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Ramaekers MJFG, Te Kiefte BJC, Adriaans BP, Juffermans JF, van Assen HC, Winkens B, Wildberger JE, Lamb HJ, Schalla S, Westenberg JJM. Comprehensive sex-specific and age-dependent analysis of 4D-flow MRI assessed aortic blood flow-related parameters in normal subjects using single-vendor MR systems and single-vendor software. J Cardiovasc Magn Reson 2024:101083. [PMID: 39142568 DOI: 10.1016/j.jocmr.2024.101083] [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: 11/14/2023] [Revised: 06/14/2024] [Accepted: 08/08/2024] [Indexed: 08/16/2024] Open
Abstract
BACKGROUND Aortic blood flow characterization by 4D flow MRI is increasingly performed in aneurysm research. A limited number of studies have established normal values that can aid the recognition of abnormal flow at an early stage. This study aims to establish additional sex-specific and age-dependent reference values for flow-related parameters in a large cohort of healthy adults. METHODS 212 volunteers were included, and 191 volunteers completed the full study protocol. All underwent 4D flow MRI of the entire aorta. Quantitative values for velocity, vorticity, helicity, as well as total, circumferential, and axial wall shear stress [WSS] were determined for the aortic root [AoR], ascending aorta [AAo], aortic arch [AoA], descending [DAo], suprarenal [SRA], and infrarenal aorta [IRA]. Vorticity and helicity were indexed for segment volume (mL). RESULTS The normal values were estimated per sex- and age-group, where significant differences between males (M) and females (F) were found only for specific age groups. More specifically, the following variables were significantly different after applying the false discovery rate correction for multiple testing: 1) velocity in the AAo and DAo in the 60-70 years age group (mean±SD: (M) 47.0 ± 8.2cm/s vs. (F) 38.4 ± 6.9cm/s, p=0.001 and, (M) 55.9 ± 9.9cm/s vs. (F) 46.5 ± 5.5cm/s, p=0.002), 2) normalized vorticity in AoR in the 50-59 years age group ((M) 27539 ± 5042s-1mL-1 vs. (F) 30849 ± 7285s-1mL-1, p=0.002), 3) axial WSS in the Aao in the 18-29 age group ((M) 1098 ± 203 mPa vs. (F) 921 ± 121 mPa, p=0.002). Good to strong negative correlations with age were seen for almost all variables, in different segments, and for both sexes. CONCLUSION This study describes reference values for aortic flow-related parameters as acquired by 4D flow MRI. We observed limited differences between males and females. A negative relationship with age was seen for almost all flow-related parameters and segments.
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Affiliation(s)
- Mitch J F G Ramaekers
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Department of Cardiology, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands.
| | - Bastiaan J C Te Kiefte
- Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Bouke P Adriaans
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Department of Cardiology, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Joe F Juffermans
- Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Hans C van Assen
- Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Bjorn Winkens
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; Care and Public Health Research Institute (CAPHRI), Maastricht University, Maastricht, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Joachim E Wildberger
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Hildo J Lamb
- Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Simon Schalla
- Department of Cardiology, Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands; Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
| | - Jos J M Westenberg
- Department of Radiology, Leiden University Medical Center (LUMC), Leiden, the Netherlands; Department of Methodology and Statistics, Maastricht University, Maastricht, the Netherlands
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Martier A, Chen Z, Schaps H, Mondrinos MJ, Fang JS. Capturing physiological hemodynamic flow and mechanosensitive cell signaling in vessel-on-a-chip platforms. Front Physiol 2024; 15:1425618. [PMID: 39135710 PMCID: PMC11317428 DOI: 10.3389/fphys.2024.1425618] [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: 05/06/2024] [Accepted: 07/10/2024] [Indexed: 08/15/2024] Open
Abstract
Recent advances in organ chip (or, "organ-on-a-chip") technologies and microphysiological systems (MPS) have enabled in vitro investigation of endothelial cell function in biomimetic three-dimensional environments under controlled fluid flow conditions. Many current organ chip models include a vascular compartment; however, the design and implementation of these vessel-on-a-chip components varies, with consequently varied impact on their ability to capture and reproduce hemodynamic flow and associated mechanosensitive signaling that regulates key characteristics of healthy, intact vasculature. In this review, we introduce organ chip and vessel-on-a-chip technology in the context of existing in vitro and in vivo vascular models. We then briefly discuss the importance of mechanosensitive signaling for vascular development and function, with focus on the major mechanosensitive signaling pathways involved. Next, we summarize recent advances in MPS and organ chips with an integrated vascular component, with an emphasis on comparing both the biomimicry and adaptability of the diverse approaches used for supporting and integrating intravascular flow. We review current data showing how intravascular flow and fluid shear stress impacts vessel development and function in MPS platforms and relate this to existing work in cell culture and animal models. Lastly, we highlight new insights obtained from MPS and organ chip models of mechanosensitive signaling in endothelial cells, and how this contributes to a deeper understanding of vessel growth and function in vivo. We expect this review will be of broad interest to vascular biologists, physiologists, and cardiovascular physicians as an introduction to organ chip platforms that can serve as viable model systems for investigating mechanosensitive signaling and other aspects of vascular physiology.
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Affiliation(s)
- A. Martier
- Department of Biomedical Engineering, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - Z. Chen
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - H. Schaps
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
| | - M. J. Mondrinos
- Department of Biomedical Engineering, School of Science and Engineering, Tulane University, New Orleans, LA, United States
- Department of Physiology, School of Medicine, Tulane University, New Orleans, LA, United States
| | - J. S. Fang
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA, United States
- Department of Physiology, School of Medicine, Tulane University, New Orleans, LA, United States
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Asciak L, Domingo-Roca R, Dow JR, Brodie R, Paterson N, Riches PE, Shu W, McCormick C. Exploiting light-based 3D-printing for the fabrication of mechanically enhanced, patient-specific aortic grafts. J Mech Behav Biomed Mater 2024; 154:106531. [PMID: 38588633 DOI: 10.1016/j.jmbbm.2024.106531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/10/2024]
Abstract
Despite polyester vascular grafts being routinely used in life-saving aortic aneurysm surgeries, they are less compliant than the healthy, native human aorta. This mismatch in mechanical behaviour has been associated with disruption of haemodynamics contributing to several long-term cardiovascular complications. Moreover, current fabrication approaches mean that opportunities to personalise grafts to the individual anatomical features are limited. Various modifications to graft design have been investigated to overcome such limitations; yet optimal graft functionality remains to be achieved. This study reports on the development and characterisation of an alternative vascular graft material. An alginate:PEGDA (AL:PE) interpenetrating polymer network (IPN) hydrogel has been produced with uniaxial tensile tests revealing similar strength and stiffness (0.39 ± 0.05 MPa and 1.61 ± 0.19 MPa, respectively) to the human aorta. Moreover, AL:PE tubular conduits of similar geometrical dimensions to segments of the aorta were produced, either via conventional moulding methods or stereolithography (SLA) 3D-printing. While both fabrication methods successfully demonstrated AL:PE hydrogel production, SLA 3D-printing was more easily adaptable to the fabrication of complex structures without the need of specific moulds or further post-processing. Additionally, most 3D-printed AL:PE hydrogel tubular conduits sustained, without failure, compression up to 50% their outer diameter and returned to their original shape upon load removal, thereby exhibiting promising behaviour that could withstand pulsatile pressure in vivo. Overall, these results suggest that this AL:PE IPN hydrogel formulation in combination with 3D-printing, has great potential for accelerating progress towards personalised and mechanically-matched aortic grafts.
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Affiliation(s)
- Lisa Asciak
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - Roger Domingo-Roca
- Department of Electronic and Electric Engineering, University of Strathclyde, Glasgow, UK
| | - Jamie R Dow
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK; Research and Development, Terumo Aortic Ltd., Inchinnan, Glasgow, UK
| | - Robbie Brodie
- Research and Development, Terumo Aortic Ltd., Inchinnan, Glasgow, UK
| | - Niall Paterson
- Research and Development, Terumo Aortic Ltd., Inchinnan, Glasgow, UK
| | - Philip E Riches
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
| | - Wenmiao Shu
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK
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Baek KI, Ryu K. Role of Flow-Sensitive Endothelial Genes in Atherosclerosis and Antiatherogenic Therapeutics Development. J Cardiovasc Transl Res 2024; 17:609-623. [PMID: 38010480 DOI: 10.1007/s12265-023-10463-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 11/14/2023] [Indexed: 11/29/2023]
Abstract
Atherosclerosis is a chronic inflammatory disease that is the underlying cause of cardiovascular disease which initiates from endothelial dysfunction from genetic and environmental risk factors, including biomechanical forces: blood flow. Endothelial cells (ECs) lining the inner arterial wall regions exposed to disturbed flow are prone to atherosclerosis development, whereas the straight regions exposed to stable flow are spared from the disease. These flow patterns induce genome- and epigenome-wide changes in gene expression in ECs. Through the sweeping changes in gene expression, disturbed flow reprograms ECs from athero-protected cell types under the stable flow condition to pro-atherogenic cell conditions. The pro-atherogenic changes induced by disturbed flow, in combination with additional risk factors such as hypercholesterolemia, lead to the progression of atherosclerosis. The flow-sensitive genes and proteins are critical in understanding the mechanisms and serve as novel targets for antiatherogenic therapeutics.
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Affiliation(s)
- Kyung In Baek
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Kitae Ryu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
- Department of Biotechnology, The University of Suwon, 17, Wauan-Gil, Bongdam-Eup, Hwaseong-Si, Gyeonggi-Do, 18323, Republic of Korea.
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Pham MHC, Sigvardsen PE, Fuchs A, Kühl JT, Sillesen H, Afzal S, Nordestgaard BG, Køber LV, Kofoed KF. Aortic aneurysms in a general population cohort: prevalence and risk factors in men and women. Eur Heart J Cardiovasc Imaging 2024:jeae103. [PMID: 38662458 DOI: 10.1093/ehjci/jeae103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 04/08/2024] [Accepted: 04/13/2024] [Indexed: 08/18/2024] Open
Abstract
BACKGROUND AND AIMS The prevalence and difference in risk factors for having thoracic and abdominal aortic aneurysms in men compared to women in the general population is not well-described. This study aimed to test the hypotheses i) that cardiovascular risk factors for thoracic and abdominal aortic aneurysms differ and ii) that the prevalence of thoracic and abdominal aortic aneurysms is sex specific. METHODS Aortic examination using computed tomography angiography was performed in 11,294 individuals (56% women), with a mean age of 62 [range 40-95] years participating in the Copenhagen General Population Study. Thoracic aortic aneurysms were defined as ascending aortic diameter ≥45 mm and descending aortic diameter ≥35 mm, abdominal aortic aneurysms were defined as abdominal aortic diameter ≥30 mm. Demographic data were obtained from questionnaires. RESULTS Overall prevalence of aortic aneurysms in the study population included: total population 2.1%, men 4.0% and women 0.7% (p-test men vs. women p<0.001). Aortic aneurysms were independently associated with male sex, increasing age, and body surface area. While thoracic aortic aneurysms were associated with hypertension, odds ratio=2.0[95%CI:1.5-2.8], abdominal aortic aneurysms were associated with hypercholesterolemia and smoking, odds ratios=2.4[95%CI:1.6-3.6] and 3.2[95%CI:1.9-5.4]. CONCLUSIONS Subclinical aortic aneurysms are four times more prevalent in men than women. In both sexes, increasing age and body surface area are risk factors for aortic aneurysms of any anatomical location. Whereas arterial hypertension is a risk factor for thoracic aortic aneurysms, hypercholesterolemia and smoking are risk factors for abdominal aortic aneurysms.
