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Kara R, Vergara C. Assessing turbulent effects in ascending aorta in presence of bicuspid aortic valve. Comput Methods Biomech Biomed Engin 2023:1-13. [PMID: 37950490 DOI: 10.1080/10255842.2023.2279938] [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: 01/25/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
Aortic valves with bicuspids have two rather than three leaflets, which is a congenital heart condition. About 0.5-2% of people have a bicuspid aortic valve. Blood flow through the aorta is commonly believed to be laminar, although aortic valve disorders can cause turbulent transitions. Understanding the impact of turbulence is crucial for foreseeing how the disease will progress. The study's objective was use large eddy simulation to provide a thorough analysis of the turbulence in bicuspid aortic valve dysfunction. Using a large eddy simulation, the blood flow patterns of the bicuspid and tricuspid aortic valves were compared, and significant discrepancies were found. The velocity field in flow in bicuspid configurations was asymmetrically distributed toward the ascending aorta. In tricuspid aortic valve (TAV) the flow, on the other hand, was symmetrical within the same aortic segment. Moreover, we looked into standard deviation, Q-criterion, viscosity ratio and wall shear stresses for each cases to understand transition to turbulence. Our findings indicate that in the bicuspid aortic valve (BAV) case, the fluid-dynamic abnormalities increase. The global turbulent kinetic energy and time-averaged wall shear stress for the TAV and BAV scenarios were also examined. We discovered that the global turbulent kinetic energy was higher in the BAV case compared to TAV, in addition to the increased wall shear stress induced by the BAV in the ascending aorta.
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Affiliation(s)
- Rukiye Kara
- Department of Mathematics, Mimar Sinan Fine Arts University, Istanbul, Turkey
| | - Christian Vergara
- LABS - Dipartimento di Chimica, Materiali e Ingegneria Chimica" Giulio Natta" - Politecnico di Milano, Milan, Italy
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2
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Kim T, Tjahjadi NS, He X, van Herwaarden JA, Patel HJ, Burris NS, Figueroa CA. Three-Dimensional Characterization of Aortic Root Motion by Vascular Deformation Mapping. J Clin Med 2023; 12:4471. [PMID: 37445507 DOI: 10.3390/jcm12134471] [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: 06/05/2023] [Revised: 06/29/2023] [Accepted: 07/02/2023] [Indexed: 07/15/2023] Open
Abstract
The aorta is in constant motion due to the combination of cyclic loading and unloading with its mechanical coupling to the contractile left ventricle (LV) myocardium. This aortic root motion has been proposed as a marker for aortic disease progression. Aortic root motion extraction techniques have been mostly based on 2D image analysis and have thus lacked a rigorous description of the different components of aortic root motion (e.g., axial versus in-plane). In this study, we utilized a novel technique termed vascular deformation mapping (VDM(D)) to extract 3D aortic root motion from dynamic computed tomography angiography images. Aortic root displacement (axial and in-plane), area ratio and distensibility, axial tilt, aortic rotation, and LV/Ao angles were extracted and compared for four different subject groups: non-aneurysmal, TAA, Marfan, and repair. The repair group showed smaller aortic root displacement, aortic rotation, and distensibility than the other groups. The repair group was also the only group that showed a larger relative in-plane displacement than relative axial displacement. The Marfan group showed the largest heterogeneity in aortic root displacement, distensibility, and age. The non-aneurysmal group showed a negative correlation between age and distensibility, consistent with previous studies. Our results revealed a strong positive correlation between LV/Ao angle and relative axial displacement and a strong negative correlation between LV/Ao angle and relative in-plane displacement. VDM(D)-derived 3D aortic root motion can be used in future studies to define improved boundary conditions for aortic wall stress analysis.
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Affiliation(s)
- Taeouk Kim
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nic S Tjahjadi
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI 48109, USA
| | - Xuehuan He
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - J A van Herwaarden
- Department of Vascular Surgery, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Himanshu J Patel
- Department of Cardiac Surgery, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicholas S Burris
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109, USA
| | - C Alberto Figueroa
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Surgery, University of Michigan, Ann Arbor, MI 48109, USA
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3
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Ban E, Kalogerakos PD, Khosravi R, Ziganshin BA, Ellauzi H, Ramachandra AB, Zafar MA, Humphrey JD, Elefteriades JA. Extended law of laplace for measurement of the cloverleaf anatomy of the aortic root. Int J Cardiovasc Imaging 2023; 39:1345-1356. [PMID: 37046157 PMCID: PMC10250276 DOI: 10.1007/s10554-023-02847-5] [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: 11/30/2022] [Accepted: 03/27/2023] [Indexed: 04/14/2023]
Abstract
The cross-sectional shape of the aortic root is cloverleaf, not circular, raising controversy regarding how best to measure its radiographic "diameter" for aortic event prediction. We mathematically extended the law of Laplace to estimate aortic wall stress within this cloverleaf region, simultaneously identifying a new metric of aortic root dimension that can be applied to clinical measurement of the aortic root and sinuses of Valsalva on clinical computerized tomographic scans. Enforcing equilibrium between blood pressure and wall stress, finite element computations were performed to evaluate the mathematical derivation. The resulting Laplace diameter was compared with existing methods of aortic root measurement across four patient groups: non-syndromic aneurysm, bicuspid aortic valve, Marfan syndrome, and non-dilated root patients (total 106 patients, 62 M, 44 F). (1) Wall stress: Mean wall stress at the depth of the sinuses followed this equation: Wall stress = BP × Circumscribing circle diameter/(2 × Aortic wall thickness). Therefore, the diameter of the circle enclosing the root cloverleaf, that is, twice the distance between the center, where the sinus-to-commissure lines coincide, and the depth of the sinuses, may replace diameter in the Laplace relation for a cloverleaf cross-section (or any shaped cross-section with two or more planes of symmetry). This mathematically derived result was verified by computational finite element analyses. (2) Diameters: CT scan measurements showed a significant difference between this new metric, the Laplace diameter, and the sinus-to-commissure, mid-sinus-to-mid-sinus, and coronal measurements in all four groups (p-value < 0.05). The average Laplace diameter measurements differed significantly from the other measurements in all patient groups. Among the various possible measurements within the aortic root, the diameter of the circumscribing circle, enclosing the cloverleaf, represents the diameter most closely related to wall stress. This diameter is larger than the other measurements, indicating an underestimation of wall stress by prior measurements, and otherwise provides an unbiased, convenient, consistent, physics-based measurement for clinical use. "Diameter" applies to circles. Our mathematical derivation of an extension of the law of Laplace, from circular to cloverleaf cross-sectional geometries of the aortic root, has implications for measurement of aortic root "diameter." The suggested method is as follows: (1) the "center" of the aortic root is identified by drawing three sinus-to-commissure lines. The intersection of these three lines identifies the "center" of the cloverleaf. (2) The largest radius from this center point to any of the sinuses is identified as the "radius" of the aortic root. (3) This radius is doubled to give the "diameter" of the aortic root. We find that this diameter best corresponds to maximal wall stress in the aortic root. Please note that this diameter defines the smallest circle that completely encloses the cloverleaf shape, touching the depths of all three sinuses.
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Affiliation(s)
- Ehsan Ban
- Department of Biomedical Engineering, Yale University, New Haven, USA
| | | | - Ramak Khosravi
- Department of Biomedical Engineering, Yale University, New Haven, USA
| | - Bulat A Ziganshin
- Aortic Institute, Yale School of Medicine, CB-3, 789 Howard Ave., New Haven, CT, 06510, USA
| | - Hesham Ellauzi
- Aortic Institute, Yale School of Medicine, CB-3, 789 Howard Ave., New Haven, CT, 06510, USA
| | | | - Mohammad A Zafar
- Aortic Institute, Yale School of Medicine, CB-3, 789 Howard Ave., New Haven, CT, 06510, USA
| | - Jay D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, USA
| | - John A Elefteriades
- Aortic Institute, Yale School of Medicine, CB-3, 789 Howard Ave., New Haven, CT, 06510, USA.
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Wang X, Ghayesh MH, Kotousov A, Zander AC, Dawson JA, Psaltis PJ. Fluid-structure interaction study for biomechanics and risk factors in Stanford type A aortic dissection. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023:e3736. [PMID: 37258411 DOI: 10.1002/cnm.3736] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 04/04/2023] [Accepted: 05/16/2023] [Indexed: 06/02/2023]
Abstract
Aortic dissection is a life-threatening condition with a rising prevalence in the elderly population, possibly as a consequence of the increasing population life expectancy. Untreated aortic dissection can lead to myocardial infarction, aortic branch malperfusion or occlusion, rupture, aneurysm formation and death. This study aims to assess the potential of a biomechanical model in predicting the risks of a non-dilated thoracic aorta with Stanford type A dissection. To achieve this, a fully coupled fluid-structure interaction model was developed under realistic blood flow conditions. This model of the aorta was developed by considering three-dimensional artery geometry, multiple artery layers, hyperelastic artery wall, in vivo-based physiological time-varying blood velocity profiles, and non-Newtonian blood behaviours. The results demonstrate that in a thoracic aorta with Stanford type A dissection, the wall shear stress (WSS) is significantly low in the ascending aorta and false lumen, leading to potential aortic dilation and thrombus formation. The results also reveal that the WSS is highly related to blood flow patterns. The aortic arch region near the brachiocephalic and left common carotid artery is prone to rupture, showing a good agreement with the clinical reports. The results have been translated into their potential clinical relevance by revealing the role of the stress state, WSS and flow characteristics as the main parameters affecting lesion progression, including rupture and aneurysm. The developed model can be tailored for patient-specific studies and utilised as a predictive tool to estimate aneurysm growth and initiation of wall rupture inside the human thoracic aorta.
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Affiliation(s)
- Xiaochen Wang
- School of Mechanical Engineering, University of Adelaide, Adelaide, Australia
| | - Mergen H Ghayesh
- School of Mechanical Engineering, University of Adelaide, Adelaide, Australia
| | - Andrei Kotousov
- School of Mechanical Engineering, University of Adelaide, Adelaide, Australia
| | - Anthony C Zander
- School of Mechanical Engineering, University of Adelaide, Adelaide, Australia
| | - Joseph A Dawson
- Department of Vascular & Endovascular Surgery, Royal Adelaide Hospital, Adelaide, Australia
- Trauma Surgery Unit, Royal Adelaide Hospital, Adelaide, Australia
- Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Peter J Psaltis
- Adelaide Medical School, University of Adelaide, Adelaide, Australia
- Vascular Research Centre, Lifelong Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, Australia
- Department of Cardiology, Central Adelaide Local Health Network, Adelaide, Australia
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5
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Richards CE, Parker AE, Alfuhied A, McCann GP, Singh A. The role of 4-dimensional flow in the assessment of bicuspid aortic valve and its valvulo-aortopathies. Br J Radiol 2022; 95:20220123. [PMID: 35852109 PMCID: PMC9793489 DOI: 10.1259/bjr.20220123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Bicuspid aortic valve is the most common congenital cardiac malformation and the leading cause of aortopathy and aortic stenosis in younger patients. Aortic wall remodelling secondary to altered haemodynamic flow patterns, changes in peak velocity, and wall shear stress may be implicated in the development of aortopathy in the presence of bicuspid aortic valve and dysfunction. Assessment of these parameters as potential predictors of disease severity and progression is thus desirable. The anatomic and functional information acquired from 4D flow MRI can allow simultaneous visualisation and quantification of the pathological geometric and haemodynamic changes of the aorta. We review the current clinical utility of haemodynamic quantities including velocity, wall sheer stress and energy losses, as well as visual descriptors such as vorticity and helicity, and flow direction in assessing the aortic valve and associated aortopathies.
