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Hohri Y, Chung MM, Kandula V, Kim I, Leb J, Hayashi H, Elmously A, O’Donnell TFX, Patel V, Vedula V, Takayama H. Blood flow assessment technology in aortic surgery: a narrative review. J Thorac Dis 2024; 16:2623-2636. [PMID: 38738252 PMCID: PMC11087597 DOI: 10.21037/jtd-23-1795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/23/2024] [Indexed: 05/14/2024]
Abstract
Background and Objective Blood flow assessment is an emerging technique that allows for assessment of hemodynamics in the heart and blood vessels. Recent advances in cardiovascular imaging technologies have made it possible for this technique to be more accessible to clinicians and researchers. Blood flow assessment typically refers to two techniques: measurement-based flow visualization using echocardiography or four-dimensional flow magnetic resonance imaging (4D flow MRI), and computer-based flow simulation based on computational fluid dynamics modeling. Using these methods, blood flow patterns can be visualized and quantitative measurements of mechanical stress on the walls of the ventricles and blood vessels, most notably the aorta, can be made. Thus, blood flow assessment has been enhancing the understanding of cardiac and aortic diseases; however, its introduction to clinical practice has been negligible yet. In this article, we aim to discuss the clinical applications and future directions of blood flow assessment in aortic surgery. We then provide our unique perspective on the technique's translational impact on the surgical management of aortic disease. Methods Articles from the PubMed database and Google Scholar regarding blood flow assessment in aortic surgery were reviewed. For the initial search, articles published between 2013 and 2023 were prioritized, including original articles, clinical trials, case reports, and reviews. Following the initial search, additional articles were considered based on manual searches of the references from the retrieved literature. Key Content and Findings In aortic root pathology and ascending aortic aneurysms, blood flow assessment can elucidate postoperative hemodynamic changes after surgical reconfiguration of the aortic valve complex or ascending aorta. In cases of aortic dissection, analysis of blood flow can predict future aortic dilatation. For complicated congenital aortic anomalies, surgeons may use preoperative imaging to perform "virtual surgery", in which blood flow assessment can predict postoperative hemodynamics for different surgical reconstructions and assist in procedural planning even before entering the operating room. Conclusions Blood flow assessment and computational modeling can evaluate hemodynamics and flow patterns by visualizing blood flow and calculating biomechanical forces in patients with aortic disease. We anticipate that blood flow assessment will become an essential tool in the treatment planning and understanding of the progression of aortic disease.
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Affiliation(s)
- Yu Hohri
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Megan M. Chung
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Viswajit Kandula
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Ilya Kim
- Department of Medicine, New York-Presbyterian Hospital, Weill Cornell Medical Center, New York, NY, USA
| | - Jay Leb
- Department of Radiology, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Hideyuki Hayashi
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Adham Elmously
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Thomas FX O’Donnell
- Division of Vascular Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Virendra Patel
- Division of Vascular Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
| | - Vijay Vedula
- Department of Mechanical Engineering, Columbia University in the City of New York, New York, NY, USA
| | - Hiroo Takayama
- Division of Cardiothoracic Surgery, Department of Surgery, New York-Presbyterian Hospital, Columbia University Medical Center, New York, NY, USA
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Osswald A, Tsagakis K, Demircioglu E, Weymann A, Zubarevich A, Ruhparwar A, Karmonik C. Hostile Hemodynamics in Distal Stent Graft-Induced New Entry Prior to Aortic Rupture: A Comparison of Transient versus Steady-State CFD Simulations. Thorac Cardiovasc Surg 2024; 72:134-141. [PMID: 37506731 DOI: 10.1055/s-0043-1771357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
BACKGROUND Computational fluid dynamics (CFD) simulations model blood flow in aortic pathologies. The aim of our study was to understand the local hemodynamic environment at the site of rupture in distal stent graft-induced new entry (dSINE) after frozen elephant trunk with a clinically time efficient steady-flow simulation versus transient simulations. METHODS Steady-state simulations were performed for dSINE, prior and after its development and prior to aortic rupture. To account for potential turbulences due geometric changes at the dSINE location, Reynolds-averaged Navier-Stokes equations with the realizable k-ε model for turbulences were applied. Transient simulations were performed for comparison. Hemodynamic parameters were assessed at various locations of the aorta. RESULTS Post-dSINE, jet-like flow due to luminal narrowing was observed which increased prior to rupture and resulted in focal neighbored regions of high and low wall shear stress (WSS). Prior to rupture, aortic diameter at the rupture site increased lowering WSS at the entire aortic circumference. Concurrently, WSS and turbulence increased locally above the entry tear at the inner aortic curvature. Turbulent kinetic energy and WSS elevation in the downstream aorta demonstrated enhanced stress on the native aorta. Results of steady-state simulations were in good qualitative agreement with transient simulations. CONCLUSION Steady-flow CFD simulations feasible at clinical time scales prior to aortic rupture reveal a hostile hemodynamic environment at the dSINE rupture site in agreement with lengthy transient simulations. Consequently, our developed approach may be of value in treatment planning where a fast assessment of the local hemodynamic environment is essential.
