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Huang D, Wanchu R, Cho M, Leon L, Ganti L. Emergency department point-of-care ultrasound diagnosis of active bleeding into the intraluminal thrombus of an abdominal aortic aneurysm. Radiol Case Rep 2023; 18:2116-2120. [PMID: 37089970 PMCID: PMC10113758 DOI: 10.1016/j.radcr.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 04/25/2023] Open
Abstract
Rupture of an abdominal aortic aneurysm (AAA) is an immediately life-threatening phenomenon with substantial mortality. Although most AAAs are asymptomatic, an impending AAA rupture can be heralded by nonspecific symptoms and imaging findings on CT and point-of-care ultrasound (POCUS). In this report, we present a case of an 81-year-old male with an atypical presentation of an AAA with novel sonographic findings of imminent rupture on POCUS with Doppler that prompted successful emergent intervention. In the emergency department, imaging findings on aortic POCUS and CT imaging with angiography can facilitate assessment for impending aortic rupture, which can expedite appropriate disposition and potentially life-saving intervention.
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2
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Parenti VG, Vijay K, Maroules CD, Majdalany BS, Koweek LM, Khaja MS, Ghoshhajra BB, Agarwal PP, Contrella BN, Keefe NA, Lo BM, Malik SB, Surasi DS, Waite K, Williamson EE, Abbara S, Dill KE. ACR Appropriateness Criteria® Workup of Noncerebral Systemic Arterial Embolic Source. J Am Coll Radiol 2023; 20:S285-S300. [PMID: 37236749 DOI: 10.1016/j.jacr.2023.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 02/27/2023] [Indexed: 05/28/2023]
Abstract
Noncerebral systemic arterial embolism, which can originate from cardiac and noncardiac sources, is an important cause of patient morbidity and mortality. When an embolic source dislodges, the resulting embolus can occlude a variety of peripheral and visceral arteries causing ischemia. Characteristic locations for noncerebral arterial occlusion include the upper extremities, abdominal viscera, and lower extremities. Ischemia in these regions can progress to tissue infarction resulting in limb amputation, bowel resection, or nephrectomy. Determining the source of arterial embolism is essential in order to direct treatment decisions. This document reviews the appropriateness category of various imaging procedures available to determine the source of the arterial embolism. The variants included in this document are known arterial occlusion in the upper extremity, lower extremity, mesentery, kidneys, and multiorgan distribution that are suspected to be of embolic etiology. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
- Vincent G Parenti
- Research Author, University of Texas Southwestern Medical Center, Dallas, Texas
| | | | | | | | - Lynne M Koweek
- Panel Chair, Duke University Medical Center, Durham, North Carolina
| | | | | | | | | | - Nicole A Keefe
- University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Bruce M Lo
- Sentara Norfolk General Hospital/Eastern Virginia Medical School, Norfolk, Virginia; American College of Emergency Physicians
| | - Sachin B Malik
- VA Palo Alto Health Care System, Palo Alto, California and Stanford University, Stanford, California
| | - Devaki Shilpa Surasi
- The University of Texas MD Anderson Cancer Center, Houston, Texas; Commission on Nuclear Medicine and Molecular Imaging
| | - Kathleen Waite
- Duke University Medical Center, Durham, North Carolina, Primary care physician
| | - Eric E Williamson
- Mayo Clinic, Rochester, Minnesota; Society of Cardiovascular Computed Tomography
| | - Suhny Abbara
- Specialty Chair, UT Southwestern Medical Center, Dallas, Texas
| | - Karin E Dill
- Specialty Chair, Emory University Hospital, Atlanta, Georgia
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3
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Bontekoe J, Matsumura J, Liu B. Thrombosis in the pathogenesis of abdominal aortic aneurysm. JVS Vasc Sci 2023; 4:100106. [PMID: 37564632 PMCID: PMC10410173 DOI: 10.1016/j.jvssci.2023.100106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 03/23/2023] [Indexed: 08/12/2023] Open
Abstract
Background Abdominal aortic aneurysms (AAAs) are a relatively common vascular pathology of the elderly with high morbidity potential. Irreversible degeneration of the aortic wall leads to lethal rupture if left untreated. Nearly all AAAs contain intraluminal thrombus (ILT) to a varying degree, yet the mechanisms explaining how thrombosis is disturbed in AAA are relatively unknown. This review examined the thrombotic complications associated with AAA, the impact of thrombosis on AAA surgical outcomes and AAA pathogenesis, and the use of antithrombotic therapy in the management of this disease. Methods A literature search of the PubMed database was conducted using relevant keywords related to thrombosis and AAAs. Results Thrombotic complications are relatively infrequent in AAA yet carry significant morbidity risks. The ILT can impact endovascular aneurysm repair by limiting anatomic suitability and influence the risk of endoleaks. Many of the pathologic mechanisms involved in AAA development, including hemodynamics, inflammation, oxidative stress, and aortic wall remodeling, contain pathways that interact with thrombosis. Conversely, the ILT can also be a source of biochemical stress and exacerbate these aneurysmal processes. In animal AAA models, antithrombotic therapies have shown favorable results in preventing