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Cai Z, Satyanarayana G, Song P, Zhao F, You S, Liu Z, Mu J, Ding Y, He B, Zou MH. Regulation of Ptbp1-controlled alternative splicing of pyruvate kinase muscle by Liver kinase b1 governs vascular smooth muscle cell plasticity in vivo. Cardiovasc Res 2024:cvae187. [PMID: 39189621 DOI: 10.1093/cvr/cvae187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 04/12/2024] [Accepted: 08/25/2024] [Indexed: 08/28/2024] Open
Abstract
AIMS Vascular smooth muscle cell (VSMC) plasticity is a state in which VSMCs undergo phenotypic switching from a quiescent contractile phenotype into other functionally distinct phenotypes. Although emerging evidence suggest that VSMC plasticity plays critical roles in the development of vascular diseases, little is known about the key determinant for controlling VSMC plasticity and fate. METHODS AND RESULTS We found that smooth muscle cell-specific deletion of Lkb1 in tamoxifen-inducible Lkb1flox/flox; Myh11-Cre/ERT2 mice spontaneously and progressively induced aortic/arterial dilation, aneurysm, rupture, and premature death. Single-cell RNA sequencing and imaging-based lineage tracing showed that Lkb1-deficient VSMCs transdifferentiated gradually from early modulated VSMCs to fibroblast-like and chondrocyte-like cells, leading to ossification and blood-vessel rupture. Mechanistically, Lkb1 regulates polypyrimidine tract binding protein 1 (Ptbp1) expression and controls alternative splicing of pyruvate kinase muscle (PKM) isoforms 1 and 2. Lkb1 loss in VSMC results in an increased PKM2/PKM1 ratio and alters the metabolic profile by promoting aerobic glycolysis. Treatment with PKM2 activator TEPP-46 rescues VSMC transformation and aortic dilation in Lkb1flox/flox; Myh11-Cre/ERT2 mice. Furthermore, we found that Lkb1 expression decreased in human aortic aneurysm tissue compared to control tissue, along with changes in markers of VSMC fate. CONCLUSIONS Lkb1, via its regulation of Ptbp1-dependent alterative splicing of PKM, maintains VSMC in contractile states by suppressing VSMC plasticity.
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Affiliation(s)
- Zhaohua Cai
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, China
| | - Ganesh Satyanarayana
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Ping Song
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Fujie Zhao
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Shaojin You
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, China
| | - Zhixue Liu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Jing Mu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Ye Ding
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
| | - Ben He
- Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, China
| | - Ming-Hui Zou
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, 30303
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Valente R, Mourato A, Xavier J, Sousa P, Domingues T, Tavares P, Avril S, Tomás A, Fragata J. Experimental Protocols to Test Aortic Soft Tissues: A Systematic Review. Bioengineering (Basel) 2024; 11:745. [PMID: 39199703 PMCID: PMC11351783 DOI: 10.3390/bioengineering11080745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 07/18/2024] [Indexed: 09/01/2024] Open
Abstract
Experimental protocols are fundamental for quantifying the mechanical behaviour of soft tissue. These data are crucial for advancing the understanding of soft tissue mechanics, developing and calibrating constitutive models, and informing the development of more accurate and predictive computational simulations and artificial intelligence tools. This paper offers a comprehensive review of experimental tests conducted on soft aortic tissues, employing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, based on the Scopus, Web of Science, IEEE, Google Scholar and PubMed databases. This study includes a detailed overview of the test method protocols, providing insights into practical methodologies, specimen preparation and full-field measurements. The review also briefly discusses the post-processing methods applied to extract material parameters from experimental data. In particular, the results are analysed and discussed providing representative domains of stress-strain curves for both uniaxial and biaxial tests on human aortic tissue.
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Affiliation(s)
- Rodrigo Valente
- UNIDEMI, Department of Mechanical and Industrial Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; (R.V.); (A.M.)
| | - André Mourato
- UNIDEMI, Department of Mechanical and Industrial Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; (R.V.); (A.M.)
| | - José Xavier
- UNIDEMI, Department of Mechanical and Industrial Engineering, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal; (R.V.); (A.M.)
- Intelligent Systems Associate Laboratory, LASI, 4800-058 Guimarães, Portugal
| | - Pedro Sousa
- INEGI, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (P.S.); (P.T.)
| | - Tiago Domingues
- INEGI, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (P.S.); (P.T.)
| | - Paulo Tavares
- INEGI, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (P.S.); (P.T.)
| | - Stéphane Avril
- Mines Saint-Etienne, University of Lyon, Inserm, Sainbiose U1059, Campus Santé Innovation, 10, rue de la Marandière, 42270 Saint-Priest-en-Jarez, France;
| | - António Tomás
- Department of Cardiothoracic Surgery, Santa Marta Hospital, Rua de Santa Marta, 1169-024 Lisboa, Portugal; (A.T.); (J.F.)
| | - José Fragata
- Department of Cardiothoracic Surgery, Santa Marta Hospital, Rua de Santa Marta, 1169-024 Lisboa, Portugal; (A.T.); (J.F.)
- Department of Surgery and Human Morphology, NOVA Medical School, Universidade NOVA de Lisboa, Campo Mártires da Pátria, 1169-056 Lisboa, Portugal
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Zu HL, Zhuang PP, Peng Y, Peng C, Peng C, Zhu ZJ, Yao Y, Yue J, Wang QS, Zhou WH, Wang HY. Dual-Drug Nanomedicine Assembly with Synergistic Anti-Aneurysmal Effects via Inflammation Suppression and Extracellular Matrix Stabilization. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2402141. [PMID: 38953313 DOI: 10.1002/smll.202402141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 06/03/2024] [Indexed: 07/04/2024]
Abstract
Abdominal aortic aneurysm (AAA) represents a critical cardiovascular condition characterized by localized dilation of the abdominal aorta, carrying a significant risk of rupture and mortality. Current treatment options are limited, necessitating novel therapeutic approaches. This study investigates the potential of a pioneering nanodrug delivery system, RAP@PFB, in mitigating AAA progression. RAP@PFB integrates pentagalloyl glucose (PGG) and rapamycin (RAP) within a metal-organic-framework (MOF) structure through a facile assembly process, ensuring remarkable drug loading capacity and colloidal stability. The synergistic effects of PGG, a polyphenolic antioxidant, and RAP, an mTOR inhibitor, collectively regulate key players in AAA pathogenesis, such as macrophages and smooth muscle cells (SMCs). In macrophages, RAP@PFB efficiently scavenges various free radicals, suppresses inflammation, and promotes M1-to-M2 phenotype repolarization. In SMCs, it inhibits apoptosis and calcification, thereby stabilizing the extracellular matrix and reducing the risk of AAA rupture. Administered intravenously, RAP@PFB exhibits effective accumulation at the AAA site, demonstrating robust efficacy in reducing AAA progression through multiple mechanisms. Moreover, RAP@PFB demonstrates favorable biosafety profiles, supporting its potential translation into clinical applications for AAA therapy.
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Affiliation(s)
- Hong Lin Zu
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
- The Key Laboratory of Advanced Interdisciplinary Studies, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Pei Pei Zhuang
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Ying Peng
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Chao Peng
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Cheng Peng
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Zi Jia Zhu
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Ye Yao
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Jie Yue
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Qing Shan Wang
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
| | - Wen Hu Zhou
- Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, 410013, China
| | - Hai Yang Wang
- Department of Vascular Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
- The Key Laboratory of Advanced Interdisciplinary Studies, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, China
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Mansouri M, Therasse E, Montagnon E, Zhan YO, Lessard S, Roy A, Boucher LM, Steinmetz O, Aslan E, Tang A, Chartrand-Lefebvre C, Soulez G. CT analysis of aortic calcifications to predict abdominal aortic aneurysm rupture. Eur Radiol 2024; 34:3903-3911. [PMID: 37999728 DOI: 10.1007/s00330-023-10429-1] [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: 02/05/2023] [Revised: 09/12/2023] [Accepted: 09/28/2023] [Indexed: 11/25/2023]
Abstract
BACKGROUND Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. The goal was to assess whether aortic calcification distribution could better predict AAA rupture through machine learning and LASSO regression. METHODOLOGY In this retrospective study, 80 patients treated for a ruptured AAA between January 2001 and August 2018 were matched with 80 non-ruptured patients based on maximal AAA diameter, age, and sex. Calcification volume and dispersion, morphologic, and clinical variables were compared between both groups using a univariable analysis with p = 0.05 and multivariable analysis through machine learning and LASSO regression. We used AUC for machine learning and odds ratios for regression to measure performance. RESULTS Mean age of patients was 74.0 ± 8.4 years and 89% were men. AAA diameters were equivalent in both groups (80.9 ± 17.5 vs 79.0 ± 17.3 mm, p = 0.505). Ruptured aneurysms contained a smaller number of calcification aggregates (18.0 ± 17.9 vs 25.6 ± 18.9, p = 0.010) and were less likely to have a proximal neck (45.0% vs 76.3%, p < 0.001). In the machine learning analysis, 5 variables were associated to AAA rupture: proximal neck, antiplatelet use, calcification number, Euclidian distance between calcifications, and standard deviation of the Euclidian distance. A follow-up LASSO regression was concomitant with the findings of the machine learning analysis regarding calcification dispersion but discordant on calcification number. CONCLUSION There might be more to AAA calcifications that what is known in the present literature. We need larger prospective studies to investigate if indeed, calcification dispersion affects rupture risk. CLINICAL RELEVANCE STATEMENT Ruptured aneurysms are possibly more likely to have their calcification volume concentrated in a smaller geographical area. KEY POINTS • Abdominal aortic aneurysm (AAA) rupture prediction based on sex and diameter could be improved. • For a given calcification volume, AAAs with well-distributed calcification clusters could be less likely to rupture. • A machine learning model including AAA calcifications better predicts rupture compared to a model based solely on maximal diameter and sex alone, although it might be prone to overfitting.
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Affiliation(s)
- Mohamed Mansouri
- Department of Radiology, McGill University Health Center (MUHC), Montréal, Québec, Canada
- Department of Diagnostic Radiology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Eric Therasse
- Department of Radiology, Centre Hospitalier de L'Université de Montréal (CHUM), 1051 Rue Sanguinet, Montreal, QC, H2X 3E4, Canada
- Department of Radiology, Radiation Oncology and Nuclear Medicine, Université de Montréal, Montréal, Québec, Canada
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada
| | - Emmanuel Montagnon
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada
| | - Ying Olivier Zhan
- Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Simon Lessard
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada
| | - Aubert Roy
- Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Louis-Martin Boucher
- Department of Radiology, McGill University Health Center (MUHC), Montréal, Québec, Canada
- Department of Diagnostic Radiology, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Oren Steinmetz
- Department of Vascular Surgery, McGill University Health Center (MUHC), Montréal, Québec, Canada
- Department of Vascular Surgery, Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Emre Aslan
- Faculty of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - An Tang
- Department of Radiology, Centre Hospitalier de L'Université de Montréal (CHUM), 1051 Rue Sanguinet, Montreal, QC, H2X 3E4, Canada
- Department of Radiology, Radiation Oncology and Nuclear Medicine, Université de Montréal, Montréal, Québec, Canada
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada
| | - Carl Chartrand-Lefebvre
- Department of Radiology, Centre Hospitalier de L'Université de Montréal (CHUM), 1051 Rue Sanguinet, Montreal, QC, H2X 3E4, Canada
- Department of Radiology, Radiation Oncology and Nuclear Medicine, Université de Montréal, Montréal, Québec, Canada
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada
| | - Gilles Soulez
- Department of Radiology, Centre Hospitalier de L'Université de Montréal (CHUM), 1051 Rue Sanguinet, Montreal, QC, H2X 3E4, Canada.
- Department of Radiology, Radiation Oncology and Nuclear Medicine, Université de Montréal, Montréal, Québec, Canada.
- Laboratory of Clinical Imaging Processing, Centre Hospitalier de L'Université de Montréal (CHUM) Research Center (CRCHUM), Montréal, Québec, Canada.
- Institute of Biomedical Engineering, Université de Montréal, Montréal, Québec, Canada.