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Affiliation(s)
- Michael Huy Cuong Pham
- Department of Cardiology, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Radiology, The Diagnostic Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Per Ejlstrup Sigvardsen
- Department of Cardiology, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Radiology, The Diagnostic Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Andreas Fuchs
- Department of Cardiology, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Radiology, The Diagnostic Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | | | - Henrik Sillesen
- Department of Vascular Surgery, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Shoaib Afzal
- Department of Clinical Biochemistry, Copenhagen University Hospital - Herlev and Gentofte Hospital, Copenhagen, Denmark
- Copenhagen General Population Study, Copenhagen University Hospital - Herlev and Gentofte Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Børge Grønne Nordestgaard
- Department of Clinical Biochemistry, Copenhagen University Hospital - Herlev and Gentofte Hospital, Copenhagen, Denmark
- Copenhagen General Population Study, Copenhagen University Hospital - Herlev and Gentofte Hospital, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Valeur Køber
- Department of Cardiology, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Klaus Fuglsang Kofoed
- Department of Cardiology, The Heart Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Radiology, The Diagnostic Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Aslan S, Liu X, Wu Q, Mass P, Loke YH, Johnson J, Huddle J, Olivieri L, Hibino N, Krieger A. Virtual Planning and Patient-Specific Graft Design for Aortic Repairs. Cardiovasc Eng Technol 2024; 15:123-136. [PMID: 37985613 DOI: 10.1007/s13239-023-00701-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 11/07/2023] [Indexed: 11/22/2023]
Abstract
PURPOSE Patients presenting with coarctation of the aorta (CoA) may also suffer from co-existing transverse arch hypoplasia (TAH). Depending on the risks associated with the surgery and the severity of TAH, clinicians may decide to repair only CoA, and monitor the TAH to see if it improves as the patient grows. While acutely successful, eventually hemodynamics may become suboptimal if TAH is left untreated. The objective of this work aims to develop a patient-specific surgical planning framework for predicting and assessing postoperative outcomes of simple CoA repair and comprehensive repair of CoA and TAH. METHODS The surgical planning framework consisted of virtual clamp placement, stenosis resection, and design and optimization of patient-specific aortic grafts that involved geometrical modeling of the graft and computational fluid dynamics (CFD) simulation for evaluating various surgical plans. Time-dependent CFD simulations were performed using Windkessel boundary conditions at the outlets that were obtained from patient-specific non-invasive pressure and flow data to predict hemodynamics before and after the virtual repairs. We applied the proposed framework to investigate optimal repairs for six patients (n = 6) diagnosed with both CoA and TAH. Design optimization was performed by creating a combination of a tubular graft and a waterslide patch to reconstruct the aortic arch. The surfaces of the designed graft were parameterized to optimize the shape. RESULTS Peak systolic pressure drop (PSPD) and time-averaged wall shear stress (TAWSS) were used as performance metrics to evaluate surgical outcomes of various graft designs and implantation. The average PSPD improvements were 28% and 44% after the isolated CoA repair and comprehensive repair, respectively. Maximum values of TAWSS were decreased by 60% after CoA repair and further improved by 22% after the comprehensive repair. The oscillatory shear index was calculated and the values were confirmed to be in the normal range after the repairs. CONCLUSION The results showed that the comprehensive repair outperforms the simple CoA repair and may be more advantageous in the long term in some patients. We demonstrated that the surgical planning and patient-specific flow simulations could potentially affect the selection and outcomes of aorta repairs.
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Affiliation(s)
- Seda Aslan
- Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA.
| | - Xiaolong Liu
- Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
- Department of Mechanical Engineering, Texas Tech University, Lubbock, TX, USA
| | - Qiyuan Wu
- Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
| | - Paige Mass
- Division of Cardiology, Children's National Hospital, Washington, DC, USA
| | - Yue-Hin Loke
- Division of Cardiology, Children's National Hospital, Washington, DC, USA
| | | | | | - Laura Olivieri
- Division of Cardiology, Children's National Hospital, Washington, DC, USA
| | - Narutoshi Hibino
- Section of Cardiac Surgery, Department of Surgery, The University of Chicago Medicine, Chicago, IL, USA
| | - Axel Krieger
- Department of Mechanical Engineering, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA
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Laha S, Fourtakas G, Das PK, Keshmiri A. Smoothed particle hydrodynamics based FSI simulation of the native and mechanical heart valves in a patient-specific aortic model. Sci Rep 2024; 14:6762. [PMID: 38514703 PMCID: PMC10957961 DOI: 10.1038/s41598-024-57177-w] [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: 01/09/2024] [Accepted: 03/14/2024] [Indexed: 03/23/2024] Open
Abstract
The failure of the aortic heart valve is common, resulting in deterioration of the pumping function of the heart. For the end stage valve failure, bi-leaflet mechanical valve (most popular artificial valve) is implanted. However, due to its non-physiological behaviour, a significant alteration is observed in the normal haemodynamics of the aorta. While in-vivo experimentation of a human heart valve (native and artificial) is a formidable task, in-silico study using computational fluid dynamics (CFD) with fluid structure interaction (FSI) is an effective and economic tool for investigating the haemodynamics of natural and artificial heart valves. In the present work, a haemodynamic model of a natural and mechanical heart valve has been developed using meshless particle-based smoothed particle hydrodynamics (SPH). In order to further enhance its clinical relevance, this study employs a patient-specific vascular geometry and presents a successful validation against traditional finite volume method and 4D magnetic resonance imaging (MRI) data. The results have demonstrated that SPH is ideally suited to simulate the heart valve function due to its Lagrangian description of motion, which is a favourable feature for FSI. In addition, a novel methodology for the estimation of the wall shear stress (WSS) and other related haemodynamic parameters have been proposed from the SPH perspective. Finally, a detailed comparison of the haemodynamic parameters has been carried out for both native and mechanical aortic valve, with a particular emphasis on the clinical risks associated with the mechanical valve.
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Affiliation(s)
- Sumanta Laha
- School of Engineering, University of Manchester, Manchester, M13 9PL, UK
- Department of Mechanical Engineering, IIT Kharagpur, Kharagpur, 721302, India
| | - Georgios Fourtakas
- School of Engineering, University of Manchester, Manchester, M13 9PL, UK
| | - Prasanta K Das
- Department of Mechanical Engineering, IIT Kharagpur, Kharagpur, 721302, India
| | - Amir Keshmiri
- School of Engineering, University of Manchester, Manchester, M13 9PL, UK.
- Manchester University NHS Foundation Trust, Manchester, M13 9PL, UK.
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Bouaou K, Dietenbeck T, Soulat G, Bargiotas I, Houriez-Gombaud-Saintonge S, De Cesare A, Gencer U, Giron A, Jiménez E, Messas E, Lucor D, Bollache E, Mousseaux E, Kachenoura N. Four-dimensional flow cardiovascular magnetic resonance aortic cross-sectional pressure changes and their associations with flow patterns in health and ascending thoracic aortic aneurysm. J Cardiovasc Magn Reson 2024; 26:101030. [PMID: 38403074 PMCID: PMC10950879 DOI: 10.1016/j.jocmr.2024.101030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/20/2024] [Indexed: 02/27/2024] Open
Abstract
BACKGROUND Ascending thoracic aortic aneurysm (ATAA) is a silent and threatening dilation of the ascending aorta (AscAo). Maximal aortic diameter which is currently used for ATAA patients management and surgery planning has been shown to inadequately characterize risk of dissection in a large proportion of patients. Our aim was to propose a comprehensive quantitative evaluation of aortic morphology and pressure-flow-wall associations from four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) data in healthy aging and in patients with ATAA. METHODS We studied 17 ATAA patients (64.7 ± 14.3 years, 5 females) along with 17 age- and sex-matched healthy controls (59.7 ± 13.3 years, 5 females) and 13 younger healthy subjects (33.5 ± 11.1 years, 4 females). All subjects underwent a CMR exam, including 4D flow and three-dimensional anatomical images of the aorta. This latter dataset was used for aortic morphology measurements, including AscAo maximal diameter (iDMAX) and volume, indexed to body surface area. 4D flow MRI data were used to estimate 1) cross-sectional local AscAo spatial (∆PS) and temporal (∆PT) pressure changes as well as the distance (∆DPS) and time duration (∆TPT) between local pressure peaks, 2) AscAo maximal wall shear stress (WSSMAX) at peak systole, and 3) AscAo flow vorticity amplitude (VMAX), duration (VFWHM), and eccentricity (VECC). RESULTS Consistency of flow and pressure indices was demonstrated through their significant associations with AscAo iDMAX (WSSMAX:r = -0.49, p < 0.001; VECC:r = -0.29, p = 0.045; VFWHM:r = 0.48, p < 0.001; ∆DPS:r = 0.37, p = 0.010; ∆TPT:r = -0.52, p < 0.001) and indexed volume (WSSMAX:r = -0.63, VECC:r = -0.51, VFWHM:r = 0.53, ∆DPS:r = 0.54, ∆TPT:r = -0.63, p < 0.001 for all). Intra-AscAo cross-sectional pressure difference, ∆PS, was significantly and positively associated with both VMAX (r = 0.55, p = 0.002) and WSSMAX (r = 0.59, p < 0.001) in the 30 healthy subjects (48.3 ± 18.0 years). Associations remained significant after adjustment for iDMAX, age, and systolic blood pressure. Superimposition of ATAA patients to normal aging trends between ∆PS and WSSMAX as well as VMAX allowed identifying patients with substantially high pressure differences concomitant with AscAo dilation. CONCLUSION Local variations in pressures within ascending aortic cross-sections derived from 4D flow MRI were associated with flow changes, as quantified by vorticity, and with stress exerted by blood on the aortic wall, as quantified by wall shear stress. Such flow-wall and pressure interactions might help for the identification of at-risk patients.
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Affiliation(s)
- Kevin Bouaou
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Thomas Dietenbeck
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Gilles Soulat
- Hôpital Européen Georges Pompidou, INSERM 970, Paris, France.
| | - Ioannis Bargiotas
- CMLA, ENS Cachan, CNRS, Université Paris-Saclay, 94235 Cachan, France.
| | | | - Alain De Cesare
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Umit Gencer
- Hôpital Européen Georges Pompidou, INSERM 970, Paris, France.
| | - Alain Giron
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Elena Jiménez
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Emmanuel Messas
- Hôpital Européen Georges Pompidou, INSERM 970, Paris, France.
| | - Didier Lucor
- Université Paris-Saclay, CNRS, Laboratoire Interdisciplinaire des Sciences du Numérique, Orsay, France.
| | - Emilie Bollache
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
| | - Elie Mousseaux
- Hôpital Européen Georges Pompidou, INSERM 970, Paris, France.
| | - Nadjia Kachenoura
- Sorbonne Université, INSERM, CNRS, Laboratoire d'Imagerie Biomédicale, Paris, France.