and stabilizing AAA. Antiplatelet agents may be beneficial for reducing risks of major adverse cardiovascular events in AAA patients; however, neither antiplatelet nor anticoagulation is currently used solely for the management of AAA. Conclusions Thrombosis and ILT may have detrimental effects on AAA growth, rupture risk, and patient outcomes, yet there is limited understanding of the pathologic thrombotic mechanisms in aneurysmal disease at the molecular level. Preventing ILT using platelet and coagulation inhibitors may be a reasonable theoretical target for aneurysm progression and stability; however, the practical benefits of current antithrombotic therapies in AAA are unclear. Further research is needed to demonstrate the extent to which thrombosis impacts AAA pathogenesis and to develop novel pharmacologic strategies for the medical management of this disease.
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Affiliation(s)
- Jack Bontekoe
- Division of Vascular Surgery, Department of Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI
| | - Jon Matsumura
- Division of Vascular Surgery, Department of Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI
| | - Bo Liu
- Division of Vascular Surgery, Department of Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI
- Department of Cellular and Regenerative Biology, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI
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4
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Bittner T, Babbush C, Vincent AC, Rokkam V. Spinal cord infarction resulting from intramural haematoma of the thoracic aorta. BMJ Case Rep 2023; 16:e254173. [PMID: 37041042 PMCID: PMC10105982 DOI: 10.1136/bcr-2022-254173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023] Open
Abstract
We present the case of a female patient in her 60s with multiple medical comorbidities who presented to the emergency department with sudden-onset tearing chest, back and abdominal pain in the setting of a hypertensive emergency. Initial CT-angiography demonstrated mild-diffuse thickening of thoracic and abdominal aorta without signs of intramural haematoma or dissection. The patient was subsequently admitted and medically managed. In the days following admission, the patient developed a small bowel obstruction and neurological deficits. Repeat imaging demonstrated an intramural haematoma extending from left subclavian artery to the diaphragm resulting in foci of spinal cord infarction. Instances of spinal cord infarction secondary to aortic intramural haematoma are rare, with a minority of cases reported as of 2020. This case report highlights a non-classic patient presentation of an intramural haematoma, shedding light onto possible clinical outcomes, treatment options and important risk factors.
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Affiliation(s)
- Tyler Bittner
- Department of Medicine, The University of Arizona College of Medicine Tucson, Tucson, Arizona, USA
| | - Connor Babbush
- Department of Medicine, The University of Arizona College of Medicine Tucson, Tucson, Arizona, USA
| | - Ashley Chey Vincent
- Department of Medicine, The University of Arizona College of Medicine Tucson, Tucson, Arizona, USA
| | - Venkata Rokkam
- Department of Medicine, The University of Arizona College of Medicine Tucson, Tucson, Arizona, USA
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5
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Correlation Between Proteolytic Activity and Abdominal Aortic Aneurysm Wall Morphology with Intraluminal Thrombus Volume. Ann Vasc Surg 2022; 87:487-494. [PMID: 35779804 DOI: 10.1016/j.avsg.2022.05.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/19/2022] [Accepted: 05/26/2022] [Indexed: 11/24/2022]
Abstract
BACKGROUND The aim of this study was to examine the influence of intraluminal thrombus (ILT) volume on the level of proteolytic activity and the content of abdominal aortic aneurysm (AAA) wall. METHODS The research was designed as a cross-sectional study at the Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia in the period from April 2017 to February 2018. During this period, a total of 155 patients with asymptomatic AAA underwent open surgical treatment and 50 were included in the study based on inclusion and exclusion criteria. Before surgery, patients included in the study were examined by MRI. During the operation, samples of ILT and AAA wall were taken for biochemical analysis. RESULTS A statistically significant correlation was found between the volume of the ILT and largest AAA diameter (ρ = 0.56; P < 0.001). The correlation of the ILT volume on the anterior wall and the concentration of MMP-9, MMP-2 and NE/ELA in the wall did not find statistical significance. Also, no statistically significant association was found between the volume of ILT and the concentration of ECM proteins (collagen type 3, elastin, proteoglycan) in the corresponding part of the wall. The association of ILT volume with MDA was also of no statistical significance. There was a positive statistical significance found in correlation of volume of ILT and catalase activity in the wall of AAA (ρ = 0.28, P = 0.049). CONCLUSIONS The volume of ILT in the aneurysmal sac seemed not to affect the level of proteolytic activity and the content of the aneurysm wall. However, a positive correlation was found between the ILT and the catalase activity. The effect of ILT on the aneurysm wall and its role in the progression of aneurysmal disease should be examined in future studies.
