEHVs, with a computational modeling-inspired design, showed native-like remodeling resulting in long-term performance. However, a thorough understanding on how TEHV-geometry impacts the underlying host cell response, which in return determines tissue remodeling, is not yet fully understood. To assess that, we here present a comparative samples evaluation derived from our first- and second-generation TEHVs. We performed an in-depth qualitative and quantitative (immuno-)histological analysis focusing on key-players of the inflammatory and remodeling cascades (M1/M2 macrophages, α-SMA+- and endothelial cells). First-generation TEHVs were prone to chronic inflammation, showing a high presence of macrophages and α-SMA+-cells, hinge-area thickening, and delayed endothelialization. Second-generation TEHVs presented with negligible amounts of macrophages and α-SMA+-cells, absence of hinge-area thickening, and early endothelialization. Our results suggest that TEHV-geometry can significantly influence the host cell response by determining the infiltration and presence of macrophages and α-SMA+-cells, which play a crucial role in orchestrating TEHV remodeling.
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Affiliation(s)
- Sarah E Motta
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland.,Wyss Translational Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Emanuela S Fioretta
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Valentina Lintas
- Wyss Translational Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Petra E Dijkman
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Monika Hilbe
- Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Laura Frese
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Nikola Cesarovic
- Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany.,Department of Health Sciences and Technology, Swiss Federal Institute of Technology, Zurich, Switzerland
| | - Sandra Loerakker
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.,Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Frank P T Baaijens
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Volkmar Falk
- Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany.,Department of Health Sciences and Technology, Swiss Federal Institute of Technology, Zurich, Switzerland.,Department of Cardiovascular Surgery, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Simon P Hoerstrup
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland.,Wyss Translational Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Maximilian Y Emmert
- Institute for Regenerative Medicine (IREM), University of Zurich, Wagistrasse 12, 8952, Schlieren, Switzerland. .,Wyss Translational Center Zurich, University and ETH Zurich, Zurich, Switzerland. .,Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany. .,Department of Cardiovascular Surgery, Charité Universitätsmedizin Berlin, Berlin, Germany.
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26
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Ayoub S, Howsmon DP, Lee CH, Sacks MS. On the role of predicted in vivo mitral valve interstitial cell deformation on its biosynthetic behavior. Biomech Model Mechanobiol 2020; 20:135-144. [PMID: 32761471 DOI: 10.1007/s10237-020-01373-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/28/2020] [Indexed: 02/06/2023]
Abstract
Ischemic mitral regurgitation (IMR), a frequent complication of myocardial infarction, is characterized by regurgitation of blood from the left ventricle back into the left atrium. Physical interventions via surgery or less-invasive techniques are the only available therapies for IMR, with valve repair via undersized ring annuloplasty (URA) generally preferred over valve replacement. However, recurrence of IMR after URA occurs frequently and is attributed to continued remodeling of the MV and infarct region of the left ventricle. The mitral valve interstitial cells (MVICs) that maintain the tissue integrity of the MV leaflets are highly mechanosensitive, and altered loading post-URA is thought to lead to aberrant MVIC-directed tissue remodeling. Although studies have investigated aspects of mechanically directed VIC activation and remodeling potential, there remains a substantial disconnect between organ-level biomechanics and cell-level phenomena. Herein, we utilized an extant multiscale computational model of the MV that linked MVIC to organ-level MV biomechanical behaviors to simulate changes in MVIC deformation following URA. A planar biaxial bioreactor system was then used to cyclically stretch explanted MV leaflet tissue, emulating the in vivo changes in loading following URA. This simulation-directed experimental investigation revealed that post-URA deformations resulted in decreased MVIC activation and collagen mass fraction. These results are consistent with the hypothesis that URA failures post-IMR are due, in part, to reduced MVIC-mediated maintenance of the MV leaflet tissue resulting from a reduction in physical stimuli required for leaflet tissue homeostasis. Such information can inform the development of novel URA strategies with improved durability.
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Affiliation(s)
- Salma Ayoub
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, USA
| | - Daniel P Howsmon
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, USA
| | - Chung-Hao Lee
- School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, OK, 73019, USA
| | - Michael S Sacks
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, USA.
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27
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Meador WD, Mathur M, Sugerman GP, Jazwiec T, Malinowski M, Bersi MR, Timek TA, Rausch MK. A detailed mechanical and microstructural analysis of ovine tricuspid valve leaflets. Acta Biomater 2020; 102:100-113. [PMID: 31760220 DOI: 10.1016/j.actbio.2019.11.039] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/14/2019] [Accepted: 11/19/2019] [Indexed: 12/26/2022]
Abstract
The tricuspid valve ensures unidirectional blood flow from the right atrium to the right ventricle. The three tricuspid leaflets operate within a dynamic stress environment of shear, bending, tensile, and compressive forces, which is cyclically repeated nearly three billion times in a lifetime. Ostensibly, the microstructural and mechanical properties of the tricuspid leaflets have mechanobiologically evolved to optimally support their function under those forces. Yet, how the tricuspid leaflet microstructure determines its mechanical properties and whether this relationship differs between the three leaflets is unknown. Here we perform a microstructural and mechanical analysis in matched ovine tricuspid leaflet samples. We found that the microstructure and mechanical properties vary among the three tricuspid leaflets in sheep. Specifically, we found that tricuspid leaflet composition, collagen orientation, and valve cell nuclear morphology are spatially heterogeneous and vary across leaflet type. Furthermore, under biaxial tension, the leaflets' mechanical behaviors exhibited unequal degrees of mechanical anisotropy. Most importantly, we found that the septal leaflet was stiffer in the radial direction and not the circumferential direction as with the other two leaflets. The differences we observed in leaflet microstructure coincide with the varying biaxial mechanics among leaflets. Our results demonstrate the structure-function relationship for each leaflet in the tricuspid valve. We anticipate our results to be vital toward developing more accurate, leaflet-specific tricuspid valve computational models. Furthermore, our results may be clinically important, informing differential surgical treatments of the tricuspid valve leaflets. Finally, the identified structure-function relationships may provide insight into the homeostatic and remodeling potential of valvular cells in altered mechanical environments, such as in diseased or repaired tricuspid valves. STATEMENT OF SIGNIFICANCE: Our work is significant as we investigated the structure-function relationship of ovine tricuspid valve leaflets. This is important as tricuspid valves fail frequently and our current approach to repairing them is suboptimal. Specifically, we related the distribution of structural and cellular elements, such as collagen, glycosaminoglycans, and cell nuclei, to each leaflet's mechanical properties. We found that leaflets have different structures and that their mechanics differ. This may, in the future, inform leaflet-specific treatment strategies and help optimize surgical outcomes.
