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Shlimon K, Lindenberger M, De Basso R, Cinthio M, Bjarnegård N. Increased diameter and stiffness of elastic but not muscular arteries in men with abdominal aortic aneurysm. J Appl Physiol (1985) 2024; 136:1410-1417. [PMID: 38660725 DOI: 10.1152/japplphysiol.00875.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 04/05/2024] [Accepted: 04/20/2024] [Indexed: 04/26/2024] Open
Abstract
It has been proposed that formation of abdominal aortic aneurysm (AAA) is part of a systemic arterial dilatative disease. However, arteries in the upper extremities are scarcely studied and it remains unclear whether both muscular and elastic arteries are affected by the proposed systemic arterial dilatation. The aim of this study was to investigate the diameter and stiffness of muscular and elastic arteries in arterial branches originating from the aortic arch. Twenty-six men with AAA (69 ± 4 yr) and 57 men without AAA (70 ± 5 yr) were included in the study. Ultrasound was used to examine the distal and proximal brachial artery, axillary artery, and common carotid artery (CCA), and measurement of diameter and diameter change was performed with wall-tracking software. Blood pressure measurements were used to calculate local arterial wall stiffness indices. The AAA cohort presented larger arterial diameters in the CCA and axillary artery after adjustment for body surface area (P = 0.002, respectively), whereas the brachial artery diameters were unchanged. Indices of increased stiffness in CCA (e.g., lower distensibility, P = 0.003) were seen in subjects with AAA after adjustments for body mass index and mean arterial blood pressure. This study supports the theory of a systemic arterial dilating diathesis in peripheral elastic, but not in muscular, arteries. Peripheral elastic arteries also exhibited increased stiffness, in analogy with findings in the aorta in AAA.NEW & NOTEWORTHY We present data partially supporting the notion of abdominal aortic aneurysm being a systemic vascular disease with focal manifestation in the abdominal aorta, from two well-defined groups recruited from a regional screening program. We show that elastic arteries distal from the aorta exhibit vascular alterations without aneurysmal formation in subjects with AAA compared with controls while muscular arteries seem unaffected.
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Affiliation(s)
- Kristian Shlimon
- Division of Diagnostics and Specialist Medicine, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Marcus Lindenberger
- Division of Diagnostics and Specialist Medicine, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
- Department of Cardiology, Linköping University, Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Rachel De Basso
- Department of Natural Sciences and Biomedicine, School of Health and Welfare, Jönköping University, Jönköping, Sweden
| | - Magnus Cinthio
- Department of Electrical Measurements, Lund University, Lund, Sweden
| | - Niclas Bjarnegård
- Division of Diagnostics and Specialist Medicine, Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
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Puertas-Umbert L, Almendra-Pegueros R, Jiménez-Altayó F, Sirvent M, Galán M, Martínez-González J, Rodríguez C. Novel pharmacological approaches in abdominal aortic aneurysm. Clin Sci (Lond) 2023; 137:1167-1194. [PMID: 37559446 PMCID: PMC10415166 DOI: 10.1042/cs20220795] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/05/2023] [Accepted: 07/28/2023] [Indexed: 08/11/2023]
Abstract
Abdominal aortic aneurysm (AAA) is a severe vascular disease and a major public health issue with an unmet medical need for therapy. This disease is featured by a progressive dilation of the abdominal aorta, boosted by atherosclerosis, ageing, and smoking as major risk factors. Aneurysm growth increases the risk of aortic rupture, a life-threatening emergency with high mortality rates. Despite the increasing progress in our knowledge about the etiopathology of AAA, an effective pharmacological treatment against this disorder remains elusive and surgical repair is still the unique available therapeutic approach for high-risk patients. Meanwhile, there is no medical alternative for patients with small aneurysms but close surveillance. Clinical trials assessing the efficacy of antihypertensive agents, statins, doxycycline, or anti-platelet drugs, among others, failed to demonstrate a clear benefit limiting AAA growth, while data from ongoing clinical trials addressing the benefit of metformin on aneurysm progression are eagerly awaited. Recent preclinical studies have postulated new therapeutic targets and pharmacological strategies paving the way for the implementation of future clinical studies exploring these novel therapeutic strategies. This review summarises some of the most relevant clinical and preclinical studies in search of new therapeutic approaches for AAA.
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Affiliation(s)
- Lídia Puertas-Umbert
- Institut d’Investigació Biomèdica Sant Pau (IIB SANT PAU), Barcelona, Spain
- CIBER de Enfermedades Cardiovasculares, ISCIII, Madrid, Spain
| | | | - Francesc Jiménez-Altayó
- Department of Pharmacology, Therapeutics and Toxicology, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
- Neuroscience Institute, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marc Sirvent
- CIBER de Enfermedades Cardiovasculares, ISCIII, Madrid, Spain
- Departamento de Angiología y Cirugía Vascular del Hospital Universitari General de Granollers, Granollers, Barcelona, Spain
| | - María Galán
- Institut d’Investigació Biomèdica Sant Pau (IIB SANT PAU), Barcelona, Spain
- CIBER de Enfermedades Cardiovasculares, ISCIII, Madrid, Spain
- Departamento de Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - José Martínez-González
- Institut d’Investigació Biomèdica Sant Pau (IIB SANT PAU), Barcelona, Spain
- CIBER de Enfermedades Cardiovasculares, ISCIII, Madrid, Spain
- Instituto de Investigaciones Biomédicas de Barcelona (IIBB-CSIC), Barcelona, Spain
| | - Cristina Rodríguez
- Institut d’Investigació Biomèdica Sant Pau (IIB SANT PAU), Barcelona, Spain
- CIBER de Enfermedades Cardiovasculares, ISCIII, Madrid, Spain
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Clifford K, Majumder A, Hill B, Young-Gough A, Jones GT, Krysa J. The Impact of Suprarenal Diameter on Outcomes Following Endovascular Aneurysm Repair: A Retrospective Cohort Study. Vasc Endovascular Surg 2022; 56:15385744221108052. [PMID: 35680567 DOI: 10.1177/15385744221108052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES To determine the association between suprarenal aortic diameters and complications that may be attributed to a dilating phenotype following endovascular abdominal aortic aneurysm repair. DESIGN This study is a retrospective review. METHODS We measured the abdominal aortas of 147 consecutive patients with a mean age of 78.5 (range 60-93) years, who had a mean Endovascular aneurysm repair (EVAR) follow-up of 3 years (6 months to 8 years) at a public Hospital. Aortic calibres measured 5 mm above the highest renal artery were recorded, patients were categorised according to suprarenal diameter; Group A: greater than 25 mm, Group B: less than or equal to 25 mm. Stent migration, aneurysmal sac growth, presence of an endoleak and its type, occlusion events, rupture, interventions and mortality, as well as clinical history and demographic data were compared between groups. RESULTS There was a significantly higher occurrence of stent migration (11% v 0%; P = .01) in patients with larger suprarenal aortas (Group A). The occurrence of any endoleak did not differ between the groups, however, significantly more complications resulting in secondary intervention, excluding occlusions, were noted in Group A (34% vs 17%, P = .04). CONCLUSIONS The results from this study suggest that patients with above-average suprarenal diameters (categorised as dilators) may have a higher occurrence of specific complications following EVAR. A more detailed study to establish the association of suprarenal calibre with types of complications following EVAR is warranted.
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Affiliation(s)
- Kari Clifford
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Arunesh Majumder
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Brigid Hill
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Anastasia Young-Gough
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Gregory T Jones
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Jolanta Krysa
- Department of Surgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
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Vermeulen JJ, Jansen AJS, van de Sande S, Hartman YA, Holewijn S, Reijnen MM, Thijssen DH. Carotid artery vasoreactivity correlates with abdominal aortic vasoreactivity in young healthy individuals but not in patients with abdominal aortic aneurysm. Curr Res Physiol 2022; 5:224-231. [PMID: 35677214 PMCID: PMC9168379 DOI: 10.1016/j.crphys.2022.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/17/2022] Open
Abstract
Background Sympathetic stimulation of central arteries, such as coronary and carotid arteries, cause vasodilation in healthy subjects, but vasoconstriction in those with increased cardiovascular risk. This study compared vasoreactivity to sympathetic stimulation between abdominal aorta and carotid artery in healthy young individuals (young group, n = 20), in patients with abdominal aortic aneurysm (AAA group, n = 20) and in a healthy older group, age- and gender matched with AAA group (matched group, n = 18). Method All subjects underwent cold pressor test, while performing concomitantly duplex ultrasound of abdominal aorta and carotid artery vasoreactivity. Observer-independent software was used to analyze and calculate magnitude and timing of maximum vasodilation or vasoconstriction. Pearson's correlation coefficient was calculated to investigate vasoreactivity between arteries. Results Carotid artery reactivity [Interquartile range 25%, Interquartile range 75%] did not significantly differ between the young, matched and AAA group (3.5% [1.4, 4.7], 2.6% [2.0, 4.1] and 2.2% [-1.9, 3.7], respectively, p = 0.301). Abdominal aortic responsiveness demonstrated larger differences between young (4.9% [-0.2, 8.4]), matched (3.3% [-2.5, 4.4]) and individuals with AAA (0.5% [-3.9, 4.1], p = 0.059). Pooled analysis showed a significant correlation between carotid and abdominal aortic vasoreactivity (r = 0.444, p = 0.001). Subgroup analyses demonstrated significant correlation between both arteries in young (r = 0.636, p = 0.003), but not matched (r = −0.040, p = 0.866) or AAA group (r = 0.410, p = 0.129). Conclusions Sympathetic stimulation induces powerful vasodilation of the carotid artery and abdominal aorta, which is significantly correlated in healthy individuals. No such correlation is present in abdominal aortic aneurysm patients. This suggests the aneurysm alters local abdominal aorta vasoreactivity, but not the carotid artery. Vasoreactivity is significantly correlated between carotid and abdominal aorta. Presence of abdominal aneurysm was associated with local impaired vasoreactivity. Abdominal aorta demonstrates a stronger vasoreactivity than the carotid artery. Vasoreactivity of the carotid artery did not differ between groups.