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6
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Mangarova DB, Bertalan G, Jordan J, Brangsch J, Kader A, Möckel J, Adams LC, Sack I, Taupitz M, Hamm B, Braun J, Makowski MR. Microscopic multifrequency magnetic resonance elastography of ex vivo abdominal aortic aneurysms for extracellular matrix imaging in a mouse model. Acta Biomater 2022; 140:389-397. [PMID: 34818577 DOI: 10.1016/j.actbio.2021.11.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/16/2021] [Accepted: 11/17/2021] [Indexed: 11/27/2022]
Abstract
An abdominal aortic aneurysm (AAA) is a permanent dilatation of the abdominal aorta, usually accompanied by thrombus formation. The current clinical imaging modalities cannot reliably visualize the thrombus composition. Remodeling of the extracellular matrix (ECM) during AAA development leads to stiffness changes, providing a potential imaging marker. 14 apolipoprotein E-deficient mice underwent surgery for angiotensin II-loaded osmotic minipump implantation. 4 weeks post-op, 5 animals developed an AAA. The aneurysm was imaged ex vivo by microscopic multifrequency magnetic resonance elastography (µMMRE) with an in-plane resolution of 40 microns. Experiments were performed on a 7-Tesla preclinical magnetic resonance imaging scanner with drive frequencies between 1000 Hz and 1400 Hz. Shear wave speed (SWS) maps indicating stiffness were computed based on tomoelastography multifrequency inversion. As control, the aortas of 5 C57BL/6J mice were examined with the same imaging protocol. The regional variation of SWS in the thrombus ranging from 0.44 ± 0.07 to 1.20 ± 0.31 m/s was correlated fairly strong with regional histology-quantified ECM accumulation (R2 = 0.79). Our results suggest that stiffness changes in aneurysmal thrombus reflect ECM remodeling, which is critical for AAA risk assessment. In the future, µMMRE could be used for a mechanics-based clinical characterization of AAAs in patients. STATEMENT OF SIGNIFICANCE: To our knowledge, this is the first study mapping the stiffness of abdominal aortic aneurysms with microscopic resolution of 40 µm. Our work revealed that stiffness critically changes due to extracellular matrix (ECM) remodeling in the aneurysmal thrombus. We were able to image various levels of ECM remodeling in the aneurysm reflected in distinct shear wave speed patterns with a strong correlation to regional histology-quantified ECM accumulation. The generated results are significant for the application of microscopic multifrequency magnetic resonance elastography for quantification of pathological remodeling of the ECM and may be of great interest for detailed characterization of AAAs in patients.
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Affiliation(s)
- Dilyana B Mangarova
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany; Department of Veterinary Medicine, Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, Building 12, Berlin 4163, Germany.
| | - Gergely Bertalan
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Jakob Jordan
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Julia Brangsch
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Avan Kader
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany; Department of Biology, Chemistry and Pharmacy, Institute of Biology, Freie Universität Berlin, Königin-Luise-Str. 1-3, Berlin 14195, Germany.
| | - Jana Möckel
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Lisa C Adams
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Matthias Taupitz
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Bernd Hamm
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany.
| | - Jürgen Braun
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany; Institute for Medical Informatics, Charité - Universitätsmedizin Berlin, Berlin, Germany, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Hindenburgdamm 30, Berlin 12200, Germany.
| | - Marcus R Makowski
- Department of Radiology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, Berlin 10117, Germany; Department of Diagnostic and Interventional Radiology, Technical University of Munich, Ismaninger Str. 22, Munich 81675, Germany.