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Affiliation(s)
- William D Meador
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78705, USA
| | - Mrudang Mathur
- Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78705, USA
| | - Gabriella P Sugerman
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78705, USA
| | - Tomasz Jazwiec
- Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI 49503, USA; Department of Cardiac, Vascular, and Endovascular Surgery and Transplantology, Medical University of Silesia School of Medicine in Katowice, Silesian Centre for Heart Diseases, Zabrze, Poland
| | - Marcin Malinowski
- Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI 49503, USA; Department of Cardiac Surgery, Medical University of Silesia School of Medicine in Katowice, Katowice, Poland
| | - Matthew R Bersi
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37235, USA
| | - Tomasz A Timek
- Cardiothoracic Surgery, Spectrum Health, Grand Rapids, MI 49503, USA
| | - Manuel K Rausch
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78705, USA; Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78705, USA; Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, TX 78705, USA.
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28
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Oyama MA, Elliott C, Loughran KA, Kossar AP, Castillero E, Levy RJ, Ferrari G. Comparative pathology of human and canine myxomatous mitral valve degeneration: 5HT and TGF-β mechanisms. Cardiovasc Pathol 2020; 46:107196. [PMID: 32006823 DOI: 10.1016/j.carpath.2019.107196] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/16/2019] [Accepted: 12/28/2019] [Indexed: 12/25/2022] Open
Abstract
Myxomatous mitral valve degeneration (MMVD) is a leading cause of valve repair or replacement secondary to the production of mitral regurgitation, cardiac enlargement, systolic dysfunction, and heart failure. The pathophysiology of myxomatous mitral valve degeneration is complex and incompletely understood, but key features include activation and transformation of mitral valve (MV) valvular interstitial cells (VICs) into an active phenotype leading to remodeling of the extracellular matrix and compromise of the structural components of the mitral valve leaflets. Uncovering the mechanisms behind these events offers the potential for therapies to prevent, delay, or reverse myxomatous mitral valve degeneration. One such mechanism involves the neurotransmitter serotonin (5HT), which has been linked to development of valvulopathy in a variety of settings, including valvulopathy induced by serotonergic drugs, Serotonin-producing carcinoid tumors, and development of valvulopathy in laboratory animals exposed to high levels of serotonin. Similar to humans, the domestic dog also experiences naturally occurring myxomatous mitral valve degeneration, and in some breeds of dogs, the lifetime prevalence of myxomatous mitral valve degeneration reaches 100%. In dogs, myxomatous mitral valve degeneration has been associated with high serum serotonin, increased expression of serotonin-receptors, autocrine production of serotonin within the mitral valve leaflets, and downregulation of serotonin clearance mechanisms. One pathway closely associated with serotonin involves transforming growth factor beta (TGF-β) and the two pathways share a common ability to activate mitral valve valvular interstitial cells in both humans and dogs. Understanding the role of serotonin and transforming growth factor beta in myxomatous mitral valve degeneration gives rise to potential therapies, such as 5HT receptor (5HT-R) antagonists. The main purposes of this review are to highlight the commonalities between myxomatous mitral valve degeneration in humans and dogs, with specific regards to serotonin and transforming growth factor beta, and to champion the dog as a relevant and particularly valuable model of human disease that can accelerate development of novel therapies.
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Affiliation(s)
- Mark A Oyama
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA; Institute for Translational Medicine and Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Chad Elliott
- Department of Surgery, Columbia Cardiovascular Institute and College of Physicians and Surgeons at Columbia University, New York, NY, USA
| | - Kerry A Loughran
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexander P Kossar
- Department of Surgery, Columbia Cardiovascular Institute and College of Physicians and Surgeons at Columbia University, New York, NY, USA
| | - Estibaliz Castillero
- Department of Surgery, Columbia Cardiovascular Institute and College of Physicians and Surgeons at Columbia University, New York, NY, USA
| | - Robert J Levy
- The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Giovanni Ferrari
- Department of Surgery, Columbia Cardiovascular Institute and College of Physicians and Surgeons at Columbia University, New York, NY, USA.
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29
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30
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Bioprosthetic Heart Valve Calcification: Clinicopathologic Correlations, Mechanisms, and Prevention. CONTEMPORARY CARDIOLOGY 2020. [DOI: 10.1007/978-3-030-46725-8_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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31
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Fioretta ES, Lintas V, Mallone A, Motta SE, von Boehmer L, Dijkman PE, Cesarovic N, Caliskan E, Rodriguez Cetina Biefer H, Lipiski M, Sauer M, Putti M, Janssen HM, Söntjens SH, Smits AI, Bouten CV, Emmert MY, Hoerstrup SP. Differential Leaflet Remodeling of Bone Marrow Cell Pre-Seeded Versus Nonseeded Bioresorbable Transcatheter Pulmonary Valve Replacements. JACC Basic Transl Sci 2019; 5:15-31. [PMID: 32043018 PMCID: PMC7000873 DOI: 10.1016/j.jacbts.2019.09.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/16/2019] [Accepted: 09/16/2019] [Indexed: 01/01/2023]
Abstract
Bone marrow mononuclear cell pre-seeding of polycarbonate bisurea–based tissue-engineered heart valves has detrimental effects on long-term performance and in situ remodeling and, therefore, should be avoided. Leaflet-specific analysis revealed pronounced remodeling differences with regard to cell infiltration, scaffold resorption, and extracellular matrix deposition within the same valve explant. The heterogeneity in remodeling of polycarbonate bisurea–based tissue-engineered heart valves may have important safety implications in terms of clinical translation. An in-depth understanding of the mechanobiological mechanisms involved in the in situ remodeling is required to limit the risk of unpredictable (maladaptive) remodeling.
This study showed that bone marrow mononuclear cell pre-seeding had detrimental effects on functionality and in situ remodeling of bioresorbable bisurea-modified polycarbonate (PC-BU)-based tissue-engineered heart valves (TEHVs) used as transcatheter pulmonary valve replacement in sheep. We also showed heterogeneous valve and leaflet remodeling, which affects PC-BU TEHV safety, challenging their potential for clinical translation. We suggest that bone marrow mononuclear cell pre-seeding should not be used in combination with PC-BU TEHVs. A better understanding of cell–scaffold interaction and in situ remodeling processes is needed to improve transcatheter valve design and polymer absorption rates for a safe and clinically relevant translation of this approach.