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Arbănaşi EM, Russu E, Arbănaşi EM, Ciucanu CC, Mureșan AV, Suzuki S, Chirilă TV. Effect of Ultraviolet Radiation on the Enzymolytic and Biomechanical Profiles of Abdominal Aortic Adventitia Tissue. J Clin Med 2024; 13:633. [PMID: 38276139 PMCID: PMC10817471 DOI: 10.3390/jcm13020633] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/10/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
BACKGROUND The abdominal aortic aneurysm (AAA) is defined as an increase in aortic diameter by more than 50% and is associated with a high risk of rupture and mortality without treatment. The aim of this study is to analyze the role of aortic adventitial collagen photocrosslinking by UV-A irradiation on the biomechanical profile of the aortic wall. METHODS This experimental study is structured in two parts: the first part includes in vitro uniaxial biomechanical evaluation of porcine adventitial tissue subjected to either short-term elastolysis or long-term collagenolysis in an attempt to duplicate two extreme situations as putative stages of aneurysmal degeneration. In the second part, we included biaxial biomechanical evaluation of in vitro human abdominal aortic adventitia and human AAA adventitia specimens. Biomechanical profiles were examined for porcine and human aortic tissue before and after irradiation with UV-A light (365 nm wavelength). RESULTS On the porcine aortic sample, the enhancing effect of irradiation was evident both on the tissue subjected to elastolysis, which had a high collagen-to-elastin ratio, and on the tissue subjected to prolonged collagenolysis despite being considerably depleted in collagen. Further, the effect of irradiation was conclusively demonstrated in the human adventitia samples, where significant post-irradiation increases in Cauchy stress (longitudinal axis: p = 0.001, circumferential axis: p = 0.004) and Young's modulus (longitudinal axis: p = 0.03, circumferential axis: p = 0.004) were recorded. Moreover, we have a stronger increase in the strengthening of the AAA adventitia samples following the exposure to UV-A irradiation (p = 0.007) and a statistically significant but not very important increase (p = 0.021) regarding the stiffness in the circumferential axis. CONCLUSIONS The favorable effect of UV irradiation on the strength and stiffness of degraded aortic adventitia in experimental situations mimicking early and later stages of aneurysmal degeneration is essential for the development and potential success of procedures to prevent aneurysmal ruptures. The experiments on human normal and aneurysmal adventitial tissue confirmed the validity and potential success of a procedure based on exposure to UV-A radiation.
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Affiliation(s)
- Emil-Marian Arbănaşi
- Doctoral School of Medicine and Pharmacy, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures (UMFST), 540142 Targu Mures, Romania; (E.-M.A.); (E.-M.A.); (C.C.C.)
- Clinic of Vascular Surgery, Mures County Emergency Hospital, 540136 Targu Mures, Romania;
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania; (S.S.); (T.V.C.)
| | - Eliza Russu
- Clinic of Vascular Surgery, Mures County Emergency Hospital, 540136 Targu Mures, Romania;
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania
| | - Eliza-Mihaela Arbănaşi
- Doctoral School of Medicine and Pharmacy, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures (UMFST), 540142 Targu Mures, Romania; (E.-M.A.); (E.-M.A.); (C.C.C.)
| | - Constantin Claudiu Ciucanu
- Doctoral School of Medicine and Pharmacy, George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures (UMFST), 540142 Targu Mures, Romania; (E.-M.A.); (E.-M.A.); (C.C.C.)
- Clinic of Vascular Surgery, Mures County Emergency Hospital, 540136 Targu Mures, Romania;
| | - Adrian Vasile Mureșan
- Clinic of Vascular Surgery, Mures County Emergency Hospital, 540136 Targu Mures, Romania;
- Department of Vascular Surgery, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania
| | - Shuko Suzuki
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania; (S.S.); (T.V.C.)
- Queensland Eye Institute, South Brisbane, QLD 4101, Australia
| | - Traian V. Chirilă
- Centre for Advanced Medical and Pharmaceutical Research (CCAMF), George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania; (S.S.); (T.V.C.)
- Queensland Eye Institute, South Brisbane, QLD 4101, Australia
- Faculty of Medicine, George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, 540139 Targu Mures, Romania
- School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD 4001, Australia
- Australian Institute of Bioengineering and Nanotechnology (AIBN), University of Queensland, St. Lucia, QLD 4072, Australia
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Hu S, Qiu S, Wan B, Ruan L, Zhu L, Wang S, Su L, Guo Q, Xu J, Wei Y. Association Between Serum Uric Acid and Abdominal Aortic Calcification in Adults Aged 40 to 80 years: A Retrospective Cross-Sectional Study. Angiology 2024:33197241227275. [PMID: 38212979 DOI: 10.1177/00033197241227275] [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: 01/13/2024]
Abstract
There are numerous causes of abdominal aortic calcification (AAC), among which the relationship between serum uric acid and AAC still needs to be investigated further. The aim of this research was to ascertain whether serum uric acid is correlated with AAC. Our study included 3007 participants. We described the study population characteristics and utilized univariate analysis, stratified analysis, multiple equation regression analysis, smoothed curve fitting, and threshold effects analysis. AAC Total 24 score is used to reflect the range of aortic calcification at each vertebral level. As serum uric acid increased, the AAC Total 24 score first decreased and then increased. The fold point is located when serum uric is at 3.5 mg/dL. After adjusting for 16 covariates, the beta values for the groups with moderate and high serum uric acid levels were 0.34 and 0.53, respectively, compared with the low serum uric acid tertile group (P < .05). Our research indicates a negative correlation between serum acid level and AAC when serum uric acid <3.5 mg/dl, but it is positively correlated with the formation of AAC when serum uric acid >3.5 mg/dl.
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Affiliation(s)
- Sheng Hu
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Shengyu Qiu
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Bingen Wan
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Liancheng Ruan
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lingxiao Zhu
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Siling Wang
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lang Su
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Qiang Guo
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Jianjun Xu
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yiping Wei
- Department of Thoracic Surgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
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Ushakova O, Ravakhah K. Massive Calcified Abdominal Aortic Aneurysm Presenting as Low Back Pain. Cureus 2023; 15:e46406. [PMID: 37927703 PMCID: PMC10621262 DOI: 10.7759/cureus.46406] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2023] [Indexed: 11/07/2023] Open
Abstract
Calcified abdominal aortic aneurysm (CAAA) is a radiological finding that manifests the calcification in the bulged aortic walls. CAAA has high mortality. The presence of calcification as a key player in abdominal aortic aneurysm (AAA) rupture risk was reported in the literature. Factors contributing to a CAAA compared to AAA are age, dyslipidemia, hypertension, diabetes mellitus, genetics, disturbances in calcium-phosphate homeostasis, and smoking. There are a few genetic mutations associated with CAAA as well. Causes of AAA include lipid build-up in the aortic wall, inflammatory diseases, traumas, blood vessel diseases that supply the aortic wall, and connective tissue disorders.
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Affiliation(s)
- Oxana Ushakova
- Internal Medicine, MetroHealth Medical Center, Cleveland, USA
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8
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Hegner A, Wittek A, Derwich W, Huß A, Gámez AJ, Blase C. Using averaged models from 4D ultrasound strain imaging allows to significantly differentiate local wall strains in calcified regions of abdominal aortic aneurysms. Biomech Model Mechanobiol 2023; 22:1709-1727. [PMID: 37405538 PMCID: PMC10511614 DOI: 10.1007/s10237-023-01738-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 06/13/2023] [Indexed: 07/06/2023]
Abstract
Abdominal aortic aneurysms are a degenerative disease of the aorta associated with high mortality. To date, in vivo information to characterize the individual elastic properties of the aneurysm wall in terms of rupture risk is lacking. We have used time-resolved 3D ultrasound strain imaging to calculate spatially resolved in-plane strain distributions characterized by mean and local maximum strains, as well as indices of local variations in strains. Likewise, we here present a method to generate averaged models from multiple segmentations. Strains were then calculated for single segmentations and averaged models. After registration with aneurysm geometries based on CT-A imaging, local strains were divided into two groups with and without calcifications and compared. Geometry comparison from both imaging modalities showed good agreement with a root mean squared error of 1.22 ± 0.15 mm and Hausdorff Distance of 5.45 ± 1.56 mm (mean ± sd, respectively). Using averaged models, circumferential strains in areas with calcifications were 23.2 ± 11.7% (mean ± sd) smaller and significantly distinguishable at the 5% level from areas without calcifications. For single segmentations, this was possible only in 50% of cases. The areas without calcifications showed greater heterogeneity, larger maximum strains, and smaller strain ratios when computed by use of the averaged models. Using these averaged models, reliable conclusions can be made about the local elastic properties of individual aneurysm (and long-term observations of their change), rather than just group comparisons. This is an important prerequisite for clinical application and provides qualitatively new information about the change of an abdominal aortic aneurysm in the course of disease progression compared to the diameter criterion.
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Affiliation(s)
- Achim Hegner
- Personalized Biomedical Engineering Lab, Frankfurt University of Applied Sciences, Frankfurt am Main, Germany
- Department of Mechanical Engineering and Industrial Design, School of Engineering, University of Cadiz, Cadiz, Spain
| | - Andreas Wittek
- Personalized Biomedical Engineering Lab, Frankfurt University of Applied Sciences, Frankfurt am Main, Germany
| | - Wojciech Derwich
- Department of Vascular and Endovascular Surgery, Goethe University Hospital, Frankfurt am Main, Germany
| | - Armin Huß
- Personalized Biomedical Engineering Lab, Frankfurt University of Applied Sciences, Frankfurt am Main, Germany
| | - Antonio J. Gámez
- Department of Mechanical Engineering and Industrial Design, School of Engineering, University of Cadiz, Cadiz, Spain
| | - Christopher Blase
- Personalized Biomedical Engineering Lab, Frankfurt University of Applied Sciences, Frankfurt am Main, Germany
- Cell and Vascular Mechanics, Goethe University, Frankfurt am Main, Germany
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9
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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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10
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Arslan AC, Salman HE. Effect of Intraluminal Thrombus Burden on the Risk of Abdominal Aortic Aneurysm Rupture. J Cardiovasc Dev Dis 2023; 10:233. [PMID: 37367398 DOI: 10.3390/jcdd10060233] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
Abdominal aortic aneurysm (AAA) is a critical health disorder, where the abdominal aorta dilates more than 50% of its normal diameter. Enlargement in abdominal aorta alters the hemodynamics and flow-induced forces on the AAA wall. Depending on the flow conditions, the hemodynamic forces on the wall may result in excessive mechanical stresses that lead to AAA rupture. The risk of rupture can be predicted using advanced computational techniques such as computational fluid dynamics (CFD) and fluid-structure interaction (FSI). For a reliable rupture risk assessment, formation of intraluminal thrombus (ILT) and uncertainty in arterial material properties should be taken into account, mainly due to the patient-specific differences and unknowns in AAAs. In this study, AAA models are computationally investigated by performing CFD simulations combined with FSI analysis. Various levels of ILT burdens are artificially generated in a realistic AAA geometry, and the peak effective stresses are evaluated to elucidate the effect of material models and ILT formation. The results indicate that increasing the ILT burden leads to lowered effective stresses on the AAA wall. The material properties of the artery and ILT are also effective on the stresses; however, these effects are limited compared to the effect of ILT volume in the AAA sac.
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Affiliation(s)
- Aykut Can Arslan
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara 06530, Turkey
| | - Huseyin Enes Salman
- Department of Mechanical Engineering, TOBB University of Economics and Technology, Ankara 06530, Turkey
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11
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Gasser TC, Miller C, Polzer S, Roy J. A quarter of a century biomechanical rupture risk assessment of abdominal aortic aneurysms. Achievements, clinical relevance, and ongoing developments. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023; 39:e3587. [PMID: 35347895 DOI: 10.1002/cnm.3587] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 01/28/2022] [Accepted: 03/03/2022] [Indexed: 05/12/2023]
Abstract
Abdominal aortic aneurysm (AAA) disease, the local enlargement of the infrarenal aorta, is a serious condition that causes many deaths, especially in men exceeding 65 years of age. Over the past quarter of a century, computational biomechanical models have been developed towards the assessment of AAA risk of rupture, technology that is now on the verge of being integrated within the clinical decision-making process. The modeling of AAA requires a holistic understanding of the clinical problem, in order to set appropriate modeling assumptions and to draw sound conclusions from the simulation results. In this article we summarize and critically discuss the proposed modeling approaches and report the outcome of clinical validation studies for a number of biomechanics-based rupture risk indices. Whilst most of the aspects concerning computational mechanics have already been settled, it is the exploration of the failure properties of the AAA wall and the acquisition of robust input data for simulations that has the greatest potential for the further improvement of this technology.