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Radial artery lumen diameter and intima thickness in patients with abdominal aortic aneurysm. JVS Vasc Sci 2022; 3:274-284. [PMID: 36052216 PMCID: PMC9424594 DOI: 10.1016/j.jvssci.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/22/2022] [Indexed: 11/21/2022] Open
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Martínez-González J, Varona S, Cañes L, Galán M, Briones AM, Cachofeiro V, Rodríguez C. Emerging Roles of Lysyl Oxidases in the Cardiovascular System: New Concepts and Therapeutic Challenges. Biomolecules 2019; 9:biom9100610. [PMID: 31615160 PMCID: PMC6843517 DOI: 10.3390/biom9100610] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 12/13/2022] Open
Abstract
Lysyl oxidases (LOX and LOX-likes (LOXLs) isoenzymes) belong to a family of copper-dependent enzymes classically involved in the covalent cross-linking of collagen and elastin, a pivotal process that ensures extracellular matrix (ECM) stability and provides the tensile and elastic characteristics of connective tissues. Besides this structural role, in the last years, novel biological properties have been attributed to these enzymes, which can critically influence cardiovascular function. LOX and LOXLs control cell proliferation, migration, adhesion, differentiation, oxidative stress, and transcriptional regulation and, thereby, their dysregulation has been linked to a myriad of cardiovascular pathologies. Lysyl oxidase could modulate virtually all stages of the atherosclerotic process, from endothelial dysfunction and plaque progression to calcification and rupture of advanced and complicated plaques, and contributes to vascular stiffness in hypertension. The alteration of LOX/LOXLs expression underlies the development of other vascular pathologies characterized by a destructive remodeling of the ECM, such as aneurysm and artery dissections, and contributes to the adverse myocardial remodeling and dysfunction in hypertension, myocardial infarction, and obesity. This review examines the most recent advances in the study of LOX and LOXLs biology and their pathophysiological role in cardiovascular diseases with special emphasis on their potential as therapeutic targets.
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Affiliation(s)
- José Martínez-González
- Instituto de Investigaciones Biomédicas de Barcelona (IIBB-CSIC), 08036 Barcelona, Spain.
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Instituto de Investigación Biomédica Sant Pau (IIB-Sant Pau), 08041 Barcelona, Spain.
| | - Saray Varona
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Instituto de Investigación Biomédica Sant Pau (IIB-Sant Pau), 08041 Barcelona, Spain.
| | - Laia Cañes
- Instituto de Investigaciones Biomédicas de Barcelona (IIBB-CSIC), 08036 Barcelona, Spain.
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Instituto de Investigación Biomédica Sant Pau (IIB-Sant Pau), 08041 Barcelona, Spain.
| | - María Galán
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Instituto de Investigación Biomédica Sant Pau (IIB-Sant Pau), 08041 Barcelona, Spain.
- Institut de Recerca Hospital de la Santa Creu i Sant Pau-Programa ICCC, 08025 Barcelona, Spain.
| | - Ana M Briones
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Departmento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Instituto de Investigación Hospital La Paz, 28029 Madrid, Spain.
| | - Victoria Cachofeiro
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid-Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), 28040 Madrid, Spain.
| | - Cristina Rodríguez
- CIBER de Enfermedades Cardiovasculares, Instituto de Salud Carlos III, 28029 Madrid, Spain.
- Instituto de Investigación Biomédica Sant Pau (IIB-Sant Pau), 08041 Barcelona, Spain.
- Institut de Recerca Hospital de la Santa Creu i Sant Pau-Programa ICCC, 08025 Barcelona, Spain.
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7
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Yao L, Folsom AR, Alonso A, Lutsey PL, Pankow JS, Guan W, Cheng S, Lederle FA, Tang W. Association of carotid atherosclerosis and stiffness with abdominal aortic aneurysm: The atherosclerosis risk in communities (ARIC) study. Atherosclerosis 2018; 270:110-116. [PMID: 29407878 PMCID: PMC5844275 DOI: 10.1016/j.atherosclerosis.2018.01.044] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 01/20/2018] [Accepted: 01/24/2018] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND AIMS Individuals with atherosclerosis and stiffness often have increased abdominal aortic diameters, but prospective evidence linking them to the risk of abdominal aortic aneurysm (AAA) is limited. METHODS We prospectively examined the relationship of carotid atherosclerosis and stiffness with future risk of AAA in ARIC. At Visits 1 (1987-89) or 2 (1990-1992), we assessed carotid atherosclerosis (represented by greater carotid intima-media thickness [cIMT] or presence of atherosclerotic plaque) and lower carotid distensibility (reflected by a higher carotid Beta Index). We identified incident, clinical AAAs during follow-up through 2011 using hospital discharge codes, Medicare outpatient diagnoses, or death certificates. RESULTS Participants' mean age at baseline was 54.2 years (SD 5.8), 45% were male and 73% white. During a median of 22.5 years of follow-up, 542 clinical AAAs were ascertained. After multivariable adjustment, the presence of carotid atherosclerotic plaque at baseline was associated with 1.31 (95% CI: 1.10-1.57; p = 0.003) times higher risk of clinical AAA. Greater cIMT and Beta Index were also associated with clinical AAA with a dose-response across quartiles (p trend for both: 0.006; hazard ratios [95% CI] for the highest vs. lowest quartiles: 1.55 [1.13-2.11] and 1.68 [1.16-2.43], respectively). The associations of cIMT and Beta Index with AAA were independent of each other. CONCLUSIONS This prospective population-based study found that indices of greater carotid atherosclerosis and lower carotid distensibility are markers of increased AAA risk.
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Affiliation(s)
- Lu Yao
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - Aaron R Folsom
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - Alvaro Alonso
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Pamela L Lutsey
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - James S Pankow
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA
| | - Weihua Guan
- Division of Biostatistics, University of Minnesota, Minneapolis, MN, USA
| | - Susan Cheng
- Cardiovascular Division, Brigham and Women's Hospital, Boston, MA, USA
| | - Frank A Lederle
- Center for Chronic Disease Outcomes Research, Veterans Affairs Medical Center, Minneapolis, MN, USA
| | - Weihong Tang
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, MN, USA.
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Soepriatna AH, Damen FW, Vlachos PP, Goergen CJ. Cardiac and respiratory-gated volumetric murine ultrasound. Int J Cardiovasc Imaging 2017; 34:713-724. [PMID: 29234935 DOI: 10.1007/s10554-017-1283-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/22/2017] [Indexed: 01/13/2023]
Abstract
Current cardiovascular ultrasound mainly employs planar imaging techniques to assess function and physiology. These techniques rely on geometric assumptions, which are dependent on the imaging plane, susceptible to inter-observer variability, and may be inaccurate when studying complex diseases. Here, we developed a gated volumetric murine ultrasound technique to visualize cardiovascular motion with high spatiotemporal resolution and directly evaluate cardiovascular health. Cardiac and respiratory-gated cine loops, acquired at 1000 frames-per-second from sequential positions, were temporally registered to generate a four-dimensional (4D) dataset. We applied this technique to (1) evaluate left ventricular (LV) function from both healthy mice and mice with myocardial infarction and (2) characterize aortic wall strain of angiotensin II-induced dissecting abdominal aortic aneurysms in apolipoprotein E-deficient mice. Combined imaging and processing times for the 4D technique was approximately 2-4 times longer than conventional 2D approaches, but substantially more data is collected with 4D ultrasound and further optimization can be implemented to reduce imaging times. Direct volumetric measurements of 4D cardiac data aligned closely with those obtained from MRI, contrary to conventional methods, which were sensitive to transducer alignment, leading to overestimation or underestimation of estimated LV parameters in infarcted hearts. Green-Lagrange circumferential strain analysis revealed higher strain values proximal and distal to the aneurysm than within the aneurysmal region, consistent with published reports. By eliminating the need for geometrical assumptions, the presented 4D technique can be used to more accurately evaluate cardiac function and aortic pulsatility. Furthermore, this technique allows for the visualization of regional differences that may be overlooked with conventional 2D approaches.
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Affiliation(s)
- Arvin H Soepriatna
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN, 47907, USA
| | - Frederick W Damen
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN, 47907, USA
| | - Pavlos P Vlachos
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN, 47907, USA.,School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN, 47907, USA
| | - Craig J Goergen
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, IN, 47907, USA.
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Apostolakis IZ, Nandlall SD, Konofagou EE. Piecewise Pulse Wave Imaging (pPWI) for Detection and Monitoring of Focal Vascular Disease in Murine Aortas and Carotids In Vivo. IEEE TRANSACTIONS ON MEDICAL IMAGING 2016; 35:13-28. [PMID: 26168432 PMCID: PMC4703464 DOI: 10.1109/tmi.2015.2453194] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Atherosclerosis and Abdominal Aortic Aneurysms (AAAs) are two common vascular diseases associated with mechanical changes in the arterial wall. Pulse Wave Imaging (PWI), a technique developed by our group to assess and quantify the mechanical properties of the aortic wall in vivo, may provide valuable diagnostic information. This work implements piecewise PWI (pPWI), an enhanced version of PWI designed for focal vascular diseases. Localized, sub-regional PWVs and PWI moduli ( EPWI ) were estimated within 2-4 mm wall segments of murine normal, atherosclerotic and aneurysmal arteries. Overall, stiffness was found to increase in the atherosclerotic cases. The mean sub-regional PWV was found to be 2.57±0.18 m/s for the normal aortas (n = 7) with a corresponding mean EPWI of 43.82±5.86 kPa. A significant increase ( (p ≤ 0.001)) in the group means of the sub-regional PWVs was found between the normal aortas and the aortas of mice on high-fat diet for 20 ( 3.30±0.36 m/s) and 30 weeks ( 3.56±0.29 m/s). The mean of the sub-regional PWVs ( 1.57±0.78 m/s) and EPWI values ( 19.23±15.47 kPa) decreased significantly in the aneurysmal aortas (p ≤ 0.05) . Furthermore, the mean coefficient of determination (r(2)) of the normal aortas was significantly higher (p ≤ 0.05) than those of the aneurysmal and atherosclerotic cases. These findings demonstrated that pPWI may be able to provide useful biomarkers for monitoring focal vascular diseases.
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Affiliation(s)
| | - Sacha D. Nandlall
- Department of Biomedical Engineering Columbia University, New York, NY 10027 USA
| | - Elisa E. Konofagou
- Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027 USA ()
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10
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De Basso R, Sandgren T, Ahlgren ÅR, Länne T. Increased cardiovascular risk without generalized arterial dilating diathesis in persons who do not have abdominal aortic aneurysm but who are first-degree relatives of abdominal aortic aneurysm patients. Clin Exp Pharmacol Physiol 2015; 42:576-81. [PMID: 25882720 DOI: 10.1111/1440-1681.12395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 03/09/2015] [Accepted: 03/27/2015] [Indexed: 11/28/2022]
Abstract
There is a strong genetic predisposition towards abdominal aortic aneurysm (AAA), but it is unknown whether persons without AAA but with first-degree relatives who are AAA patients have a generalized dilating diathesis, defect arterial wall mechanics, or increased cardiovascular risk. The aim of the study was to investigate arterial diameters and wall mechanics at multiple arterial sites in these subjects and compare them with controls without a family history of AAA. This study included 118 first-degree relatives of patients with AAA and 66 controls (age: 40-80 years). The abdominal aorta, common carotid artery, common femoral artery, and popliteal artery were investigated by echo-tracking ultrasound. The relatives had no arterial dilatation, but they did tend to have smaller diameters than controls. Relatives had a higher heart rate, diastolic blood pressure, and mean arterial pressure than controls. The distensibility coefficient and the compliance coefficient were decreased in all arteries in male relatives, adjusted for age and smoking; these coefficients were normalized after adjustment for mean arterial pressure and heart rate. Female relatives had a lower compliance coefficient in the abdominal aorta, adjusted for age and smoking. After adjustment for mean arterial pressure and heart rate, the difference disappeared. No general arterial dilatation in relatives without AAA was found, supporting the hypothesis that the dilating diathesis is linked to the aneurysmal manifestation in the abdominal aorta. Although the threat of aneurysmal dilatation and rupture seems to be lacking in these subjects, heart rate, blood pressure, and arterial wall stiffness were all increased, which may indicate a higher risk of developing cardiovascular morbidity and mortality.