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7
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Stoecker JB, Eddinger KC, Pouch AM, Glaser JD, Foley PJI, Wang GJ, Kalapatapu VR, Jackson BM. The Hyperattenuating Crescent Sign Is Not Necessarily a Sign of Impending Aortic Aneurysm Rupture. Ann Vasc Surg 2021; 82:240-248. [PMID: 34788704 PMCID: PMC9154016 DOI: 10.1016/j.avsg.2021.10.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/01/2021] [Accepted: 10/10/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND The "crescent sign" is a hyperattenuating crescent-shaped region on CT within the mural thrombus or wall of an aortic aneurysm. Although it has previously been associated with aneurysm instability or impending rupture, the literature is largely based on retrospective analyses of urgently repaired aneurysms. We strove to more rigorously assess the association between an isolated "crescent sign" and risk of impending aortic rupture. METHODS Patients were identified by querying a single health system PACS database for radiology reports noting a crescent sign. Adult patients with a CT demonstrating a descending thoracic, thoracoabdominal, or abdominal aortic aneurysm and "crescent sign" between 2004 and 2019 were included, with exclusion of those showing definitive signs of aortic rupture on imaging. RESULTS A total of 82 patients were identified. Aneurysm size was 7.1 ± 2.0 cm. Thirty patients had emergent or urgent repairs during their index admission (37%), 19 had elective repairs at a later date (23%), and 33 patients had no intervention due to either patient choice or prohibitive medical comorbidities (40%). Patients without intervention had a median follow up of 275 days before death or loss to follow up. In patients undergoing elective intervention, 6,968 patient-days elapsed between presentation and repair, with zero episodes of acute rupture (median 105 days). Patients undergoing elective repair had smaller aneurysms compared to those who underwent emergent/urgent repair (6.2 ± 1.3 vs. 7.7 ± 2.1 cm, P = 0.008). No surgical candidate with an aneurysm smaller than 8 cm ruptured. There were 31 patients with previous axial imaging within 2 years prior to presentation with a "crescent sign," with mean aneurysm growth rate of 0.85 ± 0.62 cm per 6 months [median 0.65, range 0-2.6]. Those with aneurysms sized below 5.5 cm displayed decreased aneurysm growth compared to patients with aneurysm's sized 5.5-6.5 cm or patients with aneurysms greater than 6.5 cm (0.12 vs. 0.64 vs. 1.16 cm per 6 months, P= 0.002). CONCLUSIONS The finding of an isolated radiographic "crescent sign" without other signs of definitive aortic rupture (i.e., hemothorax, aortic wall disruption, retroperitoneal bleeding) is not necessarily an indicator of impending aortic rupture, but may be found in the setting of rapid aneurysm growth. Many factors, including other associated radiographic findings, aneurysm size and growth rate, and patient symptomatology, should guide aneurysm management in these patients. We found that patients with minimal symptoms, aneurysm sizes below 6.5 cm, and no further imaging findings of aneurysm instability, such as periaortic fat stranding, can be successfully managed with elective intervention after optimization of comorbid factors with no evidence of adverse outcomes.
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Affiliation(s)
- Jordan B Stoecker
- Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA.