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Affiliation(s)
- T Christian Gasser
- Department of Engineering Mechanics, KTH Royal Institute of Technology, Stockholm, Sweden
- Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Christopher Miller
- Department of Engineering Mechanics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Stanislav Polzer
- Department of Applied Mechanics, VSB-Technical University of Ostrava, Ostrava-Poruba, Czech Republic
| | - Joy Roy
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Vascular Surgery, Karolinska University Hospital, Stockholm, Sweden
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12
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Fletcher AJ, Nash J, Syed MB, Macaskill MG, Tavares AA, Walker N, Salcudean H, Leipsic JA, Lim KH, Madine J, Wallace W, Field M, Newby DE, Bouchareb R, Seidman MA, Akhtar R, Sellers SL. Microcalcification and Thoracic Aortopathy: A Window Into Disease Severity. Arterioscler Thromb Vasc Biol 2022; 42:1048-1059. [PMID: 35770666 PMCID: PMC9311465 DOI: 10.1161/atvbaha.122.317111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Patients with thoracic aortopathy are at increased risk of catastrophic aortic dissection, carrying with it substantial mortality and morbidity. Although granular medial calcinosis (medial microcalcification) has been associated with thoracic aortopathy, its relationship to disease severity has yet to be established. METHODS One hundred one thoracic aortic specimens were collected from 57 patients with thoracic aortopathy and 18 control subjects. Standardized histopathologic scores, immunohistochemistry, and nanoindentation (tissue elastic modulus) were compared with the extent of microcalcification on von Kossa histology and 18F-sodium fluoride autoradiography. RESULTS Microcalcification content was higher in thoracic aortopathy samples with mild (n=28; 6.17 [2.71-10.39]; P≤0.00010) or moderate histopathologic degeneration (n=30; 3.74 [0.87-11.80]; P<0.042) compared with control samples (n=18; 0.79 [0.36-1.90]). Alkaline phosphatase (n=26; P=0.0019) and OPN (osteopontin; n=26; P=0.0045) staining were increased in tissue with early aortopathy. Increasingly severe histopathologic degeneration was related to reduced microcalcification (n=82; Spearman ρ, -0.51; P<0.0001)-a process closely linked with elastin loss (n=82; Spearman ρ, -0.43; P<0.0001) and lower tissue elastic modulus (n=28; Spearman ρ, 0.43; P=0.026).18F-sodium fluoride autoradiography demonstrated good correlation with histologically quantified microcalcification (n=66; r=0.76; P<0.001) and identified areas of focal weakness in vivo. CONCLUSIONS Medial microcalcification is a marker of aortopathy, although progression to severe aortopathy is associated with loss of both elastin fibers and microcalcification.18F-sodium fluoride positron emission tomography quantifies medial microcalcification and is a feasible noninvasive imaging modality for identifying aortic wall disruption with major translational promise.
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Affiliation(s)
- Alexander J. Fletcher
- British Heart Foundation Centre for Cardiovascular Science (A.J.F., J.N., M.B.J.S., N.W., D.E.N.), University of Edinburgh, United Kingdom.,Department of Child Health, University of Glasgow, School of Medicine and Dentistry, United Kingdom (A.J.F.)
| | - Jennifer Nash
- British Heart Foundation Centre for Cardiovascular Science (A.J.F., J.N., M.B.J.S., N.W., D.E.N.), University of Edinburgh, United Kingdom
| | - Maaz B.J. Syed
- British Heart Foundation Centre for Cardiovascular Science (A.J.F., J.N., M.B.J.S., N.W., D.E.N.), University of Edinburgh, United Kingdom
| | - Mark G. Macaskill
- Edinburgh Imaging Facility, Queens Medical Research Institute (M.G.M., A.A.S.T.), University of Edinburgh, United Kingdom
| | - Adriana A.S. Tavares
- Edinburgh Imaging Facility, Queens Medical Research Institute (M.G.M., A.A.S.T.), University of Edinburgh, United Kingdom
| | - Niki Walker
- British Heart Foundation Centre for Cardiovascular Science (A.J.F., J.N., M.B.J.S., N.W., D.E.N.), University of Edinburgh, United Kingdom.,Scottish Adult Congenital Cardiology Service, Golden Jubilee National Hospital, Clydebank, Glasgow, United Kingdom (N.W.)
| | - Hannah Salcudean
- Department of Radiology, Division of Cardiology, Cardiovascular Translational Lab at the Centre for Heart Lung Innovation, St. Paul’s Hospital and University of British Columbia, Vancouver, Canada (H.S., J.A.L., S.L.S.)
| | - Jonathon A. Leipsic
- Department of Radiology, Division of Cardiology, Cardiovascular Translational Lab at the Centre for Heart Lung Innovation, St. Paul’s Hospital and University of British Columbia, Vancouver, Canada (H.S., J.A.L., S.L.S.)
| | - Kelvin H.H. Lim
- Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, United Kingdom (K.H.H.L.)
| | - Jillian Madine
- Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences (J.M., M.F., R.A.), University of Liverpool, United Kingdom.,Liverpool Centre for Cardiovascular Sciences (J.M.), University of Liverpool, United Kingdom
| | - William Wallace
- Division of Pathology (W.W.), University of Edinburgh, United Kingdom
| | - Mark Field
- Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences (J.M., M.F., R.A.), University of Liverpool, United Kingdom.,Department of Cardiothoracic Surgery, Liverpool Heart and Chest Hospital (LCCS), United Kingdom (M.F.)
| | - David E. Newby
- British Heart Foundation Centre for Cardiovascular Science (A.J.F., J.N., M.B.J.S., N.W., D.E.N.), University of Edinburgh, United Kingdom
| | - Rihab Bouchareb
- Department of Medicine, Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York, NY (R.B.)
| | - Michael A. Seidman
- Department of Laboratory Medicine and Pathobiology, Toronto General Hospital, Canada (M.A.S.)
| | - Riaz Akhtar
- Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences (J.M., M.F., R.A.), University of Liverpool, United Kingdom.,Department of Mechanical, Materials and Aerospace Engineering, School of Engineering, University of Liverpool, United Kingdom (R.A.)
| | - Stephanie L. Sellers
- Department of Radiology, Division of Cardiology, Cardiovascular Translational Lab at the Centre for Heart Lung Innovation, St. Paul’s Hospital and University of British Columbia, Vancouver, Canada (H.S., J.A.L., S.L.S.)
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13
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Minderhoud SCS, Fletcher AJ, MacNaught G, Cadet S, Korteland SA, Kardys I, Rizopoulos D, Slomka P, Newby DE, Roos-Hesselink JW, Walker NL, Semple S, Hirsch A, Dweck MR, Wentzel JJ. Vascular biomechanics and molecular disease activity in the thoracic aorta: a novel imaging method. Eur Heart J Cardiovasc Imaging 2022; 23:1698-1707. [PMID: 35666823 PMCID: PMC9671295 DOI: 10.1093/ehjci/jeac090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/08/2022] [Accepted: 04/28/2022] [Indexed: 12/03/2022] Open
Abstract
AIMS The influence haemodynamics have on vessel wall pathobiology in aortic disease is incomplete. This aim of this study was to develop a repeatable method for assessing the relationship between aortic wall shear stress (WSS) and disease activity by fusing 4D flow cardiovascular magnetic resonance (CMR) with hybrid positron emission tomography (PET). METHODS AND RESULTS As part of an ongoing clinical trial, patients with bicuspid aortic valve (BAV) were prospectively imaged with both 18F-sodium fluoride (18F-NaF) PET, a marker of calcification activity, and 4D flow CMR. We developed novel software allowing accurate 3D co-registration and high-resolution comparison of aortic peak systolic WSS and 18F-NaF PET uptake (maximum tissue-to-background ratio). Intra-observer repeatability of both measurements was determined using Bland-Altman plots and intra-class correlation coefficients (ICCs). The relationship between localized WSS and 18F-NaF uptake was analysed using linear mixed-effect models. Twenty-three patients with BAV (median age 50 [44-55] years, 22% female) were included. Intra-observer repeatability for WSS (ICC = 0.92) and 18F-NaF (ICC = 0.91) measurements obtained within 1.4 ± 0.6 cm2 regions of interest was excellent. On multivariable analysis, 18F-NaF PET uptake was independently and negatively associated with WSS as well as diastolic blood pressure (both P < 0.05), adjusted for age. CONCLUSION Fused assessment of WSS and 18F-NaF PET uptake is feasible and repeatable, demonstrating a clear association between these two factors. This high spatial resolution approach has major potential to advance our understanding of the relationship between vascular haemodynamics and disease activity.
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Affiliation(s)
| | | | - Gillian MacNaught
- Edinburgh Imaging Facility, Queens Medical Research Institute, University of Edinburgh, EH16 4TJ Edinburgh, UK
| | - Sebastien Cadet
- Department of Imaging (Division of Nuclear Cardiology), Cedars-Sinai Medical Centre, CA 90048 Los Angeles, CA, USA
| | - Suze-Anne Korteland
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Isabella Kardys
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Dimitris Rizopoulos
- Department of Biostatistics, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Piotr Slomka
- Department of Imaging (Division of Nuclear Cardiology), Cedars-Sinai Medical Centre, CA 90048 Los Angeles, CA, USA
| | - David E Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Chancellor’s Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK
| | - Jolien W Roos-Hesselink
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Niki L Walker
- Scottish Adult Congenital Cardiac Service, Golden Jubilee National Hospital, G81 4DY Clydebank, UK
| | - Scott Semple
- Edinburgh Imaging Facility, Queens Medical Research Institute, University of Edinburgh, EH16 4TJ Edinburgh, UK
| | - Alexander Hirsch
- Department of Cardiology, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands,Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
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14
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Tashima Y, Iwakoshi S, Inoue T, Nakamura N, Sano T, Kimura N, Inoue T, Adachi K, Yamaguchi A. Aortic Agatston score correlates with the progression of acute type A aortic dissection. PLoS One 2022; 17:e0263881. [PMID: 35148346 PMCID: PMC8836313 DOI: 10.1371/journal.pone.0263881] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 01/28/2022] [Indexed: 12/21/2022] Open
Abstract
Aortic calcification in the tunica media is correlated with aortic stiffness, elastin degradation, and wall shear stress. The study aim was to determine if aortic calcifications influence disease progression in patients with acute type A aortic dissection (ATAAD). We retrospectively reviewed a total of 103 consecutive patients who had undergone surgery for ATAAD at our institution between January 2009 and December 2019. Of these, 85 patients who had preoperatively undergone plain computed tomography angiography (CTA) for evaluation of their aortic calcification were included. Moreover, we assessed the progression of aortic dissection after surgery via postoperative CTA. Using a classification and regression tree to identify aortic Agatston score thresholds predictive of disease progression, the patients were classified into high-score (Agatston score ≥ 3344; n = 36) and low-score (<3344; n = 49) groups. Correlations between aortic Agatston scores and CTA variables were assessed. Higher aortic Agatston scores were significantly correlated with the smaller distal extent of aortic dissection (p < 0.001), larger true lumen areas of the ascending (p = 0.009) and descending aorta (p = 0.002), and smaller false lumen areas of the descending aorta (p = 0.028). Patients in the high-score group were more likely to have DeBakey type II dissection (p = 0.001) and false lumen thrombosis (p = 0.027) than those in the low-score group, thereby confirming the correlations. Aortic dissection in the high-score group was significantly less distally extended (p < 0.001). A higher aortic Agatston score correlates with the larger true lumen area of the ascending and descending aorta and the less distal progression of aortic dissection in patients with ATAAD. Interestingly, the findings before and after surgery were consistent. Hence, aortic Agatston scores are associated with aortic dissection progression and may help predict postoperative residual dissected aorta remodeling.