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Affiliation(s)
- Rachel De Basso
- Division of Medical Diagnostics, Department of Clinical Physiology, Region Jönköping County, Jönköping, Sweden.,Department of Natural Science and Biomedicine, School of Health Sciences, Jönköping University, Jönköping, Sweden
| | - Thomas Sandgren
- Department of Surgery, Capio Lundby Hospital, Gothenburg, Sweden
| | - Åsa Rydén Ahlgren
- Clinical Physiology and Nuclearmedicine Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Toste Länne
- Division of Cardiovascular Medicine, Department of Medical and Health Science, Faculty of Health Science, Linköping University, Linköping, Sweden.,Department of Cardiovascular Surgery, Linköping University Hospital, Linköping, Sweden
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Metaxa E, Kontopodis N, Vavourakis V, Tzirakis K, Ioannou CV, Papaharilaou Y. The influence of intraluminal thrombus on noninvasive abdominal aortic aneurysm wall distensibility measurement. Med Biol Eng Comput 2014; 53:299-308. [PMID: 25548097 DOI: 10.1007/s11517-014-1235-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 12/15/2014] [Indexed: 01/24/2023]
Abstract
Abdominal aortic aneurysm wall distensibility can be estimated by measuring pulse pressure and the corresponding sac volume change, which can be obtained by measuring wall displacement. This approach, however, may introduce error if the role of thrombus in assisting the wall in bearing the pulse pressure loading is neglected. Our aim was to introduce a methodology for evaluating and potentially correcting this error in estimating distensibility. Electrocardiogram-gated computed tomography images of eleven patients were obtained, and the volume change between diastole and systole was measured. Using finite element procedures, we determined the equivalent pulse pressure loading that should be applied to the wall of a model where thrombus was digitally removed, to yield the same sac volumetric increase caused by applying the luminal pulse pressure to the model with thrombus. The equivalent instead of the measured pulse pressure was used in the distensibility expression. For a relative volumetric thrombus deposition (V ILT) of 50 %, a 62 % distensibility underestimation resulted when thrombus role was neglected. A strong linear correlation was observed between distensibility underestimation and V ILT. To assess the potential value of noninvasive wall distensibility measurement in rupture risk stratification, the role of thrombus on wall loading should be further investigated.
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Affiliation(s)
- Eleni Metaxa
- Foundation for Research and Technology-Hellas, Institute of Applied and Computational Mathematics, Nikolaou Plastira 100, Vassilika Vouton, 70013, Heraklion, Crete, Greece
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Taniguchi R, Hoshina K, Hosaka A, Miyahara T, Okamoto H, Shigematsu K, Miyata T, Watanabe T. Strain analysis of wall motion in abdominal aortic aneurysms. Ann Vasc Dis 2014; 7:393-8. [PMID: 25593624 DOI: 10.3400/avd.oa.14-00067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 08/21/2014] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE In this exploratory study, we used ultrasound speckle-tracking methods, originally used for analyzing cardiac wall motion, to evaluate aortic wall motion. MATERIALS AND METHODS We compared 19 abdominal aortic aneurysm (AAA) patients with 10 healthy volunteers (diameter, 48 mm vs. 15 mm). Motion pictures of the axial view of the aneurysm using ultrasonography were analyzed. Circumferential strain and strain rate at 6 equally divided segments of the aorta were semiautomatically calculated. We termed 'peak' strain and strain rate as the maximum of strain and strain rate in a cardiac cycle for each segment. We also evaluated the coefficient of variation of peak strain rate for the six segments. RESULTS In the aneurysm and control groups, the mean values of peak strain along the 6 segments were 1.5% ± 0.6% vs. 4.7% ± 1.6% (p <0.0001), respectively. The coefficient of variation of the peak strain rate was higher in the AAA group (0.74 ± 0.20) than in the control group (0.56 ± 0.12; p <0.05). CONCLUSIONS Aortic wall compliance decreased in the more atherosclerotic AAA group. The higher relative dispersion of strain rates in the AAA group is indicative of the inhomogeneous movement of the aortic wall.
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Affiliation(s)
- Ryosuke Taniguchi
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Katsuyuki Hoshina
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Akihiro Hosaka
- Department of Surgery, Tokyo Metropolitan Tama Medical Center, Tokyo, Japan
| | - Takuya Miyahara
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroyuki Okamoto
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kunihiro Shigematsu
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tetsuro Miyata
- Vascular Center, Sanno Hospital and Sanno Medical Center, Tokyo, Japan
| | - Toshiaki Watanabe
- Division of Vascular Surgery, Department of Surgery, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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13
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Hosaka K, Hoh BL. Inflammation and cerebral aneurysms. Transl Stroke Res 2013; 5:190-8. [PMID: 24323732 DOI: 10.1007/s12975-013-0313-y] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/08/2013] [Accepted: 11/14/2013] [Indexed: 01/07/2023]
Abstract
Cerebral aneurysms (CAs) occur in up to 5% of the population in the US, and up to 7% of all strokes are caused by CA rupture. Little is known about the pathophysiology of cerebral aneurysm formation, though inflammatory cells such as macrophages and neutrophils have been found in the walls of CAs. After many studies of both human specimens and experimentally induced animal models of aneurysms, the predominant model for CA formation and progression is as follows: (1) endothelial damage and degeneration of the elastic lamina, (2) inflammatory cell recruitment and infiltration, (3) and chronic remodeling of vascular wall. Endothelial damage can be caused by changes in hemodynamic stress, which results in the upregulation of proinflammatory cytokine secretion followed by the recruitment of various inflammatory cells. This recruitment and subsequent infiltration induces smooth muscle cell proliferation, apoptosis, and remodeling of the artery wall. These complex events are thought to lead to aneurysm rupture. This review will focus on the role of the immune system in the formation and progression of saccular CA and the ways in which the immune response may be modulated to treat aneurysms and prevent rupture.
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Affiliation(s)
- Koji Hosaka
- Department of Neurosurgery, University of Florida, PO Box 100265, Gainesville, FL, 32610, USA,
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14
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Kontopodis N, Georgakarakos E, Metaxa E, Pagonidis K, Papaharilaou Y, Ioannou CV. Estimation of wall properties and wall strength of aortic aneurysms using modern imaging techniques. One more step towards a patient-specific assessment of aneurysm rupture risk. Med Hypotheses 2013; 81:212-5. [PMID: 23714223 DOI: 10.1016/j.mehy.2013.04.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 04/11/2013] [Accepted: 04/27/2013] [Indexed: 11/28/2022]
Abstract
Abdominal aortic aneurysmal disease is a major health problem with rupture representing its main complication accompanied by great mortality. Elective repair is currently performed with mortality rates <3%, based upon size or expansion rate, with a recommended threshold of 5.5 cm maximum diameter or >1cm/year enlargement. It is well established that even small AAAs without indication for surgical repair can experience rupture with catastrophic outcomes whereas larger aneurysms often remain intact for a long period. It is recognized, therefore, that the currently used, maximum diameter criterion can not accurately predict AAAs evolution. There is increasing interest in the role of patient-specific biomechanical profiling of AAA development and rupture. Biomechanically, rupture of a vessel occurs when intravascular forces exceed vessel wall structural endurance. Peak Wall Stress (PWS) has been previously shown to better identify AAAs prone to rupture than maximum diameter, but currently stress analysis takes into account several assumptions that influence results to a large extent and limit their use. Moreover stress represents only one of two determinants of rupture risk according to the biomechanical perspective. Wall strength and mechanical properties on the other hand cannot be assessed in vivo but only ex vivo through mechanical studies with mean values of these parameters taken into account for rupture risk estimations. New possibilities in the field of aortic imaging offer promising tools for the validation and advancement of stress analysis and the in vivo evaluation of AAAs' wall properties and wall strength. Documentation of aortic wall motion during cardiac cycle is now feasible through ECG-gated multi-detector CT imaging offering new possibilities towards an individualized method for rupture risk and expansion-rate predictions based on data acquired in vivo.
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Affiliation(s)
- Nikolaos Kontopodis
- Vascular Surgery Department, University of Crete Medical School, Heraklion, Crete, Greece
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15
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Mouktadiri G, Bou-Saïd B, Walter-Le-Berre H. Aortic endovascular repair modeling using the finite element method. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/jbise.2013.69112] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Stent graft performance in the treatment of abdominal aortic aneurysms: the influence of compliance and geometry. J Biomech 2012; 46:383-95. [PMID: 23218139 DOI: 10.1016/j.jbiomech.2012.11.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 11/09/2012] [Indexed: 11/24/2022]
Abstract
The long-term success of the endovascular procedure for the treatment of Abdominal Aortic Aneurysms (AAAs ) depends on the secure fixation of the proximal end and the geometry of the stent-graft (SG) device. Variations in SG types can affect proximal fixation and SG hemodynamics. Such hemodynamic variations can have a catastrophic effect on the vascular system and may result from a SG/arterial wall compliance mismatch and the sudden decrease in cross-sectional area at the bifurcation, which may result in decreased distal perfusion, increased pressure wave reflection and increased stress at the interface between the stented and non-stented portion of the vessel. To examine this compliance mismatch, a commercial SG device was tested experimentally under a physiological pressure condition in a silicone AAA model based on computed tomography scans. There was a considerable reduction in compliance of 54% and an increase in the pulse wave velocity of 21%, with a significant amount of the forward pressure wave being reflected. To examine the SG geometrical effects, a commercial bifurcated geometry was compared computationally and experimentally with a geometrical taper in the form of a blended section, which provided a smooth transition from the proximal end to both iliac legs. The sudden contraction of commercial SG at the bifurcation region causes flow separation within the iliac legs, which is known to cause SG occlusion and increased proximal pressure. The blended section along the bifurcation region promotes a greater uniformity of the fluid flow field within the distal legs, especially, during the deceleration phase with reduced boundary layer reversal. In order to reduce the foregoing losses, abrupt changes of cross-section should be avoided. Geometrical tapers could lead to improved clinical outcomes for AAA SGs.