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Versnjak J, Yevtushenko P, Kuehne T, Bruening J, Goubergrits L. Deep learning based assessment of hemodynamics in the coarctation of the aorta: comparison of bidirectional recurrent and convolutional neural networks. Front Physiol 2024; 15:1288339. [PMID: 38449784 PMCID: PMC10916009 DOI: 10.3389/fphys.2024.1288339] [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: 09/04/2023] [Accepted: 01/24/2024] [Indexed: 03/08/2024] Open
Abstract
The utilization of numerical methods, such as computational fluid dynamics (CFD), has been widely established for modeling patient-specific hemodynamics based on medical imaging data. Hemodynamics assessment plays a crucial role in treatment decisions for the coarctation of the aorta (CoA), a congenital heart disease, with the pressure drop (PD) being a crucial biomarker for CoA treatment decisions. However, implementing CFD methods in the clinical environment remains challenging due to their computational cost and the requirement for expert knowledge. This study proposes a deep learning approach to mitigate the computational need and produce fast results. Building upon a previous proof-of-concept study, we compared the effects of two different artificial neural network (ANN) architectures trained on data with different dimensionalities, both capable of predicting hemodynamic parameters in CoA patients: a one-dimensional bidirectional recurrent neural network (1D BRNN) and a three-dimensional convolutional neural network (3D CNN). The performance was evaluated by median point-wise root mean square error (RMSE) for pressures along the centerline in 18 test cases, which were not included in a training cohort. We found that the 3D CNN (median RMSE of 3.23 mmHg) outperforms the 1D BRNN (median RMSE of 4.25 mmHg). In contrast, the 1D BRNN is more precise in PD prediction, with a lower standard deviation of the error (±7.03 mmHg) compared to the 3D CNN (±8.91 mmHg). The differences between both ANNs are not statistically significant, suggesting that compressing the 3D aorta hemodynamics into a 1D centerline representation does not result in the loss of valuable information when training ANN models. Additionally, we evaluated the utility of the synthetic geometries of the aortas with CoA generated by using a statistical shape model (SSM), as well as the impact of aortic arch geometry (gothic arch shape) on the model's training. The results show that incorporating a synthetic cohort obtained through the SSM of the clinical cohort does not significantly increase the model's accuracy, indicating that the synthetic cohort generation might be oversimplified. Furthermore, our study reveals that selecting training cases based on aortic arch shape (gothic versus non-gothic) does not improve ANN performance for test cases sharing the same shape.
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Affiliation(s)
| | | | | | | | - Leonid Goubergrits
- Institute of Computer-assisted Cardiovascular Medicine, Deutsches Herzzentrum der Charité, Berlin, Germany
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10
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Pirola S, Pirola S, Mastroiacovo G, Bonomi A, Manchester EL, Fisichella SM, Maragna R, Baggiano A, Mushtaq S, Muscogiuri G, Guglielmo M, Yun Xu X, Pontone G, Polvani G. Does the AVNeo valve reduce wall stress on the aortic wall? A cardiac magnetic resonance analysis with 4D-flow for the evaluation of aortic valve replacement with the Ozaki technique. Eur J Cardiothorac Surg 2023; 64:ezad299. [PMID: 37656941 DOI: 10.1093/ejcts/ezad299] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 08/15/2023] [Accepted: 08/31/2023] [Indexed: 09/03/2023] Open
Abstract
OBJECTIVES Aortic valve neocuspidalization aims to replace the 3 aortic cusps with autologous pericardium pre-treated with glutaraldehyde, and it is a surgical alternative to the classical aortic valve replacement (AVR). Image-based patient-specific computational fluid dynamics allows the derivation of shear stress on the aortic wall [wall shear stress (WSS)]. Previous studies support a potential link between increased WSS and histological alterations of the aortic wall. The aim of this study is to compare the WSS of the ascending aorta in patients undergoing aortic valve neocuspidalization versus AVR with biological prostheses. METHODS This is a prospective nonrandomized clinical trial. Each patient underwent a 4D-flow cardiac magnetic resonance scan after surgery, which informed patient-specific computational fluid dynamics models to evaluate WSS at the ascending aortic wall. The adjusted variables were calculated by summing the residuals obtained from a multivariate linear model (with ejection fraction and left ventricle outflow tract-aorta angle as covariates) to the mean of the variables. RESULTS Ten patients treated with aortic valve neocuspidalization were enrolled and compared with 10 AVR patients. The aortic valve neocuspidalization group showed a significantly lower WSS in the outer curvature segments of the proximal and distal ascending aorta as compared to AVR patients (P = 0.0179 and 0.0412, respectively). WSS levels remained significantly lower along the outer curvature of the proximal aorta in the aortic valve neocuspidalization population, even after adjusting the WSS for the ejection fraction and the left ventricle outflow tract-aorta angle [2.44 Pa (2.17-3.01) vs 1.94 Pa (1.72-2.01), P = 0.02]. CONCLUSIONS Aortic valve neocuspidalization hemodynamical features are potentially associated with a lower WSS in the ascending aorta as compared to commercially available bioprosthetic valves.
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Affiliation(s)
- Sergio Pirola
- Department of Cardiovascular Surgery, IRCCS Centro Cardiologico Monzino, Milan, Italy
| | - Selene Pirola
- Institute of Clinical Sciences, Imperial College London, London, UK
- Department of BioMechanical Engineering, TU Delft, Delft, Netherlands
| | - Giorgio Mastroiacovo
- Department of Cardiovascular Surgery, IRCCS Centro Cardiologico Monzino, Milan, Italy
| | - Alice Bonomi
- Department of Biostatistics, IRCCS Centro Cardiologico Monzino, Milan, Italy
| | | | | | - Riccardo Maragna
- Department of Cardiac imaging, IRCCS Centro Cardiologico Monzino, Milan, Italy
| | - Andrea Baggiano
- Department of Cardiac imaging, IRCCS Centro Cardiologico Monzino, Milan, Italy
- Department of Cardiovascular Sciences and Community Health, University of Milan, Milan, Italy
| | | | - Giuseppe Muscogiuri
- Department of Radiology, IRCCS Istituto Auxologico Italiano, San Luca Hospital, Milan, Italy
| | - Marco Guglielmo
- Department of Cardiology, Division of Heart and Lungs, Utrecht University, Utrecht University Medical Center, Utrecht, Netherlands
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, UK
| | - Gianluca Pontone
- Department of Cardiac imaging, IRCCS Centro Cardiologico Monzino, Milan, Italy
| | - Gianluca Polvani
- Department of Cardiovascular Surgery, IRCCS Centro Cardiologico Monzino, Milan, Italy
- Department of Surgical and Dental Biomedical Sciences, University of Milan, Italy
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11
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Black SM, Maclean C, Barrientos PH, Ritos K, Kazakidi A. Reconstruction and Validation of Arterial Geometries for Computational Fluid Dynamics Using Multiple Temporal Frames of 4D Flow-MRI Magnitude Images. Cardiovasc Eng Technol 2023; 14:655-676. [PMID: 37653353 PMCID: PMC10602980 DOI: 10.1007/s13239-023-00679-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/08/2023] [Indexed: 09/02/2023]
Abstract
PURPOSE Segmentation and reconstruction of arterial blood vessels is a fundamental step in the translation of computational fluid dynamics (CFD) to the clinical practice. Four-dimensional flow magnetic resonance imaging (4D Flow-MRI) can provide detailed information of blood flow but processing this information to elucidate the underlying anatomical structures is challenging. In this study, we present a novel approach to create high-contrast anatomical images from retrospective 4D Flow-MRI data. METHODS For healthy and clinical cases, the 3D instantaneous velocities at multiple cardiac time steps were superimposed directly onto the 4D Flow-MRI magnitude images and combined into a single composite frame. This new Composite Phase-Contrast Magnetic Resonance Angiogram (CPC-MRA) resulted in enhanced and uniform contrast within the lumen. These images were subsequently segmented and reconstructed to generate 3D arterial models for CFD. Using the time-dependent, 3D incompressible Reynolds-averaged Navier-Stokes equations, the transient aortic haemodynamics was computed within a rigid wall model of patient geometries. RESULTS Validation of these models against the gold standard CT-based approach showed no statistically significant inter-modality difference regarding vessel radius or curvature (p > 0.05), and a similar Dice Similarity Coefficient and Hausdorff Distance. CFD-derived near-wall hemodynamics indicated a significant inter-modality difference (p > 0.05), though these absolute errors were small. When compared to the in vivo data, CFD-derived velocities were qualitatively similar. CONCLUSION This proof-of-concept study demonstrated that functional 4D Flow-MRI information can be utilized to retrospectively generate anatomical information for CFD models in the absence of standard imaging datasets and intravenous contrast.
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Affiliation(s)
| | - Craig Maclean
- Research and Development, Terumo Aortic, Glasgow, UK
| | - Pauline Hall Barrientos
- Clinical Physics, Queen Elizabeth University Hospital, NHS Greater Glasgow & Clyde, Glasgow, UK
| | - Konstantinos Ritos
- Department of Mechanical and Aerospace Engineering, Glasgow, UK
- Department of Mechanical Engineering, University of Thessaly, Volos, Greece
| | - Asimina Kazakidi
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, UK.
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12
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Salmasi MY, Pirola S, Asimakopoulos G, Nienaber C, Athanasiou T. Risk prediction for thoracic aortic dissection: Is it time to go with the flow? J Thorac Cardiovasc Surg 2023; 166:1034-1042. [PMID: 35672182 DOI: 10.1016/j.jtcvs.2022.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/21/2022] [Accepted: 05/03/2022] [Indexed: 11/26/2022]
Affiliation(s)
- M Yousuf Salmasi
- Department of Surgery, Imperial College London, London, United Kingdom.