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Key Words
- B-GLAP, bone gamma-carboxyglutamate
- BMMNC, bone marrow mononuclear cells
- BVG, bioresorbable vascular graft
- CXCL12, stromal cell-derived factor-1α (SDF1α)
- ECM, extracellular matrix
- IL, interleukin
- MCP, monocyte chemoattractant protein
- MMP, matrix metalloproteinase
- PC-BU, polycarbonate bisurea
- SMA, smooth muscle actin
- TEE, transesophageal echocardiography
- TEHV, tissue-engineered heart valve
- TGF, transforming growth factor
- TVR, transcatheter valve replacement
- cardiovascular regenerative medicine
- endogenous tissue regeneration
- in situ tissue engineering
- supramolecular polymer
- tissue-engineered heart valve
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Affiliation(s)
| | - Valentina Lintas
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
- Wyss Translational Center Zürich, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Anna Mallone
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
| | - Sarah E. Motta
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
| | - Lisa von Boehmer
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
| | - Petra E. Dijkman
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
| | - Nikola Cesarovic
- Division of Surgical Research, University of Zürich, Zürich, Switzerland
- Department of Cardiovascular Surgery, University Hospital Zürich, Zürich, Switzerland
| | - Etem Caliskan
- Department of Cardiovascular Surgery, Charité Universitätsmedizin Berlin, Berlin, Germany
- Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany
| | | | - Miriam Lipiski
- Division of Surgical Research, University of Zürich, Zürich, Switzerland
| | - Mareike Sauer
- Division of Surgical Research, University of Zürich, Zürich, Switzerland
| | - Matilde Putti
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | | | | | - Anthal I.P.M. Smits
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Carlijn V.C. Bouten
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Maximilian Y. Emmert
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
- Wyss Translational Center Zürich, University of Zürich and ETH Zürich, Zürich, Switzerland
- Department of Cardiovascular Surgery, Charité Universitätsmedizin Berlin, Berlin, Germany
- Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany
- Address for correspondence: Dr. Maximilian Y. Emmert, Institute for Regenerative Medicine, Moussonstrasse 13, 8044 Zürich, Switzerland.
| | - Simon P. Hoerstrup
- Institute for Regenerative Medicine, University of Zürich, Zürich, Switzerland
- Wyss Translational Center Zürich, University of Zürich and ETH Zürich, Zürich, Switzerland
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
- Dr. Simon P. Hoerstrup, Institute for Regenerative Medicine, Moussonstrasse 13, 8044 Zürich, Switzerland.
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Liu L, Fei F, Zhang R, Wu F, Yang Q, Wang F, Sun S, Zhao H, Li Q, Wang L, Wang Y, Gui Y, Wang X. Combinatorial genetic replenishments in myocardial and outflow tract tissues restore heart function in tnnt2 mutant zebrafish. Biol Open 2019; 8:bio.046474. [PMID: 31796423 PMCID: PMC6918781 DOI: 10.1242/bio.046474] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cardiac muscle troponin T (Tnnt2) mediates muscle contraction in response to calcium ion dynamics, and Tnnt2 mutations are associated with multiple types of cardiomyopathy. Here, we employed a zebrafish model to investigate the genetic replenishment strategies of using conditional and inducible promoters to rescue the deficiencies in the heart. tnnt2a mutations were induced in zebrafish via the CRISPR/Cas9 technique, and the mutants displayed heart arrest and dilated cardiomyopathy-like phenotypes. We first utilized the classic myocardial promoter of the myl7 and TetOn inducible system to restore tnnt2a expression in myocardial tissue in tnnt2a mutant zebrafish. However, this attempt failed to recover normal heart function and circulation, although heart pumping was partially restored. Further analyses via both RNA-seq and immunofluorescence indicated that Tnnt2a, which was also expressed in a novel group of myl7-negative smooth muscle cells on the outflow tract (OFT), was indispensably responsible for the normal mechanical dynamics of OFT. Lastly, tnnt2 expression induced by OFT cells in addition to the myocardial cells successfully rescued heart function and circulation in tnnt2a mutant zebrafish. Together, our results reveal the significance of OFT expression of Tnnt2 for cardiac function and demonstrate zebrafish larva as a powerful and convenient in vivo platform for studying cardiomyopathy and the relevant therapeutic strategies.
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Affiliation(s)
- Lian Liu
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Fei Fei
- Cancer Metabolism Laboratory, Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Ranran Zhang
- Department of Pediatrics, the Affiliated Hospital of Qingdao University, Qingdao, Shangdong 266003, China
| | - Fang Wu
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Qian Yang
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Feng Wang
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Shaoyang Sun
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Hui Zhao
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
| | - Qiang Li
- Translational Medical Center for Development and Disease, Shanghai Key Laboratory of Birth Defect, Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Lei Wang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
| | - Youhua Wang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China
| | - Yonghao Gui
- Department of Cardiology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Xu Wang
- Cancer Metabolism Laboratory, Cancer Institute, Fudan University Shanghai Cancer Center, Shanghai 200032, China .,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai 230002, China
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Polyisobutylene-Based Thermoplastic Elastomers for Manufacturing Polymeric Heart Valve Leaflets: In Vitro and In Vivo Results. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9224773] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Superior polymers represent a promising alternative to mechanical and biological materials commonly used for manufacturing artificial heart valves. The study is aimed at assessing poly(styrene-block-isobutylene-block-styrene) (SIBS) properties and comparing them with polytetrafluoroethylene (Gore-texTM, a reference sample). Surface topography of both materials was evaluated with scanning electron microscopy and atomic force microscopy. The mechanical properties were measured under uniaxial tension. The water contact angle was estimated to evaluate hydrophilicity/hydrophobicity of the study samples. Materials’ hemocompatibility was evaluated using cell lines (Ea.hy 926), donor blood, and in vivo. SIBS possess a regular surface relief. It is hydrophobic and has lower strength as compared to Gore-texTM (3.51 MPa vs. 13.2/23.8 MPa). SIBS and Gore-texTM have similar hemocompatibility (hemolysis, adhesion, and platelet aggregation). The subcutaneous rat implantation reports that SIBS has a lower tendency towards calcification (0.39 mg/g) compared with Gore-texTM (1.29 mg/g). SIBS is a highly hemocompatible material with a promising potential for manufacturing heart valve leaflets, but its mechanical properties require further improvements. The possible options include the reinforcement with nanofillers and introductions of new chains in its structure.
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Taylor M, Shirani M, Dabiri Y, Guccione JM, Steigmann DJ. Finite elastic wrinkling deformations of incompressible fiber-reinforced plates. INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE 2019; 144:10.1016/j.ijengsci.2019.103138. [PMID: 32063652 PMCID: PMC7020621 DOI: 10.1016/j.ijengsci.2019.103138] [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
A two-dimensional plate theory, valid for finite elastic deformations with small strains, is derived for incompressible, fiber-reinforced materials. Single-layer plates and two-layer laminates are considered. Numerical simulations illustrate the substantial effect that fiber reinforcement has on wrinkling patterns in the sheet.
