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Li L, Wang Y, Jin P, Yang T, Zhu G, Li Y, Tang J, Liu Y, Yang J. Hemodynamics in the treatment of pseudoaneurysm caused by extreme constriction of aortic arch with coated stent. Front Cardiovasc Med 2024; 11:1363230. [PMID: 39228660 PMCID: PMC11368758 DOI: 10.3389/fcvm.2024.1363230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Accepted: 06/24/2024] [Indexed: 09/05/2024] Open
Abstract
Objectives To evaluate the changes in distal vascular morphology and hemodynamics in patients with extremely severe aortic coarctation (CoA) after covered palliative (CP) stent dilation with different surgical strategies. Materials and methods Perioperative computed tomography angiography and digital subtraction angiography were utilized to construct three aortic models with varying stenosis rates and one follow-up model in a patient with extremely severe CoA. The models included: an idealized non-stenosed model (A: 0%), a model post initial stent deployment (B: 28%), a model post balloon expansion (C: 39%), and a model 18 months after post-balloon expansion (D: 39%). Consistent boundary conditions were applied to all models, and hemodynamic simulation was conducted using the pure fluid method. Results The narrowest and distal diameter of the stent increased by 34.71% and 59.29%, respectively, from model B to C. Additionally, the distal diameter of the stent increased by -13.80% and +43.68% compared to the descending aorta diameter, respectively. Furthermore, the ellipticity of the maximum cross-section of the aneurysm region in model A to D continued to increase. The oscillatory shear index at the stenosis to the region of the aneurysm were found to be higher in Models A and B, and lower in Models C and D. At the moment of maximum flow velocity, the blood flow distribution in models A and B was more uniform in the widest section of the blood vessels at the distal end of the stenosis, whereas models C and D exhibited disturbed blood flow with more than 2 eddy currents. The time-averaged wall shear stress (TAWSS) decreased in the distal and basal aneurysms, while it significantly increased at the step position. The aneurysmal region exhibited an endothelial cell activation potential value lower than 0.4 Pa-1. Conclusion In patients with extremely severe CoA, it is crucial to ensure that the expanded diameter at both ends of the CP stent does not exceed the native vascular diameter during deployment. Our simulation results demonstrate that overdilation leads to a decrease in the TAWSS above the injured vessel, creating an abnormal hemodynamic environment that may contribute to the development and enlargement of false aneurysms in the early postoperative period. Clinical Trial Registration ClinicalTrials.gov, (NCT02917980).
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Affiliation(s)
- Lanlan Li
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Yiwei Wang
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Ping Jin
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Tingting Yang
- School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Guangyu Zhu
- School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Yuxi Li
- Department of Ultrasound Medicine, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Jiayou Tang
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Yang Liu
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
| | - Jian Yang
- Department of Cardiovascular Surgery, Xijing Hospital, Air Force Medical University, Xi’an, Shaanxi, China
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2
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Zhang Z, Xu X, Li T, Xin YF, Tong J. Region-specific delamination strength of ascending thoracic aortic aneurysm of elderly hypertensive patients with bicuspid and tricuspid aortic valves. Med Eng Phys 2024; 126:104157. [PMID: 38621853 DOI: 10.1016/j.medengphy.2024.104157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/18/2024] [Accepted: 03/16/2024] [Indexed: 04/17/2024]
Abstract
Both ageing and hypertension are clinical factors that may lead to a higher propensity for dissection or rupture of ascending thoracic aortic aneurysms (ATAAs). This study sought to investigate effect of valve morphology on regional delamination strength of ATAAs in the elderly hypertensive patients. Whole fresh ATAA samples were harvested from 23 hypertensive patients (age, 71 ± 8 years) who underwent elective aortic surgery. Peeling tests were performed to measure region-specific delamination strengths of the ATAAs, which were compared between patients with bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV). The regional delamination strengths of the ATAAs were further correlated with patient ages and aortic diameters for BAV and TAV groups. In the anterior and right lateral regions, the longitudinal delamination strengths of the ATAAs were statistically significantly higher for BAV patients than TAV patients (33 ± 7 vs. 23 ± 8 mN/mm, p = 0.01; 30 ± 7 vs. 19 ± 9 mN/mm, p = 0.02). For both BAV and TAV patients, the left lateral region exhibited significantly higher delamination strengths in both directions than the right lateral region. Histology revealed that disruption of elastic fibers in the right lateral region of the ATAAs was more severe for the TAV patients than the BAV patients. A strong inverse correlation between longitudinal delamination strength and age was identified in the right lateral region of the ATAAs of the TAV patients. Results suggest that TAV-ATAAs are more vulnerable to aortic dissection than BAV-ATAAs for the elderly hypertensive patients. Regardless of valve morphotypes, the right lateral region may be a special quadrant which is more likely to initiate dissection when compared with other regions.
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Affiliation(s)
- Zhi Zhang
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xiaojuan Xu
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China; Department of Pathology and Pathophysiology, Tongji University School of Medicine, Shanghai, China
| | - Tieyan Li
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yuan-Feng Xin
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.
| | - Jianhua Tong
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China.
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3
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Yuan X, Kan X, Li J, Yan Y, Mirsadraee S, Mittal T, Shah A, Saunders D, Xu XY, Nienaber CA. Four-dimensional analysis of aortic root motion in normal population using retrospective multiphase computed tomography. EUROPEAN HEART JOURNAL. IMAGING METHODS AND PRACTICE 2024; 2:qyae007. [PMID: 39045205 PMCID: PMC11195731 DOI: 10.1093/ehjimp/qyae007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 01/30/2024] [Indexed: 07/25/2024]
Abstract
Aims Aortic root motion is suspected to contribute to proximal aortic dissection. While motion of the aorta in four dimensions can be traced with real-time imaging, displacement and rotation in quantitative terms remain unknown. The hypothesis was to show feasibility of quantification of three-dimensional aortic root motion from dynamic CT imaging. Methods and results Dynamic CT images of 40 patients for coronary assessment were acquired using a dynamic protocol. Scans were ECG-triggered and segmented in 10 time-stepped phases (0-90%) per cardiac cycle. With identification of the sinotubular junction (STJ), a patient-specific co-ordinate system was created with the z-axis (out-of-plane) parallel to longitudinal direction. The left and right coronary ostia were traced at each time-step to quantify downward motion in reference to the STJ plane, motion within the STJ plane (in-plane), and the degree of rotation. Enrolled individuals had an age of 65 ± 12, and 14 were male (35%). The out-of-plane motion was recorded with the largest displacement of 10.26 ± 2.20 and 8.67 ± 1.69 mm referenced by left and right coronary ostia, respectively. The mean downward movement of aortic root was 9.13 ± 1.86 mm. The largest in-plane motion was recorded at 9.17 ± 2.33 mm and 6.51 ± 1.75 mm referenced by left and right coronary ostia, respectively. The largest STJ in-plane motion was 7.37 ± 1.96 mm, and rotation of the aortic root was 11.8 ± 4.60°. Conclusion In vivo spatial and temporal displacement of the aortic root can be identified and quantified from multiphase ECG-gated contrast-enhanced CT images. Knowledge of normal 4D motion of the aortic root may help understand its biomechanical impact in patients with aortopathy and pre- and post-surgical or transcatheter aortic valve replacement.