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Affiliation(s)
- Caryl Elizabeth Richards
- Department of Cardiovascular Sciences, University of Leicester and the National Institute for Health Research Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Alex E Parker
- Leicester Medical School, University of Leicester, Leicester, UK
| | - Aseel Alfuhied
- Department of Cardiovascular Sciences, University of Leicester and the National Institute for Health Research Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Gerry P McCann
- Department of Cardiovascular Sciences, University of Leicester and the National Institute for Health Research Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
| | - Anvesha Singh
- Department of Cardiovascular Sciences, University of Leicester and the National Institute for Health Research Leicester Biomedical Research Centre, Glenfield Hospital, Leicester, UK
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6
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Gomez A, Wang Z, Xuan Y, Hope MD, Saloner DA, Guccione JM, Ge L, Tseng EE. Regional wall stress differences on tricuspid aortic valve-associated ascending aortic aneurysms. Interact Cardiovasc Thorac Surg 2022; 34:1115-1123. [PMID: 34718581 PMCID: PMC10634398 DOI: 10.1093/icvts/ivab269] [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: 02/15/2021] [Revised: 07/15/2021] [Accepted: 08/27/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Ascending thoracic aortic aneurysms (aTAAs) carry a risk of acute type A dissection. Elective repair guidelines are based on diameter, but complications often occur below diameter threshold. Biomechanically, dissection can occur when wall stress exceeds wall strength. Aneurysm wall stresses may better capture dissection risk. Our aim was to investigate patient-specific aTAA wall stresses associated with a tricuspid aortic valve (TAV) by anatomic region. METHODS Patients with aneurysm diameter ≥4.0 cm underwent computed tomography angiography. Aneurysm geometries were reconstructed and loaded to systemic pressure while taking prestress into account. Finite element analyses were conducted to obtain wall stress distributions. The 99th percentile longitudinal and circumferential stresses were determined at systole. Wall stresses between regions were compared using one-way analysis of variance with post hoc Tukey HSD for pairwise comparisons. RESULTS Peak longitudinal wall stresses on aneurysms (n = 204) were 326 [standard deviation (SD): 61.7], 246 (SD: 63.4) and 195 (SD: 38.7) kPa in sinuses of Valsalva, sinotubular junction (STJ) and ascending aorta (AscAo), respectively, with significant differences between AscAo and both sinuses (P < 0.001) and STJ (P < 0.001). Peak circumferential wall stresses were 416 (SD: 85.1), 501 (SD: 119) and 340 (SD: 57.6) kPa for sinuses, STJ and AscAo, respectively, with significant differences between AscAo and both sinuses (P < 0.001) and STJ (P < 0.001). CONCLUSIONS Circumferential and longitudinal wall stresses were greater in the aortic root than AscAo on aneurysm patients with a TAV. Aneurysm wall stress magnitudes and distribution relative to respective regional wall strength could improve understanding of aortic regions at greater risk of dissection in a particular patient.
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Affiliation(s)
- Axel Gomez
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Zhongjie Wang
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Yue Xuan
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Michael D Hope
- Department of Radiology, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - David A Saloner
- Department of Radiology, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Julius M Guccione
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Liang Ge
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Elaine E Tseng
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
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Xiao HJ, Zhan AL, Huang QW, Huang RG, Lin WH. Computed tomography angiography assessment of the degree of simple coarctation of the aorta and its relationship with surgical outcome: A retrospective analysis. Front Pediatr 2022; 10:1017455. [PMID: 36545667 PMCID: PMC9760797 DOI: 10.3389/fped.2022.1017455] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 11/21/2022] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE To investigate the correlation between the degree of aortic coarctation and surgical prognosis in infants with simple coarctation of the aorta (CoA) using computed tomography angiography (CTA). METHODS This study was a retrospective study. Twenty-seven infants with simple CoA who underwent surgical correction from January 2020 to June 2022 were enrolled. Aortic diameters were measured at five different levels and normalized to Z scores based on the square root of body surface area. The relevant data were collected and analyzed, and the predictors associated with surgical outcome were determined. RESULTS Patients were divided into the mild CoA group and the severe CoA group according to the severity of coarctation. The mechanical ventilation duration and the length of ICU stay in the mild CoA group were significantly lower than those in the severe CoA group. Multiple linear regression analyses revealed that the degree of aortic coarctation was a significant risk factor for a prolonged postoperative ICU stay. In addition, gestational age and age at operation were risk factors for a prolonged postoperative ICU stay. Correlation analysis showed that the degree of aortic coarctation correlated with the Z scores of the ascending aorta and postcoarctation aorta. CONCLUSION The degree of the CoA is an important predictor of surgical outcomes in infants with simple CoA and was significantly correlated with the ascending aorta and postcoarctation aorta Z scores. Therefore, preoperative CTA should be routinely performed to assess the degree of aortic coarctation and better identify risk factors.
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Affiliation(s)
- Hui-Jun Xiao
- Department of Radiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China
| | - A-Lai Zhan
- Department of Radiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China
| | - Qing-Wen Huang
- Department of Radiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China
| | - Rui-Gang Huang
- Department of Radiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China
| | - Wei-Hua Lin
- Department of Radiology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China
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Hu H, Liu Z, Chen G, Yuan D, Zheng T. Analysis of aortic wall stress and morphology in patients with type B aortic dissection. MEDICINE IN NOVEL TECHNOLOGY AND DEVICES 2021. [DOI: 10.1016/j.medntd.2021.100081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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9
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Temporal Trends and Outcomes of Elective Thoracic Aortic Repair and Acute Aortic Syndromes in Bicuspid Aortic Valves: Insights from a National Database. Cardiol Ther 2021; 10:531-545. [PMID: 34431068 PMCID: PMC8555072 DOI: 10.1007/s40119-021-00237-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 07/27/2021] [Indexed: 11/12/2022] Open
Abstract
Introduction There is paucity of data on the outcomes of hospitalization for bicuspid aortic valve (BAV)-related aortopathies. Methods We queried the NIS database (2012–2016) for hospitalizations for elective thoracic aortic repair or acute aortic syndrome (AAS) among those with BAV versus trileaflet aortic valve (TAV). Results Our analysis yielded 38,010 hospitalizations for elective aortic repair, of whom 34.4% had BAV, as well as 81,875 hospitalizations for thoracic AAS, of whom 1.1% had BAV. Hospitalizations for BAV were younger and had fewer comorbidities compared with their TAV counterparts. The number of hospitalizations for BAV during the observational period was unchanged. After propensity matching, elective aortic repair for BAV was associated with lower mortality (0.5% versus 1.7%, odds ratio = 0.28; 95% CI 1.5–0.50, p < 0.001), use of mechanical circulatory support, acute stroke, and shorter length of hospital stay compared with TAV. After propensity matching, AAS among those with BAV had a greater incidence of bleeding events, blood transfusion, cardiac tamponade, ventricular arrhythmias, and a longer length of hospital stay compared with TAV. Among those with BAV, predictors of lower mortality if undergoing elective aortic repair included larger hospitals and teaching hospitals. Predictors of higher mortality in patients with AAS included heart failure, chronic kidney disease, and coronary artery disease. Conclusion Data from a national database showed no change in the number of hospitalizations for BAV-related aortopathy, with relatively lower incidence of AAS. Compared with TAV, elective aortic repair for BAV is associated with lower mortality, while BAV-related AAS is associated with higher in-hospital complications. Supplementary Information The online version contains supplementary material available at 10.1007/s40119-021-00237-3.
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Subramaniam DR, Gutmark E, Andersen N, Nielsen D, Mortensen K, Gravholt C, Backeljauw P, Gutmark-Little I. Influence of Material Model and Aortic Root Motion in Finite Element Analysis of Two Exemplary Cases of Proximal Aortic Dissection. J Biomech Eng 2021; 143:014504. [PMID: 32793953 DOI: 10.1115/1.4048084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Indexed: 01/25/2023]
Abstract
The risk of type-A dissection is increased in subjects with connective tissue disorders and dilatation of the proximal aorta. The location and extents of vessel wall tears in these patients could be potentially missed during prospective imaging studies. The objective of this study is to estimate the distribution of systolic wall stress in two exemplary cases of proximal dissection using finite element analysis (FEA) and evaluate the sensitivity of the distribution to the choice of anisotropic material model and root motion. FEA was performed for predissection aortas, without prior knowledge of the origin and extents of vessel wall tear. The stress distribution was evaluated along the wall tear in the postdissection aortas. The stress distribution was compared for the Fung and Holzapfel models with and without root motion. For the subject with spiral dissection, peak stress coincided with the origin of the tear in the sinotubular junction. For the case with root dissection, maximum stress was obtained at the distal end of the tear. The FEA predicted tear pressure was 20% higher for the subject with root dissection as compared to the case with spiral dissection. The predicted tear pressure was higher (9-11%) for root motions up to 10 mm. The Holzapfel model predicted a tear pressure that was lower (8-15%) than the Fung model. The FEA results showed that both material response and root motion could potentially influence the predicted dissection pressure of the proximal aorta at least for conditions tested in this study.
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Affiliation(s)
| | - Ephraim Gutmark
- Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH 45221-0070
| | - Niels Andersen
- Department of Cardiology, Aalborg University Hospital, Aalborg 9100, Denmark
| | - Dorte Nielsen
- Department of Cardiology, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Kristian Mortensen
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, London WC1N 3JH, UK
| | - Claus Gravholt
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus 8200, Denmark
| | - Philippe Backeljauw
- Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | - Iris Gutmark-Little
- Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
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11
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Gomez A, Wang Z, Xuan Y, Wisneski AD, Hope MD, Saloner DA, Guccione JM, Ge L, Tseng EE. Wall Stress Distribution in Bicuspid Aortic Valve-Associated Ascending Thoracic Aortic Aneurysms. Ann Thorac Surg 2020; 110:807-814. [PMID: 32006475 PMCID: PMC8598319 DOI: 10.1016/j.athoracsur.2019.12.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 11/09/2019] [Accepted: 12/16/2019] [Indexed: 12/14/2022]
Abstract
BACKGROUND Bicuspid aortic valve-associated ascending thoracic aortic aneurysms (BAV-aTAAs) carry a risk of acute type A dissection. Biomechanically, dissection may occur when wall stress exceeds wall strength. Our aim was to develop patient-specific computational models of BAV-aTAAs to determine magnitudes of wall stress by anatomic regions. METHODS Patients with BAV-aTAA diameter greater than 4.5 cm (n = 41) underwent electrocardiogram-gated computed tomography angiography. Three-dimensional aneurysm geometries were reconstructed after accounting for prestress and loaded to systemic pressure. Finite element analyses were performed with fiber-embedded hyperelastic material model using LS-DYNA software (LSTC Inc, Livermore, CA) to obtain wall stress distributions. The 99th percentile longitudinal and circumferential stresses were determined at systole. RESULTS The 99th percentile longitudinal wall stresses for BAV-aTAAs at sinuses of Valsalva, sinotubular junction (STJ), and ascending aorta were 361 ± 59.8 kPa, 295 ± 67.2 kPa, and 224 ± 37.6 kPa, respectively, with significant differences in ascending aorta vs sinuses (P< 1 × 10-13) and STJ (P < 1 × 10-6). The 99th percentile circumferential wall stresses were 474 ± 88.2 kPa, 634 ± 181.9 kPa, and 381 ± 54.0 kPa for sinuses, the STJ, and the ascending aorta, respectively, with significant differences in the ascending aorta vs sinuses (P = .002) and STJ (P < 1 × 10-13). CONCLUSIONS Wall stresses, both circumferential and longitudinal, were greater in the aortic root, sinuses, and STJ than in the ascending aorta on BAV-aTAAs. These results fill a fundamental knowledge gap regarding biomechanical stress distribution in BAV-aTAA patients, which when related to wall strength may provide prognostication of aTAA dissection risk by patient-specific modeling.