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Affiliation(s)
- Yasushi Tashima
- Department of Cardiovascular Surgery, Yokosuka General Hospital Uwamachi, Yokosuka, Kanagawa, Japan
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
- * E-mail:
| | | | - Takeshi Inoue
- Department of Radiology, Nara Medical University, Nara, Japan
| | - Noriyuki Nakamura
- Department of Cardiovascular Surgery, Yokosuka General Hospital Uwamachi, Yokosuka, Kanagawa, Japan
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Taichi Sano
- Department of Cardiovascular Surgery, Yokosuka General Hospital Uwamachi, Yokosuka, Kanagawa, Japan
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Naoyuki Kimura
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Takashi Inoue
- Institute for Clinical and Translational Science, Nara Medical University, Kashihara, Japan
| | - Koichi Adachi
- Department of Cardiovascular Surgery, Yokosuka General Hospital Uwamachi, Yokosuka, Kanagawa, Japan
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
| | - Atsushi Yamaguchi
- Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan
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15
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In Vivo Aortic Magnetic Resonance Elastography in Abdominal Aortic Aneurysm: A Validation in an Animal Model. Invest Radiol 2021; 55:463-472. [PMID: 32520516 DOI: 10.1097/rli.0000000000000660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Using maximum diameter of an abdominal aortic aneurysm (AAA) alone for management can lead to delayed interventions or unnecessary urgent repairs. Abdominal aortic aneurysm stiffness plays an important role in its expansion and rupture. In vivo aortic magnetic resonance elastography (MRE) was developed to spatially measure AAA stiffness in previous pilot studies and has not been thoroughly validated and evaluated for its potential clinical value. This study aims to evaluate noninvasive in vivo aortic MRE-derived stiffness in an AAA porcine model and investigate the relationships between MRE-derived AAA stiffness and (1) histopathology, (2) uniaxial tensile test, and (3) burst testing for assessing MRE's potential in evaluating AAA rupture risk. MATERIALS AND METHODS Abdominal aortic aneurysm was induced in 31 Yorkshire pigs (n = 226 stiffness measurements). Animals were randomly divided into 3 cohorts: 2-week, 4-week, and 4-week-burst. Aortic MRE was sequentially performed. Histopathologic analyses were performed to quantify elastin, collagen, and mineral densities. Uniaxial tensile test and burst testing were conducted to measure peak stress and burst pressure for assessing the ultimate wall strength. RESULTS Magnetic resonance elastography-derived AAA stiffness was significantly higher than the normal aorta. Significant reduction in elastin and collagen densities as well as increased mineralization was observed in AAAs. Uniaxial tensile test and burst testing revealed reduced ultimate wall strength. Magnetic resonance elastography-derived aortic stiffness correlated to elastin density (ρ = -0.68; P < 0.0001; n = 60) and mineralization (ρ = 0.59; P < 0.0001; n = 60). Inverse correlations were observed between aortic stiffness and peak stress (ρ = -0.32; P = 0.0495; n = 38) as well as burst pressure (ρ = -0.55; P = 0.0116; n = 20). CONCLUSIONS Noninvasive in vivo aortic MRE successfully detected aortic wall stiffening, confirming the extracellular matrix remodeling observed in the histopathologic analyses. These mural changes diminished wall strength. Inverse correlation between MRE-derived aortic stiffness and aortic wall strength suggests that MRE-derived stiffness can be a potential biomarker for clinically assessing AAA wall status and rupture potential.
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DIAS-NETO M, NEVES E, SOUSA-NUNES F, HENRIQUES-COELHO T, SAMPAIO S. Abdominal aortic aneurysm calcification: trying to identify a reliable semiquantitative method. THE JOURNAL OF CARDIOVASCULAR SURGERY 2021; 62:51-58. [DOI: 10.23736/s0021-9509.18.10132-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Vitásek R, Gossiho D, Polzer S. Sources of inconsistency in mean mechanical response of abdominal aortic aneurysm tissue. J Mech Behav Biomed Mater 2020; 115:104274. [PMID: 33421951 DOI: 10.1016/j.jmbbm.2020.104274] [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: 08/26/2020] [Revised: 11/20/2020] [Accepted: 12/12/2020] [Indexed: 10/22/2022]
Abstract
INTRODUCTION There is a striking difference in the reported mean response of abdominal aortic aneurysm tissue in academic literature depending on the type of tests (uniaxial vs biaxial) performed. In this paper, the hypothesis variability caused by differences in experimental protocols is explored using porcine aortic tissue as a substitute for aneurysmal tissue. METHODS Nine samples of porcine aorta were created and both uniaxial and biaxial tests were performed. Three effects were investigated. (i) Effect of sample (non) preconditioning, (ii) effect of objective function used (normalised vs non-normalised), and (iii) effect of chosen procedure used for mean response calculation: constant averaging (CA) vs fit to averaged response (FAR) vs fit to all data (FAD). Both the overall shape of mean curve and mean initial stiffness were compared. RESULTS (i) Non-preconditioning led to a much stiffer response, and initial stiffness was about three times higher for a non-preconditioned response based on uniaxial data compared to a preconditioned biaxial response. (ii) CA led to a much stiffer response compared to FAR and FAD procedures which gave similar results. (iii) Normalised objective function produced a mean response with six times lower initial stiffness and more pronounced nonlinearity compared to non-normalised objective function. DISCUSSION It is possible to reproduce a mechanically inconsistent response purely by using the chosen experimental protocol. Non-preconditioned data from failure tests should be used for FE simulation of the elastic response of aneurysms. CA should not be used to obtain a mean response.
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Affiliation(s)
- Radek Vitásek
- Department of Applied Mechanics, VSB-Technical University of Ostrava, 17.listopadu 2172/15, Ostrava-Poruba, 708 00, Czech Republic.
| | - Didier Gossiho
- Department of Biomedical Engineering, University of Iowa, 5605 Seamans Center, Iowa City, IA, 52242, USA
| | - Stanislav Polzer
- Department of Applied Mechanics, VSB-Technical University of Ostrava, 17.listopadu 2172/15, Ostrava-Poruba, 708 00, Czech Republic
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18
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Failure properties of abdominal aortic aneurysm tissue are orientation dependent. J Mech Behav Biomed Mater 2020; 114:104181. [PMID: 33153925 DOI: 10.1016/j.jmbbm.2020.104181] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 08/12/2020] [Accepted: 10/23/2020] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Biomechanical rupture risk assessment of abdominal aortic aneurysm (AAA) requires information about failure properties of aneurysmal tissue. There are large differences between reported values. Among others, studies vary in using either axially or circumferentially oriented samples. This study investigates the effect of sample orientation on failure properties. METHODS Aneurysmal tissues from 45 patients (11 females) were harvested during open AAA repair, cut into uniaxial samples (90) and tested mechanically within 3 h. If possible, the samples were cut in both axial (49 samples) and circumferential (41 samples) directions. Wall thickness, First Piola-Kirchhoff strength Pult and ultimate tension Tult were recorded. Influence of sample orientation and other clinical parameters were investigated using non parametric tests. RESULTS Medians of Pult (values 1100 kPa for circumferential vs. 715 kPa for axial direction, p < 10-4) and Tult (17.4 N/cm in circumferential vs. 11.2 N/cm in axial direction, p < 10-4) were significantly higher in circumferential direction. For paired data, the median of difference was 411 kPa (p < 10-3) in Pult and 7.4 N/cm (p < 10-4) in Tult in favor of circumferential direction. CONCLUSIONS In this first study of anisotropy in AAA wall failure properties using paired comparisons, the strength in circumferential orientation was found to be higher than in axial orientation.
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Derwich W, Wittek A, Hegner A, Fritzen CP, Blase C, Schmitz-Rixen T. Comparison of Abdominal Aortic Aneurysm Sac and Neck Wall Motion with 4D Ultrasound Imaging. Eur J Vasc Endovasc Surg 2020; 60:539-547. [DOI: 10.1016/j.ejvs.2020.06.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 05/29/2020] [Accepted: 06/19/2020] [Indexed: 12/28/2022]
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Risk Factors and Mouse Models of Abdominal Aortic Aneurysm Rupture. Int J Mol Sci 2020; 21:ijms21197250. [PMID: 33008131 PMCID: PMC7583758 DOI: 10.3390/ijms21197250] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/19/2020] [Accepted: 08/28/2020] [Indexed: 02/07/2023] Open
Abstract
Abdominal aortic aneurysm (AAA) rupture is an important cause of death in older adults. In clinical practice, the most established predictor of AAA rupture is maximum AAA diameter. Aortic diameter is commonly used to assess AAA severity in mouse models studies. AAA rupture occurs when the stress (force per unit area) on the aneurysm wall exceeds wall strength. Previous research suggests that aortic wall structure and strength, biomechanical forces on the aorta and cellular and proteolytic composition of the AAA wall influence the risk of AAA rupture. Mouse models offer an opportunity to study the association of these factors with AAA rupture in a way not currently possible in patients. Such studies could provide data to support the use of novel surrogate markers of AAA rupture in patients. In this review, the currently available mouse models of AAA and their relevance to the study of AAA rupture are discussed. The review highlights the limitations of mouse models and suggests novel approaches that could be incorporated in future experimental AAA studies to generate clinically relevant results.
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Predictors of Abdominal Aortic Aneurysm Risks. Bioengineering (Basel) 2020; 7:bioengineering7030079. [PMID: 32707846 PMCID: PMC7552640 DOI: 10.3390/bioengineering7030079] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/17/2020] [Accepted: 07/20/2020] [Indexed: 11/16/2022] Open
Abstract
Computational biomechanics via finite element analysis (FEA) has long promised a means of assessing patient-specific abdominal aortic aneurysm (AAA) rupture risk with greater efficacy than current clinically used size-based criteria. The pursuit stems from the notion that AAA rupture occurs when wall stress exceeds wall strength. Quantification of peak (maximum) wall stress (PWS) has been at the cornerstone of this research, with numerous studies having demonstrated that PWS better differentiates ruptured AAAs from non-ruptured AAAs. In contrast to wall stress models, which have become progressively more sophisticated, there has been relatively little progress in estimating patient-specific wall strength. This is because wall strength cannot be inferred non-invasively, and measurements from excised patient tissues show a large spectrum of wall strength values. In this review, we highlight studies that investigated the relationship between biomechanics and AAA rupture risk. We conclude that combining wall stress and wall strength approximations should provide better estimations of AAA rupture risk. However, before personalized biomechanical AAA risk assessment can become a reality, better methods for estimating patient-specific wall properties or surrogate markers of aortic wall degradation are needed. Artificial intelligence methods can be key in stratifying patients, leading to personalized AAA risk assessment.
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22
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Bartstra JW, Mali WPT, Spiering W, de Jong PA. Abdominal aortic calcification: from ancient friend to modern foe. Eur J Prev Cardiol 2020; 28:1386-1391. [PMID: 34647579 DOI: 10.1177/2047487320919895] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/27/2020] [Indexed: 01/16/2023]
Abstract
Background Abdominal aortic calcifications were already ubiquitous in ancient populations from all continents. Although nowadays generally considered as an innocent end stage of stabilised atherosclerotic plaques, increasing evidence suggests that arterial calcifications contribute to cardiovascular risk. In this review we address abdominal aortic calcification from an evolutionary perspective and review the literature on histology, prevalence, risk factors, clinical outcomes and pharmacological interventions of abdominal aortic calcification. Design The design of this study was based on a literature review. Methods Pubmed and Embase were systematically searched for articles on abdominal aortic calcification and its synonyms without language restrictions. Articles with data on histology, prevalence, risk factors clinical outcomes and/or pharmacological interventions were selected. Results Abdominal aortic calcification is highly prevalent in the general population and prevalence and extent increase with age. Prevalence and risk factors differ between males and females and different ethnicities. Risk factors include traditional cardiovascular risk factors and decreased bone mineral density. Abdominal aortic calcification is shown to contribute to arterial stiffness and is a strong predictor of cardiovascular events and mortality. Several therapies to inhibit arterial calcification have been developed and investigated in small clinical trials. Conclusions Abdominal aortic calcification is from all eras and increasingly acknowledged as an independent contributor to cardiovascular disease. Large studies with long follow-up must be carried out to show whether inhibition of abdominal aortic calcification will further reduce cardiovascular risk.
