1
|
Szafron JM, Heng EE, Boyd J, Humphrey JD, Marsden AL. Hemodynamics and Wall Mechanics of Vascular Graft Failure. Arterioscler Thromb Vasc Biol 2024; 44:1065-1085. [PMID: 38572650 PMCID: PMC11043008 DOI: 10.1161/atvbaha.123.318239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 03/12/2024] [Indexed: 04/05/2024]
Abstract
Blood vessels are subjected to complex biomechanical loads, primarily from pressure-driven blood flow. Abnormal loading associated with vascular grafts, arising from altered hemodynamics or wall mechanics, can cause acute and progressive vascular failure and end-organ dysfunction. Perturbations to mechanobiological stimuli experienced by vascular cells contribute to remodeling of the vascular wall via activation of mechanosensitive signaling pathways and subsequent changes in gene expression and associated turnover of cells and extracellular matrix. In this review, we outline experimental and computational tools used to quantify metrics of biomechanical loading in vascular grafts and highlight those that show potential in predicting graft failure for diverse disease contexts. We include metrics derived from both fluid and solid mechanics that drive feedback loops between mechanobiological processes and changes in the biomechanical state that govern the natural history of vascular grafts. As illustrative examples, we consider application-specific coronary artery bypass grafts, peripheral vascular grafts, and tissue-engineered vascular grafts for congenital heart surgery as each of these involves unique circulatory environments, loading magnitudes, and graft materials.
Collapse
Affiliation(s)
- Jason M Szafron
- Departments of Pediatrics (J.M.S., A.L.M.), Stanford University, CA
| | - Elbert E Heng
- Cardiothoracic Surgery (E.E.H., J.B.), Stanford University, CA
| | - Jack Boyd
- Cardiothoracic Surgery (E.E.H., J.B.), Stanford University, CA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT (J.D.H.)
| | | |
Collapse
|
2
|
Umeno T, Mori K, Iwai R, Kawashima T, Shuto T, Nakashima Y, Tajikawa T, Nakayama Y, Miyamoto S. Carotid Artery Bypass Surgery of In-Body Tissue Architecture-Induced Small-Diameter Biotube in a Goat Model: A Pilot Study. Bioengineering (Basel) 2024; 11:203. [PMID: 38534477 DOI: 10.3390/bioengineering11030203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/31/2024] [Accepted: 02/19/2024] [Indexed: 03/28/2024] Open
Abstract
Biotubes are autologous tubular tissues developed within a patient's body through in-body tissue architecture, and they demonstrate high potential for early clinical application as a vascular replacement. In this pilot study, we used large animals to perform implantation experiments in preparation for preclinical testing of Biotube. The biological response after Biotube implantation was histologically evaluated. The designed Biotubes (length: 50 cm, internal diameter: 4 mm, and wall thickness: 0.85 mm) were obtained by embedding molds on the backs of six goats for a predetermined period (1-5 months). The same goats underwent bypass surgery on the carotid arteries using Biotubes (average length: 12 cm). After implantation, echocardiography was used to periodically monitor patency and blood flow velocity. The maximum observation period was 6 months, and tissue analysis was conducted after graft removal, including the anastomosis. All molds generated Biotubes that exceeded the tensile strength of normal goat carotid arteries, and eight randomly selected Biotubes were implanted. Thrombotic occlusion occurred immediately postoperatively (1 tube) if anticoagulation was insufficient, and two tubes, with insufficient Biotube strength (<5 N), were ruptured within a week. Five tubes maintained patency for >2 months without aneurysm formation. The spots far from the anastomosis became stenosed within 3 months (3 tubes) when Biotubes had a wide intensity distribution, but the shape of the remaining two tubes remained unchanged for 6 months. The entire length of the bypass region was walled with an αSMA-positive cell layer, and an endothelial cell layer covered most of the lumen at 2 months. Complete endothelial laying of the luminal surface was obtained at 3 months after implantation, and a vascular wall structure similar to that of native blood vessels was formed, which was maintained even at 6 months. The stenosis was indicated to be caused by fibrin adhesion on the luminal surface, migration of repair macrophages, and granulation formation due to the overproliferation of αSMA-positive fibroblasts. We revealed the importance of Biotubes that are homogeneous, demonstrate a tensile strength > 5 N, and are implanted under appropriate antithrombotic conditions to achieve long-term patency of Biotube. Further, we clarified the Biotube regeneration process and the mechanism of stenosis. Finally, we obtained the necessary conditions for a confirmatory implant study planned shortly.