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Affiliation(s)
- Axel Gomez
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Zhongjie Wang
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Yue Xuan
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Andrew D Wisneski
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Michael D Hope
- Department of Radiology, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - David A Saloner
- Department of Radiology, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Julius M Guccione
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Liang Ge
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Elaine E Tseng
- Department of Surgery, University of California, San Francisco and San Francisco VA Medical Center, San Francisco, California.
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12
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Sundström E, Jonnagiri R, Gutmark-Little I, Gutmark E, Critser P, Taylor MD, Tretter JT. Hemodynamics and tissue biomechanics of the thoracic aorta with a trileaflet aortic valve at different phases of valve opening. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2020; 36:e3345. [PMID: 32359198 DOI: 10.1002/cnm.3345] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 02/17/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
In a normal cardiac cycle, the trileaflet aortic valve opening is progressive, which correlates with the phasic blood flow. Therefore, we aimed to determine the impact of including an anatomically accurate reconstructed trileaflet aortic valve within a fluid-structure interaction (FSI) simulation model and determine the cyclical hemodynamic forces imposed on the thoracic aortic walls from aortic valve opening to closure. A pediatric patient with a normal trileaflet valve was recruited. Using the Cardiac Magnetic Resonance Data (CMR), a 3D model of the aortic valve and thoracic aorta was reconstructed. FSI simulations were employed to assess the tissue stress during a cardiac cycle as the result of changes in the valve opening. The blood flow was simulated as a mixture of blood plasma and red blood cells to account for non-Newtonian effects. The computation was validated with phase-contrast CMR. Windkessel boundary conditions were employed to ensure physiological pressures during the cardiac cycle. The leaflets' dynamic motion during the cardiac cycle was defined with an analytic grid velocity function. At the beginning of the valve opening a thin jet is developing. From mid-open towards full opening the stress level increases where the jet impinges the convex wall. At peak systole two counter-rotating Dean-like vortex cores manifest in the ascending aorta, which correlates with increased integrated mean stress levels. An accurate trileaflet aortic valve is needed for capturing of both primary and secondary flow features that impact the forces on the thoracic aorta wall. Omitting the aortic valve underestimates the biomechanical response.
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Affiliation(s)
- Elias Sundström
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, Cincinnati, Ohio, USA
| | - Raghuvir Jonnagiri
- Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Iris Gutmark-Little
- Division of Endocrine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Ephraim Gutmark
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, Cincinnati, Ohio, USA
- Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Paul Critser
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Michael D Taylor
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Justin T Tretter
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
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13
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Krupiński M, Irzyk M, Moczulski Z, Banyś R, Urbańczyk-Zawadzka M. Morphometric evaluation of aortic coarctation and collateral circulation using computed tomography in the adult population. Acta Radiol 2020; 61:605-612. [PMID: 31581781 DOI: 10.1177/0284185119877328] [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] [Indexed: 11/17/2022]
Abstract
Background Analysis of morphometric details of aortic coarctation and collateral circulation using computed tomography (CT) and its impact on clinical symptoms is a perspective which is missing in the published literature. Purpose To perform CT-based qualitative and quantitative evaluation of aortic coarctation and collateral circulation with reference to clinical symptoms. Material and Methods The study comprised 2022 patients who underwent CT angiography. If aortic coarctation was seen, the patients underwent evaluation of its anatomy and associated clinical symptoms. Results Aortic coarctation was found in 33 patients. Follow-up (median 2476 days; range 1692–3543) was performed in 31 (94%) individuals. In this group (median age 42 years; range 30–52.5 years), median stenosis at the site of coarctation was 70% (range 58–85%) of the lumen area, with 17 (55%) patients presenting with significant (≥70%) stenosis. Patients with significant stenosis had a greater right and left internal mammary artery diameter ( P = 0.0070 and P = 0.0114, respectively) than those with mild stenosis. Patients with significant coarctation stenosis revealed hypertension and headache more commonly than those with mild stenosis (17 vs. 9, P = 0.01 and 10 vs. 2, P = 0.02), respectively. In patients who underwent intervention, a decrease in prevalence of hypertension (19 vs. 0, P = 0.008) and headache (12 vs. 3, P = 0.010) were observed in the follow-up. Conclusion CT enables quantitative and qualitative evaluation of aortic coarctation anatomy, including stenosis at the site of coarctation, and collateral circulation. In adult patients with aortic coarctation, the prevalence of hypertension and headache is related to the degree of stenosis at the site of coarctation and decreases after intervention.
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Affiliation(s)
- Maciej Krupiński
- Department of Radiology and Diagnostic Imaging, John Paul II Hospital, Krakow, Poland
| | - Małgorzata Irzyk
- Department of Radiology and Diagnostic Imaging, John Paul II Hospital, Krakow, Poland
| | - Zbigniew Moczulski
- Department of Radiology and Diagnostic Imaging, John Paul II Hospital, Krakow, Poland
| | - Robert Banyś
- Department of Radiology and Diagnostic Imaging, John Paul II Hospital, Krakow, Poland
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14
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Statistical Shape Analysis of Ascending Thoracic Aortic Aneurysm: Correlation between Shape and Biomechanical Descriptors. J Pers Med 2020; 10:jpm10020028. [PMID: 32331429 PMCID: PMC7354467 DOI: 10.3390/jpm10020028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/14/2020] [Accepted: 04/17/2020] [Indexed: 12/21/2022] Open
Abstract
An ascending thoracic aortic aneurysm (ATAA) is a heterogeneous disease showing different patterns of aortic dilatation and valve morphologies, each with distinct clinical course. This study aimed to explore the aortic morphology and the associations between shape and function in a population of ATAA, while further assessing novel risk models of aortic surgery not based on aortic size. Shape variability of n = 106 patients with ATAA and different valve morphologies (i.e., bicuspid versus tricuspid aortic valve) was estimated by statistical shape analysis (SSA) to compute a mean aortic shape and its deformation. Once the computational atlas was built, principal component analysis (PCA) allowed to reduce the complex ATAA anatomy to a few shape modes, which were correlated to shear stress and aortic strain, as determined by computational analysis. Findings demonstrated that shape modes are associated to specific morphological features of aneurysmal aorta as the vessel tortuosity and local bulging of the ATAA. A predictive model, built with principal shape modes of the ATAA wall, achieved better performance in stratifying surgically operated ATAAs versus monitored ATAAs, with respect to a baseline model using the maximum aortic diameter. Using current imaging resources, this study demonstrated the potential of SSA to investigate the association between shape and function in ATAAs, with the goal of developing a personalized approach for the treatment of the severity of aneurysmal aorta.
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15
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Sundström E, Jonnagiri R, Gutmark-Little I, Gutmark E, Critser P, Taylor MD, Tretter JT. Effects of Normal Variation in the Rotational Position of the Aortic Root on Hemodynamics and Tissue Biomechanics of the Thoracic Aorta. Cardiovasc Eng Technol 2019; 11:47-58. [PMID: 31701357 DOI: 10.1007/s13239-019-00441-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/30/2019] [Indexed: 01/04/2023]
Abstract
PURPOSE Variation in the rotational position of the aortic root relative to the left ventricle is present in normal trileaflet aortic valves. Its impact on the resulting fluid mechanics of blood flow in the thoracic aorta and structural mechanics in the aortic wall are unknown. We aimed to determine the regional hemodynamic and biomechanical differences in different rotational positions of the normal aortic root (clockwise, central, and counterclockwise positions). METHOD Cardiac magnetic resonance imaging (CMR) data was acquired from a normal pediatric patient. These were used for reconstruction of the aortic valve and thoracic aorta 3D model. Fluid-structure interaction (FSI) simulations were employed to study the influence of the root rotation with a central position as compared to observed extreme variations. Patient-specific phase-encoding CMR data were used to assess the validity of computed blood flow. The 3D FSI model was coupled with Windkessel boundary conditions that were tuned for physiological pressures. A grid velocity function was adopted for the valve motion during the systolic period. RESULTS The largest wall shear stress level is detected in the clockwise positioned aortic root at the sinutubular junction. Two counter-rotating vortex cores are formed within the aortic root of both the central and extreme root configurations, however, in the clockwise root the vortex system becomes more symmetric. This also coincides with more entrainment of the valve jet and more turbulence production along the shear layer. CONCLUSION A clockwise rotational position of the aortic root imparts an increased wall shear stress at the sinutubular junction and proximal ascending aorta in comparison to other root rotation positions. This may pose increased risk for dilation of the sinutubular junction and ascending aorta in the patient with a clockwise positioned aortic root compared to other normal positional configurations.
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Affiliation(s)
- Elias Sundström
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, Cincinnati, OH, 45267, USA.
| | - Raghuvir Jonnagiri
- Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Iris Gutmark-Little
- Division of Endocrine, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Ephraim Gutmark
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati, Cincinnati, OH, 45267, USA.,Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Paul Critser
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Michael D Taylor
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA.,Department of Pediatrics, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Justin T Tretter
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA.,Department of Pediatrics, University of Cincinnati, Cincinnati, OH, 45267, USA
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16
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Borger MA, Fedak PWM, Stephens EH, Gleason TG, Girdauskas E, Ikonomidis JS, Khoynezhad A, Siu SC, Verma S, Hope MD, Cameron DE, Hammer DF, Coselli JS, Moon MR, Sundt TM, Barker AJ, Markl M, Della Corte A, Michelena HI, Elefteriades JA. The American Association for Thoracic Surgery consensus guidelines on bicuspid aortic valve-related aortopathy: Full online-only version. J Thorac Cardiovasc Surg 2019; 156:e41-e74. [PMID: 30011777 DOI: 10.1016/j.jtcvs.2018.02.115] [Citation(s) in RCA: 162] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 01/17/2018] [Accepted: 02/12/2018] [Indexed: 12/11/2022]
Abstract
Bicuspid aortic valve disease is the most common congenital cardiac disorder, being present in 1% to 2% of the general population. Associated aortopathy is a common finding in patients with bicuspid aortic valve disease, with thoracic aortic dilation noted in approximately 40% of patients in referral centers. Several previous consensus statements and guidelines have addressed the management of bicuspid aortic valve-associated aortopathy, but none focused entirely on this disease process. The current guidelines cover all major aspects of bicuspid aortic valve aortopathy, including natural history, phenotypic expression, histology and molecular pathomechanisms, imaging, indications for surgery, surveillance, and follow-up, and recommendations for future research. It is intended to provide clinicians with a current and comprehensive review of bicuspid aortic valve aortopathy and to guide the daily management of these complex patients.