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Affiliation(s)
- M. Taylor
- Department of Mechanical Engineering, Santa Clara University, Santa Clara, CA 95053 USA
| | - M. Shirani
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720 USA
| | - Y. Dabiri
- Department of Surgery, University of California, San Francisco, CA 94143 USA
| | - J. M. Guccione
- Department of Surgery, University of California, San Francisco, CA 94143 USA
| | - D. J. Steigmann
- Department of Mechanical Engineering, University of California, Berkeley, CA 94720 USA
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Lejeune E, Sacks MS. Analyzing valve interstitial cell mechanics and geometry with spatial statistics. J Biomech 2019; 93:159-166. [PMID: 31383360 PMCID: PMC6858609 DOI: 10.1016/j.jbiomech.2019.06.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/11/2019] [Accepted: 06/28/2019] [Indexed: 02/07/2023]
Abstract
Understanding cell geometric and mechanical properties is crucial to understanding how cells sense and respond to their local environment. Moreover, changes to cell mechanical properties under varied micro-environmental conditions can both influence and indicate fundamental changes to cell behavior. Atomic Force Microscopy (AFM) is a well established, powerful tool to capture geometric and mechanical properties of cells. We have previously demonstrated substantial functional and behavioral differences between aortic and pulmonary valve interstitial cells (VIC) using AFM and subsequent models of VIC mechanical response. In the present work, we extend these studies by demonstrating that to best interpret the spatially distributed AFM data, the use of spatial statistics is required. Spatial statistics includes formal techniques to analyze spatially distributed data, and has been used successfully in the analysis of geographic data. Thus, spatially mapped AFM studies of cell geometry and mechanics are analogous to more traditional forms of geospatial data. We are able to compare the spatial autocorrelation of stiffness in aortic and pulmonary valve interstitial cells, and more accurately capture cell geometry from height recordings. Specifically, we showed that pulmonary valve interstitial cells display higher levels of spatial autocorrelation of stiffness than aortic valve interstitial cells. This suggests that aortic VICs form different stress fiber structures than their pulmonary counterparts, in addition to being more highly expressed and stiffer on average. Thus, the addition of spatial statistics can contribute to our fundamental understanding of the differences between cell types. Moving forward, we anticipate that this work will be meaningful to enhance direct analysis of experimental data and for constructing high fidelity computational of VICs and other cell models.
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Affiliation(s)
- Emma Lejeune
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Michael S Sacks
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Oden Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, United States.
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36
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Blomme B, Deroanne C, Hulin A, Lambert C, Defraigne JO, Nusgens B, Radermecker M, Colige A. Mechanical strain induces a pro-fibrotic phenotype in human mitral valvular interstitial cells through RhoC/ROCK/MRTF-A and Erk1/2 signaling pathways. J Mol Cell Cardiol 2019; 135:149-159. [PMID: 31442470 DOI: 10.1016/j.yjmcc.2019.08.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 08/13/2019] [Accepted: 08/19/2019] [Indexed: 01/16/2023]
Abstract
The mitral valve is a complex multilayered structure populated by fibroblast-like cells, valvular interstitial cells (VIC) which are embedded in an extracellular matrix (ECM) scaffold and are submitted to the mechanical deformations affecting valve at each heartbeat, for an average of 40 million times per year. Myxomatous mitral valve (MMV) is the most frequent heart valve disease characterized by disruption of several valvular structures due to alterations of their ECM preventing the complete closure of the valve resulting in symptoms of prolapse and regurgitation. VIC and their ECM exhibit reciprocal dynamic processes between the mechanical signals issued from the ECM and the modulation of VIC phenotype responsible for ECM homeostasis of the valve. Abnormal perception and responsiveness of VIC to mechanical stress may induce an inappropriate adaptative remodeling of the valve progressively leading to MMV. To investigate the response of human VIC to mechanical strain and identify the molecular mechanisms of mechano-transduction in these cells, a cyclic equibiaxial elongation of 14% at the cardiac frequency of 1.16 Hz was applied to VIC by using a Flexercell-4000 T™ apparatus for increasing time (from 1 h to 8 h). We showed that cyclic stretch induces an early (1 h) and transient over-expression of TGFβ2 and αSMA. CTGF, a profibrotic growth factor promoting the synthesis of ECM components, was strongly induced after 1 and 2 h of stretching and still upregulated at 8 h. The mechanical stress-induced CTGF up-regulation was dependent on RhoC, but not RhoA, as demonstrated by siRNA-mediated silencing approaches, and further supported by evidencing RhoC activation upon cell stretching and suppression of cell response by pharmacological inhibition of the effector ROCK1/2. It was also dependent on the MEK/Erk1/2 pathway which was activated by mechanical stress independently of RhoC and ROCK. Finally, mechanical stretching induced the nuclear translocation of myocardin related transcription factor-A (MRTF-A) which forms a transcriptional complex with SRF to promote the expression of target genes, notably CTGF. Treatment of stretched cultures with inhibitors of the identified pathways (ROCK1/2, MEK/Erk1/2, MRTF-A translocation) blocked CTGF overexpression and abrogated the increased MRTF-A nuclear translocation. CTGF is up-regulated in many pathological processes involving mechanically challenged organs, promotes ECM accumulation and is considered as a hallmark of fibrotic diseases. Pharmacological targeting of MRTF-A by newly developed inhibitors may represent a relevant therapy for MMV.
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Affiliation(s)
- Benoit Blomme
- Laboratory of Connective Tissues Biology, GIGA-Research, University of Liège, Tour de Pathologie, B23, 4000 Sart-Tilman, Belgium; Department of Cardiovascular and Thoracic Surgery, B35, University of Liège, CHU Sart-Tilman, 4000 Sart Tilman, Belgium
| | - Christophe Deroanne
- Laboratory of Connective Tissues Biology, GIGA-Research, University of Liège, Tour de Pathologie, B23, 4000 Sart-Tilman, Belgium
| | - Alexia Hulin
- Laboratory of Cardiology, GIGA-Cardiovascular Sciences, B34, University of Liège, 4000 Sart- Tilman, Belgium
| | - Charles Lambert
- Laboratory of Connective Tissues Biology, GIGA-Research, University of Liège, Tour de Pathologie, B23, 4000 Sart-Tilman, Belgium
| | - Jean-Olivier Defraigne
- Department of Cardiovascular and Thoracic Surgery, B35, University of Liège, CHU Sart-Tilman, 4000 Sart Tilman, Belgium
| | - Betty Nusgens
- Laboratory of Connective Tissues Biology, GIGA-Research, University of Liège, Tour de Pathologie, B23, 4000 Sart-Tilman, Belgium
| | - Marc Radermecker
- Department of Cardiovascular and Thoracic Surgery, B35, University of Liège, CHU Sart-Tilman, 4000 Sart Tilman, Belgium; Department of Human Anatomy, B23, University of Liège, CHU Sart-Tilman, 4000 Sart Tilman, Belgium
| | - Alain Colige
- Laboratory of Connective Tissues Biology, GIGA-Research, University of Liège, Tour de Pathologie, B23, 4000 Sart-Tilman, Belgium.