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17
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Biomechanics and Pathobiology of Aortic Aneurysms. STUDIES IN MECHANOBIOLOGY, TISSUE ENGINEERING AND BIOMATERIALS 2011. [DOI: 10.1007/8415_2011_84] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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18
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Moloney MA, McHugh S, O’ Donnell DH, Casey RG, Kavanagh EG, Grace PA, Fitzgerald P, Bouchier-Hayes DJ. Comparison of arterial stiffness and microcirculatory changes following abdominal aortic aneurysm grafting. Ir J Med Sci 2010; 180:375-8. [DOI: 10.1007/s11845-010-0513-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 05/24/2010] [Indexed: 10/18/2022]
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19
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Medina F, de Haro J, Florez A, Acin F. Relationship between endothelial dependent vasodilation and size of abdominal aortic aneurysms. Ann Vasc Surg 2010; 24:752-7. [PMID: 20638617 DOI: 10.1016/j.avsg.2009.11.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 11/12/2009] [Accepted: 11/30/2009] [Indexed: 10/19/2022]
Abstract
BACKGROUND Flow-mediated dilation of the brachial artery (FMDB) indirectly reflects the action of nitric oxide liberated by the endothelium. In patients with abdominal aortic aneurysms (AAA), the changes in nitric oxide metabolism in close association with inflammation, appear to play a leading role in the aetiopathology of this disease, although it is still not clear. The objective was to study the correlation and behavior of FMDB relative to the aneurysm diameter (AD). To evaluate the relationship between C-reactive protein (CRP) and the FMDB in these patients. To study the correlation and behavior of FMDB relative to the aneurysm diameter (AD). To evaluate the relationship between C-reactive protein (CRP) and the FMDB in these patients. METHODS The FMDB value and the CRP were determined in a total of 30 patients with an AAA > or =30 mm, confirmed by computed tomography. The cardiovascular and treatment history was recorded, together with the lipid and renal profile and leucocyte count. RESULTS The median AD in the sample was 43 mm (25 percentile: 37 mm; 75 percentile: 60 mm). The primary variables of the study, FMDB and CRP, were the only ones that differed statistically when we stratified the sample according to AD quartiles (p < 0.001). There was a negative correlation between the FMDB and the AD (R = -0.78 [p < 0.001]) and a positive one for CRP (0.74 [p < 0.001]). The CRP/FMDB gave an R value of -0.56 (p = 0.001). CONCLUSION Endothelium dependent vasodilation has a linear and negative correlation with the AD. The positive correlation between the FMDB and CRP supports the hypothesis that inflammation and endothelial dysfunction are processes associated with the physiopathology of AAA and vary with their growth.
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Affiliation(s)
- Francisco Medina
- Department of Angiology and Vascular Surgery, General Yagüe Hospital, Burgos, Spain
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20
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Corbett TJ, Molony DS, Callanan A, McGloughlin TM. The effect of vessel material properties and pulsatile wall motion on the fixation of a proximal stent of an endovascular graft. Med Eng Phys 2010; 33:106-11. [PMID: 20947409 DOI: 10.1016/j.medengphy.2010.09.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 09/21/2010] [Accepted: 09/22/2010] [Indexed: 10/18/2022]
Abstract
Migration is a serious failure mechanism associated with endovascular abdominal aortic aneurysm (AAA) repair (EVAR). The effect of vessel material properties and pulsatile wall motion on stent fixation has not been previously investigated. A proximal stent from a commercially available stent graft was implanted into the proximal neck of silicone rubber abdominal aortic aneurysm models of varying proximal neck stiffness (β=25.39 and 20.44). The stent was then dislodged by placing distal force on the stent struts. The peak force to completely dislodge the stent was measured using a loadcell. Dislodgment was performed at ambient pressure with no flow (NF) and during pulsatile flow (PF) at pressures of 120/80 mmHg and 140/100 mmHg to determine if pulsatile wall motions affected the dislodgement force. An imaging analysis was performed at ambient pressure and at pressures of 120 mmHg and 140 mmHg to investigate diameter changes on the model due to the radial force of the stent and internal pressurisation. Stent displacement forces were ~50% higher in the stiffer model (7.16-8.4 N) than in the more compliant model (3.67-4.21 N). The mean displacement force was significantly reduced by 10.95-12.83% from the case of NF to the case of PF at 120/80 mmHg. A further increase in pressure to 140/120 mmHg had no significant effect on the displacement force. The imaging analysis showed that the diameter in the region of the stent was 0.37 mm greater in the less stiff model at all the pressures which could reduce the fixation of the stent. The results suggest that the fixation of passively fixated aortic stents could be comprised in more compliant walls and that pulsatile motions of the wall can reduce the maximum stent fixation.
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Affiliation(s)
- T J Corbett
- Centre for Applied Biomedical Engineering Research (CABER), MSSi, Department of Mechanical and Aeronautical Engineering, University of Limerick, Limerick, Ireland
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21
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Patient-specific biomechanical profiling in abdominal aortic aneurysm development and rupture. J Vasc Surg 2010; 52:480-8. [DOI: 10.1016/j.jvs.2010.01.029] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 01/07/2010] [Accepted: 01/10/2010] [Indexed: 11/20/2022]
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22
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Johnsen SH, Forsdahl SH, Singh K, Jacobsen BK. Atherosclerosis in abdominal aortic aneurysms: a causal event or a process running in parallel? The Tromsø study. Arterioscler Thromb Vasc Biol 2010; 30:1263-8. [PMID: 20360536 DOI: 10.1161/atvbaha.110.203588] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The pathogenesis of abdominal aortic aneurysm (AAA) formation is poorly understood. We investigated the relationship between carotid, femoral, and coronary atherosclerosis and abdominal aortic diameter, and whether atherosclerosis was a risk marker for AAA. METHODS AND RESULTS Ultrasound of the right carotid artery, the common femoral artery, and the abdominal aorta was performed in 6446 men and women from a general population. The burden of atherosclerosis was assessed as carotid total plaque area, common femoral lumen diameter, and self-reported coronary heart disease. An AAA was defined as maximal infrarenal aortic diameter > or =30 mm. No dose-response relationship was found between carotid atherosclerosis and abdominal aortic diameter <27 mm. However, significantly more atherosclerosis and coronary heart disease was found in aortic diameter > or =27 mm and in AAAs. The age- and sex-adjusted odds ratio (OR) (95% CI) for AAA in the top total plaque area quintile was 2.3 (1.5 to 3.4), as compared with subjects without plaques. The adjusted OR (95% CI) was 1.7 (1.1 to 2.6). No independent association was found between femoral lumen diameter and AAA. CONCLUSIONS The lack of a consistent dose-response relationship between atherosclerosis and abdominal aortic diameter suggests that atherosclerosis may not be a causal event in AAA but develops in parallel with or secondary to aneurismal dilatation.
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Affiliation(s)
- Stein Harald Johnsen
- Department of Neurology, University Hospital North Norway, N-9038 Tromsø, Norway.
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23
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Deguchi JO, Huang H, Libby P, Aikawa E, Whittaker P, Sylvan J, Lee RT, Aikawa M. Genetically engineered resistance for MMP collagenases promotes abdominal aortic aneurysm formation in mice infused with angiotensin II. J Transl Med 2009; 89:315-26. [PMID: 19153555 PMCID: PMC2932654 DOI: 10.1038/labinvest.2008.167] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Clinical evidence links increased aortic collagen content and stiffness to abdominal aortic aneurysm (AAA) formation. However, the possibility that excess collagen contributes to AAA formation remains untested. We investigated the hypothesis that augmented collagen promotes AAA formation, and employed apoE-null mice expressing collagenase-resistant mutant collagen (Col(R/R)/apoE(-/-)), heterozygote (Col(R/+)/apoE(-/-)), or wild-type collagen (Col(+/+)/apoE(-/-)) infused with angiotensin II to induce AAA. As expected, the aortas of Col(R/R)/apoE(-/-) mice contained more interstitial collagen than those from the other groups. Angiotensin II treatment elicited more AAA formation in Col(R/R)/apoE(-/-) mice than Col(R/+)/apoE(-/-) or Col(+/+)/apoE(-/-) mice. Aortic circumferences correlated positively with collagen content, determined by picrosirius red and Masson trichrome staining. Mechanical testing of aortas of Col(R/R)/apoE(-/-) mice showed increased stiffness and susceptibility to mechanical failure compared to those of Col(+/+)/apoE(-/-) mice. Optical analysis further indicated altered collagen fiber orientation in the adventitia of Col(R/R)/apoE(-/-) mice. These results demonstrate that collagen content regulates aortic biomechanical properties and influences AAA formation.
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Affiliation(s)
- Jun-o Deguchi
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Hayden Huang
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Peter Libby
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Elena Aikawa
- Center for Molecular Imaging Research, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA
| | - Peter Whittaker
- Department of Emergency Medicine, Wayne State University, Detroit, MI
| | - Jeremy Sylvan
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Richard T. Lee
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
| | - Masanori Aikawa
- Cardiovascular Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA
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24
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Johnsen SH, Joakimsen O, Singh K, Stensland E, Forsdahl SH, Jacobsen BK. Relation of common carotid artery lumen diameter to general arterial dilating diathesis and abdominal aortic aneurysms: the Tromsø Study. Am J Epidemiol 2009; 169:330-8. [PMID: 19066307 DOI: 10.1093/aje/kwn346] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In a cross-sectional, population-based study in Tromsø, Norway, the authors investigated correlations between lumen diameter in the right common carotid artery (CCA) and the diameters of the femoral artery and abdominal aorta and whether CCA lumen diameter was a risk factor for abdominal aortic aneurysm (AAA). Ultrasonography was performed in 6,400 men and women aged 25-84 years during 1994-1995. An AAA was considered present if the aortic diameter at the level of renal arteries was greater than or equal to 35 mm, the infrarenal aortic diameter was greater than or equal to 5 mm larger than the diameter of the level of renal arteries, or a localized dilation of the aorta was present. CCA lumen diameter was positively correlated with abdominal aortic diameter (r = 0.3, P < 0.01) and femoral artery diameter (r = 0.2, P < 0.01). In a multivariable adjusted model, CCA lumen diameter was a significant predictor of AAA in both men and women (for the fifth quintile vs. the third, odds ratios were 1.9 (95% confidence interval: 1.2, 2.9) and 4.1 (95% confidence interval: 1.5, 10.8), respectively). Thus, CCA lumen diameter was positively correlated with femoral and abdominal aortic artery diameter and was an independent risk factor for AAA.