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Affiliation(s)
- Jonas W Bartstra
- Department of Radiology, University Medical Center Utrecht, the Netherlands
| | - Willem PThM Mali
- Department of Radiology, University Medical Center Utrecht, the Netherlands
| | - Wilko Spiering
- Department of Vascular Medicine, University Medical Center Utrecht, the Netherlands
| | - Pim A de Jong
- Department of Radiology, University Medical Center Utrecht, the Netherlands
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23
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Li Z, Zhao Z, Cai Z, Sun Y, Li L, Yao F, Yang L, Zhou Y, Zhu H, Fu Y, Wang L, Fang W, Chen Y, Kong W. Runx2 (Runt-Related Transcription Factor 2)-Mediated Microcalcification Is a Novel Pathological Characteristic and Potential Mediator of Abdominal Aortic Aneurysm. Arterioscler Thromb Vasc Biol 2020; 40:1352-1369. [PMID: 32212850 DOI: 10.1161/atvbaha.119.314113] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Abdominal aortic aneurysms (AAAs) are highly lethal diseases without effective clinical predictors and therapeutic targets. Vascular microcalcification, as detected by fluorine-18-sodium fluoride, has recently been recognized as a valuable indicator in predicting atherosclerotic plaque rupture and AAA expansion. However, whether vascular microcalcification involved in the pathogenesis of AAA remains elusive. Approach and Results: Microcalcification was analyzed in human aneurysmal aortas histologically and in AngII (angiotensin II)-infused ApoE-/- mouse aortas by fluorine-18-sodium fluoride positron emission tomography and X-ray computed tomography scanning in chronological order in live animals. AAA patients' aortic tissue showed markedly enhanced microcalcification in the aortic media within the area proximal to elastic fiber degradation, compared with non-AAA patients. Enhanced fluorine-18-sodium fluoride uptake preceded significant aortic expansion in mice. Microcalcification-positive mice on day 7 of AngII infusion showed dramatic aortic expansion on subsequent days 14 to 28, whereas microcalcification-negative AngII-infused mice and saline-induced mice did not develop AAA. The application of hydroxyapatite, the main component of microcalcification, aggravated AngII-induced AAA formation in vivo. RNA-sequencing analysis of the suprarenal aortas of 4-day-AngII-infused ApoE-/- mice and bioinformatics analysis with ChIP-Atlas database identified the potential involvement of the osteogenic transcriptional factor Runx2 (runt-related transcription factor 2) in AAA. Consistently, vascular smooth muscle cell-specific Runx2 deficiency markedly repressed AngII-induced AAA formation in the ApoE-/- mice compared with the control littermates. CONCLUSIONS Our studies have revealed microcalcification as a novel pathological characteristic and potential mediator of AAA, and targeting microcalcification may represent a promising strategy for AAA prevention and treatment.
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Affiliation(s)
- Zhiqing Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, China (Z.L., Z.C., L.Y., Y.F., W.K.)
| | - Zuoquan Zhao
- Department of Nuclear Medicine (Z.Z., W.F.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Zeyu Cai
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, China (Z.L., Z.C., L.Y., Y.F., W.K.)
| | - Yong Sun
- Department of Pathology, University of Alabama at Birmingham (Y.S., Y.C.)
| | - Li Li
- Department of Pathology, State Key Laboratory of Cardiovascular Disease (L.L.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Fang Yao
- State Key Laboratory of Cardiovascular Disease (F.Y., L.W.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Liu Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, China (Z.L., Z.C., L.Y., Y.F., W.K.)
| | - Yuan Zhou
- Department of Biomedical Informatics, School of Basic Medical Sciences, Peking University, Beijing, China (Y.Z.)
| | - Haibo Zhu
- Fuwai Hospital, National Center for Cardiovascular Diseases, and State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica (H.Z.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Yi Fu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, China (Z.L., Z.C., L.Y., Y.F., W.K.)
| | - Li Wang
- State Key Laboratory of Cardiovascular Disease (F.Y., L.W.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Wei Fang
- Department of Nuclear Medicine (Z.Z., W.F.), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing
| | - Yabing Chen
- Department of Pathology, University of Alabama at Birmingham (Y.S., Y.C.)
| | - Wei Kong
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, China (Z.L., Z.C., L.Y., Y.F., W.K.)
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24
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Paritala PK, Yarlagadda PKDV, Kansky R, Wang J, Mendieta JB, Gu Y, McGahan T, Lloyd T, Li Z. Stress-Relaxation and Cyclic Behavior of Human Carotid Plaque Tissue. Front Bioeng Biotechnol 2020; 8:60. [PMID: 32117939 PMCID: PMC7026010 DOI: 10.3389/fbioe.2020.00060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 01/23/2020] [Indexed: 12/12/2022] Open
Abstract
Atherosclerotic plaque rupture is a catastrophic event that contributes to mortality and long-term disability. A better understanding of the plaque mechanical behavior is essential for the identification of vulnerable plaques pre-rupture. Plaque is subjected to a natural dynamic mechanical environment under hemodynamic loading. Therefore, it is important to understand the mechanical response of plaque tissue under cyclic loading conditions. Moreover, experimental data of such mechanical properties are fundamental for more clinically relevant biomechanical modeling and numerical simulations for risk stratification. This study aims to experimentally and numerically characterize the stress-relaxation and cyclic mechanical behavior of carotid plaque tissue. Instron microtester equipped with a custom-developed setup was used for the experiments. Carotid plaque samples excised at endarterectomy were subjected to uniaxial tensile, stress-relaxation, and cyclic loading protocols. Thirty percent of the underlying load level obtained from the uniaxial tensile test results was used to determine the change in mechanical properties of the tissue over time under a controlled testing environment (Control tests). The stress-relaxation test data was used to calibrate the hyperelastic (neo-Hookean, Ogden, Yeoh) and linear viscoelastic (Prony series) material parameters. The normalized relaxation force increased initially and slowly stabilized toward the end of relaxation phase, highlighting the viscoelastic behavior. During the cyclic tests, there was a decrease in the peak force as a function of the cycle number indicating mechanical distension due to repeated loading that varied with different frequencies. The material also accumulated residual deformation, which increased with the cycle number. This trend showed softening behavior of the samples. The results of this preliminary study provide an enhanced understanding of in vivo stress-relaxation and cyclic behavior of the human atherosclerotic plaque tissue.
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Affiliation(s)
- Phani Kumari Paritala
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Prasad K D V Yarlagadda
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Rhys Kansky
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Jiaqiu Wang
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Jessica Benitez Mendieta
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - YuanTong Gu
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Tim McGahan
- Department of Vascular Surgery, Princess Alexandra Hospital, Brisbane, QLD, Australia
| | - Thomas Lloyd
- Department of Radiology, Princess Alexandra Hospital, Brisbane, QLD, Australia
| | - Zhiyong Li
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD, Australia
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25
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Sherifova S, Holzapfel GA. Biomechanics of aortic wall failure with a focus on dissection and aneurysm: A review. Acta Biomater 2019; 99:1-17. [PMID: 31419563 PMCID: PMC6851434 DOI: 10.1016/j.actbio.2019.08.017] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/05/2019] [Accepted: 08/08/2019] [Indexed: 12/12/2022]
Abstract
Aortic dissections and aortic aneurysms are fatal events characterized by structural changes to the aortic wall. The maximum diameter criterion, typically used for aneurysm rupture risk estimations, has been challenged by more sophisticated biomechanically motivated models in the past. Although these models are very helpful for the clinicians in decision-making, they do not attempt to capture material failure. Following a short overview of the microstructure of the aorta, we analyze the failure mechanisms involved in the dissection and rupture by considering also traumatic rupture. We continue with a literature review of experimental studies relevant to quantify tissue strength. More specifically, we summarize more extensively uniaxial tensile, bulge inflation and peeling tests, and we also specify trouser, direct tension and in-plane shear tests. Finally we analyze biomechanically motivated models to predict rupture risk. Based on the findings of the reviewed studies and the rather large variations in tissue strength, we propose that an appropriate material failure criterion for aortic tissues should also reflect the microstructure in order to be effective. STATEMENT OF SIGNIFICANCE: Aortic dissections and aortic aneurysms are fatal events characterized by structural changes to the aortic wall. Despite the advances in medical, biomedical and biomechanical research, the mortality rates of aneurysms and dissections remain high. The present review article summarizes experimental studies that quantify the aortic wall strength and it discusses biomechanically motivated models to predict rupture risk. We identified contradictory observations and a large variation within and between data sets, which may be due to biological variations, different sample sizes, differences in experimental protocols, etc. Based on the findings of the reviewed literature and the rather large variations in tissue strength, it is proposed that an appropriate criterion for aortic failure should also reflect the microstructure.
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Affiliation(s)
- Selda Sherifova
- Institute of Biomechanics, Graz University of Technology, Stremayrgasse 16/2, 8010 Graz, Austria
| | - Gerhard A Holzapfel
- Institute of Biomechanics, Graz University of Technology, Stremayrgasse 16/2, 8010 Graz, Austria; Department of Structural Engineering, Norwegian Institute of Science and Technology (NTNU), 7491 Trondheim, Norway.
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26
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Yang CJ, Tsai SH, Wang JC, Chang WC, Lin CY, Tang ZC, Hsu HH. Association between acute aortic dissection and the distribution of aortic calcification. PLoS One 2019; 14:e0219461. [PMID: 31295298 PMCID: PMC6622544 DOI: 10.1371/journal.pone.0219461] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 06/21/2019] [Indexed: 11/19/2022] Open
Abstract
Objective Aortic calcification (AC) is associated with increased risks of cardiovascular events and mortality. Numerous studies have explored the association between calcification and abdominal artery aneurysm. However, evidence regarding the association between AC and acute aortic dissection (AAD) is limited. We aimed to evaluate the association between AC-related variables and the development of intimal tear (IT) in patients with AAD. Methods We conducted a retrospective observational study involving 64 patients with type A AAD and 32 patients with type B AAD from February, 2011 to January, 2017 at a tertiary referral medical center in Taiwan. We used the default analysis module “calcification score analysis” to calculate all the calcification variables, including AC scores and volume. Results We identified an association between AC and AAD. Patients with AAD had a greater AC volume in the aortic arch and greater AC scores for both the ascending aorta and the aortic arch than did patients without AAD. However, hypertension and coronary artery disease, rather than AC remained to be the independent risk factor for AAD in multivariate analysis. Patients with type A AAD had greater mean and cumulative AC volumes in the aortic arch, greater cumulative AC volumes in the whole aorta and higher cumulative AC scores in the aortic arch than did patients with type B AAD. ACs were superimposed on ITs in nearly half of the patients with AAD. In patients with type A AAD, AC was more commonly located distal to the IT and farther from the IT. Conclusions We identified the associations between AC-related variables and the location of IT in patients with AAD. However, AC was not an independent risk factor for AAD. The distribution of AC was different between patients with type A and type B AAD.
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Affiliation(s)
- Chih-Jen Yang
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Shih-Hung Tsai
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
- Department of Physiology and Biophysics, Graduate Institute of Physiology, National Defense Medical Center, Taipei, Taiwan
- * E-mail: (SHT); (HHH)
| | - Jen-Chun Wang
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Wei-Chou Chang
- Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chih-Yuan Lin
- Division of Cardiovascular surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Zun-Cheng Tang
- Department of Biological Imaging and Radiological Science, National Yang-Ming University, Taipei, Taiwan
| | - Hsian-He Hsu
- Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
- * E-mail: (SHT); (HHH)
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27
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Salman HE, Ramazanli B, Yavuz MM, Yalcin HC. Biomechanical Investigation of Disturbed Hemodynamics-Induced Tissue Degeneration in Abdominal Aortic Aneurysms Using Computational and Experimental Techniques. Front Bioeng Biotechnol 2019; 7:111. [PMID: 31214581 PMCID: PMC6555197 DOI: 10.3389/fbioe.2019.00111] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 05/02/2019] [Indexed: 11/13/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is the dilatation of the aorta beyond 50% of the normal vessel diameter. It is reported that 4-8% of men and 0.5-1% of women above 50 years of age bear an AAA and it accounts for ~15,000 deaths per year in the United States alone. If left untreated, AAA might gradually expand until rupture; the most catastrophic complication of the aneurysmal disease that is accompanied by a striking overall mortality of 80%. The precise mechanisms leading to AAA rupture remains unclear. Therefore, characterization of disturbed hemodynamics within AAAs will help to understand the mechanobiological development of the condition which will contribute to novel therapies for the condition. Due to geometrical complexities, it is challenging to directly quantify disturbed flows for AAAs clinically. Two other approaches for this investigation are computational modeling and experimental flow measurement. In computational modeling, the problem is first defined mathematically, and the solution is approximated with numerical techniques to get characteristics of flow. In experimental flow measurement, once the setup providing physiological flow pattern in a phantom geometry is constructed, velocity measurement system such as particle image velocimetry (PIV) enables characterization of the flow. We witness increasing number of applications of these complimentary approaches for AAA investigations in recent years. In this paper, we outline the details of computational modeling procedures and experimental settings and summarize important findings from recent studies, which will help researchers for AAA investigations and rupture mechanics.