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Affiliation(s)
- Anja Osswald
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Konstantinos Tsagakis
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Ender Demircioglu
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Alexander Weymann
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Alina Zubarevich
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Arjang Ruhparwar
- Department of Thoracic and Cardiovascular Surgery, West-German Heart and Vascular Center Essen, University Duisburg-Essen, Essen, Germany
| | - Christof Karmonik
- MRI Core, Translational Imaging Center, Houston Methodist Research Institute, Houston, Texas, United States
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Zhu Y, Xu XY, Mason J, Mirsadraee S. Irregular anatomical features can alter hemodynamics in Takayasu arteritis. JVS Vasc Sci 2023; 4:100125. [PMID: 37771369 PMCID: PMC10522970 DOI: 10.1016/j.jvssci.2023.100125] [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: 05/18/2023] [Accepted: 08/08/2023] [Indexed: 09/30/2023] Open
Abstract
Objective Takayasu arteritis (TA) is a difficult disease to deal with because there are neither reliable clinical signs, laboratory biomarkers, nor a single noninvasive imaging technique that can be used for early diagnosis and disease activity monitoring. Knowledge of aortic hemodynamics in TA is lacking. This study aimed to fill this gap by assessing hemodynamics in patients with TA using image-based computational fluid dynamics (CFD) simulations. Methods Eleven patients with TA were included in the present study. Patient-specific geometries were reconstructed from either clinical aortic computed tomography angiography or magnetic resonance angiography studies and coupled with physiological boundary conditions for CFD simulations. Key anatomical and hemodynamic parameters were compared with a control group consisting of 18 age- and sex-matched adults without TA who had healthy aortas. Results Compared with controls, patients with TA had significantly higher aortic velocities (0.9 m/s [0.7, 1.1 m/s] vs 0.6 m/s [0.5, 0.7 m/s]; P = .002), maximum time-averaged wall shear stress (14.2 Pa [9.8, 20.9 Pa] vs 8.0 Pa [6.2, 10.3 Pa]; P = .004), and maximum pressure drops between the ascending and descending aorta (36.9 mm Hg [29.0, 49.3 mm Hg] vs 28.5 mm Hg [25.8, 31.5 mm Hg]; P = .004). These significant hemodynamic alterations in patients with TA might result from abnormal anatomical features including smaller arch diameter (20.0 mm [13.8, 23.3 mm] vs 25.2 mm [23.3, 26.8 mm]; P = .003), supra-aortic branch diameters (21.9 mm [18.5, 24.6 mm] vs 25.7 mm [24.3, 28.3 mm]; P = .003) and descending aorta diameter (14.7 mm [12.2, 16.8 mm] vs 22.5 mm [19.8, 24.0 mm]; P < .001). Conclusions CFD analysis reveals hemodynamic changes in the aorta of patients with TA. The applicability of CFD technique coupled with standard imaging assessments in predicting disease progression of such patients will be explored in future studies. Future large cohort study with outcome correlation is also warranted. Clinical Relevance Based on patient-specific computational fluid dynamics simulations, the present retrospective study revealed significant difference in aortic hemodynamics between the patients with and without Takayasu arteritis (TA). To the best of our knowledge, this study is the first to evaluate hemodynamic conditions within TA, demonstrating the potential of computational flow modeling in capturing abnormal hemodynamic forces, such as high wall shear stress, resulted from irregular morphological changes. In the future, assessing the hemodynamic parameters within patients with TA during the prestenotic period, together with longitudinal computational fluid dynamics studies may allow better monitoring and management of TA.