| | - Kevin C Eddinger
- Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Alison M Pouch
- Department of Radiology, University of Pennsylvania, Philadelphia, PA
| | - Julia D Glaser
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Paul J Iii Foley
- Department of Surgery, Doylestown Health Vascular Surgery, Doylestown, PA
| | - Grace J Wang
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Venkat R Kalapatapu
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
| | - Benjamin M Jackson
- Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
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8
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Ono R, Kajiyama T, Kobayashi Y. Anechoic crescent sign. BMJ Case Rep 2021; 14:14/2/e241358. [PMID: 33526541 PMCID: PMC7853005 DOI: 10.1136/bcr-2020-241358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Ryohei Ono
- Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Takatsugu Kajiyama
- Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Yoshio Kobayashi
- Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Chiba, Japan
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9
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Collard M, Sutphin PD, Kalva SP, Majdalany BS, Collins JD, Eldrup-Jorgensen J, Francois CJ, Ganguli S, Gunn AJ, Kendi AT, Khaja MS, Obara P, Reis SP, Vijay K, Dill KE. ACR Appropriateness Criteria ® Abdominal Aortic Aneurysm Follow-up (Without Repair). J Am Coll Radiol 2020; 16:S2-S6. [PMID: 31054747 DOI: 10.1016/j.jacr.2019.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 02/07/2019] [Indexed: 10/26/2022]
Abstract
Abdominal aortic aneurysm (AAA) is defined as aneurysmal dilation of the abdominal aorta to 3 cm or greater. A high degree of morbidity and mortality is associated with AAA rupture, and imaging surveillance plays an essential role in mitigating the risk of rupture. Aneurysm size and growth rate are factors associated with the risk of rupture, thus surveillance imaging studies must be accurate and reproducible to characterize aneurysm size. Ultrasound, CT angiography, and MR angiography provide an accurate and reproducible assessment of size, while radiographs and aortography provide limited evaluation. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
| | - Michael Collard
- Research Author, UT Southwestern Medical Center, Dallas, Texas
| | | | | | - Bill S Majdalany
- Panel Vice-Chair, University of Michigan Health System, Ann Arbor, Michigan
| | | | - Jens Eldrup-Jorgensen
- Tufts University School of Medicine, Boston, Massachusetts; Society for Vascular Surgery
| | | | | | - Andrew J Gunn
- University of Alabama at Birmingham, Birmingham, Alabama
| | | | | | - Piotr Obara
- Loyola University Medical Center, Maywood, Illinois
| | | | | | - Karin E Dill
- Specialty Chair, UMass Memorial Medical Center, Worcester, Massachusetts
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10
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Jayendiran R, Condemi F, Campisi S, Viallon M, Croisille P, Avril S. Computational prediction of hemodynamical and biomechanical alterations induced by aneurysm dilatation in patient-specific ascending thoracic aortas. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2020; 36:e3326. [PMID: 32087044 DOI: 10.1002/cnm.3326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 02/15/2020] [Indexed: 06/10/2023]
Abstract
The aim of the present work is to propose a robust computational framework combining computational fluid dynamics (CFD) and 4D flow MRI to predict the progressive changes in hemodynamics and wall rupture index (RPI) induced by aortic morphological evolutions in patients harboring ascending thoracic aortic aneurysms (ATAAs). An analytical equation has been proposed to predict the aneurysm progression based on age, sex, and body surface area. Parameters such as helicity, wall shear stress (WSS), time-averaged WSS, oscillatory shear index, relative residence time, and viscosity were evaluated for two patients at different stages of aneurysm growth, and compared with age-sex-matched healthy subjects. The study shows that evolution of hemodynamics and RPI, despite being very slow in ATAAs, is strongly affected by morphological alterations and, in turn could impact biomechanical factors and aortic mechanobiology. An aspect of the current work is that the patient-specific 4D MRI data sets were obtained with a follow-up of 1 year and the measured time-averaged velocity maps and flow eccentricity were compared with the CFD simulation for validation. The computational framework presented here is capable of capturing the blood flow patterns and the hemodynamic descriptors during the various stages of aneurysm growth. Further investigations will be conducted in order to verify these results on a larger cohort of patients and with long follow-up times to finally elucidate the link between deranged hemodynamics, AA geometry, and wall mechanical properties in ATAAs.