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Affiliation(s)
- Xun Yuan
- Cardiology and Aortic Centre, Royal Brompton & Harefield Hospitals, Guy’s and St Thomas’ NHS Foundation Trust, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, School of Medicine, Imperial College London, Exhibition Road, London SW7 2BX, UK
| | - Xiaoxin Kan
- Center for Vascular Surgery and Wound Care, Jinshan Hospital, Fudan University, Shanghai, China
- Department of Chemical Engineering, Imperial College London, London, UK
| | - Jianpeng Li
- Department of Cardiovascular Surgery, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Yang Yan
- Department of Cardiovascular Surgery, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Saeed Mirsadraee
- National Heart and Lung Institute, School of Medicine, Imperial College London, Exhibition Road, London SW7 2BX, UK
- Department of Radiology, Royal Brompton & Harefield Hospitals, Guy’s and St Thomas’ NHS Foundation Trust, London, UK
| | - Tarun Mittal
- National Heart and Lung Institute, School of Medicine, Imperial College London, Exhibition Road, London SW7 2BX, UK
- Department of Radiology, Royal Brompton & Harefield Hospitals, Guy’s and St Thomas’ NHS Foundation Trust, London, UK
| | - Andrew Shah
- Department of Radiology, East and North Hertfordshire NHS Foundation Trust, Middlesex, UK
| | - Debbie Saunders
- Department of Radiology, East and North Hertfordshire NHS Foundation Trust, Middlesex, UK
| | - Xiao Yun Xu
- Department of Chemical Engineering, Imperial College London, London, UK
| | - Christoph A Nienaber
- Cardiology and Aortic Centre, Royal Brompton & Harefield Hospitals, Guy’s and St Thomas’ NHS Foundation Trust, Sydney Street, London SW3 6NP, UK
- National Heart and Lung Institute, School of Medicine, Imperial College London, Exhibition Road, London SW7 2BX, UK
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4
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Totaro P, Morganti S, Auricchio F, Pelenghi S. Aortic wall thickness in dilated ascending aorta: Comparison between tricuspid and bicuspid aortic valve. Arch Cardiovasc Dis 2023; 116:498-505. [PMID: 37770332 DOI: 10.1016/j.acvd.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 09/30/2023]
Abstract
BACKGROUND Bicuspid aortic valve (BAV) is frequently associated with dilatation of the thoracic aorta. Peculiar anatomical, histological and mechanical changes of the aortic wall in BAV aortopathy have been hypothesized to suggest an increased risk of acute aortic complications in patients with BAV. AIM In this study we tried to clarify any differences in the adaptability of the aortic wall to the mechanism of dilatation between patients with BAV and those with TAV. METHODS In total, 354 samples were taken from 71 patients undergoing elective aortic surgery and divided into two groups: BAV group (n=16; 101 samples); and TAV group (n=55; 253 samples). Aortic wall thickness was measured with a dedicated caliper. The relationship between aortic wall thickness and aortic dilatation and demographic variables was evaluated cumulatively and comparatively (BAV versus TAV). In patients with more than three samples available, intrapatient variability was also studied. Finally, potential risk factors for severely reduced aortic wall thickness were also assessed. RESULTS Analysis of preoperative characteristics revealed significant differences in patient age (54±16years for BAV and 66±11years for TAV; P=0.0011), with no differences in variables related to aortic dilatation (including phenotype). Cumulative aortic wall thickness was significantly thinner in the anterior than in the posterior wall. In the comparative analysis, aortic wall thickness was significantly thinner in patients with BAV in both the anterior and posterior regions. Furthermore, in patients with BAV, dilatation>51mm was a significant predictor of severely reduced aortic wall thickness. CONCLUSIONS In our experience, patients with BAV aortopathy reached the cut-off for the surgical indication at an early age. Careful monitoring in patients with BAV is mandatory when aortic dilatation has reached 51mm, as it is related to significant anatomical changes.
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MESH Headings
- Humans
- Middle Aged
- Male
- Bicuspid Aortic Valve Disease/diagnostic imaging
- Bicuspid Aortic Valve Disease/surgery
- Bicuspid Aortic Valve Disease/physiopathology
- Female
- Aortic Valve/abnormalities
- Aortic Valve/diagnostic imaging
- Aortic Valve/surgery
- Aortic Valve/pathology
- Aortic Valve/physiopathology
- Aged
- Adult
- Risk Factors
- Dilatation, Pathologic
- Heart Valve Diseases/diagnostic imaging
- Heart Valve Diseases/surgery
- Heart Valve Diseases/physiopathology
- Heart Valve Diseases/pathology
- Heart Valve Diseases/complications
- Tricuspid Valve/diagnostic imaging
- Tricuspid Valve/physiopathology
- Tricuspid Valve/abnormalities
- Tricuspid Valve/pathology
- Tricuspid Valve/surgery
- Retrospective Studies
- Aortic Aneurysm, Thoracic/diagnostic imaging
- Aortic Aneurysm, Thoracic/pathology
- Aortic Aneurysm, Thoracic/physiopathology
- Aortic Aneurysm, Thoracic/surgery
- Aorta, Thoracic/diagnostic imaging
- Aorta, Thoracic/pathology
- Aorta, Thoracic/surgery
- Aorta, Thoracic/physiopathology
- Aorta, Thoracic/abnormalities
- Aortic Valve Disease/diagnostic imaging
- Aortic Valve Disease/surgery
- Aortic Valve Disease/physiopathology
- Aortic Valve Disease/pathology
- Aortic Aneurysm/diagnostic imaging
- Aortic Aneurysm/pathology
- Aortic Aneurysm/surgery
- Aortic Aneurysm/etiology
- Aortic Aneurysm/physiopathology
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Affiliation(s)
- Pasquale Totaro
- Division of Cardiac Surgery, IRCCS Foundation Hospital "San Matteo", Piazzale Golgi 1, 27100 Pavia, Italy.
| | - Simone Morganti
- Department of Electrical, Computer and Biomedical Engineering, University of Pavia, 27100 Pavia, Italy
| | - Ferdinando Auricchio
- Department of Civil Engineering and Architecture, University of Pavia, 27100 Pavia, Italy
| | - Stefano Pelenghi
- Division of Cardiac Surgery, IRCCS Foundation Hospital "San Matteo", Piazzale Golgi 1, 27100 Pavia, Italy
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5
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Wang X, Carpenter HJ, Ghayesh MH, Kotousov A, Zander AC, Amabili M, Psaltis PJ. A review on the biomechanical behaviour of the aorta. J Mech Behav Biomed Mater 2023; 144:105922. [PMID: 37320894 DOI: 10.1016/j.jmbbm.2023.105922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/14/2023] [Accepted: 05/20/2023] [Indexed: 06/17/2023]
Abstract
Large aortic aneurysm and acute and chronic aortic dissection are pathologies of the aorta requiring surgery. Recent advances in medical intervention have improved patient outcomes; however, a clear understanding of the mechanisms leading to aortic failure and, hence, a better understanding of failure risk, is still missing. Biomechanical analysis of the aorta could provide insights into the development and progression of aortic abnormalities, giving clinicians a powerful tool in risk stratification. The complexity of the aortic system presents significant challenges for a biomechanical study and requires various approaches to analyse the aorta. To address this, here we present a holistic review of the biomechanical studies of the aorta by categorising articles into four broad approaches, namely theoretical, in vivo, experimental and combined investigations. Experimental studies that focus on identifying mechanical properties of the aortic tissue are also included. By reviewing the literature and discussing drawbacks, limitations and future challenges in each area, we hope to present a more complete picture of the state-of-the-art of aortic biomechanics to stimulate research on critical topics. Combining experimental modalities and computational approaches could lead to more comprehensive results in risk prediction for the aortic system.
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Affiliation(s)
- Xiaochen Wang
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Harry J Carpenter
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mergen H Ghayesh
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia.
| | - Andrei Kotousov
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Anthony C Zander
- School of Electrical and Mechanical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Marco Amabili
- Department of Mechanical Engineering, McGill University, Montreal H3A 0C3, Canada
| | - Peter J Psaltis
- Adelaide Medical School, The University of Adelaide, Adelaide, South Australia 5005, Australia; Department of Cardiology, Central Adelaide Local Health Network, Adelaide, South Australia 5000, Australia; Vascular Research Centre, Heart Health Theme, South Australian Health & Medical Research Institute (SAHMRI), Adelaide, South Australia 5000, Australia
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6
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Tong J, Xin YF, Zhang Z, Xu X, Li T. Effect of hypertension on the delamination and tensile strength of ascending thoracic aortic aneurysm with a focus on right lateral region. J Biomech 2023; 154:111615. [PMID: 37178496 DOI: 10.1016/j.jbiomech.2023.111615] [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: 02/20/2023] [Revised: 04/18/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023]
Abstract
Hypertension is a major predisposing factor to initiate thoracic aortopathy. The objective of this study is to investigate effect of hypertension on delamination and tensile strength of ascending thoracic aortic aneurysms (ATAAs). A total of 35 fresh ATAA samples were harvested from 19 hypertensive and 16 non-hypertensive patients during elective aortic surgery. Peeling tests with two extension rates were performed to determine delamination strength, while uniaxial tensile (UT) tests were employed to measure failure stresses. The delamination strength and failure stresses of the ATAAs were further correlated with patient ages for hypertensive and non-hypertensive groups. The delamination strength to peel apart the ATAA tissue along the longitudinal direction was statistically significantly lower for the hypertensive patients than that of the non-hypertensive patients (35 ± 11 vs. 49 ± 9 mN/mm, p = 0.02). A higher delamination strength was measured if peeling was performed with a higher extension rate. The circumferential failure stresses were significantly lower for the hypertensive ATAAs than those of the non-hypertensive ATAAs (1.03 ± 0.27 vs. 1.43 ± 0.38 MPa, p = 0.02). Histology showed that laminar structures of elastic fibers were mainly disrupted in the hypertensive ATAAs. The longitudinal delamination strength of the ATAAs was significantly decreased and strongly correlated with ages for the hypertensive patients. Strong inverse correlations were also identified between the circumferential and longitudinal failure stresses of the ATAAs and ages for the hypertensive patients. Results suggest that the ATAAs of the elderly hypertensive patients may have a higher propensity for dissection or rupture. The dissection properties of the ATAA tissue are rate dependent.