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MESH Headings
- Aged
- Aorta, Abdominal/diagnostic imaging
- Aorta, Abdominal/pathology
- Aortic Aneurysm, Abdominal/diagnostic imaging
- Aortic Aneurysm, Abdominal/epidemiology
- Aortic Aneurysm, Abdominal/pathology
- Carotid Artery, Common/diagnostic imaging
- Carotid Artery, Common/pathology
- Comorbidity
- Cross-Sectional Studies
- Diabetes Mellitus/epidemiology
- Dilatation, Pathologic/diagnostic imaging
- Dilatation, Pathologic/epidemiology
- Dilatation, Pathologic/pathology
- Disease Susceptibility/diagnostic imaging
- Disease Susceptibility/epidemiology
- Disease Susceptibility/pathology
- Female
- Femoral Artery/diagnostic imaging
- Femoral Artery/pathology
- Hemorrhagic Disorders/diagnostic imaging
- Hemorrhagic Disorders/epidemiology
- Hemorrhagic Disorders/pathology
- Humans
- Male
- Middle Aged
- Norway/epidemiology
- Risk Factors
- Smoking/epidemiology
- Ultrasonography
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Sandrock M, Hansel J, Schulze J, Schmitz D, Niess A, Burkhardt H, Schmidt-Trucksaess A. Sequentially based analysis versus image based analysis of Intima Media Thickness in common carotid arteries studies - do major IMT studies underestimate the true relations for cardio- and cerebrovascular risk? Cardiovasc Ultrasound 2008; 6:32. [PMID: 18570651 PMCID: PMC2443112 DOI: 10.1186/1476-7120-6-32] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2008] [Accepted: 06/20/2008] [Indexed: 11/10/2022] Open
Abstract
Background Image-based B-mode ultrasound has gained popularity in major studies as a non-invasive method of measuring cardio- and cerebrovascular risk factors. However, none of the major studies appears to have paid sufficient attention to the variation in end diastolic wall process. By using sequentially based analyses (SBA) of Intima-Media Thickness (IMT), the general purpose of this study was to show that the current image based (ECG tracked) analysis (IBA) has some major variations and might underestimate the true relations for cardiovascular events and stroke for IMT measurement. Method The study group consisted of 2500 healthy male subjects aged between 35 to 55 years. 4 sequences (300 images) were analyzed per subject. 750,000 images were analysed throughout the course of this study. Results IBA showed significantly lower mean, maximal, and minimal values for IMT in CCA than for SBA. The correlation analysis between IBA and SBA with the cardio- and cerebrovascular risk factors showed a higher correlation of SBA for all risk factors. The Pearson coefficient was 0.81, p < 0.01, for SBA versus Framingham CHD risk level (FCRL) and 0.49, p = 0.01, for IBA versus FCRL. Conclusion IBA did not measure the true maximal values of the IMT in this study. Together with the correlation analysis, this indicates that IBA might underestimate the true relations for IMT and risk factors.
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Affiliation(s)
- M Sandrock
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, D-72074 Tuebingen, Germany.
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26
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Gao F, Ohta O, Matsuzawa T. Fluid-structure interaction in layered aortic arch aneurysm model: assessing the combined influence of arch aneurysm and wall stiffness. ACTA ACUST UNITED AC 2008; 31:32-41. [DOI: 10.1007/bf03178451] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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27
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Volokh K, Vorp D. A model of growth and rupture of abdominal aortic aneurysm. J Biomech 2008; 41:1015-21. [DOI: 10.1016/j.jbiomech.2007.12.014] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 12/20/2007] [Accepted: 12/12/2007] [Indexed: 12/01/2022]
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28
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Powell JT, Länne T. Through thick and thin collagen fibrils, stress, and aortic rupture: another piece in the jigsaw. Circulation 2007; 115:2687-8. [PMID: 17533194 DOI: 10.1161/circulationaha.107.709139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
Rupture of abdominal aortic aneurysm (AAA) represents a significant clinical event, having a mortality rate of 90% and being currently ranked as the 13th leading cause of death in the US. The ability to reliably evaluate the susceptibility of a particular AAA to rupture on a case-specific basis could vastly improve the clinical management of these patients. Because AAA rupture represents a mechanical failure of the degenerated aortic wall, biomechanical considerations are important to understand this process and to improve our predictions of its occurrence. Presented here is an overview of research to date related to the biomechanics of AAA rupture. This includes a summary of results related to ex vivo and in vivo mechanical testing, noninvasive AAA wall stress estimations, and potential mechanisms of AAA wall weakening. We conclude with a demonstration of a biomechanics-based approach to predicting AAA rupture on a patient-specific basis, which may ultimately prove to be superior to the widely and currently used maximum diameter criterion.
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Affiliation(s)
- David A Vorp
- Department of Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 100 Technology Drive, Suite 200, Pittsburgh, PA 15219, USA.
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30
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Abstract
Visceral artery aneurysms represent 0.1% to 0.2% of all vascular aneurysms. They are mostly asymptomatic, but rupture is associated with a high mortality rate. We present a case of an asymptomatic aneurysm of the proximal superior mesenteric artery in a 64-year-old man that was successfully treated by implantation of a covered stent graft. The use of endovascular techniques to manage visceral artery aneurysms should be considered.
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Affiliation(s)
- R Drescher
- Institute of Diagnostic and Interventional Radiology, St. Josef Hospital, Ruhr-University Bochum, 44791, Bochum, Gudrunstrasse 56, Germany.
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31
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Long A, Rouet L, Bissery A, Rossignol P, Mouradian D, Sapoval M. Compliance of abdominal aortic aneurysms evaluated by tissue Doppler imaging: Correlation with aneurysm size. J Vasc Surg 2005; 42:18-26. [PMID: 16012447 DOI: 10.1016/j.jvs.2005.03.037] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Several studies have shown that an increase in abdominal aortic aneurysm (AAA) growth rate occurs when the diameter reaches 40 to 50 mm. AAA expansion is related to remodeling of the parietal extracellular matrix. The parietal mechanisms involved in this critical phase of sudden increase remain unexplained. Analysis of AAA wall movements and determination of AAA compliance may provide information about the constitution of the arterial wall. If a change in parietal wall motion somewhere between 40 and 50 mm could be shown, this would contribute to the understanding of the growth of AAA. Furthermore, it would provide a valuable additional parameter for AAA monitoring. This study had two aims: first, to evaluate the relationship between AAA compliance and maximum diameter using the tissue Doppler imaging system; and second, to test the hypothesis of a change in AAA behavior at around 45 mm in diameter. METHODS Fifty-six patients with AAA (mean diameter, 39 mm) were prospectively investigated using the tissue Doppler imaging system, which provides information concerning arterial wall motion. Maximum mean segmental dilation (MMSD), segmental compliance, pressure strain elastic modulus (Ep), and stiffness were determined and related to the maximum diameter of AAA. Results After natural log transformation of all variables, there was a significant positive linear relationship between maximum diameter and both MMSD (P < .001) and segmental compliance (P < .001) but not with Ep or stiffness (P = .37 and .22, respectively). MMSD and segmental compliance were significantly higher in AAA > or = 45 mm than in AAA < 45 mm (P < .0002 and <. 004, respectively). Ep and stiffness tended to decrease in larger AAAs, but this was not statistically significant (P < .43 and .24, respectively). Dispersion of Ep and stiffness values seemed to be wider among AAA < 45 mm compared with those > or = 45 mm. CONCLUSION Compliance parameters can easily be measured during routine AAA ultrasound monitoring using the tissue Doppler imaging system. The study showed an increase in MMSD and segmental compliance as well as a nonsignificant trend toward increased distensibility (decreased Ep and stiffness) with increased AAA diameter. A change in dispersion of AAA distensibility may appear around 45 mm in diameter, but a larger study will be needed to clarify this.
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Affiliation(s)
- Anne Long
- Department of Cardiovascular Radiology, Hôpital Européen Georges Pompidou, the Philips Medical Imaging Systems, France.
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Iwamoto T, Kimura A, Nakai T, Kanaya K, Ishimaru S. Implications of carotid arteriomegaly in patients with aortic aneurysm. J Atheroscler Thromb 2005; 11:348-53. [PMID: 15644589 DOI: 10.5551/jat.11.348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The pathophysiology of aortic aneurysm is complex and it has remained unclear how frequently arteriomegaly, a diffuse dilatation of the artery, is associated with aneurysm. Therefore, ultrasonic study of the carotid artery was conducted to clarify this issue in a large number of subjects. Carotid ultrasonography was performed in 1,108 Japanese men aged 50 or older, and the results of 379 patients with arteriosclerotic aortic aneurysm (AA) were compared with those of 211 patients with peripheral arterial disease, 65 patients with aortic dissection, 232 hypertensive subjects, and 221 normotensive subjects. The carotid diameter was measured bilaterally at two points on the common carotid artery, and we defined carotid arteriomegaly as an arterial diameter in the 95th percentile or above that in the normotensive control group according to the relevant age subgroups. The incidence of carotid arteriomegaly in the AA group (25.9%) was significantly higher than in the other groups (p < 0.01) even when adjusted for body height and blood pressure. In the arteriomegaly subgroup, hypertension and cigarette smoking was significantly more frequent than in the non-dilated artery subgroup. This study demonstrates that one fourth of patients with aortic aneurysm have arteriomegaly as a generalized systemic abnormality in the arterial wall.
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Affiliation(s)
- Toshihiko Iwamoto
- The Brain & Blood Vessel Laboratory, Tokyo Medical University Hospital, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023 Japan.
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van Laake LW, Vainas T, Dammers R, Kitslaar PJEHM, Hoeks APG, Schurink GWH. Systemic dilation diathesis in patients with abdominal aortic aneurysms: a role for matrix metalloproteinase-9? Eur J Vasc Endovasc Surg 2005; 29:371-7. [PMID: 15749037 DOI: 10.1016/j.ejvs.2005.01.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2004] [Accepted: 01/17/2005] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Accumulating evidence suggests that patients with abdominal aortic aneurysm (AAA) suffer from a systemic dilating condition affecting all arteries. Matrix metalloproteinases (MMPs) and their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), appear to be involved in aneurysm formation, as evidenced by increased aortic tissue MMP activity and plasma MMP levels in patients with AAA. Hypothesizing that an imbalance in plasma MMP/TIMP level might be associated with a systemic dilation diathesis, we studied mechanical vessel wall properties of non-affected arteries of patients with either AAA or aorto-iliac obstructive lesions in association with plasma MMP-9 and TIMP-1 levels. METHODS Twenty-two patients with AAA and 12 with aorto-iliac occlusive disease (AOD) were included. Diastolic diameter (d) and distension (Deltad) were measured at the level of the common carotid artery (CCA) and suprarenal aorta (SA) using ultrasonography. Distensibility (DC) and compliance (CC) were calculated from d, Deltad and brachial pulse pressure. Plasma MMP-9 and TIMP-1 were determined with specific immunoassays. RESULTS The average (+/-SD) age was 72.3+/-5.6 and 65.0+/-8.2 years for the AAA and AOD patients, respectively, (P=0.005). CCA diameter was 9.1+/-1.3mm in AAA patients and AOD 7.8+/-1.4mm in AOD patients, P=0.009. This difference persisted after correction for age. Plasma MMP-9 and TIMP-1 did not differ significantly between AAA and AOD patients. In the total 34 patients, the MMP-9/TIMP-1 ratio was correlated inversely with distensibility (r=-0.74, P=0.002) and to compliance (r=-0.58, P=0.024) of the suprarenal aorta. CONCLUSIONS The CCA diameter was larger in AAA patients compared to AOD patients. MMP-9/TIMP-1 ratio was associated with decreased distensibility and compliance of the suprarenal aorta. These data support the idea that AAA patients exhibit a systemic dilation diathesis, which might be attributable to MMP/TIMP imbalances.