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37
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D'Amore A, Luketich SK, Hoff R, Ye SH, Wagner WR. Blending Polymer Labile Elements at Differing Scales to Affect Degradation Profiles in Heart Valve Scaffolds. Biomacromolecules 2019; 20:2494-2505. [PMID: 31083976 DOI: 10.1021/acs.biomac.9b00189] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
After more than 22 years of research challenges and innovation, the heart valve tissue engineering paradigm still attracts attention as an approach to overcome limitations which exist with clinically utilized mechanical or bioprosthetic heart valves. Despite encouraging results, delayed translation can be attributed to limited knowledge on the concurrent mechanisms of biomaterial degradation in vivo, host inflammatory response, cell recruitment, and de novo tissue elaboration. This study aimed to reduce this gap by evaluating three alternative levels at which lability could be incorporated into candidate polyurethane materials electroprocessed into a valve scaffold. Specifically, polyester and polycarbonate labile soft segment diols were reacted into thermoplastic elastomeric polyurethane ureas that formed scaffolds where (1) a single polyurethane containing both of the two diols in the polymer backbone was synthesized and processed, (2) two polyurethanes were physically blended, one with exclusively polycarbonate and one with exclusively polyester diols, followed by processing of the blend, and (3) the two polyurethane types were concurrently processed to form individual fiber populations in a valve scaffold. The resulting valve scaffolds were characterized in terms of their mechanics before and after exposure to varying periods of pulsatile flow in an enzymatic (lipase) buffer solution. The results showed that valve scaffolds made from the first type of polymer and processing combination experienced more extensive degradation. This approach, although demonstrated with polyurethane scaffolds, can generally be translated to investigate biomaterial approaches where labile elements are introduced at different structural levels to alter degradation properties while largely preserving the overall chemical composition and initial mechanical behavior.
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38
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Garner KH, Singla DK. 3D modeling: a future of cardiovascular medicine. Can J Physiol Pharmacol 2019; 97:277-286. [DOI: 10.1139/cjpp-2018-0472] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cardiovascular disease resulting from atypical cardiac structures continues to be a leading health concern despite advancements in diagnostic imaging and surgical techniques. However, the ability to visualize spatial relationships using current technologies remains a challenge. Therefore, 3D modeling has gained significant interest to understand complex and atypical cardiovascular disorders. Moreover, 3D modeling can be personalized and patient-specific. 3D models have been demonstrated to aid surgical planning and simulation, enhance communication among surgeons and patients, optimize medical device design, and can be used as a potential teaching tool in medical schools. In this review, we discuss the key components needed to generate cardiac 3D models. We highlight prevalent structural conditions that have utilized 3D modeling in pre-operative planning. Furthermore, we discuss the current limitations of routine use of 3D models in the clinic as well as future directions for utilization of this technology in the cardiovascular field.
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Affiliation(s)
- Kaley H. Garner
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
| | - Dinender K. Singla
- Division of Metabolic and Cardiovascular Sciences, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA
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Hutcheson JD, Goergen CJ, Schoen FJ, Aikawa M, Zilla P, Aikawa E, Gaudette GR. After 50 Years of Heart Transplants: What Does the Next 50 Years Hold for Cardiovascular Medicine? A Perspective From the International Society for Applied Cardiovascular Biology. Front Cardiovasc Med 2019; 6:8. [PMID: 30838213 PMCID: PMC6382669 DOI: 10.3389/fcvm.2019.00008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/24/2019] [Indexed: 12/24/2022] Open
Abstract
The first successful heart transplant 50 years ago by Dr.Christiaan Barnard in Cape Town, South Africa revolutionized cardiovascular medicine and research. Following this procedure, numerous other advances have reduced many contributors to cardiovascular morbidity and mortality; yet, cardiovascular disease remains the leading cause of death globally. Various unmet needs in cardiovascular medicine affect developing and underserved communities, where access to state-of-the-art advances remain out of reach. Addressing the remaining challenges in cardiovascular medicine in both developed and developing nations will require collaborative efforts from basic science researchers, engineers, industry, and clinicians. In this perspective, we discuss the advancements made in cardiovascular medicine since Dr. Barnard's groundbreaking procedure and ongoing research efforts to address these medical issues. Particular focus is given to the mission of the International Society for Applied Cardiovascular Biology (ISACB), which was founded in Cape Town during the 20th celebration of the first heart transplant in order to promote collaborative and translational research in the field of cardiovascular medicine.
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Affiliation(s)
- Joshua D Hutcheson
- Department of Biomedical Engineering, Florida International University, Miami, FL, United States
| | - Craig J Goergen
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, United States
| | - Frederick J Schoen
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Masanori Aikawa
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Peter Zilla
- Chris Barnard Division of Cardiothoracic Surgery, University of Cape Town, Cape Town, South Africa
| | - Elena Aikawa
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
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40
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Vashistha R, Kumar P, Dangi AK, Sharma N, Chhabra D, Shukla P. Quest for cardiovascular interventions: precise modeling and 3D printing of heart valves. J Biol Eng 2019; 13:12. [PMID: 30774709 PMCID: PMC6366048 DOI: 10.1186/s13036-018-0132-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/11/2018] [Indexed: 12/12/2022] Open
Abstract
Digitalization of health care practices is substantially manifesting itself as an effective tool to diagnose and rectify complex cardiovascular abnormalities. For cardiovascular abnormalities, precise non-invasive imaging interventions are being used to develop patient specific diagnosis and surgical planning. Concurrently, pre surgical 3D simulation and computational modeling are aiding in the effective surgery and understanding of valve biomechanics, respectively. Consequently, 3D printing of patient specific valves that can mimic the original one will become an effective outbreak for valvular problems. Printing of these patient-specific tissues or organ components is becoming a viable option owing to the advances in biomaterials and additive manufacturing techniques. These additive manufacturing techniques are receiving a full-fledged support from burgeoning field of computational fluid dynamics, digital image processing, artificial intelligence, and continuum mechanics during their optimization and implementation. Further, studies at cellular and molecular biomechanics have enriched our understanding of biomechanical factors resulting in valvular heart diseases. Hence, the knowledge generated can guide us during the design and synthesis of biomaterials to develop superior extra cellular matrix, mimicking materials that can be used as a bioink for 3D printing of organs and tissues. With this notion, we have reviewed current opportunities and challenges in the diagnosis and treatment of heart valve abnormalities through patient-specific valve design via tissue engineering and 3D bioprinting. These valves can replace diseased valves by preserving homogeneity and individuality of the patients.