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Affiliation(s)
- Jianhua Tong
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, PR China.
| | - Yuan-Feng Xin
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Zhi Zhang
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Xiaojuan Xu
- Institute for Biomedical Engineering and Nano Science, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, PR China; Department of Pathology and Pathophysiology, Tongji University School of Medicine, Shanghai, PR China
| | - Tieyan Li
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, PR China
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7
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Tong TT, Nightingale M, Scott MB, Sigaeva T, Fedak PWM, Barker AJ, Di Martino ES. A classification approach to improve out of sample predictability of structure-based constitutive models for ascending thoracic aortic tissue. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023:e3708. [PMID: 37079441 DOI: 10.1002/cnm.3708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/24/2023] [Accepted: 04/02/2023] [Indexed: 05/03/2023]
Abstract
In this research, a pipeline was developed to assess the out-of-sample predictive capability of structure-based constitutive models of ascending aortic aneurysmal tissue. The hypothesis being tested is that a biomarker can help establish similarities among tissues sharing the same level of a quantifiable property, thus enabling the development of biomarker-specific constitutive models. Biomarker-specific averaged material models were constructed from biaxial mechanical tests of specimens that shared similar biomarker properties such as level of blood-wall shear stress or microfiber (elastin or collagen) degradation in the extracellular matrix. Using a cross-validation strategy commonly used in classification algorithms, biomarker-specific averaged material models were assessed in contrast to individual tissue mechanics of out of sample specimens that fell under the same category but did not contribute to the averaged model's generation. The normalized root means square errors (NRMSE) calculated on out-of-sample data were compared with average models when no categorization was performed versus biomarker-specific models and among different level of a biomarker. Different biomarker levels exhibited statistically different NRMSE when compared among each other, indicating more common features shared by the specimens belonging to the lower error groups. However, no specific biomarkers reached a significant difference when compared to the average model created when No Categorization was performed, possibly on account of unbalanced number of specimens. The method developed could allow for the screening of different biomarkers or combinations/interactions in a systematic manner leading the way to larger datasets and to more individualized constitutive approaches.
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Affiliation(s)
- Tuan-Thinh Tong
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Canada
| | - Miriam Nightingale
- Department of Biomedical Engineering, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Michael B Scott
- Department of Radiology, Northwestern University, Evanston, Illinois, USA
| | - Taisiya Sigaeva
- Department of Systems Design Engineering, University of Waterloo, Waterloo, Canada
| | - Paul W M Fedak
- Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
- Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Alex J Barker
- Department of Radiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Elena S Di Martino
- Department of Biomedical Engineering, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
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8
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Sabernaeemi A, Barzegar Gerdroodbary M, Salavatidezfouli S, Valipour P. Influence of stent-induced vessel deformation on hemodynamic feature of bloodstream inside ICA aneurysms. Biomech Model Mechanobiol 2023:10.1007/s10237-023-01710-9. [PMID: 36947349 PMCID: PMC10366311 DOI: 10.1007/s10237-023-01710-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 03/01/2023] [Indexed: 03/23/2023]
Abstract
One of the effective treatment options for intracranial aneurysms is stent-assisted coiling. Though, previous works have demonstrated that stent usage would result in the deformation of the local vasculature. The effect of simple stent on the blood hemodynamics is still uncertain. In this work, hemodynamic features of the blood stream on four different ICA aneurysm with/without interventional are investigated. To estimate the relative impacts of vessel deformation, four distinctive ICA aneurysm is simulated by the one-way FSI technique. Four hemodynamic factors of aneurysm blood velocity, wall pressure and WSS are compared in the peak systolic stage to disclose the impact of defamation by the stent in two conditions. The stent usage would decrease almost all of the mentioned parameters, except for OSI. Stenting reduces neck inflow rate, while the effect of interventional was not consistent among the aneurysms. The deformation of an aneurysm has a strong influence on the hemodynamics of an aneurysm. This outcome is ignored by most of the preceding investigations, which focused on the pre-interventional state for studying the relationship between hemodynamics and stents. Present results show that the application of stent without coiling would improve most hemodynamic factors, especially when the deformation of the aneurysm is high enough.
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Affiliation(s)
- Amir Sabernaeemi
- Department of Space, Earth and Environment, Chalmers University of Technology, Gothenburg, Sweden.
| | - M Barzegar Gerdroodbary
- Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Sajad Salavatidezfouli
- Mathematics Area, MathLab, International School for Advanced Studies (SISSA), Trieste, Italy
| | - Peiman Valipour
- Department of Textile Engineering, Clothing and Fashion, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran.
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9
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Rostamian A, Fallah K, Rostamiyan Y, Alinejad J. Computational study of the blood hemodynamic inside the cerebral double dome aneurysm filling with endovascular coiling. Sci Rep 2023; 13:2909. [PMID: 36806159 PMCID: PMC9939414 DOI: 10.1038/s41598-023-29988-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 02/14/2023] [Indexed: 02/21/2023] Open
Abstract
The rupture of the aneurysm wall is highly associated with the hemodynamic feature of bloodstream as well as the geometrical feature of the aneurysm. Coiling is known as the most conventional technique for the treatment of intracranial cerebral aneurysms (ICA) in which blood stream is obstructed from entering the sac of the aneurysm. In this study, comprehensive efforts are done to disclose the impacts of the coiling technique on the aneurysm progress and risk of rupture. The computational fluid dynamic method is used for the analysis of the blood hemodynamics in the specific ICA. The impacts of the pulsatile blood stream on the high-risk region are also explained. Wall shear Stress (WSS) and Oscillatory shear index (OSI) factors are also compared in different blood viscosities and coiling conditions. According to our study, the hematocrit test (Hct) effect is evident (25% reduction in maximum WSS) in the two first stages (maximum acceleration and peak systolic). Our findings present that reduction of porosity from 0.89 to 0.79 would decrease maximum WSS by about 8% in both HCT conditions.
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Affiliation(s)
- Ali Rostamian
- grid.467532.10000 0004 4912 2930Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, Iran
| | - Keivan Fallah
- Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, Iran.
| | - Yasser Rostamiyan
- grid.467532.10000 0004 4912 2930Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, Iran
| | - Javad Alinejad
- grid.467532.10000 0004 4912 2930Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, Iran
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10
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Sheidani A, Barzegar Gerdroodbary M, Poozesh A, Sabernaeemi A, Salavatidezfouli S, Hajisharifi A. Influence of the coiling porosity on the risk reduction of the cerebral aneurysm rupture: computational study. Sci Rep 2022; 12:19082. [PMID: 36352253 PMCID: PMC9646831 DOI: 10.1038/s41598-022-23745-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 11/04/2022] [Indexed: 11/11/2022] Open
Abstract
The formation and progress of cerebral aneurysm is highly associated with hemodynamic factors and blood flow feature. In this study, comprehensive efforts are done to investigate the blood hemodynamic effects on the creation and growth of the Internal Carotid Artery. The computational fluid dynamic method is used for the visualization of the bloodstream inside the aneurysm. Transitional, non-Newtonian and incompressible conditions are considered for solving the Navier-Stokes equation to achieve the high-risk region on the aneurysm wall. OSI and WSS of the aneurysm wall are compared within different blood flow stages. The effects of blood viscosity and coiling treatment on these factors are presented in this work. Our study shows that in male patients (HCT = 0.45), changing the porosity of coiling from 0.89 with 0.79 would decreases maximum OSI up to 75% (in maximum acceleration). However, this effect is limited to about 45% for female patients (HCT = 0.35).