Collapse
Affiliation(s)
- Tadashi Umeno
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| | - Kazuki Mori
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| | - Ryosuke Iwai
- Institute of Frontier Science and Technology, Okayama University of Science, Okayama 700-0005, Japan
| | - Takayuki Kawashima
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| | - Takashi Shuto
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| | - Yumiko Nakashima
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| | - Tsutomu Tajikawa
- Department of Mechanical Engineering, Faculty of Engineering Science, Kansai University, Osaka 564-8680, Japan
| | | | - Shinji Miyamoto
- Department of Cardiovascular Surgery, Oita University Hospital, Oita 879-5593, Japan
| |
Collapse
|
3
|
Bartlett M, Bonfanti M, Diaz-Zuccarini V, Tsui J. Computationally Enhanced, Haemodynamic Case Study of Neointimal Hyperplasia Development in a Dialysis Access Fistula. Rev Cardiovasc Med 2024; 25:35. [PMID: 39077669 PMCID: PMC11262387 DOI: 10.31083/j.rcm2501035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 11/17/2023] [Accepted: 11/21/2023] [Indexed: 07/31/2024] Open
Abstract
Background Oscillatory wall shear stress and related metrics have been identified as potential predictors of dialysis access outcomes; however, the absence of a simple non-invasive method for measuring these haemodynamic forces has been prohibitive to their adoption into routine clinical practice. We present a computationally enhanced, single patient case study, offering a unique insight into the haemodynamic environment surrounding the development of flow limiting neointimal hyperplasia within the efferent vein of a previously functional arteriovenous fistula (AVF). Methods Computational fluid dynamics (CFD) simulations were used to create a quantitative map of oscillatory shear stress as well as enabling visualisation of streamline patterns within the AVF. CFD data was compared to ultrasound-based turbulence quantification and examined alongside structural and functional changes in the access site over time. Results This work further supports the notion that flow limiting neointimal hyperplasia development in vascular access fistulae, occurs in response to oscillatory wall shear stress, and provides proof of concept for the idea that non-invasive ultrasound turbulence quantification tools could play a role in predicting vascular access outcomes. Conclusions In addition to providing insight into the haemodynamic environment surrounding the development of flow limiting neointimal hyperplasia, we hope that this paper will promote discussion and further thinking about how our learnings from in-silico studies can be incorporated into clinical practice through novel uses of existing diagnostic tools.
Collapse
Affiliation(s)
- Matthew Bartlett
- Division of Surgery & Interventional Science, University College London, Royal Free Campus, NW3 2QG London, UK
- Department of Vascular Surgery, Royal Free London NHS Foundation Trust, NW3 2QG London, UK
| | - Mirko Bonfanti
- Department of Mechanical Engineering, University College London, WC1E 7JE London, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences (WEISS), Department of Medical Physics and Biomedical Engineering, University College London, W1W 7TS London, UK
| | - Vanessa Diaz-Zuccarini
- Department of Mechanical Engineering, University College London, WC1E 7JE London, UK
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences (WEISS), Department of Medical Physics and Biomedical Engineering, University College London, W1W 7TS London, UK
| | - Janice Tsui
- Division of Surgery & Interventional Science, University College London, Royal Free Campus, NW3 2QG London, UK
- Department of Vascular Surgery, Royal Free London NHS Foundation Trust, NW3 2QG London, UK
| |
Collapse
|
4
|
Ninno F, Tsui J, Balabani S, Díaz-Zuccarini V. A systematic review of clinical and biomechanical engineering perspectives on the prediction of restenosis in coronary and peripheral arteries. JVS Vasc Sci 2023; 4:100128. [PMID: 38023962 PMCID: PMC10663814 DOI: 10.1016/j.jvssci.2023.100128] [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: 03/01/2023] [Accepted: 09/10/2023] [Indexed: 12/01/2023] Open
Abstract
Objective Restenosis is a significant complication of revascularization treatments in coronary and peripheral arteries, sometimes necessitating repeated intervention. Establishing when restenosis will happen is extremely difficult due to the interplay of multiple variables and factors. Standard clinical and Doppler ultrasound scans surveillance follow-ups are the only tools clinicians can rely on to monitor intervention outcomes. However, implementing efficient surveillance programs is hindered by health care system limitations, patients' comorbidities, and compliance. Predictive models classifying patients according to their risk of developing restenosis over a specific period will allow the development of tailored surveillance, prevention programs, and efficient clinical workflows. This review aims to: (1) summarize the state-of-the-art in predictive models for restenosis in coronary and peripheral arteries; (2) compare their performance in terms of predictive power; and (3) provide an outlook for potentially improved predictive models. Methods We carried out a comprehensive literature review by accessing the PubMed/MEDLINE database according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search strategy consisted of a combination of keywords and included studies focusing on predictive models of restenosis published between January 1993 and April 2023. One author independently screened titles and abstracts and checked for eligibility. The rest of the authors independently confirmed and discussed in case of any disagreement. The search of published literature identified 22 studies providing two perspectives-clinical and biomechanical engineering-on restenosis and comprising distinct methodologies, predictors, and study designs. We compared predictive models' performance on discrimination and calibration aspects. We reported the performance of models simulating reocclusion progression, evaluated by comparison with clinical images. Results Clinical perspective studies consider only routinely collected patient information as restenosis predictors. Our review reveals that clinical models adopting traditional statistics (n = 14) exhibit only modest predictive power. The latter improves when machine learning algorithms (n = 4) are employed. The logistic regression models of the biomechanical engineering perspective (n = 2) show enhanced predictive power when hemodynamic descriptors linked to restenosis are fused with a limited set of clinical risk factors. Biomechanical engineering studies simulating restenosis progression (n = 2) are able to capture its evolution but are computationally expensive and lack risk scoring for individual patients at specific follow-ups. Conclusions Restenosis predictive models, based solely on routine clinical risk factors and using classical statistics, inadequately predict the occurrence of restenosis. Risk stratification models with increased predictive power can be potentially built by adopting machine learning techniques and incorporating critical information regarding vessel hemodynamics arising from biomechanical engineering analyses.