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Affiliation(s)
- Michael A Borger
- Leipzig Heart Center, Cardiac Surgery, University of Leipzig, Leipzig, Germany.
| | - Paul W M Fedak
- Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | - Thomas G Gleason
- Division of Cardiac Surgery, Department of Cardiothoracic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pa
| | - Evaldas Girdauskas
- Department of Cardiovascular Surgery, University Heart Center Hamburg, Hamburg, Germany
| | - John S Ikonomidis
- Division of Cardiothoracic Surgery, University of North Carolina, Chapel Hill, NC
| | - Ali Khoynezhad
- Memorial Care Heart and Vascular Institute, Memorial Care Long Beach Medical Center, Long Beach, Calif
| | - Samuel C Siu
- Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Subodh Verma
- Department of Cardiac Surgery, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Michael D Hope
- San Francisco (UCSF) Department of Radiology & Biomedical Imaging, University of California, San Francisco, Calif
| | - Duke E Cameron
- Department of Cardiac Surgery, Massachusetts General Hospital, Boston, Mass
| | - Donald F Hammer
- Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio
| | - Joseph S Coselli
- Division of Cardiothoracic Surgery, Texas Heart Institute, Baylor College of Medicine, Houston, Tex
| | - Marc R Moon
- Section of Cardiac Surgery, Washington University School of Medicine, St Louis, Mo
| | - Thoralf M Sundt
- Division of Cardiac Surgery, Massachusetts General Hospital, Boston, Mass
| | - Alex J Barker
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, Ill
| | - Michael Markl
- Departments of Radiology and Biomedical Engineering, Feinberg School of Medicine, Northwestern University, Chicago, Ill
| | | | | | - John A Elefteriades
- Department of Cardiothoracic Surgery, Yale University School of Medicine, New Haven, Conn
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17
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Yin 殷晓科 X, Wanga S, Fellows AL, Barallobre-Barreiro J, Lu R, Davaapil H, Franken R, Fava M, Baig F, Skroblin P, Xing Q, Koolbergen DR, Groenink M, Zwinderman AH, Balm R, de Vries CJM, Mulder BJM, Viner R, Jahangiri M, Reinhardt DP, Sinha S, de Waard V, Mayr M. Glycoproteomic Analysis of the Aortic Extracellular Matrix in Marfan Patients. Arterioscler Thromb Vasc Biol 2019; 39:1859-1873. [PMID: 31315432 PMCID: PMC6727943 DOI: 10.1161/atvbaha.118.312175] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Supplemental Digital Content is available in the text. Marfan syndrome (MFS) is caused by mutations in FBN1 (fibrillin-1), an extracellular matrix (ECM) component, which is modified post-translationally by glycosylation. This study aimed to characterize the glycoproteome of the aortic ECM from patients with MFS and relate it to aortopathy.
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Affiliation(s)
- Xiaoke Yin 殷晓科
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Shaynah Wanga
- Department of Medical Biochemistry, Amsterdam Cardiovascular Sciences (S.W., C.J.M.d.V., V.d.W.), Amsterdam UMC, University of Amsterdam, the Netherlands.,Department of Cardiology (S.W., R.F., M.G., B.J.M.M.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Adam L Fellows
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Javier Barallobre-Barreiro
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Ruifang Lu
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Hongorzul Davaapil
- Department of Medicine, Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, United Kingdom (H.D., S.S.)
| | - Romy Franken
- Department of Cardiology (S.W., R.F., M.G., B.J.M.M.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Marika Fava
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Ferheen Baig
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Philipp Skroblin
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - Qiuru Xing
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
| | - David R Koolbergen
- Department of Cardiothoracic Surgery (D.R.K.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Maarten Groenink
- Department of Cardiology (S.W., R.F., M.G., B.J.M.M.), Amsterdam UMC, University of Amsterdam, the Netherlands.,Department of Radiology (M.G.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Aeilko H Zwinderman
- Department of Clinical Epidemiology, Biostatistics and Bioinformatics (A.H.Z.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Ron Balm
- Department of Surgery (R.B.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Carlie J M de Vries
- Department of Medical Biochemistry, Amsterdam Cardiovascular Sciences (S.W., C.J.M.d.V., V.d.W.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Barbara J M Mulder
- Department of Cardiology (S.W., R.F., M.G., B.J.M.M.), Amsterdam UMC, University of Amsterdam, the Netherlands.,Netherlands Heart Institute, Utrecht (B.J.M.M.)
| | - Rosa Viner
- Thermo Fisher Scientific, San Jose, CA (R.V.)
| | | | - Dieter P Reinhardt
- Faculty of Medicine, Department of Anatomy and Cell Biology and Faculty of Dentistry, McGill University, Montreal, Canada (D.P.R.)
| | - Sanjay Sinha
- Department of Medicine, Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, United Kingdom (H.D., S.S.)
| | - Vivian de Waard
- Department of Medical Biochemistry, Amsterdam Cardiovascular Sciences (S.W., C.J.M.d.V., V.d.W.), Amsterdam UMC, University of Amsterdam, the Netherlands
| | - Manuel Mayr
- From the King's British Heart Foundation Centre, King's College London, United Kingdom (X.Y., A.L.F., J.B.-B., R.L., M.F., F.B., P.S., Q.X., M.M.)
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Cavinato C, Molimard J, Curt N, Campisi S, Orgéas L, Badel P. Does the Knowledge of the Local Thickness of Human Ascending Thoracic Aneurysm Walls Improve Their Mechanical Analysis? Front Bioeng Biotechnol 2019; 7:169. [PMID: 31380360 PMCID: PMC6646470 DOI: 10.3389/fbioe.2019.00169] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/02/2019] [Indexed: 12/22/2022] Open
Abstract
Ascending thoracic aortic aneurysm (ATAA) ruptures are life threatening phenomena which occur in local weaker regions of the diseased aortic wall. As ATAAs are evolving pathologies, their growth represents a significant local remodeling and degradation of the microstructural architecture and thus their mechanical properties. To address the need for deeper study of ATAAs and their failure, it is required to analyze the mechanical behavior at the sub-millimeter scale by making use of accurate geometrical and kinematical measurements during their deformation. For this purpose, we propose a novel methodology that combined an accurate tool for thickness distribution measurement of the arterial wall, digital image correlation to assess local strain fields and bulge inflation to characterize the physiological and failure response of flat unruptured human ATAA specimens. The analysis of the heterogeneity of the local thickness and local physiological stress and strain was carried out for each investigated subject. At the subject level, our results state the presence of a non-consistent relationship between the local wall thickness and the local physiological strain field and high heterogeneity of the variables. At the inter-subject level, thicknesses were studied in relation to physiological strain and stress and load at rupture. The rupture pressure was correlated with neither the average thickness nor the lowest thickness of the specimens. Our results confirm that intrinsic material strength (hence structure) differs a lot from a subject to another and even within the same subject.
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Affiliation(s)
- Cristina Cavinato
- Mines Saint-Etienne, Centre CIS, INSERM, U 1059 Sainbiose, Univ Lyon, Univ Jean Monnet, Saint-Etienne, France
| | - Jerome Molimard
- Mines Saint-Etienne, Centre CIS, INSERM, U 1059 Sainbiose, Univ Lyon, Univ Jean Monnet, Saint-Etienne, France
| | - Nicolas Curt
- Mines Saint-Etienne, Centre CIS, INSERM, U 1059 Sainbiose, Univ Lyon, Univ Jean Monnet, Saint-Etienne, France
| | - Salvatore Campisi
- Department of CardioVascular Surgery, CHU Hôpital Nord Saint-Etienne, Saint-Etienne, France
| | - Laurent Orgéas
- UMR 5521, Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR Lab, Grenoble, France
| | - Pierre Badel
- Mines Saint-Etienne, Centre CIS, INSERM, U 1059 Sainbiose, Univ Lyon, Univ Jean Monnet, Saint-Etienne, France
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19
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Cosentino F, Scardulla F, D'Acquisto L, Agnese V, Gentile G, Raffa G, Bellavia D, Pilato M, Pasta S. Computational modeling of bicuspid aortopathy: Towards personalized risk strategies. J Mol Cell Cardiol 2019; 131:122-131. [PMID: 31047985 DOI: 10.1016/j.yjmcc.2019.04.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/09/2019] [Accepted: 04/26/2019] [Indexed: 11/18/2022]
Abstract
This paper describes current advances on the application of in-silico for the understanding of bicuspid aortopathy and future perspectives of this technology on routine clinical care. This includes the impact that artificial intelligence can provide to develop computer-based clinical decision support system and that wearable sensors can offer to remotely monitor high-risk bicuspid aortic valve (BAV) patients. First, we discussed the benefit of computational modeling by providing tangible examples of in-silico software products based on computational fluid-dynamic (CFD) and finite-element method (FEM) that are currently transforming the way we diagnose and treat cardiovascular diseases. Then, we presented recent findings on computational hemodynamic and structural mechanics of BAV to highlight the potentiality of patient-specific metrics (not-based on aortic size) to support the clinical-decision making process of BAV-associated aneurysms. Examples of BAV-related personalized healthcare solutions are illustrated.
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Affiliation(s)
- Federica Cosentino
- Promozione della Salute, Materno-Infantile, di Medicina Interna e Specialistica di Eccellenza "G. D'Alessandro", University of Palermo, Piazza delle Cliniche, n.2, 90128 Palermo, Italy; Fondazione Ri.MED, Via Bandiera n.11, 90133 Palermo, Italy
| | - Francesco Scardulla
- Department of Engineering, University of Palermo, Viale delle Scienze Ed.8, 90128 Palermo, Italy
| | - Leonardo D'Acquisto
- Department of Engineering, University of Palermo, Viale delle Scienze Ed.8, 90128 Palermo, Italy
| | - Valentina Agnese
- Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy
| | - Giovanni Gentile
- Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy
| | - Giuseppe Raffa
- Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy
| | - Diego Bellavia
- Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy
| | - Michele Pilato
- Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy
| | - Salvatore Pasta
- Fondazione Ri.MED, Via Bandiera n.11, 90133 Palermo, Italy; Department for the Treatment and Study of Cardiothoracic Diseases and Cardiothoracic Transplantation, IRCCS-ISMETT, Via Tricomi n.5, 90127 Palermo, Italy.
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20
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Abstract
UNLABELLED AimWe investigated dimensions and elasticity of whole aorta in patients with bicuspid aortic valve and influence of valve phenotype. METHOD The study group included 44 patients and 42 controls. Patients were divided into groups according to the type of valve opening as horizontal - fusion between right and left coronary cusps - and vertical - fusion between right-non-coronary cusps; according to age they were divided into younger (5-10 years) and older patients (11-16 years). Our study did not include valve phenotype with fusion between left and non-coronary cusps. Systolic-diastolic diameters of aortic annulus, sinus valsalva, sinutubular junction, arcus, and ascending-descending and abdominal aorta were measured and z-scores were obtained. Aortic strain, distensibility, and stiffness index were calculated. Flow-mediated dilatation of brachial artery was studied. RESULTS z-Scores at annulus, sinus valsalva, sinutubular junction, and ascending aorta were higher in study patients (p=0.001, p=0.0001, p=0.0001, p=0.0001, respectively). z-Scores of sinus valsalva and sinotubular junction were higher in the horizontal group than in the vertical group (p=0.006, p=0.023, respectively). z-Score was over +2 in 51% of patients with horizontal morphology and 33% of patients with vertical morphology (p=0.0001). Ascending aorta was more distensible and less stiff in the study group (11.3±5.63 versus 7.91±4.5, p=0.002; 4.76±3.60 versus 6.19±3.44 cm2.dyn-1.10-6, p=0.033, respectively). Stiffness index of ascending, arcus, and abdominal aorta were higher in the horizontal group (p=0.004, p=0.038, p=0.006, respectively). Ascending aorta was more distensible and less stiff in the younger group (p=0.007, p=0.027, respectively) but did not differ in the older group compared with the control group. CONCLUSION Aortic dimensions are enlarged in patients with bicuspid aortic valve starting from childhood, suggesting the presence of generalised aortopathy. Aortic elasticity is increased at young age and decreased with age.
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21
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Mendez V, Di Giuseppe M, Pasta S. Comparison of hemodynamic and structural indices of ascending thoracic aortic aneurysm as predicted by 2-way FSI, CFD rigid wall simulation and patient-specific displacement-based FEA. Comput Biol Med 2018; 100:221-229. [DOI: 10.1016/j.compbiomed.2018.07.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 10/28/2022]
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22
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Hirata Y, Aoki H, Shojima T, Takagi K, Takaseya T, Akasu K, Tobinaga S, Fukumoto Y, Tanaka H. Activation of the AKT Pathway in the Ascending Aorta With Bicuspid Aortic Valve. Circ J 2018; 82:2485-2492. [PMID: 30089758 DOI: 10.1253/circj.cj-17-1465] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Dilatation of the ascending aorta affects those patients with bicuspid aortic valve (BAV), even after valvular surgery, possibly due to tissue fragility. The goal of the study was the molecular characterization of aorta with BAV compared to that with normal tricuspid aortic valve (TAV). Methods and Results: The subjects were patients who underwent surgery for aortic valve stenosis in 2013 and 2014. Nine patients with BAV and 13 with TAV were examined. There was no difference in the clinical characteristics or grade of aortic valve stenosis, but the diameters of the ascending aorta were significantly higher in the BAV group. The ascending aortic specimens were subjected to transcriptome analyses, which revealed the changes in receptor tyrosine kinase (RTK) pathway-related genes between TAV and BAV samples. Immunohistochemical study revealed higher staining of phosphorylated AKT (pAKT) in the media of the ascending aorta in the BAV group, regardless of the size of ascending aorta, whereas total AKT did not show such a difference. Immunofluorescence staining revealed the AKT activation was mainly in the medial vascular smooth muscle cells. CONCLUSIONS The results showed that the RTK-AKT pathway in the medial layer of the ascending aorta is activated in aortae with BAV. Activation of this pathway may be associated with fragility and dilatation of the ascending aorta with BAV.