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Affiliation(s)
- Yu Zhu
- Department of Chemical Engineering, Imperial College London, London, UK
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, UK
| | - Justin Mason
- Rheumatology and Vascular Science, Hammersmith Hospital, Imperial College London, London, UK
| | - Saeed Mirsadraee
- Department of Radiology, Royal Brompton and Harefield Hospitals, London, UK
- National Heart and Lung Institute, Imperial College London, London, UK
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Stokes C, Haupt F, Becker D, Muthurangu V, von Tengg-Kobligk H, Balabani S, Díaz-Zuccarini V. The Influence of Minor Aortic Branches in Patient-Specific Flow Simulations of Type-B Aortic Dissection. Ann Biomed Eng 2023; 51:1627-1644. [PMID: 36967447 PMCID: PMC10264290 DOI: 10.1007/s10439-023-03175-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 02/19/2023] [Indexed: 03/28/2023]
Abstract
Type-B aortic dissection (TBAD) is a disease in which a tear develops in the intimal layer of the descending aorta forming a true lumen and false lumen (FL). Because disease outcomes are thought to be influenced by haemodynamic quantities such as pressure and wall shear stress (WSS), their analysis via numerical simulations may provide valuable clinical insights. Major aortic branches are routinely included in simulations but minor branches are virtually always neglected, despite being implicated in TBAD progression and the development of complications. As minor branches are estimated to carry about 7-21% of cardiac output, neglecting them may affect simulation accuracy. We present the first simulation of TBAD with all pairs of intercostal, subcostal and lumbar arteries, using 4D-flow MRI (4DMR) to inform patient-specific boundary conditions. Compared to an equivalent case without minor branches, their inclusion improved agreement with 4DMR velocities, reduced time-averaged WSS (TAWSS) and transmural pressure and elevated oscillatory shear in regions where FL dilatation and calcification were observed in vivo. Minor branch inclusion resulted in differences of 60-75% in these metrics of potential clinical relevance, indicating a need to account for minor branch flow loss if simulation accuracy is sought.
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Affiliation(s)
- C Stokes
- Department of Mechanical Engineering, University College London, London, UK
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, University College London, London, UK
| | - F Haupt
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, University of Bern, Bern, Switzerland
| | - D Becker
- Clinic of Vascular Surgery, Inselspital, University of Bern, Bern, Switzerland
| | - V Muthurangu
- Centre for Translational Cardiovascular Imaging, University College London, London, UK
| | - H von Tengg-Kobligk
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, University of Bern, Bern, Switzerland
| | - S Balabani
- Department of Mechanical Engineering, University College London, London, UK
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, University College London, London, UK
| | - V Díaz-Zuccarini
- Department of Mechanical Engineering, University College London, London, UK.
- Wellcome-EPSRC Centre for Interventional Surgical Sciences, University College London, London, UK.