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Affiliation(s)
- L W van Laake
- Department of Surgery, University Hospital Maastricht, 6202 AZ Maastricht, The Netherlands
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Morris L, Delassus P, Walsh M, McGloughlin T. A mathematical model to predict the in vivo pulsatile drag forces acting on bifurcated stent grafts used in endovascular treatment of abdominal aortic aneurysms (AAA). J Biomech 2004; 37:1087-95. [PMID: 15165879 DOI: 10.1016/j.jbiomech.2003.11.014] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2003] [Indexed: 10/26/2022]
Abstract
Endovascular treatment of abdominal aortic aneurysms (AAA) is a promising new alternative to the traditional surgical repair. However, the endovascular approach suffers problems such as stent graft migration, endoleaks and stent mechanism breakage. Fatigue failure is believed to be the major cause of stent graft migration and device breakage. Knowledge of the in vivo forces acting on such devices is a basic requirement for the design of a successful endovascular device. Using a Fourier series trigonometric fit of a typical pressure and flow relationship, a mathematical model, using the control volume method, was developed to predict the pulsatile drag forces acting on various bifurcated stent graft geometries. It was found that for an iliac angle of 30 degrees, a proximal diameter of 24 mm and an iliac diameter of 12 mm, the drag force varied, over the cardiac cycle, between 3.9 and 5.5 N in the axial direction. It was noted that for a specific iliac angle the drag force variation with proximal diameter approximates a quadratic fit, with an increase in proximal diameter producing an increase in drag force. The more compliant the aorta the higher the drag force. Previously published results demonstrated the axial loads (axial drag forces) required for stent graft migration for certain stents types are lower than the drag forces calculated in this study. It is believed that the results of this study can provide guidelines for the quantitative analyses of the in vivo drag forces experienced by stent grafts and could therefore be used as design criteria for such devices.
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Affiliation(s)
- L Morris
- Department of Mechanical and Aeronautical Engineering, Biomedical Engineering Research Centre, University of Limerick, Castletroy, Limerick, Ireland
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Dijk JM, van der Graaf Y, Grobbee DE, Banga JD, Bots ML. Increased Arterial Stiffness Is Independently Related to Cerebrovascular Disease and Aneurysms of the Abdominal Aorta. Stroke 2004; 35:1642-6. [PMID: 15143289 DOI: 10.1161/01.str.0000130513.77186.26] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Arterial stiffness is a risk factor for stroke and myocardial infarction. We investigated whether carotid arterial stiffness is related to other localizations of manifest arterial disease.
Methods—
Carotid artery stiffness was measured by ultrasonography as the change in diameter in systole relative to the diastolic diameter in patients enrolled in the Second Manifestations of Arterial Disease (SMART) Study, a cohort study among patients with manifest cardiovascular disease or cardiovascular risk factors. The first consecutive 1561 patients with manifest cardiovascular disease were classified in 4 categories: cerebrovascular disease, coronary artery disease, peripheral artery disease, or aneurysm of the abdominal aorta (AAA). Differences in arterial stiffness among the categories were studied by linear regression analyses. Patients with coronary artery disease as single diagnosis (n=482) served as reference group.
Results—
Patients with cerebrovascular disease (arterial distension −42.0 μm [95% CI, −57.2 to −26.8]) and those with an AAA (−64.4 μm [95% CI, −84.8 to −44.0]) had an increased carotid stiffness compared with the reference group. Adjustment for confounders attenuated the relations, which remained statistically significant (−34.2 μm [95% CI, −47.8 to −20.7] and −33.2 μm [95% CI, −51.8 to −14.6], respectively).
Conclusion—
Our study suggests that increased arterial stiffness is important in the pathophysiology of especially cerebrovascular disease and AAA. That the differences in arterial stiffness between disease categories attenuated after adjustment for important risk factors but remained significant suggests that besides being an element in the causal pathway, arterial stiffness is also a risk factor for cardiovascular disease itself.
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Affiliation(s)
- J M Dijk
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Huispostnummer Str 6.131, PO Box 85060, 3508 BA Utrecht, The Netherlands.
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Debasso R, Astrand H, Bjarnegård N, Rydén Ahlgren A, Sandgren T, Länne T. The popliteal artery, an unusual muscular artery with wall properties similar to the aorta: implications for susceptibility to aneurysm formation? J Vasc Surg 2004; 39:836-42. [PMID: 15071452 DOI: 10.1016/j.jvs.2003.12.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The popliteal artery is, after the aorta, the most common site for aneurysm formation. Why the popliteal artery is more susceptible than other peripheral muscular arteries is unknown. An important factor may be differences in arterial wall composition as compared with other peripheral muscular arteries, which in turn affect wall properties. These are however unknown. We studied the mechanical wall properties of the popliteal artery in healthy subjects. MATERIAL AND METHODS An ultrasound echo-tracking system was used to measure pulsatile changes in popliteal diameter in 108 healthy subjects (56 female, 52 male; age range, 9-82 years). In combination with blood pressure, stiffness (beta), strain, cross-sectional artery wall compliance coefficient (CC), and distensibility coefficient (DC) were calculated. Intima-media thickness (IMT) was registered with a Philips P700 ultrasound scanner. RESULTS The popliteal diameter increased with age, and was larger in male subjects than in female subjects (P<.001). Fractional diameter change (strain) decreased with age (P<.001), and strain values were lower in male subjects than in female subjects (P<.01). Accordingly, stiffness increased with age (P<.001), with higher stiffness values in male subjects (P<.01). DC decreased with age (P<.001), with lower DC values in male subjects (P<.01). CC decreased with age, with no difference between genders (P<.001). IMT increased with age (P<.001), with higher IMT values in male subjects (P<.001). The increase in IMT did not affect distensibility. CONCLUSION The wall properties of the popliteal artery are affected by age and gender, not only with an increase in diameter, but also with an age-related decrease in distensibility, with male subjects having lower distensibility than in female subjects. This seems not to be the behavior of a true muscular artery, but of a central elastic artery, such as the aorta, and might have implications for susceptibility to arterial dilatation, as well as the association of aneurysm formation between the aorta and the popliteal artery. CLINICAL RELEVANCE The popliteal artery is, after the abdominal aorta, the most common location for aneurysm formation in the arterial system. Why it is more susceptible than other arteries is unknown. This study shows that the wall function of the popliteal artery differs from other peripheral arteries, and instead show striking similarities to the abdominal aorta, indicating that the functional arrangement of arterial wall components are similar in the two arteries. This may have implications for the susceptibility to aneurysm formation, as well as the association of dilating disease between the popliteal artery and the abdominal aorta.
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Affiliation(s)
- R Debasso
- Department of Medicine and Care, University of Linköping, Sweden.
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Nunnelee JD, Spaner SD. The quality of research on physical examination for abdominal aortic aneurysm. JOURNAL OF VASCULAR NURSING 2004; 22:14-8. [PMID: 14981498 DOI: 10.1016/s1062-0303(03)00103-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A review of nursing literature revealed no studies regarding physical examination or other interventions (except unit based) for abdominal aortic aneurysms (AAA). The physician literature was explored, revealing an excellent meta-analysis in 1999 of studies before that date with regard to physician accuracy in physical examination for AAA. These are reviewed for quality and recommendations made for nursing research and the role of the Society for Vascular Nursing in teaching nurses.
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Ramnarine KV, Hartshorne T, Sensier Y, Naylor M, Walker J, Naylor AR, Panerai RB, Evans DH. Tissue Doppler imaging of carotid plaque wall motion: a pilot study. Cardiovasc Ultrasound 2003; 1:17. [PMID: 14687422 PMCID: PMC320493 DOI: 10.1186/1476-7120-1-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2003] [Accepted: 12/19/2003] [Indexed: 11/10/2022] Open
Abstract
Background Studies suggest the physical and mechanical properties of vessel walls and plaque may be of clinical value in the diagnosis and treatment of cardiovascular atherosclerotic disease. The purpose of this pilot study was to investigate the potential clinical application of ultrasound Tissue Doppler Imaging (TDI) of Arterial Wall Motion (AWM) and to quantify simple wall motion indices in normal and diseased carotid arteries. Methods 224 normal and diseased carotid arteries (0–100% stenoses) were imaged in 126 patients (age 25–88 years, mean 68 ± 11). Longitudinal sections of the carotid bifurcation were imaged using a Philips HDI5000 scanner and L12-5 probe under optimized TDI settings. Temporal and spatial AWMs were analyzed to evaluate the vessel wall displacements and spatial gradients at peak systole averaged over 5 cardiac cycles. Results AWM data were successfully extracted in 91% of cases. Within the carotid bifurcation/plaque region, the maximum wall dilation at peak systole ranged from -100 to 750 microns, mean 335 ± 138 microns. Maximum wall dilation spatial gradients ranged 0–0.49, mean 0.14 ± 0.08. The AWM parameters showed a wide variation and had poor correlation with stenoses severity. Case studies illustrated a variety of pertinent qualitative and quantitative wall motion features related to the biophysics of arterial disease. Conclusion Our clinical experience, using a challenging but realistic imaging protocol, suggests the use of simple quantitative AWM measures may have limitations due to high variability. Despite this, pertinent features of AWM in normal and diseased arteries demonstrate the potential clinical benefit of the biomechanical information provided by TDI.