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Affiliation(s)
- Yuichiro Hirata
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Hiroki Aoki
- Cardiovascular Research Institute, Kurume University
| | - Takahiro Shojima
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Kazuyoshi Takagi
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Tohru Takaseya
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Kohji Akasu
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Satoru Tobinaga
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
| | - Yoshihiro Fukumoto
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kurume University School of Medicine
| | - Hiroyuki Tanaka
- Division of Cardiovascular Surgery, Department of Surgery, Kurume University School of Medicine
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23
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Plonek T, Berezowski M, Kurcz J, Podgorski P, Sąsiadek M, Rylski B, Mysiak A, Jasinski M. The evaluation of the aortic annulus displacement during cardiac cycle using magnetic resonance imaging. BMC Cardiovasc Disord 2018; 18:154. [PMID: 30064358 PMCID: PMC6069890 DOI: 10.1186/s12872-018-0891-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 07/18/2018] [Indexed: 01/16/2023] Open
Abstract
Background The stress in the ascending aorta results from many biomechanical factors including the geometry of the vessel and its maximum dimensions, arterial blood pressure and longitudinal systolic stretching due to heart motion. The stretching of the ascending aorta resulting from the longitudinal displacement of the aortic annulus during the heart cycle has not been examined in the general population so far. The aim of the study is to evaluate this parameter using cardiovascular magnetic resonance (CMR) imaging in the general population in all age groups. Methods The cardiac magnetic resonance images of 73 patients were evaluated. The maximum distance to which the ventriculo-aortic junction was pulled by the contracting heart (LDAA – longitudinal displacement of the aortic annulus) was measured in the cine coronal sequences. Moreover, the maximum dimensions of the aortic root and the ascending aorta were assessed. Results The LDAA value was on average 11.6 ± 2.9 mm (range: 3-19 mm; 95% CI: 10.9–12.3 mm) and did not differ between males and females (11.8 ± 2.9 mm vs. 11.2 ± 2.9 mm, p = .408). The diameter of the ascending aorta was 32 ± 6.3 mm (range: 20-57 mm). The maximal dimension of the aortic root was 35 ± 5.1 mm (range: 18-42 mm). There was a statistically significant negative correlation between the LDAA and the age of patients (r = −.38, p = .001). There was no significant correlation between the LDAA and aortic root dimension (r = .1, p = .409) and between the LDAA and diameter of the ascending aorta (r = .16, p = .170). Conclusions Human aortic root and ascending aorta are significantly stretched during systole and the distance to which the aorta is stretched decreases with age. The measurement of the longitudinal displacement of the aortic annulus using the CMR is feasible and reproducible.
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Affiliation(s)
- Tomasz Plonek
- Department of Cardiac Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland. .,Department of Cardio-Thoracic Surgery, Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands.
| | - Mikolaj Berezowski
- Department of Cardiac Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland
| | - Jacek Kurcz
- Department of General and Interventional Radiology and Neuroradiology, Wroclaw Medical University, Wroclaw, Poland
| | - Przemyslaw Podgorski
- Department of General and Interventional Radiology and Neuroradiology, Wroclaw Medical University, Wroclaw, Poland
| | - Marek Sąsiadek
- Department of General and Interventional Radiology and Neuroradiology, Wroclaw Medical University, Wroclaw, Poland
| | - Bartosz Rylski
- Department of Cardio-vascular Surgery, Heart Centre Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andrzej Mysiak
- Department of Cardiology, Wroclaw Medical University, Wroclaw, Poland
| | - Marek Jasinski
- Department of Cardiac Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland
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Zhao Q, Shi K, Yang ZG, Diao KY, Xu HY, Liu X, Guo YK. Predictors of aortic dilation in patients with coarctation of the aorta: evaluation with dual-source computed tomography. BMC Cardiovasc Disord 2018; 18:124. [PMID: 29929466 PMCID: PMC6013956 DOI: 10.1186/s12872-018-0863-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 06/12/2018] [Indexed: 02/05/2023] Open
Abstract
Background Coarctation of aorta (CoA) may progressively develop aortic dilation at other site of the aorta and can lead to fatal aortic diseases. We aimed to evaluate the occurrence of aortic dilation and related predictors in patients with CoA using dual-source computed tomography (DSCT). Methods Fifty-three patients with CoA identified by DSCT were retrospectively reviewed. Aortic diameters were measured at six different levels and standardized as z-scores based on the square root of body surface area. Coarctation site–diaphragm ratio (CDR) was used to describe the degree of narrowing. A total of 26 patients were included in mild group (CDR > 50%) and 27 in severe group (CDR < 50%) according to the severity of coarctation. Student’s t-test and Spearman correlation coefficients, univariate and multivariable logistic regression analyses were used to assess the risk factors including age, degree of narrowing and other malformations for aortic dilation. Results Severe group had significantly larger z-scores of ascending aorta (2.41 ± 0.39 vs. 2.10 ± 0.57, p < 0.05) and post-coarctation aorta (2.17 ± 0.48 vs. 1.68 ± 0.43, p < 0.001) compared with mild group. Degree of coarctation was associated with the z-scores of the ascending aorta (r = − 0.356, p < 0.05) and post-coarctation aorta (r = − 0.414, p < 0.05). Collateral circulation was related to the z-scores of ascending aorta (r = 0.375, p < 0.05). Increased severity of coarctation was independent predictor of ascending (odds ratio 7.46; 95% CI 1.19–46.76; p < 0.05) and post-coarctation aortic dilation(odds ratio 8.42; 95% CI 1.84–38.56; p < 0.05). Conclusions Ascending and post-coarctation aortic diameters or dilations were both associated with the degree of coarctation. By comprehensively evaluating the aortic diameters and associated malformations including collateral circulation, DSCT can aid in stratification of risk for aortic dilation in patients with CoA. Electronic supplementary material The online version of this article (10.1186/s12872-018-0863-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Qin Zhao
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China
| | - Ke Shi
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China
| | - Zhi-Gang Yang
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China.
| | - Kai-Yue Diao
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China
| | - Hua-Yan Xu
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China
| | - Xi Liu
- Department of Radiology, West China Hospital, Sichuan University, 37# Guo Xue Xiang, Chengdu, 610041, Sichuan, China
| | - Ying-Kun Guo
- Department of Radiology, West China Second University Hospital, Sichuan University, 20# Section 3 South Renmin Road, Chengdu, 610041, Sichuan, China.
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Plonek T, Zak M, Rylski B, Berezowski M, Czerny M, Beyersdorf F, Jasinski M, Filipiak J. Wall stress correlates with intimal entry tear localization in Type A aortic dissection†. Interact Cardiovasc Thorac Surg 2018; 27:797-801. [DOI: 10.1093/icvts/ivy158] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 04/10/2018] [Indexed: 01/12/2023] Open
Affiliation(s)
- Tomasz Plonek
- Department of Cardiac Surgery, Wroclaw Medical University, Wroclaw, Poland
| | - Malgorzata Zak
- Department of Biomedical Engineering, Mechatronics and Theory of Mechanisms, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Bartosz Rylski
- Department of Cardiovascular Surgery, Faculty of Medicine, Heart Centre Freiburg University, University of Freiburg, Freiburg, Germany
| | - Mikolaj Berezowski
- Department of Cardiac Surgery, Wroclaw Medical University, Wroclaw, Poland
| | - Martin Czerny
- Department of Cardiovascular Surgery, Faculty of Medicine, Heart Centre Freiburg University, University of Freiburg, Freiburg, Germany
| | - Friedhelm Beyersdorf
- Department of Cardiovascular Surgery, Faculty of Medicine, Heart Centre Freiburg University, University of Freiburg, Freiburg, Germany
| | - Marek Jasinski
- Department of Cardiac Surgery, Wroclaw Medical University, Wroclaw, Poland
| | - Jaroslaw Filipiak
- Department of Biomedical Engineering, Mechatronics and Theory of Mechanisms, Wroclaw University of Science and Technology, Wroclaw, Poland
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Sophocleous F, Milano EG, Pontecorboli G, Chivasso P, Caputo M, Rajakaruna C, Bucciarelli-Ducci C, Emanueli C, Biglino G. Enlightening the Association between Bicuspid Aortic Valve and Aortopathy. J Cardiovasc Dev Dis 2018; 5:E21. [PMID: 29671812 PMCID: PMC6023468 DOI: 10.3390/jcdd5020021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 04/16/2018] [Accepted: 04/16/2018] [Indexed: 12/11/2022] Open
Abstract
Bicuspid aortic valve (BAV) patients have an increased incidence of developing aortic dilation. Despite its importance, the pathogenesis of aortopathy in BAV is still largely undetermined. Nowadays, intense focus falls both on BAV morphology and progression of valvular dysfunction and on the development of aortic dilation. However, less is known about the relationship between aortic valve morphology and aortic dilation. A better understanding of the molecular pathways involved in the homeostasis of the aortic wall, including the extracellular matrix, the plasticity of the vascular smooth cells, TGFβ signaling, and epigenetic dysregulation, is key to enlighten the mechanisms underpinning BAV-aortopathy development and progression. To date, there are two main theories on this subject, i.e., the genetic and the hemodynamic theory, with an ongoing debate over the pathogenesis of BAV-aortopathy. Furthermore, the lack of early detection biomarkers leads to challenges in the management of patients affected by BAV-aortopathy. Here, we critically review the current knowledge on the driving mechanisms of BAV-aortopathy together with the current clinical management and lack of available biomarkers allowing for early detection and better treatment optimization.
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Affiliation(s)
- Froso Sophocleous
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
| | - Elena Giulia Milano
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Department of Medicine, Division of Cardiology, University of Verona, 37100 Verona, Italy.
| | - Giulia Pontecorboli
- Structural Interventional Cardiology Division, Department of Experimental and Clinical Medicine, University of Florence, 50100 Florence, Italy.
| | - Pierpaolo Chivasso
- Cardiac Surgery, University Hospitals Bristol, NHS Foundation Trust, Bristol BS2 8HW, UK.
| | - Massimo Caputo
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Cardiac Surgery, University Hospitals Bristol, NHS Foundation Trust, Bristol BS2 8HW, UK.
| | - Cha Rajakaruna
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Cardiac Surgery, University Hospitals Bristol, NHS Foundation Trust, Bristol BS2 8HW, UK.
| | - Chiara Bucciarelli-Ducci
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Cardiac Surgery, University Hospitals Bristol, NHS Foundation Trust, Bristol BS2 8HW, UK.
| | - Costanza Emanueli
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Cardiac Surgery, University Hospitals Bristol, NHS Foundation Trust, Bristol BS2 8HW, UK.
- National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK.
| | - Giovanni Biglino
- Bristol Heart Institute, Bristol Medical School, University of Bristol, Bristol BS2 89HW, UK.
- Cardiorespiratory Unit, Great Ormond Street Hospital for Children, NHS Foundation Trust, London WC1N 3JH, UK.