| | - Selene Pirola
- BHF Centre of Research Excellence, Institute of Clinical Sciences, Imperial College London, London, United Kingdom
| | - George Asimakopoulos
- Department of Cardiology, Royal Brompton and Harefield Trust, London, United Kingdom
| | - Christoph Nienaber
- Department of Cardiology, Royal Brompton and Harefield Trust, London, United Kingdom
| | - Thanos Athanasiou
- Department of Surgery, Imperial College London, London, United Kingdom
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13
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Mulorz J, Garcon F, Arnautovic A, De Somer C, Knapsis A, Aubin H, Fleissner F, Rembe JD, Vockel M, Oberhuber A, Lichtenberg A, Schelzig H, Wagenhäuser MU. The Role of Spatial Aortic Arch Architecture in Type B Aortic Dissection. J Clin Med 2023; 12:5963. [PMID: 37762902 PMCID: PMC10532254 DOI: 10.3390/jcm12185963] [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: 08/13/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
OBJECTIVE The incidence of type B aortic dissection (TBAD) is increasing worldwide; however, the underlying pathomechanisms are not conclusively understood. This study explores the geometric architecture of the aortic arch and supra-aortic branches in TBAD patients as opposed to non-TBAD patients. METHODS Patient characteristics were retrieved from archived medical records. Computer-assisted tomography (CAT) scans of patients with TBAD and carotid stenosis (CS) from two high-volume centers were analyzed. Various aortic arch parameters and take-off angles of the supra-aortic branches of TBAD patients were measured following centerline normalization in comparison CS patients. A compression index (C-index) was calculated from the para-sagittal, and a torsion index (T-index) was calculated from the para-coronal take-off angles of the supra-aortic branches to analyze aortic arch tortuosity. RESULTS A total of 199 CAT scans were analyzed, namely, 85 in the TBAD group and 114 in the CS group. The average age was 61.5 ± 13.1 years among the TBAD patients and 71 ± 9.3 years among the CS patients. We found a significantly higher proportion of type III aortic arch configurations in TBAD patients compared with CS patients. Further, the aortic arch angle was steeper in the TBAD group. In the para-sagittal plane, the left subclavian artery (LSA) take-off angle was less steep in TBAD patients. In the para-coronal plane, the left carotid artery (LCA) had a less steep take-off angle, while the LSA had a more obtuse take-off angle in the TBAD group when compared with the CS group. In addition, the inter-vessel distance was increased in TBAD patients. Finally, the T-index was increased, suggesting a significant torsion resulting from the deviating take-off angles of the supra-aortic branches supplying the left half of the body as opposed to the innominate artery (IA) in TBAD patients. CONCLUSIONS Our results suggest several aortic arch-specific geometric configurations in patients suffering from TBAD that significantly differ from those in CS patients. Further functional studies are needed to verify the pathogenetic relevance of our results and their disease-specific causality. Although our data are not mechanistically explorative, they may serve as a basis for identifying future patients with aortic arch morphology at higher risk for TBAD development and who may benefit from more stringent adjustment of risk factors as a primary prevention concept.
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Affiliation(s)
- Joscha Mulorz
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Franziska Garcon
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Amir Arnautovic
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Casper De Somer
- Institute for Biomedical Engineering and Technology, Ghent University, 9000 Ghent, Belgium
| | - Artis Knapsis
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Hug Aubin
- Department of Cardiac Surgery, Medical Faculty and University Hospital Duesseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
- CURE3D Laboratory, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Felix Fleissner
- Department of Cardiac Surgery, Medical Faculty and University Hospital Duesseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Julian-Dario Rembe
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Malwina Vockel
- Department of Vascular and Endovascular Surgery, University Hospital Muenster, 48149 Muenster, Germany
| | - Alexander Oberhuber
- Department of Vascular and Endovascular Surgery, University Hospital Muenster, 48149 Muenster, Germany
| | - Artur Lichtenberg
- Department of Cardiac Surgery, Medical Faculty and University Hospital Duesseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
- Cardiovascular Research Institute Düsseldorf (CARID), Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Hubert Schelzig
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Markus Udo Wagenhäuser
- Clinic for Vascular and Endovascular Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, 40225 Düsseldorf, Germany
- Department of Vascular- and Endovascular Surgery, University Hospital Düsseldorf, Moorenstraße 5, 40225 Düsseldorf, Germany
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14
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Ganizada BH, Reesink KD, Parikh S, Ramaekers MJFG, Akbulut AC, Saraber PJMH, Debeij GP, Jaminon AM, Natour E, Lorusso R, Wildberger JE, Mees B, Schurink GW, Jacobs MJ, Cleutjens J, Krapels I, Gombert A, Maessen JG, Accord R, Delhaas T, Schalla S, Schurgers LJ, Bidar E. The Maastricht Acquisition Platform for Studying Mechanisms of Cell-Matrix Crosstalk (MAPEX): An Interdisciplinary and Systems Approach towards Understanding Thoracic Aortic Disease. Biomedicines 2023; 11:2095. [PMID: 37626592 PMCID: PMC10452257 DOI: 10.3390/biomedicines11082095] [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: 06/19/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
Current management guidelines for ascending thoracic aortic aneurysms (aTAA) recommend intervention once ascending or sinus diameter reaches 5-5.5 cm or shows a growth rate of >0.5 cm/year estimated from echo/CT/MRI. However, many aTAA dissections (aTAAD) occur in vessels with diameters below the surgical intervention threshold of <55 mm. Moreover, during aTAA repair surgeons observe and experience considerable variations in tissue strength, thickness, and stiffness that appear not fully explained by patient risk factors. To improve the understanding of aTAA pathophysiology, we established a multi-disciplinary research infrastructure: The Maastricht acquisition platform for studying mechanisms of tissue-cell crosstalk (MAPEX). The explicit scientific focus of the platform is on the dynamic interactions between vascular smooth muscle cells and extracellular matrix (i.e., cell-matrix crosstalk), which play an essential role in aortic wall mechanical homeostasis. Accordingly, we consider pathophysiological influences of wall shear stress, wall stress, and smooth muscle cell phenotypic diversity and modulation. Co-registrations of hemodynamics and deep phenotyping at the histological and cell biology level are key innovations of our platform and are critical for understanding aneurysm formation and dissection at a fundamental level. The MAPEX platform enables the interpretation of the data in a well-defined clinical context and therefore has real potential for narrowing existing knowledge gaps. A better understanding of aortic mechanical homeostasis and its derangement may ultimately improve diagnostic and prognostic possibilities to identify and treat symptomatic and asymptomatic patients with existing and developing aneurysms.
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Affiliation(s)
- Berta H. Ganizada
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Koen D. Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Shaiv Parikh
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Mitch J. F. G. Ramaekers
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Asim C. Akbulut
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Stem Cell Research University Maastricht Facility, 6229 ER Maastricht, The Netherlands
| | - Pepijn J. M. H. Saraber
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Gijs P. Debeij
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - MUMC-TAA Student Team
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Armand M. Jaminon
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Ehsan Natour
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Roberto Lorusso
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Joachim E. Wildberger
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Barend Mees
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Geert Willem Schurink
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Michael J. Jacobs
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Jack Cleutjens
- Department of Pathology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Ingrid Krapels
- Department of Clinical Genetics, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Alexander Gombert
- Department of Vascular Surgery, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Jos G. Maessen
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Ryan Accord
- Department of Cardiothoracic Surgery, Center for Congenital Heart Diseases, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Simon Schalla
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Leon J. Schurgers
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Stem Cell Research University Maastricht Facility, 6229 ER Maastricht, The Netherlands
- Institute of Experimental Medicine and Systems Biology, RWTH Aachen University, 52074 Aachen, Germany
| | - Elham Bidar
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
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15
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Black SM, Maclean C, Hall Barrientos P, Ritos K, McQueen A, Kazakidi A. Calibration of patient-specific boundary conditions for coupled CFD models of the aorta derived from 4D Flow-MRI. Front Bioeng Biotechnol 2023; 11:1178483. [PMID: 37251565 PMCID: PMC10210162 DOI: 10.3389/fbioe.2023.1178483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 04/21/2023] [Indexed: 05/31/2023] Open
Abstract
Introduction: Patient-specific computational fluid dynamics (CFD) models permit analysis of complex intra-aortic hemodynamics in patients with aortic dissection (AD), where vessel morphology and disease severity are highly individualized. The simulated blood flow regime within these models is sensitive to the prescribed boundary conditions (BCs), so accurate BC selection is fundamental to achieve clinically relevant results. Methods: This study presents a novel reduced-order computational framework for the iterative flow-based calibration of 3-Element Windkessel Model (3EWM) parameters to generate patient-specific BCs. These parameters were calibrated using time-resolved flow information derived from retrospective four-dimensional flow magnetic resonance imaging (4D Flow-MRI). For a healthy and dissected case, blood flow was then investigated numerically in a fully coupled zero dimensional-three dimensional (0D-3D) numerical framework, where the vessel geometries were reconstructed from medical images. Calibration of the 3EWM parameters was automated and required ~3.5 min per branch. Results: With prescription of the calibrated BCs, the computed near-wall hemodynamics (time-averaged wall shear stress, oscillatory shear index) and perfusion distribution were consistent with clinical measurements and previous literature, yielding physiologically relevant results. BC calibration was particularly important in the AD case, where the complex flow regime was captured only after BC calibration. Discussion: This calibration methodology can therefore be applied in clinical cases where branch flow rates are known, for example, via 4D Flow-MRI or ultrasound, to generate patient-specific BCs for CFD models. It is then possible to elucidate, on a case-by-case basis, the highly individualized hemodynamics which occur due to geometric variations in aortic pathology high spatiotemporal resolution through CFD.
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Affiliation(s)
- Scott MacDonald Black
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, United Kingdom
| | - Craig Maclean
- Research and Development, Terumo Aortic, Glasgow, United Kingdom
| | - Pauline Hall Barrientos
- Clinical Physics, Queen Elizabeth University Hospital, NHS Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Konstantinos Ritos
- Department of Mechanical and Aerospace Engineering, University of Strathclyde, Glasgow, United Kingdom
- Department of Mechanical Engineering, University of Thessaly, Volos, Greece
| | - Alistair McQueen
- Department of Biomedical Engineering, University of Glasgow, Glasgow, United Kingdom
| | - Asimina Kazakidi
- Department of Biomedical Engineering, University of Strathclyde, Glasgow, United Kingdom
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16
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Juffermans JF, Westenberg JJM, van den Boogaard PJ, Lamb HJ. Effects of ageing on aortic hemodynamics measured by 4D-flow MRI: a case series. Eur Heart J Case Rep 2023; 7:ytad130. [PMID: 37090762 PMCID: PMC10113929 DOI: 10.1093/ehjcr/ytad130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/06/2022] [Accepted: 03/22/2023] [Indexed: 04/25/2023]
Abstract
Background It has been demonstrated that the rate of aortic dilatation is influenced by alteration of aortic hemodynamics, such as normalized flow displacement (FDN) and wall shear stress (WSS). However, the effects of ageing on aortic hemodynamics have not yet been described. Case summary 4D-Flow MRI derived aorta hemodynamics were derived in the ascending aorta of a patient with ascending aortic aneurysm (mean ± standard deviation: 46 ± 1 mm) and a healthy volunteer (aortic diameter 30 ± 1 mm) with long-term follow-up of ten and eight years, respectively. At all timepoints, compared to the healthy volunteer, the patient demonstrated higher magnitudes of FDN (7% ± 1% vs. 3% ± 1%) and WSS angle (36° ± 3° vs. 24° ± 6°), and lower WSS magnitude (565 ± 100 mPa vs. 910 ± 115 mPa), axial WSS (426 ± 71 mPa vs. 800 ± 108 mPa) and circumferential WSS (297 ± 64 mPa vs. 340 ± 85 mPa). The patient and healthy volunteer demonstrated different aortic dilatation rates (regression slope ± standard error: 0.2 ± 0.1 vs. 0.1 ± 0.2 mm per year) and trends in FDN (0.1% ± 0.1% vs. 0.1% ± 0.2% per year), WSS magnitude (22 ± 9 vs. 35 ± 13 mPa per year), axial WSS (19 ± 4 vs. 37 ± 7 mPa per year), circumferential WSS (9 ± 8 vs. 5 ± 15 mPa per year), and WSS angle (-0.5° ± 0.4° vs. -0.8° ± 1.0° per year). Discussion Aortic hemodynamic parameters are marginally affected by ageing and the aortic diameter in this case series. Since aortic hemodynamic parameters have been associated with aortic dilation by previous studies, the outcomes of the two subjects suggest that the aortic dilatation rate will remain constant while individuals are ageing and dilating.