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Affiliation(s)
| | - Burcu Ramazanli
- Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey
| | - Mehmet Metin Yavuz
- Department of Mechanical Engineering, Middle East Technical University, Ankara, Turkey
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28
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Petsophonsakul P, Furmanik M, Forsythe R, Dweck M, Schurink GW, Natour E, Reutelingsperger C, Jacobs M, Mees B, Schurgers L. Role of Vascular Smooth Muscle Cell Phenotypic Switching and Calcification in Aortic Aneurysm Formation. Arterioscler Thromb Vasc Biol 2019; 39:1351-1368. [PMID: 31144989 DOI: 10.1161/atvbaha.119.312787] [Citation(s) in RCA: 197] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Aortic aneurysm is a vascular disease whereby the ECM (extracellular matrix) of a blood vessel degenerates, leading to dilation and eventually vessel wall rupture. Recently, it was shown that calcification of the vessel wall is involved in both the initiation and progression of aneurysms. Changes in aortic wall structure that lead to aneurysm formation and vascular calcification are actively mediated by vascular smooth muscle cells. Vascular smooth muscle cells in a healthy vessel wall are termed contractile as they maintain vascular tone and remain quiescent. However, in pathological conditions they can dedifferentiate into a synthetic phenotype, whereby they secrete extracellular vesicles, proliferate, and migrate to repair injury. This process is called phenotypic switching and is often the first step in vascular pathology. Additionally, healthy vascular smooth muscle cells synthesize VKDPs (vitamin K-dependent proteins), which are involved in inhibition of vascular calcification. The metabolism of these proteins is known to be disrupted in vascular pathologies. In this review, we summarize the current literature on vascular smooth muscle cell phenotypic switching and vascular calcification in relation to aneurysm. Moreover, we address the role of vitamin K and VKDPs that are involved in vascular calcification and aneurysm. Visual Overview- An online visual overview is available for this article.
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Affiliation(s)
- Ploingarm Petsophonsakul
- From the Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands (P.P., M.F., C.R., L.S.)
| | - Malgorzata Furmanik
- From the Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands (P.P., M.F., C.R., L.S.)
| | - Rachael Forsythe
- Centre for Cardiovascular Science, University of Edinburgh, United Kingdom (R.F., M.D.)
| | - Marc Dweck
- Centre for Cardiovascular Science, University of Edinburgh, United Kingdom (R.F., M.D.)
| | - Geert Willem Schurink
- Department of Vascular Surgery (G.W.S., M.J., B.M.), Maastricht University Medical Center (MUMC), Maastricht, the Netherlands
| | - Ehsan Natour
- Department of Cardiovascular Surgery (E.N.), Maastricht University Medical Center (MUMC), Maastricht, the Netherlands.,European Vascular Center Aachen-Maastricht, Maastricht, the Netherlands (E.N., M.J., B.M.)
| | - Chris Reutelingsperger
- From the Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands (P.P., M.F., C.R., L.S.)
| | - Michael Jacobs
- Department of Vascular Surgery (G.W.S., M.J., B.M.), Maastricht University Medical Center (MUMC), Maastricht, the Netherlands.,European Vascular Center Aachen-Maastricht, Maastricht, the Netherlands (E.N., M.J., B.M.)
| | - Barend Mees
- Department of Vascular Surgery (G.W.S., M.J., B.M.), Maastricht University Medical Center (MUMC), Maastricht, the Netherlands.,European Vascular Center Aachen-Maastricht, Maastricht, the Netherlands (E.N., M.J., B.M.)
| | - Leon Schurgers
- From the Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands (P.P., M.F., C.R., L.S.)
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29
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Giannini C, Ladisa M, Lutz-Bueno V, Terzi A, Ramella M, Fusaro L, Altamura D, Siliqi D, Sibillano T, Diaz A, Boccafoschi F, Bunk O. X-ray scanning microscopies of microcalcifications in abdominal aortic and popliteal artery aneurysms. IUCRJ 2019; 6:267-276. [PMID: 30867924 PMCID: PMC6400185 DOI: 10.1107/s2052252519001544] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/28/2019] [Indexed: 05/27/2023]
Abstract
Abdominal aortic and popliteal artery aneurysms are vascular diseases which show massive degeneration, weakening of the vascular wall and loss of the vascular tissue functionality. They are driven by inflammatory, hemodynamical factors and biological alterations that may lead, in the case of an abdominal aortic aneurysm, to sudden and dangerous ruptures of the arteries. Here, human aortic and popliteal aneurysm tissues were obtained during surgical repair, and studied by synchrotron radiation X-ray scanning microdiffraction and small-angle scattering, to investigate the microcalcifications present in the tissues. Data collected during the experiments were transformed into quantitative microscopy images through the combination of statistical approaches and crystallographic methods. As a result of this multi-step analysis, microcalcifications, which are markers of the pathology, were classified in terms of chemical and structural content. This analysis helped to identify the presence of nanocrystalline hy-droxy-apatite and microcrystalline cholesterol, embedded in myofilament, and elastin-containing tissue with low collagen content in predominantly nanocrystalline areas. The generality of the approach allows it to be transferred to other types of tissue and other pathologies affected by microcalcifications, such as thyroid carcinoma, breast cancer, testicular microli-thia-sis or glioblastoma.
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Affiliation(s)
- C. Giannini
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - M. Ladisa
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - V. Lutz-Bueno
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5232, Switzerland
| | - A. Terzi
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - M. Ramella
- Department of Health Sciences, University of Piemonte Orientale, Via Solaroli 17, Novara, 28100, Italy
| | - L. Fusaro
- Department of Health Sciences, University of Piemonte Orientale, Via Solaroli 17, Novara, 28100, Italy
| | - D. Altamura
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - D. Siliqi
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - T. Sibillano
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
| | - A. Diaz
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5232, Switzerland
| | - F. Boccafoschi
- Institute of Crystallography, National Research Council, via Amendola 122/O, Bari, Bari 70125, Italy
- Department of Health Sciences, University of Piemonte Orientale, Via Solaroli 17, Novara, 28100, Italy
| | - O. Bunk
- Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, 5232, Switzerland
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30
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Abstract
The Abdominal Aortic Aneurysm (AAA) is a local dilation of the abdominal aorta and it is a cause for serious concern because of the high mortality associated with its rupture. Consequently, the understanding of the phenomena related to the creation and the progression of an AAA is of crucial importance. In this work, the complicated interaction between the blood flow and the AAA wall is numerically examined using a fully coupled Fluid-Structure Interaction (FSI) method. The study investigates the possible link between the dynamic behavior of an AAA and the blood viscosity variations attributed to the haematocrit value, while it also incorporates the pulsatile blood flow, the non-Newtonian behavior of blood and the hyperelasticity of the arterial wall. It was found that blood viscosity has no significant effect on von Mises stress magnitude and distribution, whereas there is a close relation between the haematocrit value and the Wall Shear Stress (WSS) magnitude in AAAs. This WSS variation can possibly alter the mechanical properties of the arterial wall and increase its growth rate or even its rupture possibility. The relationship between haematocrit and dynamic behavior of an AAA can be helpful in designing a patient specific treatment.
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31
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Rezvani-Sharif A, Tafazzoli-Shadpour M, Avolio A. Mechanical Characterization of the Lamellar Structure of Human Abdominal Aorta in the Development of Atherosclerosis: An Atomic Force Microscopy Study. Cardiovasc Eng Technol 2018; 10:181-192. [PMID: 30006817 DOI: 10.1007/s13239-018-0370-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/08/2018] [Indexed: 12/16/2022]
Abstract
Atherosclerosis is a major risk factor for cardiovascular disease. However, mechanisms of interaction of atherosclerotic plaque development and local stiffness of the lamellar structure of the arterial wall are not well established. In the current study, the local Young's modulus of the wall and plaque components were determined for three different groups of healthy, mildly diseased and advanced atherosclerotic human abdominal aortas. Histological staining was performed to highlight the atherosclerotic plaque components and lamellar structure of the aortic media, consisting of concentric layers of elastin and interlamellar zones. The force spectroscopy mode of the atomic force microscopy was utilized to determine Young's moduli of aortic wall lamellae and plaque components at the micron level. The high variability of Young's moduli (E) at different locations of the atherosclerotic plaque such as the fibrous cap (E = 15.5± 2.6 kPa), calcification zone (E = 103.7±19.5 kPa), and lipid pool (E = 3.5±1.2 kPa) were observed. Reduction of elastin lamellae stiffness (18.6%), as well as stiffening of interlamellar zones (50%), were detected in the diseased portion of the medial layer of abdominal aortic wall compared to the healthy artery. Additionally, significant differences in the stiffness of both elastin lamellae and interlamellar zones were observed between the diseased wall and disease-free wall in incomplete plaques. Our results elucidate the alternation of the stiffness of different lamellae in the human abdominal aortic wall with atherosclerotic plaque development and may provide new insight on the remodeling of the aortic wall during the progression of atherosclerosis.
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Affiliation(s)
- Alireza Rezvani-Sharif
- Faculty of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran.,Department of Biomedical Science, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | | | - Alberto Avolio
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
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32
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Farotto D, Segers P, Meuris B, Vander Sloten J, Famaey N. The role of biomechanics in aortic aneurysm management: requirements, open problems and future prospects. J Mech Behav Biomed Mater 2018; 77:295-307. [DOI: 10.1016/j.jmbbm.2017.08.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 08/09/2017] [Accepted: 08/15/2017] [Indexed: 12/18/2022]
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A Simple Blood Test, Such as Complete Blood Count, Can Predict Calcification Grade of Abdominal Aortic Aneurysm. Int J Vasc Med 2017; 2017:1370751. [PMID: 28948050 PMCID: PMC5602620 DOI: 10.1155/2017/1370751] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 07/16/2017] [Indexed: 01/04/2023] Open
Abstract
Objective The pathogenesis of abdominal aortic aneurysm (AAA) is complex and different factors, including calcification, are linked to increased complications. This study was conducted in order to verify if classical risk factors for AAA and cell blood count parameter could help in the identification of calcification progression of the aneurysm. Design Risk factors were collected and cell blood count was performed in patients with AAA and patients were analyzed for the presence of aorta calcification using CT angiography. Results We found no association of calcification grade with risk factors for AAA but we found a strong association between MCV, MCH, and calcification grade. Instead, no association was found with the other parameter that we analyzed. Conclusions In this study, we demonstrate that biomarkers such as MCV and MCH could have potential important information about AAA calcification progression and could be useful to discriminate between those patients that should undergo a rapid imaging, thus allowing prompt initiation of treatment of suspicious patients that do not need imaging repetition.
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Barrett HE, Cunnane EM, O Brien JM, Moloney MA, Kavanagh EG, Walsh MT. On the effect of computed tomography resolution to distinguish between abdominal aortic aneurysm wall tissue and calcification: A proof of concept. Eur J Radiol 2017; 95:370-377. [PMID: 28987694 DOI: 10.1016/j.ejrad.2017.08.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 08/16/2017] [Accepted: 08/22/2017] [Indexed: 12/15/2022]
Abstract
PURPOSE The purpose of this study is to determine the optimal target CT spatial resolution for accurately imaging abdominal aortic aneurysm (AAA) wall characteristics, distinguishing between tissue and calcification components, for an accurate assessment of rupture risk. MATERIALS AND METHODS Ruptured and non-ruptured AAA-wall samples were acquired from eight patients undergoing open surgical aneurysm repair upon institutional review board approval and informed consent was obtained from all patients. Physical measurements of AAA-wall cross-section were made using scanning electron microscopy. Samples were scanned using high resolution micro-CT scanning. A resolution range of 15.5-155μm was used to quantify the influence of decreasing resolution on wall area measurements, in terms of tissue and calcification. A statistical comparison between the reference resolution (15.5μm) and multi-detector CT resolution (744μm) was also made. RESULTS Electron microscopy examination of ruptured AAAs revealed extremely thin outer tissue structure <200μm in radial distribution which is supporting the aneurysm wall along with large areas of adjacent medial calcifications far greater in area than the tissue layer. The spatial resolution of 155μm is a significant predictor of the reference AAA-wall tissue and calcification area measurements (r=0.850; p<0.001; r=0.999; p<0.001 respectively). The tissue and calcification area at 155μm is correct within 8.8%±1.86 and 26.13%±9.40 respectively with sensitivity of 87.17% when compared to the reference. CONCLUSION The inclusion of AAA-wall measurements, through the use of high resolution-CT will elucidate the variations in AAA-wall tissue and calcification distributions across the wall which may help to leverage an improved assessment of AAA rupture risk.