Collapse
Affiliation(s)
- Federica Ninno
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, London, United Kingdom
| | - Janice Tsui
- Department of Vascular Surgery, Royal Free Hospital NHS Foundation Trust, London, United Kingdom
- Division of Surgery & Interventional Science, Department of Surgical Biotechnology, Faculty of Medical Sciences, University College London, Royal Free Campus, London, United Kingdom
| | - Stavroula Balabani
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, London, United Kingdom
- Department of Mechanical Engineering, University College London, London, United Kingdom
| | - Vanessa Díaz-Zuccarini
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, London, United Kingdom
- Department of Mechanical Engineering, University College London, London, United Kingdom
| |
Collapse
|
5
|
He Y, Tran-Son-Tay R, Berceli SA. Distinct Temporal Pattern of the Prediction of Lumen Remodeling of Lower Extremity Vein Bypass Grafts by Initial Local Hemodynamics. Ann Biomed Eng 2023; 51:296-307. [PMID: 35881266 DOI: 10.1007/s10439-022-03019-7] [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: 05/04/2022] [Accepted: 07/05/2022] [Indexed: 01/25/2023]
Abstract
We predicted human lower extremity vein bypass graft remodeling by hemodynamics. Computed tomography and duplex ultrasound scans of 55 patients were performed at 1 week and 1, 6, and 12 months post-implantation to obtain wall shear stress (WSS) and oscillatory shear index (OSI) at 1-mm intervals via computational fluid dynamics simulations. Graft remodeling was quantified by computed tomography-measured lumen diameter changes in the early (1 week-1 month), intermediate (1-6 months), and late (6-12 months) periods. Linear mixed-effect models were constructed to examine the overall relationship between remodeling and initial hemodynamics using the average data of all cross sections within the same graft. A significant association of graft remodeling with WSS (p < 0.001) and time (p = 0.001) was found; however, the effect size decreased with time (every 2.7 dyne/cm2 increase of WSS was associated with a 0.39, 0.35, 0.002 mm diameter increase in the three periods, respectively). The association of remodeling with OSI was significant only in the intermediate period (every 0.1 increase of OSI was associated with a 0.25 mm lumen diameter decrease, p = 0.004). Therefore, the association of graft lumen remodeling with local hemodynamics has a distinct temporal pattern; WSS and OSI are predictive of remodeling only in certain postoperative periods.
Collapse
Affiliation(s)
- Yong He
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, University of Florida, PO Box 100128, Gainesville, FL, 32610-0286, USA. .,The Vascular Surgery Section, Malcom Randall Veterans Affairs Medical Center, Gainesville, FL, USA.
| | - Roger Tran-Son-Tay
- Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, USA
| | - Scott A Berceli
- Department of Surgery, Division of Vascular Surgery and Endovascular Therapy, University of Florida, PO Box 100128, Gainesville, FL, 32610-0286, USA.,The Vascular Surgery Section, Malcom Randall Veterans Affairs Medical Center, Gainesville, FL, USA
| |
Collapse
|
6
|
Tan W, Boodagh P, Selvakumar PP, Keyser S. Strategies to counteract adverse remodeling of vascular graft: A 3D view of current graft innovations. Front Bioeng Biotechnol 2023; 10:1097334. [PMID: 36704297 PMCID: PMC9871289 DOI: 10.3389/fbioe.2022.1097334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 12/23/2022] [Indexed: 01/11/2023] Open
Abstract
Vascular grafts are widely used for vascular surgeries, to bypass a diseased artery or function as a vascular access for hemodialysis. Bioengineered or tissue-engineered vascular grafts have long been envisioned to take the place of bioinert synthetic grafts and even vein grafts under certain clinical circumstances. However, host responses to a graft device induce adverse remodeling, to varied degrees depending on the graft property and host's developmental and health conditions. This in turn leads to invention or failure. Herein, we have mapped out the relationship between the design constraints and outcomes for vascular grafts, by analyzing impairment factors involved in the adverse graft remodeling. Strategies to tackle these impairment factors and counteract adverse healing are then summarized by outlining the research landscape of graft innovations in three dimensions-cell technology, scaffold technology and graft translation. Such a comprehensive view of cell and scaffold technological innovations in the translational context may benefit the future advancements in vascular grafts. From this perspective, we conclude the review with recommendations for future design endeavors.
Collapse
Affiliation(s)
- Wei Tan
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, CO, United States,*Correspondence: Wei Tan,
| | - Parnaz Boodagh
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | | | - Sean Keyser
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, CO, United States
| |
Collapse
|