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Motoki K, Zhu Y, Mirsadraee S, Rosendahl U, Pepper J, Xu XY. A computational study of the effects of size, location, and number of tears on haemodynamics in surgically repaired type A aortic dissection. Front Cardiovasc Med 2023; 10:1215720. [PMID: 37388636 PMCID: PMC10301719 DOI: 10.3389/fcvm.2023.1215720] [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: 05/02/2023] [Accepted: 06/05/2023] [Indexed: 07/01/2023] Open
Abstract
Objective This study aimed to comprehensively examine the roles of size, location, and number of tears in the progression of surgically repaired type A aortic dissection (TAAD) by assessing haemodynamic changes through patient-specific computational fluid dynamic (CFD) simulations. Methods Two patient-specific TAAD geometries with replaced ascending aorta were reconstructed based upon computed 15 tomography (CT) scans, after which 10 hypothetical models (5 per patient) with different tear configurations were artificially created. CFD simulations were performed on all the models under physiologically realistic boundary conditions. Results Our simulation results showed that increasing either the size or number of the re-entry tears reduced the luminal pressure difference (LPD) and maximum time-averaged wall shear stress (TAWSS), as well as areas exposed to abnormally high or low TAWSS values. Models with a large re-entry tear outperformed the others by reducing the maximum LPD by 1.88 mmHg and 7.39 mmHg, for patients 1 and 2, respectively. Moreover, proximally located re-entry tears in the descending aorta were more effective at reducing LPD than distal re-entry tears. Discussion These computational results indicate that the presence of a relatively large re-entry tear in the proximal descending aorta might help stabilize post-surgery aortic growth. This finding has important implications for the management and risk stratification of surgically repaired TAAD patients. Nevertheless, further validation in a large patient cohort is needed.
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Affiliation(s)
- Kyosuke Motoki
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
| | - Yu Zhu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
| | - Saeed Mirsadraee
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Radiology, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - Ulrich Rosendahl
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - John Pepper
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
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Zhu Y, Xu XY, Rosendahl U, Pepper J, Mirsadraee S. Advanced risk prediction for aortic dissection patients using imaging-based computational flow analysis. Clin Radiol 2023; 78:e155-e165. [PMID: 36610929 DOI: 10.1016/j.crad.2022.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/28/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022]
Abstract
Patients with either a repaired or medically managed aortic dissection have varying degrees of risk of developing late complications. High-risk patients would benefit from earlier intervention to improve their long-term survival. Currently serial imaging is used for risk stratification, which is not always reliable. On the other hand, understanding aortic haemodynamics within a dissection is essential to fully evaluate the disease and predict how it may progress. In recent decades, computational fluid dynamics (CFD) has been extensively applied to simulate complex haemodynamics within aortic diseases, and more recently, four-dimensional (4D)-flow magnetic resonance imaging (MRI) techniques have been developed for in vivo haemodynamic measurement. This paper presents a comprehensive review on the application of image-based CFD simulations and 4D-flow MRI analysis for risk prediction in aortic dissection. The key steps involved in patient-specific CFD analyses are demonstrated. Finally, we propose a workflow incorporating computational modelling for personalised assessment to aid in risk stratification and treatment decision-making.
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Affiliation(s)
- Y Zhu
- Department of Chemical Engineering, Imperial College London, London, UK
| | - X Y Xu
- Department of Chemical Engineering, Imperial College London, London, UK
| | - U Rosendahl
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, UK; National Heart and Lung Institute, Imperial College London, London, UK
| | - J Pepper
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, UK; National Heart and Lung Institute, Imperial College London, London, UK
| | - S Mirsadraee
- National Heart and Lung Institute, Imperial College London, London, UK; Department of Radiology, Royal Brompton and Harefield Hospitals, London, UK.