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27
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Doyle BJ, Norman PE, Hoskins PR, Newby DE, Dweck MR. Wall Stress and Geometry of the Thoracic Aorta in Patients With Aortic Valve Disease. Ann Thorac Surg 2018; 105:1077-1085. [DOI: 10.1016/j.athoracsur.2017.11.061] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 11/07/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
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28
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Zhang L, Wang C, Xi Z, Li D, Xu Z. Mercaptoethanol Protects the Aorta from Dissection by Inhibiting Oxidative Stress, Inflammation, and Extracellular Matrix Degeneration in a Mouse Model. Med Sci Monit 2018; 24:1802-1812. [PMID: 29589594 PMCID: PMC5887686 DOI: 10.12659/msm.905151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background The aims of this study were to investigate the effects of mercaptoethanol treatment on the expression of mediators of oxidative stress, inflammation, and extracellular matrix (ECM) degeneration in a mouse aortic dissection (AD) model. Material/Methods Twenty-four 8-month-old C57BL/6J mice were divided into three groups and studied for two weeks: 1) the aortic dissection (AD) Model group (N=8) underwent intraperitoneal injection of angiotensin II (Ang II) (5 ml/kg) three times every 24 h; 2) the mercaptoethanol Treated group (N=8) were given oral mercaptoethanol (2.5 mM); the Normal group (N=8) underwent intraperitoneal injection of noradrenaline (5 mg/kg) three times every 24 h. Sections of mouse aorta were prepared for histology with hematoxylin and eosin (H&E) staining; immunohistochemistry was performed to detect levels of: nuclear factor (erythroid-derived 2)-like 2 (NFE2L2), nuclear factor κB (NF-κB), p65, superoxide dismutase-1 (SOD1), glutamate cysteine ligase catalytic subunit (GCLC), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and matrix metalloproteinase-9 (MMP9). Quantitative reverse transcription-polymerase chain reaction (RT-PCR) evaluated mRNA expression of SOD1, GCLC, TNF-α, IL-1β, and MMP9. Results Mercaptoethanol treatment inhibited Ang II-induced aortic dissection in AD mice, as shown histologically. Mercaptoethanol treatment reduced the expression levels of NFE2L2, NF-κB, p65, TNF-α, IL-1β and increased the expression levels of SOD1, MMP9, and GCLC. Conclusions In an AD mouse model, mercaptoethanol treatment inhibited thoracic and abdominal aortic dissection and reduced aortic tissue expression of mediators of oxidative stress and inflammation and increased the activation of ECM signaling pathways.
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Affiliation(s)
- Lei Zhang
- Department of Cardiothoracic Surgery, Nanjing Clinical Medical College, Second Military Medical University, Nanjing, Jiangsu, China (mainland).,Department of Cardiothoracic Surgery, Jinling Hospital, Nanjing, Jiangsu, China (mainland)
| | - Changtian Wang
- Department of Cardiothoracic Surgery, Jinling Hospital, Nanjing, Jiangsu, China (mainland)
| | - Zhilong Xi
- Department of Cardiothoracic Surgery, Jinling Hospital, Nanjing, Jiangsu, China (mainland)
| | - Demin Li
- Department of Cardiothoracic Surgery, Jinling Hospital, Nanjing, Jiangsu, China (mainland)
| | - Zhiyun Xu
- Department of Thoracic and Cardiac Surgery, Changhai Hospital, Second Military University, Shanghai, China (mainland)
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29
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Xuan Y, Wang Z, Liu R, Haraldsson H, Hope MD, Saloner DA, Guccione JM, Ge L, Tseng E. Wall stress on ascending thoracic aortic aneurysms with bicuspid compared with tricuspid aortic valve. J Thorac Cardiovasc Surg 2018; 156:492-500. [PMID: 29656820 DOI: 10.1016/j.jtcvs.2018.03.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 01/23/2018] [Accepted: 03/05/2018] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Guidelines for repair of bicuspid aortic valve-associated ascending thoracic aortic aneurysms have been changing, most recently to the same criteria as tricuspid aortic valve-ascending thoracic aortic aneurysms. Rupture/dissection occurs when wall stress exceeds wall strength. Recent studies suggest similar strength of bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms; thus, comparative wall stress may better predict dissection in bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms. Our aim was to determine whether bicuspid aortic valve-ascending thoracic aortic aneurysms had higher wall stresses than their tricuspid aortic valve counterparts. METHODS Patients with bicuspid aortic valve- and tricuspid aortic valve-ascending thoracic aortic aneurysms (bicuspid aortic valve = 17, tricuspid aortic valve = 19) greater than 4.5 cm underwent electrocardiogram-gated computed tomography angiography. Patient-specific 3-dimensional geometry was reconstructed and loaded to systemic pressure after accounting for prestress geometry. Finite element analyses were performed using the LS-DYNA solver (LSTC Inc, Livermore, Calif) with user-defined fiber-embedded material model to determine ascending thoracic aortic aneurysm wall stress. RESULTS Bicuspid aortic valve-ascending thoracic aortic aneurysms 99th-percentile longitudinal stresses were 280 kPa versus 242 kPa (P = .028) for tricuspid aortic valve-ascending thoracic aortic aneurysms in systole. These stresses did not correlate to diameter for bicuspid aortic valve-ascending thoracic aortic aneurysms (r = -0.004) but had better correlation to tricuspid aortic valve-ascending thoracic aortic aneurysms diameter (r = 0.677). Longitudinal stresses on sinotubular junction were significantly higher in bicuspid aortic valve-ascending thoracic aortic aneurysms than in tricuspid aortic valve-ascending thoracic aortic aneurysms (405 vs 329 kPa, P = .023). Bicuspid aortic valve-ascending thoracic aortic aneurysm 99th-percentile circumferential stresses were 548 kPa versus 462 kPa (P = .033) for tricuspid aortic valve-ascending thoracic aortic aneurysms, which also did not correlate to bicuspid aortic valve-ascending thoracic aortic aneurysm diameter (r = 0.007). CONCLUSIONS Circumferential and longitudinal stresses were greater in bicuspid aortic valve- than tricuspid aortic valve-ascending thoracic aortic aneurysms and were more pronounced in the sinotubular junction. Peak wall stress did not correlate with bicuspid aortic valve-ascending thoracic aortic aneurysm diameter, suggesting diameter alone in this population may be a poor predictor of dissection risk. Our results highlight the need for patient-specific aneurysm wall stress analysis for accurate dissection risk prediction.
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Affiliation(s)
- Yue Xuan
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Zhongjie Wang
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Raymond Liu
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Henrik Haraldsson
- Department of Radiology, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Michael D Hope
- Department of Radiology, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - David A Saloner
- Department of Radiology, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Julius M Guccione
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Liang Ge
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif
| | - Elaine Tseng
- Department of Surgery, University of California San Francisco and San Francisco Veterans Affairs Medical Centers, San Francisco, Calif.
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Plonek T, Zak M, Burzynska K, Rylski B, Gozdzik A, Kustrzycki W, Beyersdorf F, Jasinski M, Filipiak J. The combined impact of mechanical factors on the wall stress of the human ascending aorta - a finite elements study. BMC Cardiovasc Disord 2017; 17:297. [PMID: 29262774 PMCID: PMC5738844 DOI: 10.1186/s12872-017-0733-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/11/2017] [Indexed: 01/16/2023] Open
Affiliation(s)
- Tomasz Plonek
- Department of Cardiac and Thoracic Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland.
| | - Malgorzata Zak
- Department of Biomedical Engineering, Mechatronics and Theory of Mechanisms, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Karolina Burzynska
- Department of Biomedical Engineering, Mechatronics and Theory of Mechanisms, Wroclaw University of Science and Technology, Wroclaw, Poland
| | - Bartosz Rylski
- Department of Cardio-vascular Surgery, Heart Centre Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Anna Gozdzik
- Department of Cardiac and Thoracic Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland
| | - Wojciech Kustrzycki
- Department of Cardiac and Thoracic Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland
| | - Friedhelm Beyersdorf
- Department of Cardio-vascular Surgery, Heart Centre Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Marek Jasinski
- Department of Cardiac and Thoracic Surgery, Wroclaw Medical University, Borowska 213, 50-556, Wroclaw, Poland
| | - Jaroslaw Filipiak
- Department of Biomedical Engineering, Mechatronics and Theory of Mechanisms, Wroclaw University of Science and Technology, Wroclaw, Poland
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31
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Pasta S, Agnese V, Di Giuseppe M, Gentile G, Raffa GM, Bellavia D, Pilato M. In Vivo Strain Analysis of Dilated Ascending Thoracic Aorta by ECG-Gated CT Angiographic Imaging. Ann Biomed Eng 2017; 45:2911-2920. [DOI: 10.1007/s10439-017-1915-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/31/2017] [Indexed: 01/13/2023]
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32
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Pasta S, Gentile G, Raffa G, Bellavia D, Chiarello G, Liotta R, Luca A, Scardulla C, Pilato M. In Silico Shear and Intramural Stresses are Linked to Aortic Valve Morphology in Dilated Ascending Aorta. Eur J Vasc Endovasc Surg 2017; 54:254-263. [DOI: 10.1016/j.ejvs.2017.05.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 05/25/2017] [Indexed: 10/19/2022]
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33
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Invited Commentary. Ann Thorac Surg 2017. [DOI: 10.1016/j.athoracsur.2016.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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34
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Phillippi JA, Hill JC, Billaud M, Green BR, Kotlarczyk MP, Gleason TG. Bicuspid Aortic Valve Morphotype Correlates With Regional Antioxidant Gene Expression Profiles in the Proximal Ascending Aorta. Ann Thorac Surg 2017; 104:79-87. [PMID: 28185644 DOI: 10.1016/j.athoracsur.2016.10.039] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 08/13/2016] [Accepted: 10/17/2016] [Indexed: 01/16/2023]
Abstract
BACKGROUND Bicuspid aortic valve (BAV) is associated with asymmetric dilatation of the proximal ascending aorta. We previously demonstrated increased susceptibility of smooth muscle cells to oxidative stress in the BAV-aneurysmal aorta and hypothesized that antioxidant expression is regionally defined and influenced by the BAV morphotype. METHODS BAV valve morphology was defined according to number of raphes: type 0 (0 raphes), type 1 (1 raphe), or type 2 (2 raphes) and by the raphe location among the left (L), right (R) or non (N) coronary cusps. Ascending aortic specimens were partitioned into three regions corresponding to the sinuses of Valsalva, denoted R, N (greater curve), and L (lesser curve). Transcripts 1, 2, and 3 from the gene expressing superoxide dismutase (Sod) were quantified in all three regions. Results were compared with aneurysmal and nonaneurysmal aortic specimens from patients with a tricuspid aortic valve. RESULTS Region-specific Sod1 upregulation and Sod2 downregulation were dependent on the BAV morphotype. Sod3 was uniformly downregulated in all regions in a morphotype-independent manner. Sod1 upregulation was noted in the R region of the nonaneurysmal type 1 L/R morphotype. Aortic valve regurgitation, but not stenosis, affected the expression of Sod isoforms in specimens of degenerative aneurysms. CONCLUSIONS Region-specific transcription profiles of Sod on the basis of BAV morphotype deepen our understanding of its associated aortopathy and provide biological insight on the asymmetric dilatation pattern. This work indicates regional differences exist in the oxidative stress biology of the proximal aortic wall, and this may lead to newer diagnostic techniques to adjudicate aortic catastrophe risk.
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Affiliation(s)
- Julie A Phillippi
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Bioengineering, McGowan Institute for Regenerative Medicine, and Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jennifer C Hill
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Marie Billaud
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Benjamin R Green
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Mary P Kotlarczyk
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Thomas G Gleason
- Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania; Department of Bioengineering, McGowan Institute for Regenerative Medicine, and Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, Pennsylvania.