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Affiliation(s)
- Armin Sheidani
- grid.4643.50000 0004 1937 0327Mechanical Engineering Department, Politecnico di Milano, Milan, Italy
| | - M. Barzegar Gerdroodbary
- grid.411496.f0000 0004 0382 4574Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
| | - Amin Poozesh
- grid.411976.c0000 0004 0369 2065Department of Aerospace Engineering, K.N. Toosi University of Technology, Tehran, Iran
| | - Amir Sabernaeemi
- grid.5371.00000 0001 0775 6028Department of Space, Earth and Environment, Chalmers University of Technology, Gothenburg, Sweden
| | - Sajad Salavatidezfouli
- grid.5970.b0000 0004 1762 9868Mathematics Area, MathLab, International School for Advanced Studies (SISSA), Trieste, Italy
| | - Arash Hajisharifi
- grid.5970.b0000 0004 1762 9868Mathematics Area, MathLab, International School for Advanced Studies (SISSA), Trieste, Italy
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11
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Xu X, Zhang Z, Abudupataer M, Yang F, Wang C, Zhu K, Tong J. Mechanical characterization and material modeling of ascending aortic aneurysm with different bicuspid aortic cusp fusion morphologies. J Mech Behav Biomed Mater 2022; 132:105295. [DOI: 10.1016/j.jmbbm.2022.105295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/27/2022] [Accepted: 05/21/2022] [Indexed: 10/18/2022]
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12
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Xiao N, Genet M, Khaja M, Desai KR. Antithrombotic Therapy after Deep Venous Intervention. Semin Intervent Radiol 2022; 39:357-363. [PMID: 36406025 PMCID: PMC9671684 DOI: 10.1055/s-0042-1757340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Chronic deep venous disease (CVD) can result in significant morbidity and impact on quality of life due to a spectrum of symptoms, including lower extremity edema, venous claudication, and venous ulcers. CVD can be secondary to both thrombotic and nonthrombotic disease processes, including postthrombotic syndrome from prior deep vein thrombosis (DVT) or iliac vein compression syndrome. Endovascular therapy has become a mainstay therapy for CVD patients, with venous stent placement frequently performed. However, the management of anticoagulation following venous stent placement is not well-studied, with no large trials or consensus guidelines establishing an optimal regimen. The current knowledge gap in antithrombotic therapy is magnified by heterogeneity in practice and data collection, along with incomplete reporting in available studies. Furthermore, most published datasets are antiquated in the setting of rapid evolution in technique and technology available for deep venous intervention. Herein, we summarize the current available literature and offer an approach to anticoagulation and antiplatelet management following deep venous intervention for CVD.
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Affiliation(s)
- Nicholas Xiao
- Division of Interventional Radiology, Department of Radiology, Northwestern University, Chicago, Illinois
| | - Matthew Genet
- Division of Interventional Radiology, Department of Radiology, Northwestern University, Chicago, Illinois
| | - Minhaj Khaja
- Division of Interventional Radiology, Department of Radiology, University of Virginia, Charlottesville, Virginia
| | - Kush R. Desai
- Division of Interventional Radiology, Department of Radiology, Northwestern University, Chicago, Illinois
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13
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Abstract
The aorta contributes to cardiovascular physiology and function. Understanding biomechanics in health, disease, and after aortic interventions will facilitate optimization of perioperative patient care.
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14
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Cikach FS, Germano E, Roselli EE, Svensson LG. Ascending aorta mechanics and dimensions in aortopathy – from science to application. Indian J Thorac Cardiovasc Surg 2022; 38:7-13. [PMID: 35463697 PMCID: PMC8980982 DOI: 10.1007/s12055-020-01092-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/04/2020] [Indexed: 10/22/2022] Open
Abstract
The ascending aorta has a unique microstructure and biomechanical properties that allow it to absorb energy during systole and return energy during diastole (Windkessel effect). Derangements in aortic architecture can result in changes to biomechanics and inefficiencies in function. Ultimately biomechanical failure may occur resulting in aortic dissection or rupture. By measuring aortic biomechanics with either in vivo or ex vivo methods, one may be able to predict tissue failure in patients with aortic disease such as aneurysms. An understanding of the biomechanical changes that lead to these tissue-level failures may help guide therapy, disease surveillance, surgical intervention, and aid in the development of new treatments for this deadly condition.
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15
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Xuan Y, D'Souza SN, Wang Z, Pierre AS, Lawton JS, Ge L, Tseng EE. Patient-Specific Biomechanics in Marfan Ascending Thoracic Aortic Aneurysms. Ann Thorac Surg 2021; 114:1367-1375. [PMID: 34416226 DOI: 10.1016/j.athoracsur.2021.07.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 06/11/2021] [Accepted: 07/12/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Guidelines for Sinus of Valsalva-thoracic aortic aneurysms (SOV-TAA) in Marfan syndrome recommend size-based criteria for elective surgical repair. Biomechanics may provide a better prediction of dissection risk than diameter. Our aim was to determine magnitudes of wall stress in the aortic root of Marfan patients using finite element analyses. METHODS Forty-six Marfan patients underwent patient-specific 3D SOV-TAA geometry reconstruction using imaging data. Finite element analyses were performed to determine wall stress distributions at SOV, sinotubular junction (STJ), and ascending aorta (AscAo) at systole. RESULTS Peak circumferential stresses were 432.8±111kPa, 408.1±88.3kPa, and 321.9±83.8kPa at the SOV, STJ, and AscAo, respectively with significant differences between SOV and AscAo (p<3.08E-07), and STJ and AscAo (p<2.26E-06). Peak longitudinal wall stresses were 352±73.9kPa, 277.5±89.5kPa, and 200.6±81kPa at SOV, STJ, and AscAo, respectively with significant differences between SOV and STJ (p< 6.01E-06), SOV and AscAo (p< 9.79E-13), and STJ and AscAo (p< 3.34E-07). Diameter was not correlated to wall stresses. Comparison of wall stresses in aneurysm <5cm vs ≥5cm and <4.5cm vs ≥4.5 showed no significant differences in wall stresses in the circumferential or longitudinal direction. CONCLUSIONS Peak wall stresses in Marfan SOV-TAA were greatest in SOV than STJ than AscAo. Diameter was poorly correlated to peak stresses such that current guidelines with 5cm cutoff had significant overlap in peak stresses in patients with <5cm vs ≥5cm. Use of patient-specific Marfan aneurysm models may identify patients with high wall stresses and small aneurysms who could benefit from earlier surgical repair to prevent aortic dissection.
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Affiliation(s)
- Yue Xuan
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Sara N D'Souza
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Zhongjie Wang
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Alejandro Suarez Pierre
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Jennifer S Lawton
- Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins Hospital, Baltimore, Maryland
| | - Liang Ge
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, California
| | - Elaine E Tseng
- Division of Adult Cardiothoracic Surgery, Department of Surgery, University of California San Francisco and San Francisco VA Medical Center, San Francisco, California.
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16
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Li D, Yuan D, Peng L, Zheng T, Fan Y. The characteristics of distal tears affect false lumen thrombosis rate after thoracic endovascular aortic repair for acute type B dissection. Interact Cardiovasc Thorac Surg 2021; 33:755-762. [PMID: 34125231 DOI: 10.1093/icvts/ivab166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/25/2021] [Accepted: 05/03/2021] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVES A low false lumen thrombosis rate (FLTR) is common in patients with type B aortic dissection after they have undergone thoracic endovascular aortic repair, which indicates a poor long-term prognosis. This study aimed to establish a quantitative linear regression model to predict false lumen (FL) thrombosis accurately using morphological parameters. METHODS In this retrospective study, we included 59 patients diagnosed with acute type B aortic dissection between 2014 and 2017. Morphological parameters were measured. Univariable and multivariable linear regression analyses were performed, and a linear regression model relating FLTR with the number of re-entry tears was proposed. Ten patients were further chosen to validate the linear relationship, and idealized aortic dissection models were adopted for haemodynamic analysis. RESULTS Only the total area and number of re-entry tears were negatively correlated with FL thrombosis (P < 0.001). Moreover, based on the univariable regression, the number of re-entry tears played a more crucial role in FLTR (R2 = 0.509 vs R2 = 0.298), and the linear relationship model was created as follows: thrombosis rate (%) = -11.25 × distal tear number + 105.24. This model was perfectly matched in 10 patients (concordance correlation coefficient = 0.880, P = 0.947). Moreover, when the total area of re-entry tears was constant, the net blood flow increased rapidly with an increase in the tear count. CONCLUSIONS The number of re-entry tears could be a crucial related factor of FL thrombosis; the larger the number of re-entry tears is, the lower the possibility of thrombosis is.
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Affiliation(s)
- Da Li
- Department of Applied Mechanics, Sichuan University, Chengdu, China
| | - Ding Yuan
- Department of Vascular Surgery of West China Hospital, Sichuan University, Chengdu, China
| | - Liqing Peng
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Tinghui Zheng
- Department of Applied Mechanics, Sichuan University, Chengdu, China
| | - Yubo Fan
- Beijing Advanced Innovation Center of Biomedical Engineering, Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China
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17
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Intra-Operative Video-Based Measurement of Biaxial Strains of the Ascending Thoracic Aorta. Biomedicines 2021; 9:biomedicines9060670. [PMID: 34207976 PMCID: PMC8230589 DOI: 10.3390/biomedicines9060670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/31/2021] [Accepted: 06/08/2021] [Indexed: 11/17/2022] Open
Abstract
Local biaxial deformation measurements are essential for the in-depth investigation of tissue properties and remodeling of the ascending thoracic aorta, particularly in aneurysm formation. Current clinical imaging modalities pose limitations around the resolution and tracking of anatomical markers. We evaluated a new intra-operative video-based method to assess local biaxial strains of the ascending thoracic aorta. In 30 patients undergoing open-chest surgery, we obtained repeated biaxial strain measurements, at low- and high-pressure conditions. Precision was very acceptable, with coefficients of variation for biaxial strains remaining below 20%. With our four-marker arrangement, we were able to detect significant local differences in the longitudinal strain as well as in circumferential strain. Overall, the magnitude of strains we obtained (range: 0.02–0.05) was in line with previous reports using other modalities. The proposed method enables the assessment of local aortic biaxial strains and may enable new, clinically informed mechanistic studies using biomechanical modeling as well as mechanobiological profiling.