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Affiliation(s)
- H E Barrett
- Centre for Applied Biomedical Engineering Research (CABER), Health Research Institute (HRI), School of Engineering, Bernal Institute, University of Limerick, Lonsdale Building, Limerick, Ireland
| | - E M Cunnane
- Centre for Applied Biomedical Engineering Research (CABER), Health Research Institute (HRI), School of Engineering, Bernal Institute, University of Limerick, Lonsdale Building, Limerick, Ireland
| | - J M O Brien
- Department of Radiology, University Hospital Limerick, Ireland
| | - M A Moloney
- Department of Vascular Surgery, University Hospital Limerick, Ireland
| | - E G Kavanagh
- Department of Vascular Surgery, University Hospital Limerick, Ireland
| | - M T Walsh
- Centre for Applied Biomedical Engineering Research (CABER), Health Research Institute (HRI), School of Engineering, Bernal Institute, University of Limerick, Lonsdale Building, Limerick, Ireland.
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35
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Conlisk N, Forsythe RO, Hollis L, Doyle BJ, McBride OMB, Robson JMJ, Wang C, Gray CD, Semple SIK, MacGillivray T, van Beek EJR, Newby DE, Hoskins PR. Exploring the Biological and Mechanical Properties of Abdominal Aortic Aneurysms Using USPIO MRI and Peak Tissue Stress: A Combined Clinical and Finite Element Study. J Cardiovasc Transl Res 2017; 10:489-498. [PMID: 28808955 PMCID: PMC5722953 DOI: 10.1007/s12265-017-9766-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 08/04/2017] [Indexed: 01/15/2023]
Abstract
Inflammation detected through the uptake of ultrasmall superparamagnetic particles of iron oxide (USPIO) on magnetic resonance imaging (MRI) and finite element (FE) modelling of tissue stress both hold potential in the assessment of abdominal aortic aneurysm (AAA) rupture risk. This study aimed to examine the spatial relationship between these two biomarkers. Patients (n = 50) > 40 years with AAA maximum diameters > = 40 mm underwent USPIO-enhanced MRI and computed tomography angiogram (CTA). USPIO uptake was compared with wall stress predictions from CTA-based patient-specific FE models of each aneurysm. Elevated stress was commonly observed in areas vulnerable to rupture (e.g. posterior wall and shoulder). Only 16% of aneurysms exhibited co-localisation of elevated stress and mural USPIO enhancement. Globally, no correlation was observed between stress and other measures of USPIO uptake (i.e. mean or peak). It is suggested that cellular inflammation and stress may represent different but complimentary aspects of AAA disease progression.
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Affiliation(s)
- Noel Conlisk
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK. .,School of Clinical Sciences, The University of Edinburgh, Edinburgh, UK. .,Institute for Bioengineering, The University of Edinburgh, Faraday Building, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JL, UK.
| | - Rachael O Forsythe
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,School of Clinical Sciences, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Lyam Hollis
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK
| | - Barry J Doyle
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, Perth, Australia.,School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
| | - Olivia M B McBride
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,School of Clinical Sciences, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Jennifer M J Robson
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,School of Clinical Sciences, The University of Edinburgh, Edinburgh, UK
| | - Chengjia Wang
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Calum D Gray
- Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Scott I K Semple
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Tom MacGillivray
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Centre for Clinical Brain Sciences, The University of Edinburgh, Edinburgh, UK
| | - Edwin J R van Beek
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - David E Newby
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, UK
| | - Peter R Hoskins
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK.,Institute for Bioengineering, The University of Edinburgh, Faraday Building, The King's Buildings, Mayfield Road, Edinburgh, EH9 3JL, UK
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36
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Ruiz de Galarreta S, Cazón A, Antón R, Finol EA. A Methodology for Verifying Abdominal Aortic Aneurysm Wall Stress. J Biomech Eng 2017; 139:2554137. [PMID: 27636678 DOI: 10.1115/1.4034710] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Indexed: 11/08/2022]
Abstract
An abdominal aortic aneurysm (AAA) is a permanent focal dilatation of the abdominal aorta of at least 1.5 times its normal diameter. Although the criterion of maximum diameter is still used in clinical practice to decide on a timely intervention, numerical studies have demonstrated the importance of other geometric factors. However, the major drawback of numerical studies is that they must be validated experimentally before clinical implementation. This work presents a new methodology to verify wall stress predicted from the numerical studies against the experimental testing. To this end, four AAA phantoms were manufactured using vacuum casting. The geometry of each phantom was subject to microcomputed tomography (μCT) scanning at zero and three other intraluminal pressures: 80, 100, and 120 mm Hg. A zero-pressure geometry algorithm was used to calculate the wall stress in the phantom, while the numerical wall stress was calculated with a finite-element analysis (FEA) solver based on the actual zero-pressure geometry subjected to 80, 100, and 120 mm Hg intraluminal pressure loading. Results demonstrate the moderate accuracy of this methodology with small relative differences in the average wall stress (1.14%). Additionally, the contribution of geometric factors to the wall stress distribution was statistically analyzed for the four phantoms. The results showed a significant correlation between wall thickness and mean curvature (MC) with wall stress.
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Affiliation(s)
- Sergio Ruiz de Galarreta
- Department of Mechanical Engineering, TECNUN, University of Navarra, Paseo Manuel de Lardizabal, 13, San Sebastián 20018, Spain e-mail:
| | - Aitor Cazón
- Department of Mechanical Engineering, TECNUN, University of Navarra, Paseo Manuel de Lardizabal, 13, San Sebastián 20018, Spain e-mail:
| | - Raúl Antón
- Department of Mechanical Engineering, TECNUN, University of Navarra, Paseo Manuel de Lardizabal, 13, San Sebastián 20018, Spain e-mail:
| | - Ender A Finol
- Department of Biomedical Engineering, The University of Texas at San Antonio, One UTSA Circle, AET 1.360, San Antonio, TX 78249-0669 e-mail:
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37
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Garrafa E, Giacomelli A, Ravanelli M, Dell'Era P, Peroni M, Zanotti C, Caimi L, Bonardelli S. Prediction of abdominal aortic aneurysm calcification by means of variation of high-sensitivity C-reactive protein. JRSM Cardiovasc Dis 2016; 5:2048004016682177. [PMID: 27994851 PMCID: PMC5153147 DOI: 10.1177/2048004016682177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/03/2016] [Accepted: 11/02/2016] [Indexed: 12/23/2022] Open
Abstract
Objective Abdominal aortic aneurysms are a major cause of death in developed countries, and thrombus and calcification of the aneurysm have been linked to increased complications. This study was conducted in order to identify the biochemical marker associated to the presence of intraluminal thrombus or calcification progression of the aneurysm. Design Several clinical laboratory parameters were measured in patients with abdominal aortic aneurysms, in particular those already demonstrated to be related to the pathology, such as lipoprotein (a), white blood cell count, fibrinogen and high-sensitivity C-reactive protein. Most of the patients were analysed for the presence of thrombus or aorta calcification using CT angiography. Results Unlike previous findings, we found no association between intraluminal thrombus formation and lipoprotein (a), but we evidenced that patients with lower grade of calcification tend to have higher plasma high-sensitivity C-reactive protein values compared with patients with a higher degree of calcification. Instead, no association was found with either white blood cell count or fibrinogen level. Conclusions This study suggests that high-sensitivity C-reactive protein is a useful biomarker to assess the evolution of calcification and could be used in triaging patients to identify those who should undergo a rapid imaging, thus allowing prompt initiation of treatment or rule-out suspicious patients from non-essential imaging repetition.
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Affiliation(s)
- Emirena Garrafa
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Alessio Giacomelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Marco Ravanelli
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Patrizia Dell'Era
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Michele Peroni
- Department of Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
| | - Camilla Zanotti
- Department of Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
| | - Luigi Caimi
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Stefano Bonardelli
- Department of Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
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38
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Cheheltani R, Pichamuthu JE, Rao J, Weinbaum JS, Kiani MF, Vorp DA, Pleshko N. Fourier Transform Infrared Spectroscopic Imaging-Derived Collagen Content and Maturity Correlates with Stress in the Aortic Wall of Abdominal Aortic Aneurysm Patients. Cardiovasc Eng Technol 2016; 8:70-80. [PMID: 27995569 DOI: 10.1007/s13239-016-0289-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 12/04/2016] [Indexed: 01/22/2023]
Abstract
Abdominal aortic aneurysm (AAA) is a degenerative disease of the aorta characterized by severe disruption of the structural integrity of the aortic wall and its major molecular constituents. From the early stages of disease, elastin in the aorta becomes highly degraded and is replaced by collagen. Questions persist as to the contribution of collagen content, quality and maturity to the potential for rupture. Here, using our recently developed Fourier transform infrared imaging spectroscopy (FT-IRIS) method, we quantified collagen content and maturity in the wall of AAA tissues in pairs of specimens with different wall stresses. CT scans of AAAs from 12 patients were used to create finite element models to estimate stress in different regions of tissue. Each patient underwent elective repair of the AAA, and two segments of the AAA tissues from anatomic regions more proximal or distal with different wall stresses were evaluated by histology and FT-IRIS after excision. For each patient, collagen content was generally greater in the tissue location with lower wall stress, which corresponded to the more distal anatomic regions. The wall stress/collagen ratio was greater in the higher stress region compared to the lower stress region (1.01 ± 1.09 vs. 0.55 ± 0.084, p = 0.02). The higher stress region also corresponded to the location with reduced intraluminal thrombus thickness. Further, collagen maturity tended to decrease with increased collagen content (p = 0.068, R = 0.38). Together, these results suggest that an increase in less mature collagen content in AAA patients does not effectively compensate for the loss of elastin in the aortic wall, and results in a reduced capability to endure wall stresses.
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Affiliation(s)
- Rabee Cheheltani
- Department of Mechanical Engineering, Temple University, Philadelphia, PA, USA.,Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Jayashree Rao
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Justin S Weinbaum
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mohammad F Kiani
- Department of Mechanical Engineering, Temple University, Philadelphia, PA, USA
| | - David A Vorp
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Surgery, Department of Cardiothoracic Surgery, and Center for Vascular Remodeling and Regeneration, University of Pittsburgh, Pittsburgh, PA, USA
| | - Nancy Pleshko
- Department of Bioengineering, Temple University, Philadelphia, PA, USA.
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39
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Cross-Sectional Imaging to Evaluate the Risk of Rupture in Abdominal Aortic Aneurysms: Review article based on a dissertation submitted to fulfill the academic grade of doctor in medical sciences (….), entitled: Imaging the mechanisms involved in abdominal aortic aneurysms rupture; a step towards patient-specific risk assessment. J Belg Soc Radiol 2016; 100:91. [PMID: 30151486 PMCID: PMC6100636 DOI: 10.5334/jbr-btr.1204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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40
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Cunnane EM, Mulvihill JJE, Barrett HE, Hennessy MM, Kavanagh EG, Walsh MT. Mechanical properties and composition of carotid and femoral atherosclerotic plaques: A comparative study. J Biomech 2016; 49:3697-3704. [PMID: 27776741 DOI: 10.1016/j.jbiomech.2016.09.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 09/27/2016] [Accepted: 09/30/2016] [Indexed: 01/25/2023]
Abstract
This study compares the mechanical properties of excised carotid and femoral human plaques and also develops a predictor of these properties based on plaque composition. Circumferential planar tension tests were performed on 24 carotid and 16 femoral plaque samples. Composition was characterised using Fourier Transform Infrared spectroscopy. Stretch at failure, strength, and stiffness are significantly higher in the carotid group (P=.012, P<.001 and P=.002, respectively). The ratio of calcified to lipid plaque content demonstrates the strongest correlation with the stretch at failure and strength (R2=.285, P<.001 and R2=.347, P<.001). No composition based parameter correlates significantly with stiffness. The significantly different mechanical properties of the two groups aids in explaining the varying endovascular treatment outcomes clinically observed in these vessels. Furthermore, determining the ratio of calcified to lipid plaque content may be useful in predicting individual plaque mechanical response to endovascular treatment.