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Singh H, Ali S, Luni FK, Hashmi F, Taleb M. Isolated rupture of bicuspid aortic valve following blunt chest trauma: a case report and systematic review of literature. Cardiovasc Diagn Ther 2017; 7:89-91. [PMID: 28164016 DOI: 10.21037/cdt.2016.05.03] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Blunt trauma to chest cause injury to various cardiac structures. Isolated rupture of aortic valve without aortic dissection is rare complication of blunt chest trauma and can be caused by a tear or avulsion of the valve. We report a case of a 35-year-old male who presented with severe aortic insufficiency due to rupture of a non-infected congenital bicuspid aortic valve following non-penetrating chest trauma. The diagnosis was suggested by echocardiography and was confirmed by intra-operative and histological findings. The patient was successfully treated with surgical valve replacement with uneventful postoperative course and recovery. We describe patho-physiology, clinical manifestations, management and the literature review of traumatic rupture of bicuspid aortic valve.
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Affiliation(s)
- Hemindermeet Singh
- 1 Department of Cardiovascular Fellowship, 2 Department of Cardiothoracic Surgery, Mercy St Vincent Medical Center and Hospital, Toledo, OH, USA
| | - Sajid Ali
- 1 Department of Cardiovascular Fellowship, 2 Department of Cardiothoracic Surgery, Mercy St Vincent Medical Center and Hospital, Toledo, OH, USA
| | - Faraz Khan Luni
- 1 Department of Cardiovascular Fellowship, 2 Department of Cardiothoracic Surgery, Mercy St Vincent Medical Center and Hospital, Toledo, OH, USA
| | - Fayyaz Hashmi
- 1 Department of Cardiovascular Fellowship, 2 Department of Cardiothoracic Surgery, Mercy St Vincent Medical Center and Hospital, Toledo, OH, USA
| | - Mohammed Taleb
- 1 Department of Cardiovascular Fellowship, 2 Department of Cardiothoracic Surgery, Mercy St Vincent Medical Center and Hospital, Toledo, OH, USA
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Singh S, Xu X, Pepper J, Izgi C, Treasure T, Mohiaddin R. Effects of aortic root motion on wall stress in the Marfan aorta before and after personalised aortic root support (PEARS) surgery. J Biomech 2016; 49:2076-2084. [DOI: 10.1016/j.jbiomech.2016.05.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/13/2016] [Accepted: 05/15/2016] [Indexed: 10/21/2022]
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Affiliation(s)
- John S Ikonomidis
- Division of Cardiothoracic Surgery, Medical University of South Carolina, Charleston, SC.
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Wisneski AD, Mookhoek A, Chitsaz S, Hope MD, Guccione JM, Ge L, Tseng EE. Bicuspid Aortic Valve-Associated Ascending Thoracic Aortic Aneurysm: Patient-Specific Finite Element Analysis. THE JOURNAL OF HEART VALVE DISEASE 2015; 24:714-721. [PMID: 27997777 PMCID: PMC8505358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Elective repair of bicuspid aortic valve (BAV)-associated ascending thoracic aortic aneurysm (aTAA) is recommended at lower size limits than tricuspid aortic valve (TAV)-associated aTAA. Rupture/dissection can occur when wall stress exceeds wall strength. Previously, a validated computational method was developed for determining aTAA wall stress, but to date this method has not applied to a patient-specific BAV aTAA. The study aim was to develop a patient-specific BAV aTAA computational model to determine regional wall stress, using the required zero-pressure geometry, wall thickness, material properties, and residual stress. METHODS A BAV aTAA specimen was excised intact during elective repair, and zero-pressure geometry generated using micro-computed tomography. Residual stress was determined from the aTAA opening angle. aTAA material properties determined using biaxial stretch testing were incorporated into an Ogden hyperelastic model. Finite element analyses (FEAs) were performed in LS-DYNA to determine wall stress distribution and magnitudes at systemic pressure. RESULTS The left aTAA region had the highest stiffness, followed by the right, and then anterior/posterior walls, suggesting regional variability in mechanical properties. During systole, the mean principal wall stresses were 108.8 kPa (circumferential) and 59.9 kPa (longitudinal), while peak wall stresses were 789.4 kPa (circumferential) and 618.8 kPa (longitudinal). Elevated wall stress pockets were seen in anatomic left aTAA regions. CONCLUSIONS To the present authors' knowledge, this was the first patient-specific BAV aTAA model based on surgical specimens to be developed. Surgical specimens serve as the 'gold standard' for determining wall stress to validate models based on in-vivo imaging data alone. Regions of maximal wall stress may indicate sites most prone to rupture, and are crucial for evaluating rupture risk based on the wall stress/strength relationship.
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Affiliation(s)
- Andrew D Wisneski
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Aart Mookhoek
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Sam Chitsaz
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Michael D Hope
- Department of Radiology, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Julius M Guccione
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Liang Ge
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Elaine E Tseng
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA, USA
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Martufi G, Forneris A, Appoo JJ, Di Martino ES. Is There a Role for Biomechanical Engineering in Helping to Elucidate the Risk Profile of the Thoracic Aorta? Ann Thorac Surg 2015; 101:390-8. [PMID: 26411753 DOI: 10.1016/j.athoracsur.2015.07.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 06/29/2015] [Accepted: 07/13/2015] [Indexed: 11/29/2022]
Abstract
Clinical estimates of rupture and dissection risk of thoracic aortic aneurysms are based on nonsophisticated measurements of maximum diameter and growth rate. The use of aortic size alone may overlook the role that vessel heterogeneity plays in assessing the risk of catastrophic complications. Biomechanics may help provide a more nuanced approach to predict the behavior of thoracic aortic aneurysms. In this report, we review modeling studies with an emphasis on mechanical and fluid dynamics analyses. We identify open problems and highlight the future possibility of a multidisciplinary approach that includes biomechanics and imaging to evaluate the likelihood of rupture or dissection.
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Affiliation(s)
- Giampaolo Martufi
- Department of Civil Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Arianna Forneris
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, Alberta, Canada
| | - Jehangir J Appoo
- Division of Cardiac Surgery, Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Elena S Di Martino
- Department of Civil Engineering, Centre for Bioengineering Research and Education, and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.
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Krishnan K, Ge L, Haraldsson H, Hope MD, Saloner DA, Guccione JM, Tseng EE. Ascending thoracic aortic aneurysm wall stress analysis using patient-specific finite element modeling of in vivo magnetic resonance imaging. Interact Cardiovasc Thorac Surg 2015; 21:471-80. [PMID: 26180089 DOI: 10.1093/icvts/ivv186] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 04/17/2015] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Rupture/dissection of ascending thoracic aortic aneurysms (aTAAs) carries high mortality and occurs in many patients who did not meet size criteria for elective surgery. Elevated wall stress may better predict adverse events, but cannot be directly measured in vivo, rather determined from finite element (FE) simulations. Current computational models make assumptions that limit accuracy, most commonly using in vivo imaging geometry to represent zero-pressure state. Accurate patient-specific wall stress requires models with zero-pressure three-dimensional geometry, material properties, wall thickness and residual stress. We hypothesized that wall stress calculated from in vivo imaging geometry at systemic pressure underestimates that using zero-pressure geometry. We developed a novel method to derive zero-pressure geometry from in vivo imaging at systemic pressure. The purpose of this study was to develop the first patient-specific aTAA models using magnetic resonance imaging (MRI) to assess material properties and zero-pressure geometry. Wall stress results from FE models using systemic pressure were compared with those from models using zero-pressure correction. METHODS Patients with aTAAs <5 cm underwent ECG-gated computed tomography angiography (CTA) and displacement encoding with stimulated echo (DENSE)-MRI. CTA lumen geometry was used to create surface contour meshes of aTAA geometry. DENSE-MRI measured cyclic aortic wall strain from which wall material property was derived. Zero- and systemic pressure geometries were created. Simulations were loaded to systemic pressure using the ABAQUS FE software. Wall stress analyses were compared between zero-pressure-corrected and systemic pressure geometry FE models. RESULTS Peak first principal wall stress (primarily aligned in the circumferential direction) at systolic pressure for the zero-pressure correction models was 430.62 ± 69.69 kPa, whereas that without zero-pressure correction was 312.55 ± 39.65 kPa (P = 0.004). Peak second principal wall stress (primarily aligned in the longitudinal direction) at systolic pressure for the zero-pressure correction models was 200.77 ± 43.13 kPa, whereas that without zero-stress correction was 156.25 ± 25.55 kPa (P = 0.02). CONCLUSIONS Previous FE aTAA models from in vivo CT and MRI have not accounted for zero-pressure geometry or patient-specific material property. We demonstrated that zero-pressure correction significantly impacts wall stress results. Future computational models that use wall stress to predict aTAA adverse events must take into account zero-pressure geometry and patient material property for accurate wall stress determination.
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Affiliation(s)
- Kapil Krishnan
- Department of Surgery, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Liang Ge
- Department of Surgery, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Henrik Haraldsson
- Department of Radiology, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Michael D Hope
- Department of Radiology, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - David A Saloner
- Department of Radiology, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Julius M Guccione
- Department of Surgery, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
| | - Elaine E Tseng
- Department of Surgery, University of California San Francisco Medical Center and San Francisco VA Medical Center, San Francisco, CA, USA
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Computational Biomechanics in Thoracic Aortic Dissection: Today’s Approaches and Tomorrow’s Opportunities. Ann Biomed Eng 2015; 44:71-83. [DOI: 10.1007/s10439-015-1366-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 06/11/2015] [Indexed: 01/16/2023]
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Adamo L, Braverman AC. Surgical threshold for bicuspid aortic valve aneurysm: a case for individual decision-making. Heart 2015; 101:1361-7. [DOI: 10.1136/heartjnl-2014-306601] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/14/2015] [Indexed: 01/06/2023] Open
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Singh SD, Xu XY, Pepper JR, Treasure T, Mohiaddin RH. Biomechanical properties of the Marfan's aortic root and ascending aorta before and after personalised external aortic root support surgery. Med Eng Phys 2015; 37:759-66. [PMID: 26054807 DOI: 10.1016/j.medengphy.2015.05.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 02/16/2015] [Accepted: 05/09/2015] [Indexed: 10/23/2022]
Abstract
Marfan syndrome is an inherited systemic connective tissue disease which may lead to aortic root disease causing dilatation, dissection and rupture of the aorta. The standard treatment is a major operation involving either an artificial valve and aorta or a complex valve repair. More recently, a personalised external aortic root support (PEARS) has been used to strengthen the aorta at an earlier stage of the disease avoiding risk of both rupture and major surgery. The aim of this study was to compare the stress and strain fields of the Marfan aortic root and ascending aorta before and after insertion of PEARS in order to understand its biomechanical implications. Finite element (FE) models were developed using patient-specific aortic geometries reconstructed from pre and post-PEARS magnetic resonance images in three Marfan patients. For the post-PEARS model, two scenarios were investigated-a bilayer model where PEARS and the aortic wall were treated as separate layers, and a single-layer model where PEARS was incorporated into the aortic wall. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Results from our FE models with patient-specific geometries show that peak aortic stresses and displacements before PEARS were located at the sinuses of Valsalva but following PEARS surgery, these peak values were shifted to the aortic arch, particularly at the interface between the supported and unsupported aorta. Further studies are required to assess the statistical significance of these findings and how PEARS compares with the standard treatment.