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Affiliation(s)
- Rajat Vashistha
- Optimization and Mechatronics Laboratory, Department of Mechanical Engineering, University Institute of Engineering and Technology, Maharshi Dayanand University, Rohtak, Haryana India
| | - Prasoon Kumar
- Department of Medical Devices, National Institute of Pharmaceutical Education and Research Ahmadabad, Gandhinagar, Gujarat 382355 India
| | | | - Naveen Sharma
- Department of Cardiology, Shalby Hospitals, Jabalpur, India
| | - Deepak Chhabra
- Optimization and Mechatronics Laboratory, Department of Mechanical Engineering, University Institute of Engineering and Technology, Maharshi Dayanand University, Rohtak, Haryana India
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana 124001 India
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Khalighi AH, Rego BV, Drach A, Gorman RC, Gorman JH, Sacks MS. Development of a Functionally Equivalent Model of the Mitral Valve Chordae Tendineae Through Topology Optimization. Ann Biomed Eng 2019; 47:60-74. [PMID: 30187238 PMCID: PMC6516770 DOI: 10.1007/s10439-018-02122-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 08/23/2018] [Indexed: 12/11/2022]
Abstract
Ischemic mitral regurgitation (IMR) is a currently prevalent disease in the US that is projected to become increasingly common as the aging population grows. In recent years, image-based simulations of mitral valve (MV) function have improved significantly, providing new tools to refine IMR treatment. However, clinical implementation of MV simulations has long been hindered as the in vivo MV chordae tendineae (MVCT) geometry cannot be captured with sufficient fidelity for computational modeling. In the current study, we addressed this challenge by developing a method to produce functionally equivalent MVCT models that can be built from the image-based MV leaflet geometry alone. We began our analysis using extant micron-resolution 3D imaging datasets to first build anatomically accurate MV models. We then systematically simplified the native MVCT structure to generate a series of synthetic models by consecutively removing key anatomic features, such as the thickness variations, branching patterns, and chordal origin distributions. In addition, through topology optimization, we identified the minimal structural complexity required to capture the native MVCT behavior. To assess the performance and predictive power of each synthetic model, we analyzed their performance by comparing the mismatch in simulated MV closed shape, as well as the strain and stress tensors, to ground-truth MV models. Interestingly, our results revealed a substantial redundancy in the anatomic structure of native chordal anatomy. We showed that the closing behavior of complete MV apparatus under normal, diseased, and surgically repaired scenarios can be faithfully replicated by a functionally equivalent MVCT model comprised of two representative papillary muscle heads, single strand chords, and a uniform insertion distribution with a density of 15 insertions/cm2. Hence, even though the complete sub-valvular structure is mostly missing in in vivo MV images, we believe our approach will allow for the development of patient-specific complete MV models for surgical repair planning.
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Affiliation(s)
- Amir H Khalighi
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Bruno V Rego
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Andrew Drach
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael S Sacks
- James T. Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.
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42
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Rego BV, Khalighi AH, Drach A, Lai EK, Pouch AM, Gorman RC, Gorman JH, Sacks MS. A noninvasive method for the determination of in vivo mitral valve leaflet strains. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2018; 34:e3142. [PMID: 30133180 DOI: 10.1002/cnm.3142] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/21/2018] [Accepted: 08/07/2018] [Indexed: 06/08/2023]
Abstract
Assessment of mitral valve (MV) function is important in many diagnostic, prognostic, and surgical planning applications for treatment of MV disease. Yet, to date, there are no accepted noninvasive methods for determination of MV leaflet deformation, which is a critical metric of MV function. In this study, we present a novel, completely noninvasive computational method to estimate MV leaflet in-plane strains from clinical-quality real-time three-dimensional echocardiography (rt-3DE) images. The images were first segmented to produce meshed medial-surface leaflet geometries of the open and closed states. To establish material point correspondence between the two states, an image-based morphing pipeline was implemented within a finite element (FE) modeling framework in which MV closure was simulated by pressurizing the open-state geometry, and local corrective loads were applied to enforce the actual MV closed shape. This resulted in a complete map of local systolic leaflet membrane strains, obtained from the final FE mesh configuration. To validate the method, we utilized an extant in vitro database of fiducially labeled MVs, imaged in conditions mimicking both the healthy and diseased states. Our method estimated local anisotropic in vivo strains with less than 10% error and proved to be robust to changes in boundary conditions similar to those observed in ischemic MV disease. Next, we applied our methodology to ovine MVs imaged in vivo with rt-3DE and compared our results to previously published findings of in vivo MV strains in the same type of animal as measured using surgically sutured fiducial marker arrays. In regions encompassed by fiducial markers, we found no significant differences in circumferential(P = 0.240) or radial (P = 0.808) strain estimates between the marker-based measurements and our novel noninvasive method. This method can thus be used for model validation as well as for studies of MV disease and repair.
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Affiliation(s)
- Bruno V Rego
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas
| | - Amir H Khalighi
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas
| | - Andrew Drach
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas
| | - Eric K Lai
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Alison M Pouch
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael S Sacks
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas
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Menon V, Lincoln J. The Genetic Regulation of Aortic Valve Development and Calcific Disease. Front Cardiovasc Med 2018; 5:162. [PMID: 30460247 PMCID: PMC6232166 DOI: 10.3389/fcvm.2018.00162] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/19/2018] [Indexed: 12/19/2022] Open
Abstract
Heart valves are dynamic, highly organized structures required for unidirectional blood flow through the heart. Over an average lifetime, the valve leaflets or cusps open and close over a billion times, however in over 5 million Americans, leaflet function fails due to biomechanical insufficiency in response to wear-and-tear or pathological stimulus. Calcific aortic valve disease (CAVD) is the most common valve pathology and leads to stiffening of the cusp and narrowing of the aortic orifice leading to stenosis and insufficiency. At the cellular level, CAVD is characterized by valve endothelial cell dysfunction and osteoblast-like differentiation of valve interstitial cells. These processes are associated with dysregulation of several molecular pathways important for valve development including Notch, Sox9, Tgfβ, Bmp, Wnt, as well as additional epigenetic regulators. In this review, we discuss the multifactorial mechanisms that contribute to CAVD pathogenesis and the potential of targeting these for the development of novel, alternative therapeutics beyond surgical intervention.