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18
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Qiu P, Li Y, Liu K, Qin J, Ye K, Chen T, Lu X. Prescreening and treatment of aortic dissection through an analysis of infinite-dimension data. BioData Min 2021; 14:24. [PMID: 33794946 PMCID: PMC8015064 DOI: 10.1186/s13040-021-00249-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/14/2021] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Aortic dissection (AD) is one of the most catastrophic aortic diseases associated with a high mortality rate. In contrast to the advances in most cardiovascular diseases, both the incidence and in-hospital mortality rate of AD have experienced deviant increases over the past 20 years, highlighting the need for fresh prospects on the prescreening and in-hospital treatment strategies. METHODS Through two cross-sectional studies, we adopt image recognition techniques to identify pre-disease aortic morphology for prior diagnoses; assuming that AD has occurred, we employ functional data analysis to determine the optimal timing for BP and HR interventions to offer the highest possible survival rate. RESULTS Compared with the healthy control group, the aortic centerline is significantly more slumped for the AD group. Further, controlling patients' blood pressure and heart rate according to the likelihood of adverse events can offer the highest possible survival probability. CONCLUSIONS The degree of slumpness is introduced to depict aortic morphological changes comprehensively. The morphology-based prediction model is associated with an improvement in the predictive accuracy of the prescreening of AD. The dynamic model reveals that blood pressure and heart rate variations have a strong predictive power for adverse events, confirming this model's ability to improve AD management.
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Affiliation(s)
- Peng Qiu
- Department of Vascular Surgery, Shanghai Ninth People’s Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Big Data Research Lab, University of Waterloo, Waterloo, Canada
| | - Yixuan Li
- Big Data Research Lab, University of Waterloo, Waterloo, Canada
- Department of Economics, University of Waterloo, Waterloo, Canada
- Stoppingtime (Shanghai) BigData & Technology Co. Ltd., Shanghai, China
| | - Kai Liu
- Big Data Research Lab, University of Waterloo, Waterloo, Canada
- School of Mathematical and Computational Sciences, University of Prince Edward Island, Charlottetown, Canada
| | - Jinbao Qin
- Department of Vascular Surgery, Shanghai Ninth People’s Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Kaichuang Ye
- Department of Vascular Surgery, Shanghai Ninth People’s Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Tao Chen
- Big Data Research Lab, University of Waterloo, Waterloo, Canada
- Department of Economics, University of Waterloo, Waterloo, Canada
- Senior Research Fellow of Labor and Worklife Program, Harvard University, Cambridge, USA
| | - Xinwu Lu
- Department of Vascular Surgery, Shanghai Ninth People’s Hospital Affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
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19
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Plonek T, Rylski B, Nawrocki P, Beyersdorf F, Jasinski M, Kuliczkowski W. Systolic stretching of the ascending aorta. Arch Med Sci 2021; 17:25-30. [PMID: 33488852 PMCID: PMC7811307 DOI: 10.5114/aoms.2019.82997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/08/2017] [Indexed: 01/16/2023] Open
Abstract
INTRODUCTION Longitudinal stretching of the aorta due to systolic heart motion contributes to the stress in the wall of the ascending aorta. The objective of this study was to assess longitudinal systolic stretching of the aorta and its correlation with the diameters of the ascending aorta and the aortic root. MATERIAL AND METHODS Aortographies of 122 patients were analyzed. The longitudinal systolic stretching of the aorta caused by the contraction of the heart during systole and the maximum dimensions of the aortic root and ascending aorta were measured in all patients. RESULTS The maximum dimension of the aortic root was on average 34.9 ±4.5 mm and the mean diameter of the ascending aorta was 33.9 ±5.4 mm. The systolic aortic stretching negatively correlated with age (r = -0.49, p < 0.001) and the diameter of the tubular ascending aorta (r = -0.44, p < 0.001). There was no significant correlation between the stretching and the dimension of the aortic root (r = -0.11, p = 0.239). There was a statistically significant (p < 0.001) difference in the longitudinal aortic stretching values between patients with a normal aortic valve (10.6 ±3.1 mm) and an aortic valve pathology (8.0 ±3.2 mm in all patients with an aortic valve pathology; 7.5 ±4.3 mm in isolated aortic stenosis, 8.5 ±2.9 mm in the case of isolated insufficiency, 8.2 ±2.8 mm for valves that were both stenotic and insufficient). CONCLUSIONS Systolic aortic stretching negatively correlates with the diameter of the tubular ascending aorta and the age of the patients, and does not correlate with the diameter of the aortic root. It is lower in patients with an aortic valve pathology.
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Affiliation(s)
- Tomasz Plonek
- Department of Cardiac Surgery, Wroclaw Medical University, Wroclaw, Poland
| | - Bartosz Rylski
- Department of Cardio-vascular Surgery, Heart Centre Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Pawel Nawrocki
- Department of Cardiac Surgery, Wroclaw Medical University, 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 Surgery, Wroclaw Medical University, Wroclaw, Poland
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20
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Xiao N, Desai KR. Antithrombotic Therapy after Venous Stent Placement. VASCULAR AND ENDOVASCULAR REVIEW 2020. [DOI: 10.15420/ver.2020.06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Chronic deep venous disease (CVD) affects millions of Americans and can result in significant morbidity, such as debilitating lower extremity oedema, venous claudication, and in severe cases, venous ulcers. CVD can be caused by thrombotic and non-thrombotic disease processes, such as deep venous thrombosis and iliac compression syndrome. Recently, endovascular intervention with percutaneous transluminal angioplasty and venous stent placement has become the mainstay therapy for these patients, with several studies demonstrating its safety and efficacy. However, anticoagulation management following venous stent placement is largely unstudied, and there are no large randomised controlled trials or official guidelines establishing an optimal regimen. Most published studies are plagued with data heterogeneity and incomplete reporting. This is further complicated by rapidly evolving improvements in technique and dedicated devices in endovenous intervention. In this article, the authors discuss the current literature to date and offer an approach to anticoagulation and antiplatelet management following venous stent placement in CVD.
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Affiliation(s)
| | - Kush R Desai
- Department of Radiology, Northwestern University, Chicago, IL, US
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21
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Collard M, Sutphin PD, Kalva SP, Majdalany BS, Collins JD, Eldrup-Jorgensen J, Francois CJ, Ganguli S, Gunn AJ, Kendi AT, Khaja MS, Obara P, Reis SP, Vijay K, Dill KE. ACR Appropriateness Criteria ® Abdominal Aortic Aneurysm Follow-up (Without Repair). J Am Coll Radiol 2020; 16:S2-S6. [PMID: 31054747 DOI: 10.1016/j.jacr.2019.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 02/07/2019] [Indexed: 10/26/2022]
Abstract
Abdominal aortic aneurysm (AAA) is defined as aneurysmal dilation of the abdominal aorta to 3 cm or greater. A high degree of morbidity and mortality is associated with AAA rupture, and imaging surveillance plays an essential role in mitigating the risk of rupture. Aneurysm size and growth rate are factors associated with the risk of rupture, thus surveillance imaging studies must be accurate and reproducible to characterize aneurysm size. Ultrasound, CT angiography, and MR angiography provide an accurate and reproducible assessment of size, while radiographs and aortography provide limited evaluation. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
| | - Michael Collard
- Research Author, UT Southwestern Medical Center, Dallas, Texas
| | | | | | - Bill S Majdalany
- Panel Vice-Chair, University of Michigan Health System, Ann Arbor, Michigan
| | | | - Jens Eldrup-Jorgensen
- Tufts University School of Medicine, Boston, Massachusetts; Society for Vascular Surgery
| | | | | | - Andrew J Gunn
- University of Alabama at Birmingham, Birmingham, Alabama
| | | | | | - Piotr Obara
- Loyola University Medical Center, Maywood, Illinois
| | | | | | - Karin E Dill
- Specialty Chair, UMass Memorial Medical Center, Worcester, Massachusetts
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22
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Rong LQ, Palumbo MC, Rahouma M, Lopes AJ, Devereux RB, Kim J, Girardi LN, Gaudino M, Weinsaft JW. Descending aortic strain quantification by intra-operative transesophageal echocardiography: Multimodality validation via cardiovascular magnetic resonance. Echocardiography 2020; 37:1820-1827. [PMID: 32909633 DOI: 10.1111/echo.14851] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/06/2020] [Accepted: 08/18/2020] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Whereas cardiac magnetic resonance (CMR) imaging provides high temporal resolution imaging of aortic distensibility (strain), transesophageal echocardiography (TEE) is widely used for intra-operative aortic imaging and provides a clinical alternative for aortic assessment. We tested intra-operative global circumferential aortic strain (GCS) measured on TEE in relation to the reference of CMR-derived strain among patients undergoing surgical graft repair of ascending aortic aneurysms. METHODS CMR (3T) was prospectively performed in patients scheduled for aortic repair. TEE was performed intra-operatively; images were co-localized with MRI. GCS on CMR and TEE was quantified independently, blinded to results of the other modality. RESULTS 25 patients (54 ± 10 year-old, 88% male) were studied, inclusive of 13 genetically mediated and 12 degenerative aneurysms: CMR and TEE were performed within 12 ± 9 days. Pulse pressure (PP)-adjusted descending aortic TEE-derived GCS strongly correlated with cine-CMR-derived GCS (r = .75, P = .002) though absolute GCS and PP-adjusted values were slightly lower (5.40 ± 1.11 vs 6.49 ± 1.43% and 11.55 ± 3.04 vs 13.99 ± 4.53%, respectively). Similarly, TEE yielded slightly lower end-diastolic area (EDA [5.1 ± 1.7 cm2 vs 5.8 ± 1.3 cm2 , P = .004]) and end-systolic area (ESA [6.1 ± 1.9 cm2 vs 6.5 ± 1.7 cm2 , P = .10]), with significant correlations between the two modalities (r = .73, .76, P < .05 for all). CONCLUSIONS This exploratory study supports feasibility of TEE for assessing aortic GCS in a surgical at-risk population, as well as magnitude of agreement between intra-operative TEE and preoperative CMR. We found that there is a significant correlation between GCS and EDA and ESA aortic areas, but that TEE-derived parameters underestimated CMR values by a small but significant amount.