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Affiliation(s)
- Joe F Juffermans
- Corresponding author. Tel: +31 71 526 22 33, Fax: +31 71 524 82 56,
| | - Jos J M Westenberg
- Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Pieter J van den Boogaard
- Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
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17
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A computational study of aortic reconstruction in single ventricle patients. Biomech Model Mechanobiol 2023; 22:357-377. [PMID: 36335184 PMCID: PMC10174275 DOI: 10.1007/s10237-022-01650-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 10/12/2022] [Indexed: 11/06/2022]
Abstract
Patients with hypoplastic left heart syndrome (HLHS) are born with an underdeveloped left heart. They typically receive a sequence of surgeries that result in a single ventricle physiology called the Fontan circulation. While these patients usually survive into early adulthood, they are at risk for medical complications, partially due to their lower than normal cardiac output, which leads to insufficient cerebral and gut perfusion. While clinical imaging data can provide detailed insight into cardiovascular function within the imaged region, it is difficult to use these data for assessing deficiencies in the rest of the body and for deriving blood pressure dynamics. Data from patients used in this paper include three-dimensional, magnetic resonance angiograms (MRA), time-resolved phase contrast cardiac magnetic resonance images (4D-MRI) and sphygmomanometer blood pressure measurements. The 4D-MRI images provide detailed insight into velocity and flow in vessels within the imaged region, but they cannot predict flow in the rest of the body, nor do they provide values of blood pressure. To remedy these limitations, this study combines the MRA, 4D-MRI, and pressure data with 1D fluid dynamics models to predict hemodynamics in the major systemic arteries, including the cerebral and gut vasculature. A specific focus is placed on studying the impact of aortic reconstruction occurring during the first surgery that results in abnormal vessel morphology. To study these effects, we compare simulations for an HLHS patient with simulations for a matched control patient that has double outlet right ventricle (DORV) physiology with a native aorta. Our results show that the HLHS patient has hypertensive pressures in the brain as well as reduced flow to the gut. Wave intensity analysis suggests that the HLHS patient has irregular circulatory function during light upright exercise conditions and that predicted wall shear stresses are lower than normal, suggesting the HLHS patient may have hypertension.
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18
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Qin JJ, Obeidy P, Gok M, Gholipour A, Grieve SM. 4D-flow MRI derived wall shear stress for the risk stratification of bicuspid aortic valve aortopathy: A systematic review. Front Cardiovasc Med 2023; 9:1075833. [PMID: 36698944 PMCID: PMC9869052 DOI: 10.3389/fcvm.2022.1075833] [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: 10/21/2022] [Accepted: 12/20/2022] [Indexed: 01/11/2023] Open
Abstract
Purpose Current intervention guidelines for bicuspid aortic valve (BAV) associated ascending aorta (AAo) dilatation are suboptimal predictors of clinical outcome. There is growing interest in identifying better biomarkers such as wall shear stress (WSS) to help risk stratify BAV aortopathy. The aim of the systematic review is to synthesize existing evidence of the relationship between WSS and aortopathy in the BAV population. Methods A comprehensive literature search of available major databases was performed in May 2022 to include studies that used four-dimensional flow cardiac magnetic resonance (4D-flow) MRI to quantify WSS in the AAo in adult BAV populations. Summary results and statistical analysis were provided for key numerical results. A narrative summary was provided to assess similarities between studies. Results A total of 26 studies that satisfied selection criteria and quality assessment were included in the review. The presence of BAV resulted in significantly elevated WSS magnitude and circumferential WSS, but not axial WSS. The presence of aortic stenosis had additional impact on WSS and flow alterations. BAV phenotypes were associated with different WSS distributions and flow profiles. Altered protein expression in the AAo wall associated with WSS supported the contribution of altered hemodynamics to aortopathy in addition to genetic factors. Conclusion WSS has the potential to be a valid biomarker for BAV aortopathy. Future work would benefit from larger study cohorts with longitudinal evaluations to further characterize WSS association with aortopathy, mortality, and morbidities. Systematic review registration https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022337077, identifier CRD42022337077.
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Affiliation(s)
- Jiaxing Jason Qin
- Imaging and Phenotyping Laboratory, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,Sydney Medical School and School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Peyman Obeidy
- Imaging and Phenotyping Laboratory, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,Sydney Medical School and School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Mustafa Gok
- Imaging and Phenotyping Laboratory, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,Sydney Medical School and School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,Department of Radiology, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Turkey
| | - Alireza Gholipour
- Imaging and Phenotyping Laboratory, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,Sydney Medical School and School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Stuart M. Grieve
- Imaging and Phenotyping Laboratory, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia,Sydney Medical School and School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,*Correspondence: Stuart M. Grieve,
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19
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Ito H, Ogihara Y, Ishida M, Ito H, Imanaka-Yoshida K, Dohi K. Assessment of Pseudocoarctation of the Aorta with Saccular Aneurysms by Four-Dimensional Flow Magnetic Resonance Imaging and Histological Analysis. Ann Vasc Dis 2022; 15:348-351. [PMID: 36644272 PMCID: PMC9816040 DOI: 10.3400/avd.cr.22-00077] [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: 07/13/2022] [Accepted: 10/13/2022] [Indexed: 11/27/2022] Open
Abstract
In this study, we present the case of a 21-year-old woman with pseudocoarctation of the aorta with saccular aneurysms that were evaluated by four-dimensional flow magnetic resonance imaging and histological analysis. We observed complete occupation of the aneurysm sacs by vortex flow and high peak wall shear stress in the proximal region of the kinked aorta. The aortic replacement was performed for the thoracic aortic aneurysms and the clinical course was uneventful. The aneurysms were histopathologically diagnosed as pseudoaneurysms based on the disappearance of all three layers and their replacement with collagen-rich connective tissues. These findings indicate that abnormal flow dynamics and the resulting abnormal shear stress in the aorta may play central roles in the formation and development of a saccular aneurysm.
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Affiliation(s)
- Hiromasa Ito
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Yoshito Ogihara
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu, Mie, Japan,Corresponding author: Yoshito Ogihara, MD, PhD. Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu, Mie 514-8507, Japan Tel: +81-59-231-5015, Fax: +81-59-231-5201, E-mail:
| | - Masaki Ishida
- Department of Radiology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Hisato Ito
- Department of Thoracic and Cardiovascular Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Kyoko Imanaka-Yoshida
- Department of Pathology and Matrix Biology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Kaoru Dohi
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
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20
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Rabineau J, Issertine M, Hoffmann F, Gerlach D, Caiani EG, Haut B, van de Borne P, Tank J, Migeotte PF. Cardiovascular deconditioning and impact of artificial gravity during 60-day head-down bed rest—Insights from 4D flow cardiac MRI. Front Physiol 2022; 13:944587. [PMID: 36277205 PMCID: PMC9586290 DOI: 10.3389/fphys.2022.944587] [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: 05/15/2022] [Accepted: 09/13/2022] [Indexed: 12/03/2022] Open
Abstract
Microgravity has deleterious effects on the cardiovascular system. We evaluated some parameters of blood flow and vascular stiffness during 60 days of simulated microgravity in head-down tilt (HDT) bed rest. We also tested the hypothesis that daily exposure to 30 min of artificial gravity (1 g) would mitigate these adaptations. 24 healthy subjects (8 women) were evenly distributed in three groups: continuous artificial gravity, intermittent artificial gravity, or control. 4D flow cardiac MRI was acquired in horizontal position before (−9 days), during (5, 21, and 56 days), and after (+4 days) the HDT period. The false discovery rate was set at 0.05. The results are presented as median (first quartile; third quartile). No group or group × time differences were observed so the groups were combined. At the end of the HDT phase, we reported a decrease in the stroke volume allocated to the lower body (−30% [−35%; −22%]) and the upper body (−20% [−30%; +11%]), but in different proportions, reflected by an increased share of blood flow towards the upper body. The aortic pulse wave velocity increased (+16% [+9%; +25%]), and so did other markers of arterial stiffness (CAVI; CAVI0). In males, the time-averaged wall shear stress decreased (−13% [−17%; −5%]) and the relative residence time increased (+14% [+5%; +21%]), while these changes were not observed among females. Most of these parameters tended to or returned to baseline after 4 days of recovery. The effects of the artificial gravity countermeasure were not visible. We recommend increasing the load factor, the time of exposure, or combining it with physical exercise. The changes in blood flow confirmed the different adaptations occurring in the upper and lower body, with a larger share of blood volume dedicated to the upper body during (simulated) microgravity. The aorta appeared stiffer during the HDT phase, however all the changes remained subclinical and probably the sole consequence of reversible functional changes caused by reduced blood flow. Interestingly, some wall shear stress markers were more stable in females than in males. No permanent cardiovascular adaptations following 60 days of HDT bed rest were observed.
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Affiliation(s)
- Jeremy Rabineau
- LPHYS, Département de Cardiologie, Université Libre de Bruxelles, Brussels, Belgium
- TIPs, École Polytechnique de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
- *Correspondence: Jeremy Rabineau,
| | - Margot Issertine
- LPHYS, Département de Cardiologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Fabian Hoffmann
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Darius Gerlach
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
| | - Enrico G. Caiani
- Electronic, Information and Biomedical Engineering Department, Politecnico di Milano, Milan, Italy
| | - Benoit Haut
- TIPs, École Polytechnique de Bruxelles, Université Libre de Bruxelles, Brussels, Belgium
| | | | - Jens Tank
- Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany
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21
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Kannojiya V, Das AK, Das PK. Effect of left ventricular assist device on the hemodynamics of a patient-specific left heart. Med Biol Eng Comput 2022; 60:1705-1721. [DOI: 10.1007/s11517-022-02572-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 04/07/2022] [Indexed: 11/28/2022]
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22
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Ferdian E, Dubowitz DJ, Mauger CA, Wang A, Young AA. WSSNet: Aortic Wall Shear Stress Estimation Using Deep Learning on 4D Flow MRI. Front Cardiovasc Med 2022; 8:769927. [PMID: 35141290 PMCID: PMC8818720 DOI: 10.3389/fcvm.2021.769927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/30/2021] [Indexed: 11/13/2022] Open
Abstract
Wall shear stress (WSS) is an important contributor to vessel wall remodeling and atherosclerosis. However, image-based WSS estimation from 4D Flow MRI underestimates true WSS values, and the accuracy is dependent on spatial resolution, which is limited in 4D Flow MRI. To address this, we present a deep learning algorithm (WSSNet) to estimate WSS trained on aortic computational fluid dynamics (CFD) simulations. The 3D CFD velocity and coordinate point clouds were resampled into a 2D template of 48 × 93 points at two inward distances (randomly varied from 0.3 to 2.0 mm) from the vessel surface (“velocity sheets”). The algorithm was trained on 37 patient-specific geometries and velocity sheets. Results from 6 validation and test cases showed high accuracy against CFD WSS (mean absolute error 0.55 ± 0.60 Pa, relative error 4.34 ± 4.14%, 0.92 ± 0.05 Pearson correlation) and noisy synthetic 4D Flow MRI at 2.4 mm resolution (mean absolute error 0.99 ± 0.91 Pa, relative error 7.13 ± 6.27%, and 0.79 ± 0.10 Pearson correlation). Furthermore, the method was applied on in vivo 4D Flow MRI cases, effectively estimating WSS from standard clinical images. Compared with the existing parabolic fitting method, WSSNet estimates showed 2–3 × higher values, closer to CFD, and a Pearson correlation of 0.68 ± 0.12. This approach, considering both geometric and velocity information from the image, is capable of estimating spatiotemporal WSS with varying image resolution, and is more accurate than existing methods while still preserving the correct WSS pattern distribution.