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Affiliation(s)
- Vinal Menon
- Center for Cardiovascular Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,The Heart Center, Nationwide Children's Hospital, Columbus, OH, United States
| | - Joy Lincoln
- Center for Cardiovascular Research, The Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,The Heart Center, Nationwide Children's Hospital, Columbus, OH, United States.,Department of Pediatrics, Ohio State University, Columbus, OH, United States
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Maeda K, Ma X, Hanley FL, Riemer RK. Modeling Impaired Coaptation Effects on Mitral Leaflet Homeostasis Using a Flow-Culture Bioreactor. Ann Thorac Surg 2018; 107:512-518. [PMID: 30365966 DOI: 10.1016/j.athoracsur.2018.08.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 08/02/2018] [Accepted: 08/31/2018] [Indexed: 10/28/2022]
Abstract
BACKGROUND Mitral valve (MV) regurgitation constitutes an increasing burden of adult and pediatric cardiac disease tending to worsen over time. Whether altered mechanical forces on leaflets cause valve disease is unknown. Here we show that MV leaflet coaptive strain disruption alters expression of genes critical to leaflet homeostasis. METHODS We used a flow-culture bioreactor of rat MVs with flow-induced cyclic coaptation (cycling valve group; n = 4) or in a sustained open state (open valve group; n = 4). After 3 days of culture, leaflet RNA expression was profiled. RESULTS More than 48 genes exhibited markedly changed expression when coaptive leaflet strain was disrupted for 3 days (change >fourfold; p < 0.05; cycling vs open valves). Genes exhibiting highly altered expression included Angpt2, Vegf, Cd74, RT1-Da (HLA-DRA), and Igfbp3. Pathway analysis indicated the most significant signaling pathways regulating the expression changes were Hif1α and Tnfα when MV closure was disrupted. CONCLUSIONS Disruption of normal MV coaptive strain markedly alters the expression of leaflet genes, demonstrating that cyclic strain is critically important to leaflet homeostasis. We demonstrate a pattern of MV gene expression changes in which hypoxia signaling is prominently increased in response to disrupted strain cycles. Coaptive strain regulation of MV leaflet homeostasis implicates altered strain as a mechanism potentially initiating valve disease. Early repair may prevent progression of disease driven by altered coaptation.
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Affiliation(s)
- Katsuhide Maeda
- Pediatric Cardiac Surgery Division, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California
| | - Xiaoyuan Ma
- Pediatric Cardiac Surgery Division, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California
| | - Frank L Hanley
- Pediatric Cardiac Surgery Division, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California
| | - R Kirk Riemer
- Pediatric Cardiac Surgery Division, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California.
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Ayoub S, Tsai KC, Khalighi AH, Sacks MS. The Three-Dimensional Microenvironment of the Mitral Valve: Insights into the Effects of Physiological Loads. Cell Mol Bioeng 2018; 11:291-306. [PMID: 31719888 PMCID: PMC6816749 DOI: 10.1007/s12195-018-0529-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 05/14/2018] [Indexed: 10/24/2022] Open
Abstract
INTRODUCTION In the mitral valve (MV), numerous pathological factors, especially those resulting from changes in external loading, have been shown to affect MV structure and composition. Such changes are driven by the MV interstitial cell (MVIC) population via protein synthesis and enzymatic degradation of extracellular matrix (ECM) components. METHODS While cell phenotype, ECM composition and regulation, and tissue level changes in MVIC shape under stress have been studied, a detailed understanding of the three-dimensional (3D) microstructural mechanisms are lacking. As a first step in addressing this challenge, we applied focused ion beam scanning electron microscopy (FIB-SEM) to reveal novel details of the MV microenvironment in 3D. RESULTS We demonstrated that collagen is organized into large fibers consisting of an average of 605 ± 113 fibrils, with a mean diameter of 61.2 ± 9.8 nm. In contrast, elastin was organized into two distinct structural subtypes: (1) sheet-like lamellar elastin, and (2) circumferentially oriented elastin struts, based on both the aspect ratio and transmural tilt. MVICs were observed to have a large cytoplasmic volume, as evidenced by the large mean surface area to volume ratio 3.68 ± 0.35, which increased under physiological loading conditions to 4.98 ± 1.17. CONCLUSIONS Our findings suggest that each MVIC mechanically interacted only with the nearest 3-4 collagen fibers. This key observation suggests that in developing multiscale MV models, each MVIC can be considered a mechanically integral part of the local fiber ensemble and is unlikely to be influenced by more distant structures.
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Affiliation(s)
- Salma Ayoub
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, 201 East 24th Street, POB 5.236, 1 University Station C0200, Austin, TX 78712 USA
| | - Karen C. Tsai
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, 201 East 24th Street, POB 5.236, 1 University Station C0200, Austin, TX 78712 USA
| | - Amir H. Khalighi
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, 201 East 24th Street, POB 5.236, 1 University Station C0200, Austin, TX 78712 USA
| | - Michael S. Sacks
- Willerson Center for Cardiovascular Modeling and Simulation, Institute for Computational Engineering and Sciences and the Department of Biomedical Engineering, The University of Texas at Austin, 201 East 24th Street, POB 5.236, 1 University Station C0200, Austin, TX 78712 USA
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Sievers HH, Schubert K, Jamali A, Scharfschwerdt M. The influence of different inflow configurations on computational fluid dynamics in a novel three-leaflet mechanical heart valve prosthesis. Interact Cardiovasc Thorac Surg 2018; 27:475-480. [DOI: 10.1093/icvts/ivy086] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/22/2018] [Indexed: 01/08/2023] Open
Affiliation(s)
- Hans-Hinrich Sievers
- Department of Cardiac and Thoracic Vascular Surgery, University of Luebeck, Luebeck, Germany
| | - Kathrin Schubert
- Department of Cardiac and Thoracic Vascular Surgery, University of Luebeck, Luebeck, Germany
| | - Ashkan Jamali
- Department of Cardiac and Thoracic Vascular Surgery, University of Luebeck, Luebeck, Germany
| | - Michael Scharfschwerdt
- Department of Cardiac and Thoracic Vascular Surgery, University of Luebeck, Luebeck, Germany
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Drach A, Khalighi AH, Sacks MS. A comprehensive pipeline for multi-resolution modeling of the mitral valve: Validation, computational efficiency, and predictive capability. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2018; 34:10.1002/cnm.2921. [PMID: 28776326 PMCID: PMC5797517 DOI: 10.1002/cnm.2921] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/26/2017] [Accepted: 07/28/2017] [Indexed: 05/18/2023]
Abstract
Multiple studies have demonstrated that the pathological geometries unique to each patient can affect the durability of mitral valve (MV) repairs. While computational modeling of the MV is a promising approach to improve the surgical outcomes, the complex MV geometry precludes use of simplified models. Moreover, the lack of complete in vivo geometric information presents significant challenges in the development of patient-specific computational models. There is thus a need to determine the level of detail necessary for predictive MV models. To address this issue, we have developed a novel pipeline for building attribute-rich computational models of MV with varying fidelity directly from the in vitro imaging data. The approach combines high-resolution geometric information from loaded and unloaded states to achieve a high level of anatomic detail, followed by mapping and parametric embedding of tissue attributes to build a high-resolution, attribute-rich computational models. Subsequent lower resolution models were then developed and evaluated by comparing the displacements and surface strains to those extracted from the imaging data. We then identified the critical levels of fidelity for building predictive MV models in the dilated and repaired states. We demonstrated that a model with a feature size of about 5 mm and mesh size of about 1 mm was sufficient to predict the overall MV shape, stress, and strain distributions with high accuracy. However, we also noted that more detailed models were found to be needed to simulate microstructural events. We conclude that the developed pipeline enables sufficiently complex models for biomechanical simulations of MV in normal, dilated, repaired states.