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Affiliation(s)
- Lisa Q Rong
- Department of Anesthesiology, Weill Cornell Medicine/New York Presbyterian Hospital, New York, NY, USA
| | - Maria C Palumbo
- Department of Cardiology/Medicine, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Mohammed Rahouma
- Department of Cardiothoracic Surgery, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Alexandra J Lopes
- Department of Anesthesiology, Weill Cornell Medicine/New York Presbyterian Hospital, New York, NY, USA
| | - Richard B Devereux
- Department of Cardiology/Medicine, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Jiwon Kim
- Department of Cardiology/Medicine, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Leonard N Girardi
- Department of Cardiothoracic Surgery, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Mario Gaudino
- Department of Cardiothoracic Surgery, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
| | - Jonathan W Weinsaft
- Department of Cardiology/Medicine, Weill Cornell Medicine/New York Presbyterian, New York, NY, USA
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23
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Theoretical and Numerical Analysis of Mechanical Behaviors of a Metamaterial-Based Shape Memory Polymer Stent. Polymers (Basel) 2020; 12:polym12081784. [PMID: 32784996 PMCID: PMC7463968 DOI: 10.3390/polym12081784] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/27/2020] [Accepted: 08/03/2020] [Indexed: 11/28/2022] Open
Abstract
Shape memory polymers (SMPs) have gained much attention in biomedical fields due to their good biocompatibility and biodegradability. Researches have validated the feasibility of shape memory polymer stent in treatment of vascular blockage. Nevertheless, the actual application of SMP stents is still in infancy. To improve the mechanical performance of SMP stent, a new geometric model based on metamaterial is proposed in this study. To verify the feasibility and mechanical behavior of this type of stent, buckling analysis, and in vivo expansion performance of SMP stent are simulated. Numerical results exhibit that stent of a smaller radius behaves a higher critical buckling load and smaller buckling displacement. Besides, a smaller contact area with vessel and smaller implanted stress are observed compared with traditional stents. This suggests that this SMP stent attributes to a reduced vascular restenosis. To characterize the radial strength of SMP stent, an analytical solution is derived by the assumption that the deformation of stent is mainly composed of bending and stretch. The radial strength of SMP stent is assessed in form of radial force. Analytical results reveal that radial strength is depended on the radius of stent and periodic numbers of unit cell in circumferential direction.
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24
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Ismaguilova A, Martufi G, Gregory AJ, Appoo JJ, Herget EJ, Kotha V, Di Martino ES. Multidimensional Analysis of Descending Aortic Growth After Acute Type A Aortic Dissection. Ann Thorac Surg 2020; 111:615-621. [PMID: 32504610 DOI: 10.1016/j.athoracsur.2020.04.064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 03/26/2020] [Accepted: 04/10/2020] [Indexed: 01/16/2023]
Abstract
BACKGROUND After repair of acute type A aortic dissection, typical geometric variables of conventional aortic surveillance focus on maximum diameter and its rate of growth, potentially missing important geometric changes elsewhere. We determined additional information provided by a semiautomated, 3-dimensional (3D), nonlinear growth model of the descending thoracic aorta after repair of type A aortic dissection. METHODS Computed tomographic angiography data were retrospectively collected after hemiarch repair of type A aortic dissection. The descending aorta was systematically reconstructed to generate a 3D model made up of individual segments. The baseline and follow-up diameters were measured semiautomatically for each segment, and the nonlinear interval growth was determined. RESULTS The fastest growing segment expanded at a rate of 3.8 mm/y (interquartile range, 2.2 to 5.4 mm/y) vs 0.6 mm/y (interquartile range, -0.3 to 1.7 mm/y) when measured at the original site of maximum diameter (P < .01). The maximum baseline diameter was a poor predictor of location with fastest growth (r = 0.10, P > .1). Using the society recommended growth limits, a greater proportion of patients would be considered "at risk" when assessed by our method vs conventional surveillance measures. CONCLUSIONS Our model identifies areas of rapid aortic growth after repair of type A dissection that would likely be missed using current surveillance techniques. The increased precision, resolution, and reproducibility provided by our technique may improve on limitations of current surveillance techniques, provide novel geometric data on aortic remodeling, and contribute to the pursuit of a comprehensive patient-specific approach to aortic risk stratification.
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Affiliation(s)
- Alina Ismaguilova
- Biomedical Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Giampaolo Martufi
- Department of Civil Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Alexander J Gregory
- Department of Anesthesiology, Perioperative and Pain Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Jehangir J Appoo
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada; Section of Cardiac Surgery, Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Eric J Herget
- Department of Radiology, Foothills Medical Center, Calgary, Alberta, Canada
| | - Vamshi Kotha
- Department of Radiology, Foothills Medical Center, Calgary, Alberta, Canada
| | - Elena S Di Martino
- Biomedical Engineering, University of Calgary, Calgary, Alberta, Canada; Department of Civil Engineering, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.
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Gode S, Akinci O, Ustunısık CT, Sen O, Kadirogulları E, Aksu T, Ersoy B, Gurbak I, Duman ZM, Erentug V. The role of the angle of the ascending aortic curvature on the development of type A aortic dissection: ascending aortic angulation and dissection. Interact Cardiovasc Thorac Surg 2020; 29:615-620. [PMID: 31203369 DOI: 10.1093/icvts/ivz144] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/29/2019] [Accepted: 05/14/2019] [Indexed: 12/27/2022] Open
Abstract
OBJECTIVES Type A aortic dissection (TAD), which consists of an intimal tear in the aorta, necessitates emergency surgery. Various risk factors related to aortic dissection have been defined in the literature. According to our hypothesis, a narrower angle of ascending aortic curvature (AAAC) may be an additional risk factor in relation to aortic dissection due to the increased force applied to the aortic wall. METHODS Patients undergoing ascending aortic surgery due to an ascending aortic aneurysm (AsAA) (n = 105) and patients undergoing such surgery because of the occurrence of TAD (n = 101) were enrolled in this study. The AAAC was measured using Cobb's method; the measurements were made on all patients by just 1 cardiovascular radiologist using 3-dimensional computerized tomographic imaging. This measurement was made indirectly by using the aortic valve and brachiocephalic artery to avoid obtaining misleading data as a result of distortions due to dissection. A statistical comparison was also performed relating the traditional risk factors for TAD to other clinical and echocardiographic parameters: the diameter of the ascending aorta and the AAAC. RESULTS The AAAC was found to be narrower statistically in the TAD group (α = 76.2° ± 17.5°) than it was in the AsAA group (α = 92.9° ± 13°) (P < 0.001). Furthermore, mean ascending aortic diameter (P = 0.019), the presence of a bicuspid aorta (P = 0.007) and aortic valve stenosis (P = 0.005) were higher in the AsAA group. According to multivariable analyses, a narrower AAAC is a significant predictor for the development of TAD (odds ratio 0.93, 95% confidence interval 0.91-0.95; P < 0.001). Overall hospital mortality from various causes including stroke, myocardial infarction, bleeding or renal failure was 13% in the TAD group and 7% in the AsAA group. CONCLUSIONS According to this study, the AAAC was significantly smaller in aortic dissection patients than in aortic aneurysm patients. This may be related to higher shear stress and elevated pressure on the ascending aorta in patients with a narrower AAAC. Thus, a narrower AAAC may be an additional risk factor in the development of TAD. Therefore, we may need to be more careful in terms of looking for the development of aortic dissection in patients with narrower AAAC.