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Gaudry M, Guivier-Curien C, Blanchard A, Porto A, Bal L, Omnes V, De Masi M, Lu C, Jacquier A, Piquet P, Deplano V. Volume Analysis to Predict the Long-Term Evolution of Residual Aortic Dissection after Type A Repair. J Cardiovasc Dev Dis 2022; 9:jcdd9100349. [PMID: 36286301 PMCID: PMC9604488 DOI: 10.3390/jcdd9100349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/26/2022] [Accepted: 10/08/2022] [Indexed: 11/05/2022] Open
Abstract
Background: The aim of this study was to evaluate the aortic diameter and volume during the first year after a type A repair to predict the long-term prognosis of a residual aortic dissection (RAD). Methods: All patients treated in our center for an acute type A dissection with a RAD and follow-up > 3 years were included. We defined two groups: group 1 with dissection-related events (defined as an aneurysmal evolution, distal reintervention, or aortic-related death) and group 2 without dissection-related events. The aortic diameters and volume analysis were evaluated on three postoperative CT scans: pre-discharge (T1), 3−6 months (T2) and 1 year (T3). Results: Between 2009 and 2016, 54 patients were included. Following a mean follow-up of 75.4 months (SD 31.5), the rate of dissection-related events was 62.9% (34/54). The total aortic diameters of the descending thoracic aorta were greater in group 1 at T1, T2 and T3, with greater diameters in the FL (p < 0.01). The aortic diameter evolution at 3 months was not predictive of long-term dissection-related events. The total thoracic aortic volume was significantly greater in group 1 at T1 (p < 0.01), T2 (p < 0.01), and T3 (p < 0.01). At 3 months, the increase in the FL volume was significantly greater in group 1 (p < 0.01) and was predictive for long-term dissection-related events. Conclusion: This study shows that an initial CT scan volume analysis coupled with another at 3 months is predictive for the long-term evolution in a RAD. Based on this finding, more aggressive treatment could be given at an earlier stage.
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Affiliation(s)
- Marine Gaudry
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
- Correspondence: ; Tel.: +33-491-388-120
| | | | - Arnaud Blanchard
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Alizée Porto
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
- Department of Cardiac Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Laurence Bal
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Virgile Omnes
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Mariangela De Masi
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Charlotte Lu
- Department of Radiology, APHM, Timone Hospital, 13005 Marseille, France
| | - Alexis Jacquier
- Department of Radiology, APHM, Timone Hospital, 13005 Marseille, France
| | - Philippe Piquet
- Timone Aortic Center, Department of Vascular Surgery, APHM, Timone Hospital, 13005 Marseille, France
| | - Valerie Deplano
- CNRS, Centrale Marseille, IRPHE, Aix Marseille University, 13013 Marseille, France
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Zhu Y, Mirsadraee S, Rosendahl U, Pepper J, Xu XY. Fluid-Structure Interaction Simulations of Repaired Type A Aortic Dissection: a Comprehensive Comparison With Rigid Wall Models. Front Physiol 2022; 13:913457. [PMID: 35774287 PMCID: PMC9237394 DOI: 10.3389/fphys.2022.913457] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 05/17/2022] [Indexed: 11/26/2022] Open
Abstract
This study aimed to evaluate the effect of aortic wall compliance on intraluminal hemodynamics within surgically repaired type A aortic dissection (TAAD). Fully coupled two-way fluid-structure interaction (FSI) simulations were performed on two patient-specific post-surgery TAAD models reconstructed from computed tomography angiography images. Our FSI model incorporated prestress and different material properties for the aorta and graft. Computational results, including velocity, wall shear stress (WSS) and pressure difference between the true and false lumen, were compared between the FSI and rigid wall simulations. It was found that the FSI model predicted lower blood velocities and WSS along the dissected aorta. In particular, the area exposed to low time-averaged WSS (≤0.2 Pa) was increased from 21 cm2 (rigid) to 38 cm2 (FSI) in patient 1 and from 35 cm2 (rigid) to 144 cm2 (FSI) in patient 2. FSI models also produced more disturbed flow where much larger regions presented with higher turbulence intensity as compared to the rigid wall models. The effect of wall compliance on pressure difference between the true and false lumen was insignificant, with the maximum difference between FSI and rigid models being less than 0.25 mmHg for the two patient-specific models. Comparisons of simulation results for models with different Young’s moduli revealed that a more compliant wall resulted in further reduction in velocity and WSS magnitudes because of increased displacements. This study demonstrated the importance of FSI simulation for accurate prediction of low WSS regions in surgically repaired TAAD, but a rigid wall computational fluid dynamics simulation would be sufficient for prediction of luminal pressure difference.
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Affiliation(s)
- Yu Zhu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
| | - Saeed Mirsadraee
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Radiology, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - Ulrich Rosendahl
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - John Pepper
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Cardiac Surgery, Royal Brompton and Harefield Hospitals, London, United Kingdom
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, United Kingdom
- *Correspondence: Xiao Yun Xu,
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