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Affiliation(s)
- Andrew Drach
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Amir H Khalighi
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Michael S Sacks
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
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Motta SE, Lintas V, Fioretta ES, Hoerstrup SP, Emmert MY. Off-the-shelf tissue engineered heart valves for in situ regeneration: current state, challenges and future directions. Expert Rev Med Devices 2017; 15:35-45. [PMID: 29257706 DOI: 10.1080/17434440.2018.1419865] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Transcatheter aortic valve replacement (TAVR) is continuously evolving and is expected to surpass surgical valve implantation in the near future. Combining durable valve substitutes with minimally invasive implantation techniques might increase the clinical relevance of this therapeutic option for younger patient populations. Tissue engineering offers the possibility to create tissue engineered heart valves (TEHVs) with regenerative and self-repair capacities which may overcome the pitfalls of current TAVR prostheses. AREAS COVERED This review focuses on off-the-shelf TEHVs which rely on a clinically-relevant in situ tissue engineering approach and which have already advanced into preclinical or first-in-human investigation. EXPERT COMMENTARY Among the off-the-shelf in situ TEHVs reported in literature, the vast majority covers pulmonary valve substitutes, and only few are combined with transcatheter implantation technologies. Hence, further innovations should include the development of transcatheter tissue engineered aortic valve substitutes, which would considerably increase the clinical relevance of such prostheses.
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Affiliation(s)
- Sarah E Motta
- a Institute for Regenerative Medicine (IREM) , University of Zurich , Zurich , Switzerland
| | - Valentina Lintas
- a Institute for Regenerative Medicine (IREM) , University of Zurich , Zurich , Switzerland
| | - Emanuela S Fioretta
- a Institute for Regenerative Medicine (IREM) , University of Zurich , Zurich , Switzerland
| | - Simon P Hoerstrup
- a Institute for Regenerative Medicine (IREM) , University of Zurich , Zurich , Switzerland.,b Wyss Translational Center Zurich , University and ETH Zurich , Zurich , Switzerland
| | - Maximilian Y Emmert
- a Institute for Regenerative Medicine (IREM) , University of Zurich , Zurich , Switzerland.,b Wyss Translational Center Zurich , University and ETH Zurich , Zurich , Switzerland.,c Heart Center Zurich , University Hospital Zurich , Zurich , Switzerland
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Khalighi AH, Drach A, Gorman RC, Gorman JH, Sacks MS. Multi-resolution geometric modeling of the mitral heart valve leaflets. Biomech Model Mechanobiol 2017; 17:351-366. [PMID: 28983742 DOI: 10.1007/s10237-017-0965-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/18/2017] [Indexed: 10/18/2022]
Abstract
An essential element of cardiac function, the mitral valve (MV) ensures proper directional blood flow between the left heart chambers. Over the past two decades, computational simulations have made marked advancements toward providing powerful predictive tools to better understand valvular function and improve treatments for MV disease. However, challenges remain in the development of robust means for the quantification and representation of MV leaflet geometry. In this study, we present a novel modeling pipeline to quantitatively characterize and represent MV leaflet surface geometry. Our methodology utilized a two-part additive decomposition of the MV geometric features to decouple the macro-level general leaflet shape descriptors from the leaflet fine-scale features. First, the general shapes of five ovine MV leaflets were modeled using superquadric surfaces. Second, the finer-scale geometric details were captured, quantified, and reconstructed via a 2D Fourier analysis with an additional sparsity constraint. This spectral approach allowed us to easily control the level of geometric details in the reconstructed geometry. The results revealed that our methodology provided a robust and accurate approach to develop MV-specific models with an adjustable level of spatial resolution and geometric detail. Such fully customizable models provide the necessary means to perform computational simulations of the MV at a range of geometric accuracies in order to identify the level of complexity required to achieve predictive MV simulations.
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Affiliation(s)
- Amir H Khalighi
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Andrew Drach
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael S Sacks
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, USA.
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50
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Ayoub S, Lee CH, Driesbaugh KH, Anselmo W, Hughes CT, Ferrari G, Gorman RC, Gorman JH, Sacks MS. Regulation of valve interstitial cell homeostasis by mechanical deformation: implications for heart valve disease and surgical repair. J R Soc Interface 2017; 14:20170580. [PMID: 29046338 PMCID: PMC5665836 DOI: 10.1098/rsif.2017.0580] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/21/2017] [Indexed: 11/12/2022] Open
Abstract
Mechanical stress is one of the major aetiological factors underlying soft-tissue remodelling, especially for the mitral valve (MV). It has been hypothesized that altered MV tissue stress states lead to deviations from cellular homeostasis, resulting in subsequent cellular activation and extracellular matrix (ECM) remodelling. However, a quantitative link between alterations in the organ-level in vivo state and in vitro-based mechanobiology studies has yet to be made. We thus developed an integrated experimental-computational approach to elucidate MV tissue and interstitial cell responses to varying tissue strain levels. Comprehensive results at different length scales revealed that normal responses are observed only within a defined range of tissue deformations, whereas deformations outside of this range lead to hypo- and hyper-synthetic responses, evidenced by changes in α-smooth muscle actin, type I collagen, and other ECM and cell adhesion molecule regulation. We identified MV interstitial cell deformation as a key player in leaflet tissue homeostatic regulation and, as such, used it as the metric that makes the critical link between in vitro responses to simulated equivalent in vivo behaviour. Results indicated that cell responses have a delimited range of in vivo deformations that maintain a homeostatic response, suggesting that deviations from this range may lead to deleterious tissue remodelling and failure.
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Affiliation(s)
- Salma Ayoub
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences (ICES), Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
| | - Chung-Hao Lee
- School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, OK 73019, USA
| | - Kathryn H Driesbaugh
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Wanda Anselmo
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Connor T Hughes
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences (ICES), Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
| | - Giovanni Ferrari
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Robert C Gorman
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Joseph H Gorman
- Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael S Sacks
- Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences (ICES), Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA
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