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Affiliation(s)
- Kumar V Ramnarine
- Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Tim Hartshorne
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Yvonne Sensier
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - May Naylor
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Joanne Walker
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - A Ross Naylor
- Department of Surgery, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Ronney B Panerai
- Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - David H Evans
- Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK
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Rodin MB, Daviglus ML, Wong GC, Liu K, Garside DB, Greenland P, Stamler J. Middle age cardiovascular risk factors and abdominal aortic aneurysm in older age. Hypertension 2003; 42:61-8. [PMID: 12796281 DOI: 10.1161/01.hyp.0000078829.02288.98] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Few prospective studies have examined associations between major cardiovascular risk factors and occurrence of abdominal aortic aneurysm; findings from cross-sectional studies are inconsistent. This long-term population-based study assessed relationships of major risk factors in middle-age to clinical nonfatal plus fatal abdominal aortic aneurysm in older-age in the Chicago Heart Association Detection Project in Industry cohort--10 574 men and 8700 women baseline ages 40 to 64 years screened for risk factors in 1967-1973 at workplaces. With average follow-up of 30 years and clinical cases identified from Medicare records and death certificates, risk factor relationships to abdominal aortic aneurysm occurrence were assessed by Cox regression. There were among men 309 cases and among women, 109--most from Medicare records. Most findings were qualitatively similar for men and women. In multivariate analyses (5 models), hazard ratios for abdominal aortic aneurysm were significantly greater for men than women (> or =1.97), with older age (> or =1.63/5 years), higher serum cholesterol (> or =1.30/40.0 mg/dL), cigarettes/d (> or =2.43/20 cigarettes), past smoking (> or =1.41), height (> or =1.17/7 cm), evidence of adverse blood pressure (hazard ratio 1.10/20 mm Hg higher systolic pressure, 1.12 to 1.14/12 mm Hg higher diastolic pressure, 1.87 with history of treated hypertension). It is concluded that major cardiovascular risk factors--serum cholesterol, smoking, and blood pressure--in middle age relate significantly to risk of abdominal aortic aneurysm in persons surviving into older age.
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Affiliation(s)
- Miriam B Rodin
- Division of Geriatrics, Department of Medicine, University of Chicago Pritzker School of Medicine, Chicago, USA
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Cheng KS, Tiwari A, Baker CR, Morris R, Hamilton G, Seifalian AM. Impaired carotid and femoral viscoelastic properties and elevated intima-media thickness in peripheral vascular disease. Atherosclerosis 2002; 164:113-20. [PMID: 12119200 DOI: 10.1016/s0021-9150(02)00042-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND We undertook a study to determine whether peripheral vascular disease of the lower extremity (PVD) per se affects the arterial viscoelastic properties and intima-media thickness (IMT) of the carotid and femoral arteries. METHODS Thirty-five patients with PVD, 35 age- and gender-matched control subjects were examined with ultrasound scan wall tracking system, with the simultaneous measurement of blood pressure for carotid and femoral IMT and viscoelastic properties. RESULTS Subjects with PVD have significantly impaired carotid elastic properties including compliance (mean (SD): 6.50 (2.39) vs 9.93 (4.07) %mmHg(-1)x10(-2), P<0.001), Petersen's elastic modulus (1.77 (0.69) vs 1.19 (0.63) mmHg x 10(3), P=0.001) and stiffness index (17.92 (7.21) vs 12.10 (6.17), P=0.001) when compared to non-PVD controls. They also have significantly altered femoral elastic properties including Petersen's elastic modulus (5.94 (4.98) vs 3.64 (3.27) mmHg x 10(3), P=0.025) and stiffness index (58.42 (47.76) vs 36.96 (33.43), P=0.033). The carotid (0.85 (0.35) vs 0.59 (0.23) mm, P<0.001) and femoral (1.05 (0.39) vs 0.69 (0.31) mm, P<0.001) IMTs are also significantly elevated in PVD patients. After adjustment for the presumed cardiovascular load assessed on the basis of a cumulative total vascular risk score, as well as age, systolic and diastolic pressure, the carotid viscoelastic indices and the carotid and femoral IMTs remained highly significant. However, the difference in femoral elastic variables was no longer evident. CONCLUSION PVD per se affects the femoral and carotid wall mechanics and morphology similarly to other cardiovascular risk factors and events. These parameters may provide further information for cardiovascular risk assessment in addition to the classical risk factors and the Framingham equation. Indeed, some guidelines have suggested that additional factors such as the carotid scan may influence the clinician's decision to intervene with therapy.
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Affiliation(s)
- Koon-Sung Cheng
- Cardiovascular Haemodynamic Unit, University Department of Surgery, Royal Free and University College Medical School, University College London and The Royal Free Hospital, Pond Street, NW3 2QG, London, UK
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Goodall S, Crowther M, Bell PR, Thompson MM. The association between venous structural alterations and biomechanical weakness in patients with abdominal aortic aneurysms. J Vasc Surg 2002; 35:937-42. [PMID: 12021710 DOI: 10.1067/mva.2002.122877] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Abdominal aortic aneurysms (AAAs) are associated with generalized arterial dilation, torturosity, and altered matrix composition, which suggests a generalized systemic weakness throughout the entire vasculature. The aim of this study was to determine whether this phenomenon was present in the venous tissue of patients with AAA. METHODS A segment of inferior mesenteric vein was harvested from patients who underwent aneurysm repair (n = 11) or colectomy for diverticulosis (n = 11; control). Matrix composition of the vessel was determined with stereology, and dimensions were measured with a computerized image analysis system. Stress-strain measurements were calculated with elongation of inferior mesenteric vein tissue with a tensile-testing machine. RESULTS Histologic examination results showed fragmentation of elastin fibers within the medial layer of venous tissue obtained from patients with AAA. The medial elastin content in tissue from patients with aneurysms was 19.4%, compared with 26.8% in the control group (P =.018). Mechanical test results revealed a significant reduction in the tensile strength from 2.885 MPa in the control group to 1.405 MPa in the AAA group (P =.007). This reduction corresponded with a significant reduction of 59% in the stiffness of the vessel, with the mean Young's modulus of elasticity in the AAA group being 2.72 MPa, compared with 5.361 MPa in the control group (P =.0005). CONCLUSION Reduction in tensile strength and stiffness in venous tissue from patients with AAA was associated with disruption and reduction of the elastin content of the vein wall. These changes are analogous to those observed in the arterial aneurysmal wall and confirm the systemic nature of this disorder.
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Affiliation(s)
- Stephen Goodall
- Department of Surgery, Clinical Sciences Building, Royal Infirmary, University of Leicester, Leicester LE2 7LX, UK
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Knipp BS, Peterson DA, Rajagopalan S, Kehrer C, Ford JW, D'Alecy LG, Whitesall SE, Eagleton MJ, Wakefield TW, Henke PK, Jacobs LA, Greenfield LJ, Stanley JC, Upchurch GR. Impaired vasoreactivity despite an increase in plasma nitrite in patients with abdominal aortic aneurysms. J Vasc Surg 2002; 35:363-7. [PMID: 11854736 DOI: 10.1067/mva.2002.121069] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE This investigation was designed to determine whether differences in vasoreactivity occur in patients with abdominal aortic aneurysms (AAAs) as compared with patients with peripheral arterial occlusive disease (PAOD) or individuals (controls) without known vascular disease. METHODS Brachial artery vasoreactivity was assessed in a blinded fashion, after endothelium-dependent (ED) and endothelium-independent (EI) flow-mediated vasodilation, in age-matched, male patients with AAAs (n = 11) or PAOD (n = 9) or in controls (n = 10). There were no significant differences in prestudy systolic or diastolic blood pressure, body mass index, or antilipidemic medications among the groups studied. Exclusion criteria included diabetes and tobacco use within 3 months. Quantitative ultrasound scan measurements of brachial artery diameters were performed at rest and after either forearm ischemia (ED) or administration of 0.4 mg sublingual nitroglycerin (EI). Plasma nitric oxide (NO(X) = NO(2) + NO(3)) was measured with the Saville assay. Asymmetric dimethylarginine, an endogenous inhibitor of NO(X) synthase, was measured with liquid chromatography. RESULTS Initial brachial artery diameters were not significantly different among the groups studied (4.85 +/- 0.18 mm for AAA group, 4.82 +/- 0.17 mm for PAOD group, 4.68 +/- 0.20 mm for controls). ED and EI vasodilation was significantly less (P =.02 and.03, respectively) in the AAA group (-1.71 +/- 1.52 and 8.33 +/- 1.13, respectively) when compared with the controls (2.96 +/- 1.04 and 13.88 +/- 2.16, respectively). However, plasma NO(X) was significantly increased (P =.01) in the AAA group (7.86 +/- 0.85 micromol/L) as compared with both controls (5.13 +/- 0.63 micromol/L) and PAOD (4.85 +/- 0.46 micromol/L). Asymmetric dimethylarginine levels were decreased in the AAA group (0.34 +/- 0.05 micromol/L) as compared with the PAOD group (0.46 +/- 0.09 micromol/L). No correlation existed between aneurysm size and ED or EI vasodilation or plasma NO(X). CONCLUSION This study is the first to document a divergence between ED and EI vasoreactivity and systemic NO metabolites in patients with AAAs. It is speculated that a dysfunctional vessel wall response, rather than a lack of NO, may be important in the pathogenesis of AAAs.
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Affiliation(s)
- Brian S Knipp
- Jobst Vascular Research Laboratories, Section of Vascular Surgery, Department of Surgery, Division of Cardiology, University of Michigan Medical Center, Ann Arbor 48109-0329, USA
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Flora HS, Woodhouse N, Robson S, Adiseshiah M. Micromovements at the Aortic Aneurysm Neck Measured During Open Surgery With Close-Range Photogrammetry: Implications for Aortic Endografts. J Endovasc Ther 2001. [DOI: 10.1583/1545-1550(2001)008<0511:mataan>2.0.co;2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Flora HS, Woodhouse N, Robson S, Adiseshiah M. Micromovements at the aortic aneurysm neck measured during open surgery with close-range photogrammetry: implications for aortic endografts. J Endovasc Ther 2001; 8:511-20. [PMID: 11718411 DOI: 10.1177/152660280100800514] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To describe the motion of abdominal aortic aneurysm (AAA) as a first step toward determining if stent-graft migration may be due to propulsive movements at the neck. METHOD In an initial laboratory validation test, a silicone AAA model was imaged with a stereo-pair configuration of calibrated digital cameras using retro-reflective and ink dot surface targets. This technique was then applied to 4 aneurysm necks imaged at open surgery. In each case the paired images were measured and analyzed to produce sequences of accurate three-dimensional (3-D) surface models of the anterior aspect of the aortic neck. Engineering techniques were used to visualize and identify differences between the generated surfaces, allowing changes in shape of the aortic wall to be determined. RESULTS The correlation between stereoscopic digital imaging with electronic caliper measurements of linear dimensions was accurate, irrespective of the type of surface targets used (r2 = 0.98). The AAA neck demonstrated complex 3-D movements that ranged from 1.0 to 1.5 mm in the radial direction to 0.6 to 1.0 mm along the longitudinal axis, with a 0.44 to 0.59-mm rotational component (p < 0.05). CONCLUSIONS This pilot study raises questions about the validity of accepted models of arterial wall movements and compliance in which rotation has not been described. The technique used to measure dynamic neck morphology appears promising as a means to further define the mechanical parameters of the human aorta, which may assist in designing stent-grafts.