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Affiliation(s)
- Edward Ferdian
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
- *Correspondence: Edward Ferdian
| | - David J. Dubowitz
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
| | - Charlene A. Mauger
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
| | - Alan Wang
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Alistair A. Young
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
- Department of Biomedical Engineering, King's College London, London, United Kingdom
- Alistair A. Young
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23
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Nishimura T, Sueyoshi E, Koike H, Uetani M. Initial experience with intensity distribution analysis of hemodynamic parameters in the thoracic aorta using four-dimensional magnetic resonance imaging: A comparison between groups with different ejection fractions. Medicine (Baltimore) 2022; 101:e28563. [PMID: 35029224 PMCID: PMC8757938 DOI: 10.1097/md.0000000000028563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/21/2021] [Indexed: 11/26/2022] Open
Abstract
The purpose of this study was to investigate whether there were significant differences in the intensity distributions of thoracic aorta hemodynamic parameters between groups with different ejection fractions (EF) using four-dimensional flow magnetic resonance imaging and to investigate the relationships between each parameter.A total of 26 patients, 13 each with EF of >60% and <30%, underwent cardiac four-dimensional flow magnetic resonance imaging (EF >60%: mean age: 54 ± 11.6 years, EF <30%: mean age: 49.2 ± 17.2 years). The thoracic aorta was divided into the proximal and distal ascending aorta (AAo), aortic arch, and the proximal and distal descending aorta, and each section was further divided into the anterior wall, posterior wall, lesser curvature, and greater curvature. The intensity distributions of wall shear stress (WSS), energy loss (EL), and vorticity (Vort) (hemodynamic parameters) and the concordance rates between these distributions were analyzed.The concordance rate between the intensity distributions of EL and Vort was high. Only the intensity distributions of EL and Vort in the distal AAo differed significantly between the groups (P < .001). In the EF >60% group, these intensity distributions showed higher values in the greater curvature of the AAo, whereas in the EF <30% group higher values were seen in the lesser curvature of the AAo.Although there was no significant intergroup difference in the WSS intensity distribution, in the EF <30% group the WSS intensity distribution tended to exhibit higher values in the lesser curvature of the distal AAo, and the WSS intensity distribution values for the greater curvature tended to gradually increase from the arch to the proximal descending aorta.The only significant differences between the EF groups were found in the intensity distributions of EL and Vort in the distal AAo. This suggests that the distributions of atherosclerosis may be EF-dependent.
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24
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Minderhoud SCS, Roos-Hesselink JW, Chelu RG, Bons LR, van den Hoven AT, Korteland SA, van den Bosch AE, Budde RPJ, Wentzel JJ, Hirsch A. Wall shear stress angle is associated with aortic growth in bicuspid aortic valve patients. Eur Heart J Cardiovasc Imaging 2022; 23:1680-1689. [PMID: 34977931 DOI: 10.1093/ehjci/jeab290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 12/18/2021] [Indexed: 02/01/2023] Open
Abstract
AIMS Aortic wall shear stress (WSS) distributions in bicuspid aortic valve (BAV) patients have been associated with aortic dilatation, but prospective, longitudinal data are missing. This study assessed differences in aortic WSS distributions between BAV patients and healthy controls and determined the association of WSS with aortic growth in patients. METHODS AND RESULTS Sixty subjects underwent four-dimensional (4D) flow cardiovascular magnetic resonance of the thoracic aorta (32 BAV patients and 28 healthy controls). Peak velocity, pulse wave velocity, aortic distensibility, peak systolic WSS (magnitude, axial, and circumferential), and WSS angle were assessed. WSS angle is defined as the angle between the WSSmagnitude and WSSaxial component. In BAV patients, three-year computed tomography angiography-based aortic volumetric growth was determined in the proximal and entire ascending aorta. WSSaxial was significantly lower in BAV patients compared with controls (0.93 vs. 0.72 Pa, P = 0.047) and WSScircumferential and WSS angle were significantly higher (0.29 vs. 0.64 Pa and 18° vs. 40°, both P < 0.001). Significant volumetric growth of the proximal ascending aorta occurred in BAV patients (from 49.1 to 52.5 cm3, P = 0.003). In multivariable analysis corrected for baseline aortic volume and diastolic blood pressure, WSS angle was the only parameter independently associated with proximal aortic growth (P = 0.031). In the entire ascending aorta, besides the WSS angle, the WSSmagnitude was also independently associated with growth. CONCLUSION Increased WSScircumferential and especially WSS angle are typical in BAV patients. WSS angle was found to predict aortic growth. These findings highlight the potential role of WSS measurements in BAV patients to stratify patients at risk for aortic dilation.
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Affiliation(s)
- Savine C S Minderhoud
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Jolien W Roos-Hesselink
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Raluca G Chelu
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Lidia R Bons
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Allard T van den Hoven
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Suze-Anne Korteland
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Annemien E van den Bosch
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Ricardo P J Budde
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Jolanda J Wentzel
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Alexander Hirsch
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
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25
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Petuchova A, Maknickas A. Computational analysis of aortic haemodynamics in the presence of ascending aortic aneurysm. Technol Health Care 2022; 30:187-200. [PMID: 34806632 PMCID: PMC8842780 DOI: 10.3233/thc-219002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/21/2021] [Indexed: 11/15/2022]
Abstract
BACKGROUND The usefulness of numerical modelling of a patient's cardiovascular system is growing in clinical treatment. Understanding blood flow mechanics can be crucial in identifying connections between haemodynamic factors and aortic wall pathologies. OBJECTIVE This work investigates the haemodynamic parameters of an ascending aorta and ascending aortic aneurysm in humans. METHODS Two aortic models were constructed from medical images using the SimVascular software. FEM blood flow modelling of cardiac cycle was performed using CFD and CMM-FSI at different vascular wall parameters. RESULTS The results showed that highest blood velocity was 1.18 m/s in aorta with the aneurysm and 1.9 m/s in healthy aorta model. The largest displacements ware in the aorta with the aneurysm (0.73 mm). In the aorta with the aneurysm, time averaged WSS values throughout the artery range from 0 Pa to 1 Pa. In the healthy aorta, distribution of WSS values changes from 0.3 Pa to 0.6 Pa. CONCLUSIONS In the case of an ascending aortic aneurysm, the maximum blood velocity was found to be 1.6 times lower than in the healthy aorta. The aneurysm-based model demonstrates a 45% greater wall displacement, while the oscillatory shear index decreased by 30% compared to healthy aortic results.
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Affiliation(s)
- Aleksandra Petuchova
- Department of Biomechanical Engineering, Faculty of Mechanics, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Algirdas Maknickas
- Department of Biomechanical Engineering, Faculty of Mechanics, Vilnius Gediminas Technical University, Vilnius, Lithuania
- Laboratory of Numerical Simulation, Institute of Mechanics, Faculty of Mechanics, Vilnius Gediminas Technical University, Vilnius, Lithuania
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26
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Abstract
Aortic valve stenosis has become the most common valvular heart disease on account of aging population and increasing life expectancy. Echocardiography is the primary diagnosis tool for this, but it still has many flaws. Therefore, advanced cardiovascular multimodal imaging techniques are continuously being developed in order to overcome these limitations. Cardiac magnetic resonance imaging (CMR) allows a comprehensive morphological and functional evaluation of the aortic valve and provides important data for the diagnosis and risk stratification in patients with aortic stenosis. CMR can functionally assess the aortic flow using two-dimensional and time-resolved three-dimensional velocity-encoded phase-contrast techniques. Furthermore, by late gadolinium enhancement and T1-mapping, CMR can reveal the presence of both irreversible replacement and diffuse interstitial myocardial fibrosis. Moreover, its role in guiding aortic valve replacement procedures is beginning to take shape. Recent studies have rendered the importance of active and passive biomechanics in risk stratification and prognosis prediction in patients with aortic stenosis, but more work is required is just in its infancy, but data are promising. In addition, cardiac computed tomography is particularly useful for the diagnosis of aortic valve stenosis, and in preprocedural evaluation of the aorta, while positron emission tomography can be also used to assess valvular inflammation and active calcification. The purpose of this review is to provide a comprehensive overview of current available data regarding advanced cardiovascular multimodal imaging in aortic stenosis.
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27
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Sun X, Ma T, Liu Z, Wu X, Zhang B, Zhu S, Li F, Chen M, Zheng Y, Liu X. Sequential numerical simulation of vascular remodeling and thrombosis in unconventional hybrid repair of ruptured middle aortic syndrome. Med Eng Phys 2021; 94:87-95. [PMID: 34303507 DOI: 10.1016/j.medengphy.2021.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 06/16/2021] [Accepted: 06/28/2021] [Indexed: 11/26/2022]
Abstract
Unconventional surgical procedures may be utilized in treating complicated middle aortic syndrome (MAS), the outcome and prognosis of which remain largely undetermined due to limited numbers and significant heterogeneity of this population. Using computational fluid dynamics (CFD) analysis, this study aimed to assess the dynamic changes of postoperative aortic flow in seeking to unveil the relationship between hemodynamics and vascular remodeling and thrombotic events. One patient with middle aortic syndrome complicated with aortic rupture was treated with hybrid repair of extra-anatomic bypass and fenestrated endovascular aortic repair. The patient was followed-up for 8 months by computational tomography angiography and Doppler ultrasound. Thoracoabdominal aortic blood flow and locations with ongoing thrombosis at 1, 3, and 6 months postoperatively were simulated and analyzed. Remodeling processes, including low wall shear-mediated constrictive remodeling of non-stented aorta, neointimal hyperplasia at suture lines, and minimal thrombosis at various locations, were evident. Meanwhile, abdominal blood flow was tri-phasic at 1 month after surgery, and was reversed and stabilized at 6 months. The distribution of newly formed thrombus vary at different follow-up stages, which were in line with the numerical simulation of thrombosis from different postoperative time points. CFD-based sequential monitoring is of promising value in capturing dynamic changes of vascular outcome.
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Affiliation(s)
- Xiaoning Sun
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Tianxiang Ma
- Beijing Advanced Innovation Center for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Zhili Liu
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Xiao Wu
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Bo Zhang
- Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China; Department of Diagnostic Ultrasound, China-Japan Friendship Hospital, Beijing 100029, China
| | - Shenling Zhu
- Department of Diagnostic Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Fangda Li
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Mengyin Chen
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China
| | - Yuehong Zheng
- Department of Vascular Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
| | - Xiao Liu
- Beijing Advanced Innovation Center for Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.