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Affiliation(s)
- Safa Gode
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Okan Akinci
- Department of Radiology, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Cigdem Tel Ustunısık
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Onur Sen
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Ersin Kadirogulları
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Timucin Aksu
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Burak Ersoy
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Ismail Gurbak
- Department of Cardiology, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Zihni Mert Duman
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
| | - Vedat Erentug
- Department of Cardiovascular Surgery, Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey
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Comparison of microstructural alterations in the proximal aorta between aortic stenosis and regurgitation. J Thorac Cardiovasc Surg 2020; 162:1684-1695. [DOI: 10.1016/j.jtcvs.2020.03.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 02/24/2020] [Accepted: 03/03/2020] [Indexed: 12/27/2022]
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Bäumler K, Vedula V, Sailer AM, Seo J, Chiu P, Mistelbauer G, Chan FP, Fischbein MP, Marsden AL, Fleischmann D. Fluid-structure interaction simulations of patient-specific aortic dissection. Biomech Model Mechanobiol 2020; 19:1607-1628. [PMID: 31993829 DOI: 10.1007/s10237-020-01294-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/14/2020] [Indexed: 12/01/2022]
Abstract
Credible computational fluid dynamic (CFD) simulations of aortic dissection are challenging, because the defining parallel flow channels-the true and the false lumen-are separated from each other by a more or less mobile dissection membrane, which is made up of a delaminated portion of the elastic aortic wall. We present a comprehensive numerical framework for CFD simulations of aortic dissection, which captures the complex interplay between physiologic deformation, flow, pressures, and time-averaged wall shear stress (TAWSS) in a patient-specific model. Our numerical model includes (1) two-way fluid-structure interaction (FSI) to describe the dynamic deformation of the vessel wall and dissection flap; (2) prestress and (3) external tissue support of the structural domain to avoid unphysiologic dilation of the aortic wall and stretching of the dissection flap; (4) tethering of the aorta by intercostal and lumbar arteries to restrict translatory motion of the aorta; and a (5) independently defined elastic modulus for the dissection flap and the outer vessel wall to account for their different material properties. The patient-specific aortic geometry is derived from computed tomography angiography (CTA). Three-dimensional phase contrast magnetic resonance imaging (4D flow MRI) and the patient's blood pressure are used to inform physiologically realistic, patient-specific boundary conditions. Our simulations closely capture the cyclical deformation of the dissection membrane, with flow simulations in good agreement with 4D flow MRI. We demonstrate that decreasing flap stiffness from [Formula: see text] to [Formula: see text] kPa (a) increases the displacement of the dissection flap from 1.4 to 13.4 mm, (b) decreases the surface area of TAWSS by a factor of 2.3, (c) decreases the mean pressure difference between true lumen and false lumen by a factor of 0.63, and (d) decreases the true lumen flow rate by up to 20% in the abdominal aorta. We conclude that the mobility of the dissection flap substantially influences local hemodynamics and therefore needs to be accounted for in patient-specific simulations of aortic dissection. Further research to accurately measure flap stiffness and its local variations could help advance future CFD applications.
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Affiliation(s)
- Kathrin Bäumler
- 3D and Quantitative Imaging Laboratory, Department of Radiology, Stanford University, Stanford, CA, 94305, USA.
| | - Vijay Vedula
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
| | - Anna M Sailer
- 3D and Quantitative Imaging Laboratory, Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Jongmin Seo
- Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, 94305, USA
| | - Peter Chiu
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, 94305, USA
| | - Gabriel Mistelbauer
- Department of Simulation and Graphics, University of Magdeburg, Magdeburg, Germany
| | - Frandics P Chan
- 3D and Quantitative Imaging Laboratory, Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Michael P Fischbein
- Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, 94305, USA
| | - Alison L Marsden
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Dominik Fleischmann
- 3D and Quantitative Imaging Laboratory, Department of Radiology, Stanford University, Stanford, CA, 94305, USA
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Qiu Y, Wang Y, Fan Y, Peng L, Liu R, Zhao J, Yuan D, Zheng T. Role of intraluminal thrombus in abdominal aortic aneurysm ruptures: A hemodynamic point of view. Med Phys 2019; 46:4263-4275. [PMID: 31206182 DOI: 10.1002/mp.13658] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/27/2019] [Accepted: 06/05/2019] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Intraluminal thrombus (ILTs) are found in most abdominal aortic aneurysms (AAAs) of clinically relevant size; however, the role of ILTs in AAA ruptures remains unclear. This study investigated the role of the presence and thickness of ILTs in AAA ruptures by analyzing the hemodynamic environment in ruptured AAAs (RAAAs). METHODS Three-dimensional reconstructions from computed tomography scans were performed, and 13 RAAA cases were categorized into a no-ILT group, a thin-layered ILT group (thickness < 3 mm), and a thick-layered ILT group. The hemodynamic features of the RAAAs were assessed using computational fluid dynamics simulation. RESULTS The thin- and thick-layered ILT groups showed significant differences in aneurysm diameters (P < 0.05). The three types of AAAs ruptured at different flow regions, with different hemodynamic features: (a) the no-ILT AAAs ruptured at regions of flow recirculation where velocity and wall shear stresses (WSSs) were close to zero; (b) the thin-layered ILT AAAs ruptured at sites at which the dominant flow impinged the wall; and (c) the thick-layered ILT AAAs ruptured at the border of the dominant flow channel and recirculation zone where the flow velocity and pressure changed dramatically. CONCLUSIONS Hemodynamic characteristics influence the rupture mechanisms of particular AAAs differently on the basis of the presence and thickness of ILTs. Recirculation flows and low WSSs may have negative effects by inducing local rupture or positive effects by promoting the formation of thin-layered ILTs. However, eccentrically located thick-layered ILTs may increase the rupture risk of small AAAs because of their location in the sac lumen, which results in chaotic flow patterns and rapid increases in flow resistance.
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Affiliation(s)
- Yue Qiu
- Department of Applied Mechanics, Sichuan University, Chengdu, 610065, China
| | - Yi Wang
- Department of Computer Science, Sichuan University of Science and Engineering, Zigong, Sichuan, 643000, China
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, P. R. China
| | - Liqing Peng
- The Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Rong Liu
- Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong, China
| | - Jichun Zhao
- Department Vascular Surgery of West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Ding Yuan
- Department Vascular Surgery of West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Tinghui Zheng
- Department of Applied Mechanics, Sichuan University, Chengdu, 610065, China
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Auricchio F, Conti M, Romarowski RM, de Beaufort HW, Grassi V, Trimarchi S. Computational tools for thoracic endovascular aortic repair planning. ITALIAN JOURNAL OF VASCULAR AND ENDOVASCULAR SURGERY 2019. [DOI: 10.23736/s1824-4777.18.01386-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Deveja RP, Iliopoulos DC, Kritharis EP, Angouras DC, Sfyris D, Papadodima SA, Sokolis DP. Effect of Aneurysm and Bicuspid Aortic Valve on Layer-Specific Ascending Aorta Mechanics. Ann Thorac Surg 2018; 106:1692-1701. [DOI: 10.1016/j.athoracsur.2018.05.071] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/10/2018] [Accepted: 05/22/2018] [Indexed: 10/28/2022]
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Haslach HW, Gipple J, Taylor B, Rabin J. Comparison of aneurysmal and non-pathologic human ascending aortic tissue in shear. Clin Biomech (Bristol, Avon) 2018; 58:49-56. [PMID: 30015206 DOI: 10.1016/j.clinbiomech.2018.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/22/2018] [Accepted: 07/02/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND The mechanical properties of the aorta may provide some guidance to cardiovascular surgeons treating aortic disease. While tensile tests are traditional, recent work suggests that shear is important in aortic dissection. Characterizing the differences or similarities in the mechanical shear stress response of non-pathologic human ascending aortic tissue and of tissue that has remodeled to become aneurysmal contributes to understanding the differences in behavior of the two tissues. METHODS Fresh non-pathological and aneurysmal tissue acquired from the operating room is deformed in translational shear at approximately physiological rates to 67% deformation followed by stress relaxation to allow comparison of their mechanical behavior. Aneurysmal tissue is tested at 1 mm/s or 12 mm/s and normal tissue at 12 mm/s. The deformation is either in the circumferential or longitudinal direction for a total of 48 specimens. FINDINGS The shear response at 12 mm/s in non-pathological and aneurysmal tissue is similar in the circumferential direction but different in the longitudinal direction. Tissue type accounts for up to 30% of the variation in the longitudinal direction. The aneurysmal tissue response is rate-dependent. Both tissues exhibit significant shear stress relaxation. INTERPRETATION Remodeling to create the aneurysm modifies the bond strength between collagen fibers and the extracellular matrix. The time-dependent response is probably due to interstitial fluid behavior. Thoracic surgeons must use caution in applying aortic stress values in the literature because they depend on the deformation rate.