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Affiliation(s)
- Eoghan M Cunnane
- School of Engineering, Bernal Institute, and the Health Research Institute, University of Limerick, Ireland
| | - John J E Mulvihill
- School of Engineering, Bernal Institute, and the Health Research Institute, University of Limerick, Ireland
| | - Hilary E Barrett
- School of Engineering, Bernal Institute, and the Health Research Institute, University of Limerick, Ireland
| | - Mairead M Hennessy
- Department of Vascular Surgery, University Hospital Limerick, Limerick, Ireland
| | - Eamon G Kavanagh
- Department of Vascular Surgery, University Hospital Limerick, Limerick, Ireland
| | - Michael T Walsh
- School of Engineering, Bernal Institute, and the Health Research Institute, University of Limerick, Ireland.
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41
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Polzer S, Gasser TC. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index. J R Soc Interface 2016; 12:20150852. [PMID: 26631334 DOI: 10.1098/rsif.2015.0852] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach.
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Affiliation(s)
- Stanislav Polzer
- Institute of Solid Mechanics, Mechatronics and Biomechanics, Brno University of Technology, Brno, Czech Republic
| | - T Christian Gasser
- KTH Solid Mechanics, School of Engineering Sciences, KTH Royal Institute of Technology, Stockholm, Sweden
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42
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Nosoudi N, Chowdhury A, Siclari S, Karamched S, Parasaram V, Parrish J, Gerard P, Vyavahare N. Reversal of Vascular Calcification and Aneurysms in a Rat Model Using Dual Targeted Therapy with EDTA- and PGG-Loaded Nanoparticles. Am J Cancer Res 2016; 6:1975-1987. [PMID: 27698934 PMCID: PMC5039337 DOI: 10.7150/thno.16547] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 07/28/2016] [Indexed: 02/06/2023] Open
Abstract
Degeneration of elastic lamina and vascular calcification are common features of vascular pathology such as aortic aneurysms. We tested whether dual therapy with targeted nanoparticles (NPs) can remove mineral deposits (by delivery of a chelating agent, ethylene diamine tetraacetic acid (EDTA)) and restore elastic lamina (by delivery of a polyphenol, pentagalloyl glucose (PGG)) to reverse moderate aneurysm development. EDTA followed by PGG NP delivery led to reduction in macrophage recruitment, matrix metalloproteinase (MMP) activity, elastin degradation and calcification in the aorta as compared to delivery of control blank NPs. Such dual therapy restored vascular elastic lamina and improved vascular function as observed by improvement in circumferential strain. Therefore, dual targeted therapy may be an attractive option to remove mineral deposits and restore healthy arterial structures in moderately developed aneurysms.
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43
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Hybrid Treatment of an Abdominal Aortic Aneurysm with Severe Calcification of the Neck and Aortic Bifurcation. Ann Vasc Surg 2016; 36:294.e7-294.e11. [PMID: 27423723 DOI: 10.1016/j.avsg.2016.03.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/20/2016] [Accepted: 03/21/2016] [Indexed: 11/22/2022]
Abstract
BACKGROUND Severe calcification of the aorta or iliac vessels remains a major concern when planning open or endovascular treatment of an abdominal aortic aneurysm (AAA). Therefore, we present a unique case of an AAA with concomitant severe calcification of the entire infrarenal aortoiliac region and discuss on proper management. CASE REPORT A 70-year-old patient with a symptomatic AAA was scheduled for repair. The diagnostic investigation revealed a 70-mm-diameter AAA with severe calcification of the neck and the iliac and femoral arteries, raising major concerns regarding the proper repair strategy. Under careful consideration of all the risks and parameters, the patient underwent a hybrid treatment with endovascular balloon occlusion of the aortic neck and careful clamping just proximal to the bifurcation. Minimal mobilization of the aorta, careful transecting and drilling of the aortic wall, and careful suturing of a straight graft were part of the whole strategy. One-year follow-up of the patient is unremarkable. CONCLUSIONS In cases of AAA with significantly calcified aorta and aortic bifurcation, careful preoperative planning is imperative, taking into consideration the individualized characteristics of each patient. Hybrid techniques including proximal endovascular occlusion, careful mobilizations, aortic wall drilling, and tight suturing of the graft could be a reasonable strategy for such patients. However, larger case series is needed to prove the efficacy of this method.
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44
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Conlisk N, Geers AJ, McBride OMB, Newby DE, Hoskins PR. Patient-specific modelling of abdominal aortic aneurysms: The influence of wall thickness on predicted clinical outcomes. Med Eng Phys 2016; 38:526-37. [PMID: 27056256 DOI: 10.1016/j.medengphy.2016.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 01/04/2016] [Accepted: 03/06/2016] [Indexed: 10/22/2022]
Abstract
Rupture of abdominal aortic aneurysms (AAAs) is linked to aneurysm morphology. This study investigates the influence of patient-specific (PS) AAA wall thickness on predicted clinical outcomes. Eight patients under surveillance for AAAs were selected from the MA(3)RS clinical trial based on the complete absence of intraluminal thrombus. Two finite element (FE) models per patient were constructed; the first incorporated variable wall thickness from CT (PS_wall), and the second employed a 1.9mm uniform wall (Uni_wall). Mean PS wall thickness across all patients was 1.77±0.42mm. Peak wall stress (PWS) for PS_wall and Uni_wall models was 0.6761±0.3406N/mm(2) and 0.4905±0.0850N/mm(2), respectively. In 4 out of 8 patients the Uni_wall underestimated stress by as much as 55%; in the remaining cases it overestimated stress by up to 40%. Rupture risk more than doubled in 3 out of 8 patients when PS_wall was considered. Wall thickness influenced the location and magnitude of PWS as well as its correlation with curvature. Furthermore, the volume of the AAA under elevated stress increased significantly in AAAs with higher rupture risk indices. This highlights the sensitivity of standard rupture risk markers to the specific wall thickness strategy employed.
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Affiliation(s)
- Noel Conlisk
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, EH16 4TJ, UK; Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, EH16 4TJ, UK.
| | - Arjan J Geers
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | - Olivia M B McBride
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | - David E Newby
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, EH16 4TJ, UK; Clinical Research Imaging Centre, The University of Edinburgh, Edinburgh, EH16 4TJ, UK
| | - Peter R Hoskins
- Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, EH16 4TJ, UK
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45
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Gasser TC. Biomechanical Rupture Risk Assessment: A Consistent and Objective Decision-Making Tool for Abdominal Aortic Aneurysm Patients. AORTA : OFFICIAL JOURNAL OF THE AORTIC INSTITUTE AT YALE-NEW HAVEN HOSPITAL 2016; 4:42-60. [PMID: 27757402 DOI: 10.12945/j.aorta.2015.15.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/04/2016] [Indexed: 12/20/2022]
Abstract
Abdominal aortic aneurysm (AAA) rupture is a local event in the aneurysm wall that naturally demands tools to assess the risk for local wall rupture. Consequently, global parameters like the maximum diameter and its expansion over time can only give very rough risk indications; therefore, they frequently fail to predict individual risk for AAA rupture. In contrast, the Biomechanical Rupture Risk Assessment (BRRA) method investigates the wall's risk for local rupture by quantitatively integrating many known AAA rupture risk factors like female sex, large relative expansion, intraluminal thrombus-related wall weakening, and high blood pressure. The BRRA method is almost 20 years old and has progressed considerably in recent years, it can now potentially enrich the diameter indication for AAA repair. The present paper reviews the current state of the BRRA method by summarizing its key underlying concepts (i.e., geometry modeling, biomechanical simulation, and result interpretation). Specifically, the validity of the underlying model assumptions is critically disused in relation to the intended simulation objective (i.e., a clinical AAA rupture risk assessment). Next, reported clinical BRRA validation studies are summarized, and their clinical relevance is reviewed. The BRRA method is a generic, biomechanics-based approach that provides several interfaces to incorporate information from different research disciplines. As an example, the final section of this review suggests integrating growth aspects to (potentially) further improve BRRA sensitivity and specificity. Despite the fact that no prospective validation studies are reported, a significant and still growing body of validation evidence suggests integrating the BRRA method into the clinical decision-making process (i.e., enriching diameter-based decision-making in AAA patient treatment).
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Affiliation(s)
- T Christian Gasser
- KTH Royal Institute of Technology, KTH Solid Mechanics, Stockholm, Sweden
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Schmitz-Rixen T, Keese M, Hakimi M, Peters A, Böckler D, Nelson K, Grundmann RT. Ruptured abdominal aortic aneurysm—epidemiology, predisposing factors, and biology. Langenbecks Arch Surg 2016; 401:275-88. [DOI: 10.1007/s00423-016-1401-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 03/04/2016] [Indexed: 12/19/2022]
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Doyle BJ, Miller K, Newby DE, Hoskins PR. Commentary: Computational Biomechanics–Based Rupture Prediction of Abdominal Aortic Aneurysms. J Endovasc Ther 2016; 23:121-4. [DOI: 10.1177/1526602815615821] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Barry J. Doyle
- Vascular Engineering, Intelligent Systems for Medicine Laboratory, School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Scotland, UK
| | - Karol Miller
- Vascular Engineering, Intelligent Systems for Medicine Laboratory, School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
- Institute of Mechanics and Advanced Materials, Cardiff University, Cardiff, Wales, UK
| | - David E. Newby
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Scotland, UK
- Clinical Research Imaging Centre, University of Edinburgh, Scotland, UK
| | - Peter R. Hoskins
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Scotland, UK
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Volokh KY, Aboudi J. Aneurysm strength can decrease under calcification. J Mech Behav Biomed Mater 2015; 57:164-74. [PMID: 26717251 DOI: 10.1016/j.jmbbm.2015.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/04/2015] [Accepted: 11/11/2015] [Indexed: 12/18/2022]
Abstract
Aneurysms are abnormal dilatations of vessels in the vascular system that are prone to rupture. Prediction of the aneurysm rupture is a challenging and unsolved problem. Various factors can lead to the aneurysm rupture and, in the present study, we examine the effect of calcification on the aneurysm strength by using micromechanical modeling. The calcified tissue is considered as a composite material in which hard calcium particles are embedded in a hyperelastic soft matrix. Three experimentally calibrated constitutive models incorporating a failure description are used for the matrix representation. Two constitutive models describe the aneurysmal arterial wall and the third one - the intraluminal thrombus. The stiffness and strength of the calcified tissue are simulated in uniaxial tension under the varying amount of calcification, i.e. the relative volume of the hard inclusion within the periodic unit cell. In addition, the triaxiality of the stress state, which can be a trigger for the cavitation instability, is tracked. Results of the micromechanical simulation show an increase of the stiffness and a possible decrease of the strength of the calcified tissue as compared to the non-calcified one. The obtained results suggest that calcification (i.e. the presence of hard particles) can significantly affect the stiffness and strength of soft tissue. The development of refined experimental techniques that will allow for the accurate quantitative assessment of calcification is desirable.
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Affiliation(s)
| | - Jacob Aboudi
- Faculty of Engineering, Tel Aviv University, Israel.
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Hendy K, Gunnarsson R, Cronin O, Golledge J. Infra-renal abdominal aortic calcification volume does not predict small abdominal aortic aneurysm growth. Atherosclerosis 2015; 243:334-8. [DOI: 10.1016/j.atherosclerosis.2015.07.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 07/10/2015] [Accepted: 07/14/2015] [Indexed: 01/16/2023]
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50
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Sassani SG, Kakisis J, Tsangaris S, Sokolis DP. Layer-dependent wall properties of abdominal aortic aneurysms: Experimental study and material characterization. J Mech Behav Biomed Mater 2015; 49:141-61. [DOI: 10.1016/j.jmbbm.2015.04.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/21/2015] [Accepted: 04/27/2015] [Indexed: 12/11/2022]
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