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Affiliation(s)
- H S Flora
- Vascular/Endovascular Unit, University College London Hospitals NHS Trust, England, UK
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Ravhon R, Adam D, Zelmanovitch L. Validation of ultrasonic image boundary recognition in abdominal aortic aneurysm. IEEE TRANSACTIONS ON MEDICAL IMAGING 2001; 20:751-763. [PMID: 11513026 DOI: 10.1109/42.938243] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
An aneurysm of the abdominal aorta (AAA) is characterized by modified wall properties, and a balloon-like area usually filled by a thrombus. A rupture of an aortic aneurysm can be fatal, yet there is no way to accurately predict such an occurrence. The study of the wall and thrombus cross-sectional distension, due to a pressure wave, is important as a way of assessing the degradation of the mechanical properties of the vessel wall and the risk of a rupture. Echo ultrasound transverse cross-sectional imaging is used here to study the thrombus and the aortic wall distension, requiring their segmentation within the image. Polar coordinates are defined, and a search is performed for minimizing a cost function, which includes a description of the boundary (based on a limited series of sine and cosine functions) and information from the image intensity gradients along the radii. The method is based on filtering by a modified Canny-Deriche edge detector and then on minimization of an energy function based on five parts. Since echoes from blood in the lumen and the thrombus produce similar patterns and speckle noise, a modified version for identifying the lumen-thrombus border was developed. The method has been validated by various ways, including parameter sensitivity testing and comparison to the performance of an expert. It is robust enough to track the lumen and total arterial cross-sectional area changes during the cardiac cycle. In 34 patients where sequences of images were acquired, the border between the thrombus and the arterial wall was detected with errors less than 2%, while the lumen-thrombus border was detected with a mean error of 4%. Thus, a noninvasive measurement of the AAA cross-sectional area is presented, which has been validated and found to be accurate.
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Affiliation(s)
- R Ravhon
- Department of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa
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Thubrikar MJ, al-Soudi J, Robicsek F. Wall stress studies of abdominal aortic aneurysm in a clinical model. Ann Vasc Surg 2001; 15:355-66. [PMID: 11414088 DOI: 10.1007/s100160010080] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
To estimate when an abdominal aortic aneurysm (AAA) may rupture, it is necessary to understand the forces responsible for this event. We investigated the wall stresses in an AAA in a clinical model. Using CT scans of the AAA, the diameter and wall thickness were measured and the model of the aneurysm was created. The wall stresses were determined using a finite element analysis in which the aorta was considered isotropic with linear material properties and was loaded with a pressure of 120 mmHg. The AAA was eccentric with a length of 10.5 cm, a diameter of 2.5 to 5.9 cm, and a wall thickness of 1.0 to 2.0 mm. The aneurysm had specific areas of high stress. On the inner surface the highest stress was 0.4 N/mm2 and occurred along two circumferentially oriented belts--one at the bulb and the other just below. The stress was longitudinal at the anterior region of the bulb and circumferential elsewhere, suggesting that a rupture caused by this stress will result in a circumferential tear at the anterior portion of the bulb and a longitudinal tear elsewhere. In the mid-surface the highest stress was 0.37 N/mm2 and occurred at two locations: the posterior region of the bulb and anteriorly just below. The stress was circumferential, suggesting that the rupture caused by this stress will produce a longitudinal tear. The location and orientation of the maximum stress were influenced more by the tethering force than by the wall thickness, luminal pressure, or wall stiffness. In conclusion, the rupture of an AAA is most likely to occur on the inner surface at the bulb. Such analytical approaches could lead to a better understanding of the aneurysm rupture and may be instrumental in planning surgical interventions.
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Affiliation(s)
- M J Thubrikar
- Heineman Medical Research Laboratory, Carolinas Medical Center, 1000 Blythe Boulevard, Charlotte, NC 28203, USA.
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Midttun M. Blood flow rate in arteriovenous anastomoses: from the cradle to the grave. CLINICAL PHYSIOLOGY (OXFORD, ENGLAND) 2000; 20:360-5. [PMID: 10971547 DOI: 10.1046/j.1365-2281.2000.00270.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Blood flow rate was measured in the arteriovenous anastomoses (AVAs) in the cutaneous tissue of the pulp of the first toe in 15 children between 3 and 15 years old, and in the pulp of the thumb and the first toe in 16 adults between 27 and 93 years old (two subjects from each decade) by the heat-washout method. The examinations showed that AVA-blood flow rate decreased with increasing age, and the difference between children and adults was highly significant (P=0.001). Blood flow rate in the finger pulp was higher than in the toe pulp (P=0.025). No significant difference in blood flow rate was found in either thumb pulp or toe pulp between men and women.
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Affiliation(s)
- M Midttun
- Med. Fys. Institute, The Panum Institute, 3, Blegdamsvej, 2200 Copenhagen N, Denmark
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Makita S, Ohira A, Tachieda R, Itoh S, Moriai Y, Niinuma H, Nakamura M, Hiramori K. Dilation and reduced distensibility of carotid artery in patients with abdominal aortic aneurysms. Am Heart J 2000; 140:297-302. [PMID: 10925346 DOI: 10.1067/mhj.2000.108000] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND Although patients with abdominal aortic aneurysms (AAA) frequently have coexisting systemic atherosclerosis, the dilatative manifestation of AAA is the opposite of the occlusion characteristic of atherosclerotic disease. It has been suggested that this dilatative disease is caused by an alteration in connective tissue metabolism in systemic arterial wall. Such a condition might alter systemic arterial diameter and wall behavior. We investigated arterial characteristics in AAA patients, including morphologic changes and wall mechanics in the carotid artery. METHODS AND RESULTS Atherosclerotic intimal changes such as intima-media thickness (IMT), plaque formation, diameter, and wall elasticity of the carotid artery were determined ultrasonographically in patients with AAA (n = 102) and compared with age-matched patients with the atherosclerotic diseases arteriosclerosis obliterans (ASO, n = 115) and coronary artery disease (CAD, n = 123) and with age-matched healthy control patients (CTL, n = 45). Intimal disease in AAA was significantly milder than in ASO, at the same level as CAD, and more severe than in CTL. Although end-diastolic luminal diameters (mm) in AAA (7.05 +/- 1.08), ASO (6.74 +/- 0.18), and CAD (6.66 +/- 0.83) were significantly higher than in CTL (5.97 +/- 0.93), they were also excessively increased compared with the equivalent diameters seen in ASO (P <.01) and CAD (P <.01). Luminal distensibility (x 10(-6) cm(2). dyne(-1)) in AAA (0.83 +/- 0.48) was excessively decreased compared not only with CTL (1.70 +/- 1.11, P <.01) but also with ASO (1.12 +/- 0.47, P <.01) and CAD (1.18 +/- 0.59, P <. 01). These relations remained true when adjusted for blood pressure and luminal diameter. Intra-AAA group analysis showed that distensibility in ruptured cases (n = 14) was significantly lower than in nonruptured cases (n = 88) (0.58 +/- 0.24 vs 0.88 +/- 0.50, P <.05). CONCLUSIONS Excessive arterial dilation and reduced distensibility without severe intimal disease were found in the carotid arteries of patients with AAA. This suggests that these patients may be subject to systemic arterial alterations, including structural and functional abnormalities.
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Affiliation(s)
- S Makita
- Department of Internal Medicine II, Iwate Medical University, Moriaka, Japan.
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Gerdes LU, Lindholt JS, Vammen S, Henneberg EW, Fasting H. Apolipoprotein E genotype is associated with differential expansion rates of small abdominal aortic aneurysms. Br J Surg 2000; 87:760-5. [PMID: 10848855 DOI: 10.1046/j.1365-2168.2000.01486.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The common polymorphism of the apolipoprotein E (APOE) gene is associated with differential risk of atherosclerosis; the gene could be a candidate gene in abdominal aortic aneurysms (AAA). METHODS APOE genotypes were determined in 57 men aged 65-73 years with a small AAA (30-50 mm). The patients were included in a population ultrasonographic screening programme and were followed with at least two examinations during an interval of 2-4.5 years. The AAA expansion rates in patients with four different APOE genotypes were studied, with adjustment for initial AAA size and smoking. RESULTS APOE genotype was a significant determinant of AAA expansion rate (P = 0.001). The adjusted mean (95 per cent confidence interval) rate was 2.1 (1.7-2.6) mm/year in 31 men with genotype E3E3, 1.3 (0.7-1.9) mm/year in 17 men with E3E4, 3.1 (2.0-4. 1) mm/year in six men with E2E3 and 4.2 (2.7-5.6) mm/year in three men with E2E4. The mean expansion rate was 2.2 (1.5-2.8) mm/year in non-smokers and 3.0 (2.5-3.6) mm/year in smokers (P = 0.014). CONCLUSION APOE genotype seems to influence AAA expansion rate, but the effects of the individual genotypes, in particular E3E3 and E3E4, are contradictory when compared with the effects of the genotypes on risk of atherosclerosis.
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Affiliation(s)
- L U Gerdes
- Department of Clinical Biochemistry, Aarhus University Hospital, Denmark
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Inci S, Spetzler RF. Intracranial aneurysms and arterial hypertension: a review and hypothesis. SURGICAL NEUROLOGY 2000; 53:530-40; discussion 540-2. [PMID: 10940419 DOI: 10.1016/s0090-3019(00)00244-5] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Intracranial aneurysms and systemic arterial hypertension coexist in a high percentage of patients. The relationship between intracranial aneurysms and hypertension is poorly defined. METHODS Therefore, we reviewed the role of hypertension in the pathogenesis of saccular aneurysms as previously reported in clinical, experimental, and autopsy studies. RESULTS Among 24 relevant clinical and/or autopsy studies, the mean incidence of pre-existing hypertension was 43.5% in aneurysm patients compared to 24.4% in the normal population. Although definitive evidence is lacking, data from multiple types of investigations indicate that systemic arterial hypertension creates a greater risk for the development of intracranial aneurysms than previously believed. The underlying pathophysiological mechanism(s) are also poorly defined. CONCLUSIONS We propose a unifying hypothesis: Endothelial injury, occlusion of the vasa vasorum, and disruption of the synthesis of collagen and elastin are likely the most important factors in initiating the development of aneurysms. Chronic hypertension potentially affects all of these factors. Consequently, chronic hypertension may cause intimal thickening, necrosis of the tunica media, changes in the compositional matrix, and degeneration of the internal elastic lamina to develop in the arterial wall. These structural changes could cause a focal weakening in the arterial wall with resultant bulging. This theory accounts for the high incidence of intracranial aneurysms in the absence of any known associated hereditary or connective-tissue disease. Nor does it exclude the possibility of other etiological factors. From the perspective of prevention, however, it offers clear opportunities for prophylaxis.
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Affiliation(s)
- S Inci
- Department of Neurosurgery, University of Hacettepe School of Medicine, Ankara, Turkey
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