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Affiliation(s)
- Henry W Haslach
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA.
| | - Jenna Gipple
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
| | - Bradley Taylor
- Division of Cardiac Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joseph Rabin
- R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, MD, USA
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Takei Y, Itatani K, Miyazaki S, Shibasaki I, Fukuda H. Four-dimensional flow magnetic resonance imaging analysis before and after thoracic endovascular aortic repair of chronic type B aortic dissection. Interact Cardiovasc Thorac Surg 2018; 28:413-420. [DOI: 10.1093/icvts/ivy271] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/27/2018] [Accepted: 07/31/2018] [Indexed: 01/24/2023] Open
Affiliation(s)
- Yusuke Takei
- Department of Cardiac and Vascular Surgery, Dokkyo Medical University Hospital, Mibu-Machi, Tochigi, Japan
| | | | | | - Ikuko Shibasaki
- Department of Cardiac and Vascular Surgery, Dokkyo Medical University Hospital, Mibu-Machi, Tochigi, Japan
| | - Hirotsugu Fukuda
- Department of Cardiac and Vascular Surgery, Dokkyo Medical University Hospital, Mibu-Machi, Tochigi, Japan
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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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Schwein A, Georg Y, Lejay A, Nicolini P, Hartung O, Contassot D, Thaveau F, Heim F, Chakfe N. Endovascular Treatment for Venous Diseases: Where are the Venous Stents? Methodist Debakey Cardiovasc J 2018; 14:208-213. [PMID: 30410651 PMCID: PMC6217567 DOI: 10.14797/mdcj-14-3-208] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
There is a growing need for dedicated endovascular devices to treat pathologies affecting the venous system. However, because of a lack of research into venous diseases and treatments, the optimal design, material, and mechanical properties of venous stents remain unknown. Development of the ideal venous stent should be based on a thorough understanding of the underlying venous pathology. There are multiple venous diseases that differ from each other depending on their location (iliocaval, superior vena cava), mechanism (thrombotic versus nonthrombotic lesions), and chronicity. Thus, it is likely that stent material, design, and features should differ according to each underlying disease. From a mechanical point of view, the success of a venous stent hinges on its ability to resist crushing (which requires high global and local radial rigidity) and to match with the compliant implant environment (which requires high flexibility). Device oversizing, textile coverage, and drug coating are additional features that should be considered in the context of venous diseases rather than directly translated from the arterial world. This review examines the unique forces affecting venous stents, the problems with using arterial devices to treat venous pathologies, preliminary results of a study comparing crush resistance of commercially available laser-cut stents with a novel braided stent design, and its applicability to venous interventions.
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Affiliation(s)
- Adeline Schwein
- UNIVERSITY HOSPITAL OF STRASBOURG, FRANCE
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
| | - Yannick Georg
- UNIVERSITY HOSPITAL OF STRASBOURG, FRANCE
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
| | - Anne Lejay
- UNIVERSITY HOSPITAL OF STRASBOURG, FRANCE
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
| | | | | | | | - Fabien Thaveau
- UNIVERSITY HOSPITAL OF STRASBOURG, FRANCE
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
| | - Frédéric Heim
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
- LABORATOIRE DE PHYSIQUE ET MÉCANIQUE TEXTILE, ENSISA, MULHOUSE, FRANCE
| | - Nabil Chakfe
- UNIVERSITY HOSPITAL OF STRASBOURG, FRANCE
- GROUPE EUROPÉEN DE RECHERCHE SUR LES PROTHÈSES APPLIQUÉES À LA CHIRURGIE VASCULAIRE (GEPROVAS), STRASBOURG, FRANCE
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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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Gregory AJ, Di Martino E, Fedak PWM. Aortic diameter: The beginning of the end of an era. J Thorac Cardiovasc Surg 2018; 156:513-514. [PMID: 29510930 DOI: 10.1016/j.jtcvs.2018.01.079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 10/18/2022]
Affiliation(s)
- Alexander J Gregory
- Department of Anesthesiology, Perioperative and Pain Medicine, Cumming School of Medicine, University of Calgary, Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada
| | - Elena Di Martino
- Department of Civil Engineering, Centre for Bioengineering Research and Education, University of Calgary, Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada
| | - Paul W M Fedak
- Section of Cardiac Surgery, Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada.
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A non-invasive methodology for ATAA rupture risk estimation. J Biomech 2018; 66:119-126. [DOI: 10.1016/j.jbiomech.2017.11.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 10/13/2017] [Accepted: 11/09/2017] [Indexed: 01/05/2023]
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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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Aortic Valve Pathology as a Predictive Factor for Acute Aortic Dissection. Ann Thorac Surg 2017; 104:1340-1348. [DOI: 10.1016/j.athoracsur.2017.02.076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/16/2017] [Accepted: 02/24/2017] [Indexed: 11/21/2022]
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Strbac V, Pierce D, Rodriguez-Vila B, Vander Sloten J, Famaey N. Rupture risk in abdominal aortic aneurysms: A realistic assessment of the explicit GPU approach. J Biomech 2017; 56:1-9. [DOI: 10.1016/j.jbiomech.2017.02.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 02/13/2017] [Accepted: 02/16/2017] [Indexed: 10/20/2022]
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Biomechanical Characterization of Ascending Aortic Aneurysms. Biomech Model Mechanobiol 2016; 16:705-720. [DOI: 10.1007/s10237-016-0848-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 10/17/2016] [Indexed: 12/26/2022]
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Biaxial rupture properties of ascending thoracic aortic aneurysms. Acta Biomater 2016; 42:273-285. [PMID: 27345137 DOI: 10.1016/j.actbio.2016.06.028] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 05/11/2016] [Accepted: 06/22/2016] [Indexed: 12/22/2022]
Abstract
UNLABELLED Although hundreds of samples obtained from ascending thoracic aortic aneurysms (ATAA) of patients undergoing elective surgical repair have already been characterized biomechanically, their rupture properties were always derived from uniaxial tensile tests. Due to their bulge shape, ATAAs are stretched biaxially in vivo. In order to understand the biaxial rupture of ATAAs, our group developed a novel methodology based on bulge inflation and full-field optical measurements. The objective of the current paper is threefold. Firstly, we will review the failure properties (maximum stress, maximum stretch) obtained by bulge inflation testing on a cohort of 31 patients and compare them with failure properties obtained by uniaxial tension in a previously published study. Secondly, we will investigate the relationship between the failure properties and the age of patients, showing that patients below 55years of age display significantly higher strength. Thirdly, we will define a rupture risk based on the extensibility of the tissue and we will show that this rupture risk is strongly correlated with the physiological elastic modulus of the tissue independently of the age, ATAA diameter or the aortic valve phenotype of the patient. STATEMENT OF SIGNIFICANCE Despite their medical importance, rupture properties of ascending thoracic aortic aneurysms (ATAA) subjected to biaxial tension were inexistent in the literature. In order to address this lack, our group developed a novel methodology based on bulge inflation and full-field optical measurements. Here we report rupture properties obtained with this methodology on 31 patients. It is shown for the first time that rupture occurs when the stretch applied to ATAAs reaches the maximum extensibility of the tissue and that this maximum extensibility correlates strongly with the elastic properties. The outcome is a better detection of at-risk individuals for elective surgical repair.
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Biomechanics of the Thoracic Aorta: Complexity and Reliability. Ann Thorac Surg 2016; 102:1028. [PMID: 27549527 DOI: 10.1016/j.athoracsur.2016.01.108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 01/20/2016] [Accepted: 01/28/2016] [Indexed: 11/21/2022]
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Di Martino ES. Reply. Ann Thorac Surg 2016; 102:1028-1029. [PMID: 27549528 DOI: 10.1016/j.athoracsur.2016.05.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 11/28/2022]
Affiliation(s)
- Elena S Di Martino
- Department of Civil Engineering, Centre for Bioenginering Research and Education, Libin Cardiovascular Institute, University of Calgary, 2500 University Dr NW, Calgary, AB T2L0W2, Canada.
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