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28
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Rabin A, Palacio D, Saqib N, Bar-Yoseph P, Weiss D, Afifi RO. Aortic aneurysms and dissections: Unmet needs from physicians and engineers perspectives. J Biomech 2021; 122:110461. [PMID: 33901933 DOI: 10.1016/j.jbiomech.2021.110461] [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: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 10/21/2022]
Abstract
The treatment of aortic disease is complex, requiring cardiothoracic and vascular surgeons to make pre-, post- and intraoperative decisions directly influencing patient survival and well-being. Despite tremendous advancement in vascular surgery and endovascular techniques in the last two decades, along with the abundance of research in the field, many unmet needs and unanswered questions remain. Tight collaboration between engineers and physicians is a keystone in translating new tools, techniques, and devices into practice. Here, we have gathered our perspective, as physicians and engineers, in several pressing issues associated with the diagnosis and treatment of aortic aneurysms and dissection, referring to the current knowledge and practice, signifying unmet needs as well as future directions.
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Affiliation(s)
- Asaf Rabin
- Department of Vascular and Endovascular Surgery Unit, B. Padeh M.C, Poriya, Israel.
| | - Diana Palacio
- Cardiothoracic Imaging Division, Department of Medical Imaging, The University of Arizona Banner Medical Center, Tucson, AZ, USA
| | - Naveed Saqib
- Department of Cardiothoracic and Vascular Surgery, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - Pinhas Bar-Yoseph
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Dar Weiss
- Department of Biomedical Engineering, Yale university, CT, USA
| | - Rana O Afifi
- Department of Cardiothoracic and Vascular Surgery, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA
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Shokina N, Teschner G, Bauer A, Tropea C, Egger H, Hennig J, Krafft AJ. Parametric Sequential Method for MRI-Based Wall Shear Stress Quantification. IEEE TRANSACTIONS ON MEDICAL IMAGING 2021; 40:1105-1112. [PMID: 33347405 DOI: 10.1109/tmi.2020.3046331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Wall shear stress (WSS) has been suggested as a potential biomarker in various cardiovascular diseases and it can be estimated from phase-contrast Magnetic Resonance Imaging (PC-MRI) velocity measurements. We present a parametric sequential method for MRI-based WSS quantification consisting of a geometry identification and a subsequent approximation of the velocity field. This work focuses on its validation, investigating well controlled high-resolution in vitro measurements of turbulent stationary flows and physiological pulsatile flows in phantoms. Initial tests for in vivo 2D PC-MRI data of the ascending aorta of three volunteers demonstrate basic applicability of the method to in vivo.
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30
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Secinaro A, Milano EG, Ciancarella P, Trezzi M, Capelli C, Ciliberti P, Cetrano E, Curione D, Santangelo TP, Napolitano C, Albanese SB, Carotti A. Blood flow characteristics after aortic valve neocuspidization in paediatric patients: a comparison with the Ross procedure. Eur Heart J Cardiovasc Imaging 2021; 23:275-282. [PMID: 33550364 PMCID: PMC8787994 DOI: 10.1093/ehjci/jeab009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 01/13/2021] [Indexed: 12/25/2022] Open
Abstract
Aims The aortic valve (AV) neocuspidization (Ozaki procedure) is a novel surgical technique for AV disease that preserves the natural motion and cardiodynamics of the aortic root. In this study, we sought to evaluate, by 4D-flow magnetic resonance imaging, the aortic blood flow characteristics after AV neocuspidization in paediatric patients. Methods and results Aortic root and ascending aorta haemodynamics were evaluated in a population of patients treated with the Ozaki procedure; results were compared with those of a group of patients operated with the Ross technique. Cardiovascular magnetic resonance studies were performed at 1.5 T using a 4D flow-sensitive sequence acquired with retrospective electrocardiogram-gating and respiratory navigator. Post-processing of 4D-flow analysis was performed to calculate flow eccentricity and wall shear stress. Twenty children were included in this study, 10 after Ozaki and 10 after Ross procedure. Median age at surgery was 10.7 years (range 3.9–16.5 years). No significant differences were observed in wall shear stress values measured at the level of the proximal ascending aorta between the two groups. The analysis of flow patterns showed no clear association between eccentric flow and the procedure performed. The Ozaki group showed just a slightly increased transvalvular maximum velocity. Conclusion Proximal aorta flow dynamics of children treated with the Ozaki and the Ross procedure are comparable. Similarly to the Ross, Ozaki technique restores a physiological laminar flow pattern in the short-term follow-up, with the advantage of not inducing a bivalvular disease, although further studies are warranted to evaluate its long-term results.
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Affiliation(s)
- Aurelio Secinaro
- Advanced Cardiovascular Imaging Unit, Department of Imaging, Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Elena Giulia Milano
- University College London, Institute of Cardiovascular Science, London, UK.,Great Ormond Street Hospital for Children, Department of Cardiology, London, UK
| | - Paolo Ciancarella
- Advanced Cardiovascular Imaging Unit, Department of Imaging, Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Matteo Trezzi
- Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Claudio Capelli
- University College London, Institute of Cardiovascular Science, London, UK
| | - Paolo Ciliberti
- Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Enrico Cetrano
- Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Davide Curione
- Advanced Cardiovascular Imaging Unit, Department of Imaging, Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Teresa Pia Santangelo
- Advanced Cardiovascular Imaging Unit, Department of Imaging, Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Carmela Napolitano
- Advanced Cardiovascular Imaging Unit, Department of Imaging, Bambino Gesù Children's Hospital, IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy
| | - Sonia B Albanese
- Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Adriano Carotti
- Department of Pediatric Cardiology and Cardiac Surgery, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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31
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Tanaka K, Joshi D, Timalsina S, Schwartz MA. Early events in endothelial flow sensing. Cytoskeleton (Hoboken) 2021; 78:217-231. [PMID: 33543538 DOI: 10.1002/cm.21652] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/29/2021] [Accepted: 01/31/2021] [Indexed: 12/15/2022]
Abstract
Responses of vascular and lymphatic endothelial cells (ECs) to fluid shear stress (FSS) from blood or lymphatic fluid flow govern the development, physiology, and diseases of these structures. Extensive research has characterized the signaling, gene expression and cytoskeletal pathways that mediate effects on EC phenotype and vascular morphogenesis. But the primary mechanisms by which ECs transduce the weak forces from flow into biochemical signals are less well understood. This review covers recent advances in our understanding of the immediate mechanisms of FSS mechanotransduction, integrating results from different disciplines, addressing their roles in development, physiology and disease, and suggesting important questions for future work.
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Affiliation(s)
- Keiichiro Tanaka
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Divyesh Joshi
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Sushma Timalsina
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA
| | - Martin A Schwartz
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, Connecticut, USA.,Department of Cell Biology, Yale University, New Haven, Connecticut, USA.,Department of Biomedical engineering, Yale University, New Haven, Connecticut, USA
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Schmidt S, Flassbeck S, Schmelter S, Schmeyer E, Ladd ME, Schmitter S. The impact of 4D flow displacement artifacts on wall shear stress estimation. Magn Reson Med 2021; 85:3154-3168. [PMID: 33421221 DOI: 10.1002/mrm.28641] [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: 08/06/2020] [Revised: 11/16/2020] [Accepted: 11/23/2020] [Indexed: 12/27/2022]
Abstract
PURPOSE To investigate the amplitude and spatial distribution of errors in wall shear stress (WSS) values derived from 4D flow measurements caused by displacement artifacts intrinsic to the 4D flow acquisition. METHODS Phase-contrast MRI velocimetry was performed in a model of a stenotic aorta using two different timing schemes, both of which are commonly applied in vivo but differ in their resulting displacement artifacts. Whereas one scheme is optimized to minimize the duration of the encoding gradients (herein called FAST), the other aims to specifically minimize displacement artifacts by synchronizing all three spatial-encoding time points (called ECHO). WSS estimates were calculated and compared to unbiased WSS values obtained by a 5-hour single-point imaging acquisition. In addition, MRI simulations based on computational fluid dynamics data were carried out to investigate the impact of gradient timings corresponding to different spatial resolutions. RESULTS 4D flow displacement artifacts were found to have an impact on the quantified WSS peak values, spatial location, and overall WSS pattern. FAST leads to the underestimation of local WSS values in the phantom arch by up to 90%. Moreover, the corresponding WSS estimates depend on the image orientation. This effect was avoided using ECHO, which, however, results in biased WSS values within the stenosis, yielding an underestimation of peak WSS by up to 17%. Computational fluid dynamics-based simulation results show that the bias in WSS due to displacement artifacts increases with increasing spatial resolution, thus counteracting the resolution benefit for WSS due to reduced partial volume effects and segmentation errors. CONCLUSIONS 4D flow displacement artifacts can significantly impact the WSS estimates and depend on the timing scheme as well as potentially the image orientation. Whereas FAST might allow correct WSS estimation for lower resolutions, ECHO is recommended especially when spatial resolutions of 1 mm and smaller are used. Users need to be aware of this nonnegligible effect, particularly when conducting inter-site studies or studies between vendors. The timing scheme should thus be explicitly mentioned in publications.
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Affiliation(s)
- Simon Schmidt
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Physics and Astronomy, Heidelberg University, Heidelberg, Germany
| | - Sebastian Flassbeck
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York, NY, USA.,Center for Advanced Imaging Innovation and Research, New York University School of Medicine, New York, NY, USA
| | - Sonja Schmelter
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Ellen Schmeyer
- Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
| | - Mark E Ladd
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Physics and Astronomy, Heidelberg University, Heidelberg, Germany.,Faculty of Medicine, Heidelberg University, Heidelberg, Germany
| | - Sebastian Schmitter
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany
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33
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Gutierrez MA. Computational Analysis of Fluid Dynamics in the Transcatheter Aortic Valve Replacement. Arq Bras Cardiol 2020; 115:688-689. [PMID: 33111870 PMCID: PMC8386972 DOI: 10.36660/abc.20201002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Marco A Gutierrez
- Instituto do Coração (InCor), Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP - Brasil
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Kyriakou F, Maclean C, Dempster W, Nash D. Efficiently Simulating an Endograft Deployment: A Methodology for Detailed CFD Analyses. Ann Biomed Eng 2020; 48:2449-2465. [PMID: 32394221 PMCID: PMC7505889 DOI: 10.1007/s10439-020-02519-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 04/24/2020] [Indexed: 01/10/2023]
Abstract
Numerical models of endografts for the simulation of endovascular aneurysm repair are increasingly important in the improvement of device designs and patient outcomes. Nevertheless, current finite element analysis (FEA) models of complete endograft devices come at a high computational cost, requiring days of runtime, therefore restricting their applicability. In the current study, an efficient FEA model of the Anaconda™ endograft (Terumo Aortic, UK) was developed, able to yield results in just over 4 h, an order of magnitude less than similar models found in the literature. The model was used to replicate a physical device that was deployed in a 3D printed aorta and comparison of the two shapes illustrated a less than 5 mm placement error of the model in the regions of interest, consistent with other more computationally intensive models in the literature. Furthermore, the final goal of the study was to utilize the deployed fabric model in a hemodynamic analysis that would incorporate realistic fabric folds, a feature that is almost always omitted in similar simulations. By successfully exporting the deployed graft geometry into a flow analysis, it was illustrated that the inclusion of fabric wrinkles enabled clinically significant flow patterns such as flow stagnation and recirculation to be detected, paving the way for this modelling methodology to be used in future for stent design optimisation.