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Affiliation(s)
- S D Singh
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - X Y Xu
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
| | - J R Pepper
- Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK; National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK
| | - T Treasure
- Clinical Operational Research, Department of Mathematics, University College London, 4 Taviton Street, London WC1H 0BT, UK
| | - R H Mohiaddin
- Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK; National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK
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Martin C, Sun W, Elefteriades J. Patient-specific finite element analysis of ascending aorta aneurysms. Am J Physiol Heart Circ Physiol 2015; 308:H1306-16. [PMID: 25770248 DOI: 10.1152/ajpheart.00908.2014] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 03/03/2015] [Indexed: 12/30/2022]
Abstract
Catastrophic ascending aorta aneurysm (AsAA) dissection and rupture can be prevented by elective surgical repair, but identifying individuals at risk remains a challenge. Typically the decision to operate is based primarily on the overall aneurysm size, which may not be a reliable indicator of risk. In this study, AsAA inflation and rupture was simulated in 27 patient-specific finite element models constructed from clinical CT imaging data and tissue mechanical testing data from matching patients. These patients included n = 8 with concomitant bicuspid aortic valve (BAV), n = 10 with bovine aortic arch (BAA), and n = 10 with neither BAV nor BAA. AsAA rupture risk was found to increase with elevated systolic wall stress and tissue stiffness. The aortic size index was sufficient for identifying the patients with the lowest risk of rupture, but unsuitable for delineating between patients at moderate and high risk. There was no correlation between BAV or BAA and AsAA rupture risk; however, the AsAA morphology was different among these patients. These results support the use of mechanical parameters such as vessel wall stress and tissue stiffness for AsAA presurgical evaluation.
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Affiliation(s)
- Caitlin Martin
- Tissue Mechanics Laboratory, The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia; and
| | - Wei Sun
- Tissue Mechanics Laboratory, The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia; and
| | - John Elefteriades
- Aortic Institute of Yale-New Haven Hospital, Yale University, New Haven, Connecticut
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Cao K, Sucosky P. Effect of Bicuspid Aortic Valve Cusp Fusion on Aorta Wall Shear Stress: Preliminary Computational Assessment and Implication for Aortic Dilation. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/wjcd.2015.56016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Atkins SK, Sucosky P. Etiology of bicuspid aortic valve disease: Focus on hemodynamics. World J Cardiol 2014; 6:1227-1233. [PMID: 25548612 PMCID: PMC4278157 DOI: 10.4330/wjc.v6.i12.1227] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2014] [Revised: 10/08/2014] [Accepted: 12/01/2014] [Indexed: 02/06/2023] Open
Abstract
The bicuspid aortic valve (BAV) is the most common form of inheritable cardiac defect. Although this abnormality may still achieve normal valvular function, it is often associated with secondary valvular and aortic complications such as calcific aortic valve disease and aortic dilation. The clinical significance and economic burden of BAV disease justify the need for improved clinical guidelines and more robust therapeutic modalities, which address the root-cause of those pathologies. Unfortunately, the etiology of BAV valvulopathy and aortopathy is still a debated issue. While the BAV anatomy and its secondary complications have been linked historically to a common genetic root, recent advances in medical imaging have demonstrated the existence of altered hemodynamics near BAV leaflets prone to calcification and BAV aortic regions vulnerable to dilation. The abnormal mechanical stresses imposed by the BAV on its leaflets and on the aortic wall could be transduced into cell-mediated processes, leading ultimately to valvular calcification and aortic medial degeneration. Despite increasing evidence for this hemodynamic etiology, the demonstration of the involvement of mechanical abnormalities in the pathogenesis of BAV disease requires the investigation of causality between the blood flow environment imposed on the leaflets and the aortic wall and the local biology, which has been lacking to date. This editorial discusses the different hypothetical etiologies of BAV disease with a particular focus on the most recent advances in cardiovascular imaging, flow characterization techniques and tissue culture methodologies that have provided new evidence in support of the hemodynamic theory.
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Mirabella L, Barker AJ, Saikrishnan N, Coco ER, Mangiameli DJ, Markl M, Yoganathan AP. MRI-based Protocol to Characterize the Relationship Between Bicuspid Aortic Valve Morphology and Hemodynamics. Ann Biomed Eng 2014; 43:1815-27. [PMID: 25533768 DOI: 10.1007/s10439-014-1214-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 12/04/2014] [Indexed: 11/28/2022]
Abstract
Bicuspid aortic valve (BAV) is the most common congenital heart defect and can lead to severe complications. Many studies have been conducted to evaluate the potential of geometric and hemodynamic biomarkers to predict BAV-related aortopathy. This work proposes a novel semi-automatic protocol to characterize geometry and hemodynamics of aorta and aortic valve based on 2D cine and 4D flow MRI data. The protocol was applied to 12 BAV and 12 control subjects. Statistical differences between the groups were identified and linear regression models were investigated to elucidate the potential of this protocol to investigate the risk of disease progression. Statistical differences between the groups were found for orifice eccentricity, aorta diameter, velocity, jet angle and flow displacement. Key findings of the regression analysis include the association in the proximal ascending aorta between aorta diameter and mean velocity (negative), jet angle (positive) and flow displacement (positive), in the combined cohort. Positive association between flow displacement in the proximal aorta and orifice jet angle in TAV subjects was found. This study represents a pilot application of a protocol for standardized assessment of aortic geometry and hemodynamics associated with BAV disease. Its limited need for user input is advantageous for large cohort studies.
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Affiliation(s)
- Lucia Mirabella
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Technology Enterprise Park, Suite 200, 387 Technology Circle, Atlanta, GA, 30313-2412, USA
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Fused aortic valve without an elliptical-shaped systolic orifice in patients with severe aortic stenosis: cardiac computed tomography is useful for differentiation between bicuspid aortic valve with raphe and tricuspid aortic valve with commissural fusion. Eur Radiol 2014; 25:1208-17. [PMID: 25424562 DOI: 10.1007/s00330-014-3494-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 10/29/2014] [Accepted: 11/10/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVE The objective is to determine cardiac computed tomography (CCT) features capable of differentiating between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) in severe aortic stenosis (AS) patients with fused cusp and without elliptical-shaped systolic orifices. METHODS We retrospectively enrolled 53 patients who had severe AS with fused cusps and without an elliptical-shaped systolic orifice on CCT and who had undergone surgery. CCT features were analyzed using: 1) aortic valve findings including cusp size, cusp area, opening shape, midline calcification, fusion length, calcium volume score, and calcium grade; 2) diameters of ascending and descending aorta, and main pulmonary artery; and 3) rheumatic mitral valve findings. The variables were evaluated using univariate and multivariate logistic regression analyses. RESULTS At surgery, 19 patients had BAV and 34 had TAV. CCT features including uneven cusp size, uneven cusp area, round-shaped systolic orifice, longer cusp fusion, and dilatation of ascending aorta were significantly associated with BAV (P < 0.05). In particular, fusion length (OR, 1.76; P = 0.001), uneven cusp area (OR, 10.46; P = 0.012), and midline calcification (OR, 0.08; P = 0.013) were strongly associated with BAV. CONCLUSION CCT provides diagnostic clues that helps differentiate between BAV with raphe and TAV with commissural fusion in patients with severe AS. KEY POINTS • Accurate morphologic assessment of the aortic valve is important for treatment planning. • It is difficult to differentiate BAV from TAV with a fused cusp. • CCT provides diagnostic clues for the differentiation of BAV and TAV.
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Phomakay V, Huett WG, Gossett JM, Tang X, Bornemeier RA, Collins RT. β-Blockers and angiotensin converting enzyme inhibitors: comparison of effects on aortic growth in pediatric patients with Marfan syndrome. J Pediatr 2014; 165:951-5. [PMID: 25109242 PMCID: PMC4330566 DOI: 10.1016/j.jpeds.2014.07.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 05/27/2014] [Accepted: 07/02/2014] [Indexed: 10/27/2022]
Abstract
OBJECTIVES Angiotensin converting enzyme inhibitors (ACEI) have been shown to decrease aortic growth velocity (AGV) in Marfan syndrome (MFS). We sought to compare the effect of β-blockers and ACEI on AGV in MFS. STUDY DESIGN We retrospectively reviewed all data from all patients with MFS seen at Arkansas Children's Hospital between January 1, 1976 and January 1, 2013. Generalized least squares were used to evaluate AGV over time as a function of age, medication group, and the interaction between the 2. A mixed model was used to compare AGV between medication groups as a function of age, medication group (none, β-blocker, ACEI), and the interaction between the 2. RESULTS A total of 67 patients with confirmed MFS were identified (34/67, 51% female). Mean age at first encounter was 13 ± 10 years, with mean follow-up of 7.6 ± 5.8 years. There were 839 patient encounters with a median of 10 (range 2-42) encounters per patient. AGV was nearly normal in the β-blocker group, and was less than either the ACEI or untreated groups. The AGV was higher than normal in ACEI and untreated groups (P < .001 for both). CONCLUSIONS β-blocker therapy results in near-normalization of AGV in MFS. ACEI did not decrease AGV in a clinically significant manner.
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Affiliation(s)
- Venusa Phomakay
- Arkansas Children's Hospital, Little Rock, AR; The University of Arkansas for Medical Sciences, Little Rock, AR
| | | | - Jeffrey M Gossett
- Arkansas Children's Hospital, Little Rock, AR; The University of Arkansas for Medical Sciences, Little Rock, AR
| | - Xinyu Tang
- Arkansas Children's Hospital, Little Rock, AR; The University of Arkansas for Medical Sciences, Little Rock, AR
| | - Renee A Bornemeier
- Arkansas Children's Hospital, Little Rock, AR; The University of Arkansas for Medical Sciences, Little Rock, AR
| | - R Thomas Collins
- Arkansas Children's Hospital, Little Rock, AR; The University of Arkansas for Medical Sciences, Little Rock, AR.
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Wisneski AD, Mookhoek A, Chitsaz S, Hope MD, Guccione JM, Ge L, Tseng EE. Patient-specific finite element analysis of ascending thoracic aortic aneurysm. THE JOURNAL OF HEART VALVE DISEASE 2014; 23:765-772. [PMID: 25790625 PMCID: PMC5127264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY Rupture/dissection of ascending thoracic aortic aneurysm (aTAA) is a cardiovascular emergency. Elective surgical repair is primarily based on maximum diameter, but complications have occurred under the size limits for surgical intervention. aTAA wall stress may be a better predictor of patient-specific rupture risk, but cannot be directly measured in vivo. The study aim was to develop an aTAA computational model associated with tricuspid aortic valve (TAV) to determine patient-specific wall stresses. METHODS A TAV-associated aTAA was excised intact during surgery. Zero-pressure geometry was generated from microcomputed tomography, and an opening angle was used to calculate residual stress. Material properties determined from stress-strain data were incorporated into an Ogden hyperelastic model. Wall stress distribution and magnitudes at systemic pressure were determined using finite element analyses (FEA) in LS-DYNA. RESULTS Regional material property differences were noted: the left aTAA region had a higher stiffness compared to the right, and anterior/posterior walls. During systole, the mean principal wall stresses were 172.0 kPa (circumferential) and 71.9 kPa (longitudinal), while peak wall stresses were 545.1 kPa (circumferential) and 430.1 kPa (longitudinal). Elevated wall stress pockets were seen in anatomic left and right aTAA regions. CONCLUSION A validated computational approach was demonstrated to determine aTAA wall stresses in a patient-specific fashion, taking into account the required zero-stress geometry, wall thickness, material properties and residual stress. Regions of maximal wall stress may indicate the sites most prone to rupture. The creation of a patient-specific aTAA model based on a surgical specimen is necessary to serve as the 'gold standard' for comparing models based on in-vivo data alone. Validated data using the surgical specimen are essential for establishing wall stress and rupture-risk relationships.
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Affiliation(s)
- Andrew D. Wisneski
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
| | - Aart Mookhoek
- Department of Cardiothoracic Surgery, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Sam Chitsaz
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
| | - Michael D. Hope
- Department of Radiology, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
| | - Julius M. Guccione
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
| | - Liang Ge
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
| | - Elaine E. Tseng
- Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, CA
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