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Affiliation(s)
- Faidon Kyriakou
- Department of Mechanical and Aerospace Engineering, University of Strathclyde, 75 Montrose Street, Glasgow, G1 1XJ, UK.
| | | | - William Dempster
- Department of Mechanical and Aerospace Engineering, University of Strathclyde, 75 Montrose Street, Glasgow, G1 1XJ, UK
| | - David Nash
- Department of Mechanical and Aerospace Engineering, University of Strathclyde, 75 Montrose Street, Glasgow, G1 1XJ, UK
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35
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Qiu Y, Yang D, Zhang Q, Chen K, Dong Y, Wang WP. V Flow technology in measurement of wall shear stress of common carotid arteries in healthy adults: Feasibility and normal values. Clin Hemorheol Microcirc 2020; 74:453-462. [PMID: 31683473 DOI: 10.3233/ch-190719] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To evaluate the feasibility of vector flow imaging technique (V Flow) in measurement of wall shear stress (WSS) of common carotid arteries (CCA) in healthy adults and to provide the normal WSS values assessed by V Flow. METHODS & MATERIALS This prospective study was approved by the Ethics Committee of our University. Eighty healthy adult volunteers were included (mean age 43.3 y, 47 females, 33 males). The volunteers were classified into three groups according to their age: group I (age 20 - 39 y), group II (age 40 - 59 y) and group III (age 60 - 80 y). Mindray Resona 8 ultrasound machine and a linear array transducer (3-9 MHz) was used, equipped with the updated V Flow function. Common carotid arteries of both sides were evaluated in three segments (initial segment, middle segment and near bifurcation segment). The WSS values of CCA were measured by two independent radiologists. The intraclass correlation coefficient (ICC) of observer reliability in WSS measurement was calculated. Inter-observer reproducibility was also evaluated with the 95% Bland-Altman limits of agreement (LOA). RESULTS V Flow measurements were performed successfully in 79 volunteers (98.8 %, 79/80). The mean value of WSS in right CCA was (0.66±0.24) Pa, in left CCA was (0.66±0.18) Pa (P > 0.05). Mean WSS value had a moderately negative correlation with age group (P < 0.05). The mean WSS value of group I(mean±SD, 0.75±0.25 Pa) is larger than group II (mean±SD, 0.62±0.13 Pa) and group III (mean±SD, 0.49±0.11 Pa) (P < 0.05). The ICC of observer reliability of group I, II and III was 0.96 (95% confidence interval (95% CI) 0.92-0.98), 0.94 (95% CI 0.88-0.97), 0.93 (95% CI 0.76-0.98) respectively. The Bland-Altman plots showed that the 95% LOA were -0.17-0.12 (Pa) for group I, -0.09-0.13 (Pa) for group II and -0.08-0.10 (Pa) for group III. CONCLUSION V Flow measurement is a simple, rapid and feasible imaging method for the WSS assessment of CCA in healthy volunteers, which will probably be an important tool for assessing CCA function.
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Affiliation(s)
- Yijie Qiu
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Daohui Yang
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qi Zhang
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Kailing Chen
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yi Dong
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Wen-Ping Wang
- Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
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36
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Scott MB, Huh H, van Ooij P, Chen V, Herrera B, Elbaz M, McCarthy P, Malaisrie SC, Carr J, Fedak PWM, Markl M, Barker AJ. Impact of age, sex, and global function on normal aortic hemodynamics. Magn Reson Med 2020; 84:2088-2102. [PMID: 32162416 DOI: 10.1002/mrm.28250] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 01/10/2020] [Accepted: 02/14/2020] [Indexed: 02/01/2023]
Abstract
PURPOSE To examine the effects of age, sex, and left ventricular global function on velocity, helicity, and 3D wall shear stress (3D-WSS) in the aorta of N = 100 healthy controls. METHODS Fifty female and 50 male volunteers with no history of cardiovascular disease, with 10 volunteers per age group (18-30, 31-40, 41-50, 51-60, and 61-80 years) underwent aortic 4D-flow MRI. Quantification of systolic aortic peak velocity, helicity, and 3D-WSS distribution and the calculation of age group-averaged peak systolic velocity and 3D-WSS maps ("atlases") were computed. Age-related and sex-related changes in peak velocity, helicity, and 3D-WSS were computed and correlated with standard metrics of left ventricular function derived from short-axis cine MRI. RESULTS No significant differences were found in peak systolic velocity or 3D-WSS based on sex except for the 18- to 30-year-old group (males 8% higher velocity volume and 3D-WSS surface area). Between successively older groups, systolic velocity decreased (13%, <1%, 7%, and 55% of the aorta volume) and 3D-WSS decreased (21%, 2%, 30%, and 62% of the aorta surface area). Mean velocity, mean 3D-3D-WSS, and median helicity increased with cardiac output (r = 0.27-0.43, all P < .01), and mean velocity and 3D-WSS decreased with increasing diameter (r > 0.35, P < .001). Arch and descending aorta systolic mean velocity, mean 3D-WSS, and median helicity increased with normalized left ventricular volumes: end diastolic volume (r = 0.31-0.37, P < .01), end systolic volume (r = 0.27-0.35, P < .01), and stroke volume (r = 0.28-0.35, P < .01). CONCLUSION Healthy aortic hemodynamics are dependent on subject age, and correlate with vessel diameter and cardiac function.
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Affiliation(s)
- Michael B Scott
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.,Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA
| | - Hyungkyu Huh
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Pim van Ooij
- Department of Radiology and Nuclear Medicine, Academic Medical Centre, Amsterdam, the Netherlands
| | - Vincent Chen
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Brenda Herrera
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Mohammed Elbaz
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Patrick McCarthy
- Bluhm Cardiovascular Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.,Division of Cardiac Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - S Chris Malaisrie
- Bluhm Cardiovascular Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.,Division of Cardiac Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - James Carr
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Paul W M Fedak
- Division of Cardiac Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.,Department of Cardiac Sciences, University of Calgary, Calgary, AB, Canada
| | - Michael Markl
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.,Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Evanston, IL, USA
| | - Alex J Barker
- Department of Radiology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
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37
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Bollache E, Fedak PWM, Markl M, Barker AJ. On the 'cusp' of clinical feasibility: aortic wall shear stress derived non-invasively with 4D flow MRI. J Thorac Dis 2019; 11:E96-E97. [PMID: 31463155 DOI: 10.21037/jtd.2019.06.54] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Emilie Bollache
- Sorbonne Université, CNRS, INSERM, Laboratoire d'Imagerie Biomédicale, Paris, France
| | - Paul W M Fedak
- Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Libin Cardiovascular Institute, Calgary, AB, Canada
| | - Michael Markl
- Department of Radiology, Feinberg School of Medicine, McCormick School of Engineering, Northwestern University, Chicago, IL, USA.,Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, USA
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38
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Shokina N, Bauer A, Teschner G, Buchenberg WB, Tropea C, Egger H, Hennig J, Krafft AJ. MR-based wall shear stress measurements in fully developed turbulent flow using the Clauser plot method. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 305:16-21. [PMID: 31158791 DOI: 10.1016/j.jmr.2019.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/21/2019] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
In arterial blood flow wall shear stress (WSS) quantifies the frictional force that flowing blood exerts on a vessel wall. WSS can be directly estimated from phase-contrast (PC) MR velocity measurements and has been suggested as a biomarker in cardio-vascular diseases. We present and investigate the application of the Clauser plot method for estimating WSS in fully developed turbulent stationary flow using PC velocity measurements. The Clauser plot method estimates WSS from the logarithmic region of boundary layer in fully developed turbulent stationary flow. The Clauser plot method was evaluated using 2D PC-MR phantom measurements at 3 T for different in-plane resolutions at various Reynolds numbers. WSS values derived from the Clauser plot were compared to results from Laser Doppler Velocimetry (LDV) measurements and theoretical results calculated using the friction factor formula for smooth pipe flow. For all Reynolds numbers, WSS values derived from the Clauser plot were in good agreement with results from LDV measurements and values using the friction factor formula (relative deviations ∼5%). Furthermore, Clauser plot derived results were almost independent of spatial resolution, in contrast to WSS results obtained with our in-house software tool for MR-based WSS quantification showing relative deviations of more than 100%. In fully developed turbulent flow, the Clauser plot method provides highly consistent WSS independent of the underlying spatial resolution. Therefore, it renders a valuable approach for MR-based WSS estimates in controllable flow settings. Although its direct in vivo applicability is severely limited because of the different flow character, it may serve as helpful approach for validation of MR-based WSS quantification algorithms prior to their clinical application.
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Affiliation(s)
- Nina Shokina
- Dept. of Radiology, Medical Physics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany.
| | - Andreas Bauer
- Institute for Fluid Mechanics and Aerodynamics, Department of Mechanical Engineering, Technische Universität Darmstadt, Darmstadt, Germany
| | - Gabriel Teschner
- Institute for Numerical Analysis and Scientific Computing, Department of Mathematics, Technische Universität Darmstadt, Darmstadt, Germany
| | - Waltraud B Buchenberg
- Dept. of Radiology, Medical Physics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Cameron Tropea
- Institute for Fluid Mechanics and Aerodynamics, Department of Mechanical Engineering, Technische Universität Darmstadt, Darmstadt, Germany
| | - Herbert Egger
- Institute for Numerical Analysis and Scientific Computing, Department of Mathematics, Technische Universität Darmstadt, Darmstadt, Germany
| | - Jürgen Hennig
- Dept. of Radiology, Medical Physics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Axel J Krafft
- Dept. of Radiology, Medical Physics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
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Carelli MG, Seco M, Bannon PG, Grieve SM. Is wall shear stress ready to become a prime-time clinical tool?-measurement of post-surgical patterns in patients undergoing aortic valve and thoracic aortic replacement using 4-dimensional flow magnetic resonance imaging. J Thorac Dis 2019; 11:S440-S442. [PMID: 30997242 PMCID: PMC6424770 DOI: 10.21037/jtd.2018.11.62] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 11/05/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Matheus G. Carelli
- Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, Camperdown, NSW 2050 Australia
| | - Michael Seco
- Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, Camperdown, NSW 2050 Australia
- Central Clinical School, Faculty of Medicine and Health, The University of Sydney, NSW 2050, Australia
| | - Paul G. Bannon
- Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, Camperdown, NSW 2050 Australia
- Central Clinical School, Faculty of Medicine and Health, The University of Sydney, NSW 2050, Australia
| | - Stuart M. Grieve
- Central Clinical School, Faculty of Medicine and Health, The University of Sydney, NSW 2050, Australia
- Sydney Translational Imaging Laboratory, Heart Research Institute, Charles Perkins Centre, The University of Sydney, NSW 2006, Australia
- Department of Radiology, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia
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