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Affiliation(s)
- Raja Jayendiran
- Mines Saint-Etienne, Université de Lyon, INSERM, U1059, SAINBIOSE, Saint-Etienne F-42023, France
| | | | - Salvatore Campisi
- Department of Cardiovascular Surgery, University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Magalie Viallon
- UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, Université de Lyon, Saint-Etienne, France
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Pierre Croisille
- UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, Université de Lyon, Saint-Etienne, France
- Department of Radiology, University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Stéphane Avril
- Mines Saint-Etienne, Université de Lyon, INSERM, U1059, SAINBIOSE, Saint-Etienne F-42023, France
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11
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Magnetic resonance imaging assessment of proteolytic enzyme concentrations and biologic properties of intraluminal thrombus in abdominal aortic aneurysms. J Vasc Surg 2020; 72:1025-1034. [PMID: 32067878 DOI: 10.1016/j.jvs.2019.11.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 11/04/2019] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The aim of the study was to determine whether magnetic resonance imaging (MRI) can be used in assessment of biologic activity of intraluminal thrombus (ILT) and proteolytic processes of the abdominal aortic aneurysm wall. METHODS Using MRI, 50 patients with asymptomatic infrarenal abdominal aortic aneurysm were analyzed at the maximum aneurysm diameter on T1-weighted images in the arterial phase after administration of contrast material. Relative ILT signal intensity (SI) was determined as the ratio between ILT SI and psoas muscle SI. During surgery, the full thickness of the ILT and the adjacent part of the aneurysm wall were harvested at the maximal diameter for biochemical analysis. The concentrations of matrix metalloproteinase 9 and neutrophil elastase (NE/ELA) were analyzed in harvested thrombi, and the concentrations of collagen type III, elastin, and proteoglycans were analyzed in harvested aneurysm walls. RESULTS A significant positive correlation was found between the NE/ELA concentration of the ILT and the relative SI (ρ = 0.309; P = .029). Furthermore, a negative correlation was observed between the elastin content of the aneurysm wall and the relative SI (ρ = -0.300; P = .034). No correlations were found between relative SI and concentration of matrix metalloproteinase 9, NE/ELA, collagen type III, or proteoglycan 4 in the aneurysm wall. CONCLUSIONS These findings indicate a potential novel use of MRI in prediction of thrombus proteolytic enzyme concentrations and the extracellular matrix content of the aneurysm wall, thus providing additional information for the risk of potential aneurysm rupture.
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12
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Goldstein LN, Wells M. Point-of-care Ultrasound Trumps Computed Tomography in a Case of Abdominal Aortic Aneurysm Assessment. Cureus 2019; 11:e5989. [PMID: 31807377 PMCID: PMC6876902 DOI: 10.7759/cureus.5989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Patients who present to the emergency department (ED) with aortic emergencies can be some of the highest acuity patients that we manage. Ultrasonography performed at the bedside is traditionally considered to be a screening test that is especially useful in the unstable patient. Computed tomography (CT) with angiography is the imaging modality of choice to confirm the diagnosis and plan the management of abdominal aortic aneurysm (AAA), as an ultrasound is generally thought not to provide the clinician with sufficient anatomical information. We present a case of a patient with an abdominal aortic aneurysm where evidence obtained from the ultrasound provided more useful information regarding aneurysm structure and stability than did CT.
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Affiliation(s)
- Lara N Goldstein
- Emergency Medicine, University of the Witwatersrand, Johannesburg, ZAF
| | - Mike Wells
- Emergency Medicine, University of the Witwatersrand, Johannesburg, ZAF
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13
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Shelton CC, Tyagi SC, Sanampudi S, Issa MM, Raissi D, Lowry CM, Winkler MA. Congenital intravascular abdominal aortic band initially thought to be a metallic foreign body: Characterization using microanatomical CT reconstruction technique. Radiol Case Rep 2019; 14:1127-1131. [PMID: 31360273 PMCID: PMC6637249 DOI: 10.1016/j.radcr.2019.06.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 06/12/2019] [Accepted: 06/29/2019] [Indexed: 11/25/2022] Open
Abstract
We present a patient with the initial misdiagnosis of a metallic foreign body in the abdominal aorta. Computed tomographic angiography utilizing microanatomical reconstruction technique revealed the structure to instead be a partially calcified abdominal aortic congenital fibrous band. Most congenital fibrous bands spanning the aortic lumen are proximal within the aorta and are thought to be supportive structures of the aortic valve leaflets. Congenital fibrous bands distal to the sinotubular junction are quite rare.
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Affiliation(s)
- Charles C Shelton
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
| | - Samuel C Tyagi
- Department of Surgery, Division of Vascular Surgery, University of Kentucky Vascular Medicine Clinic, Lexington, KY, USA
| | - Sreeja Sanampudi
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
| | - Mohamed M Issa
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
| | - Driss Raissi
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
| | - Conor M Lowry
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
| | - Michael A Winkler
- Department of Radiology, Gill Heart Institute, University of Kentucky Chandler Medical Center, Lexington, KY, USA
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14
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Leach J, Kao E, Zhu C, Saloner D, Hope MD. On the relative impact of intraluminal thrombus heterogeneity on abdominal aortic aneurysm mechanics. J Biomech Eng 2019; 141:2737715. [PMID: 31253989 DOI: 10.1115/1.4044143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Indexed: 01/31/2023]
Abstract
Intraluminal thrombus (ILT) is present in the majority of abdominal aortic aneurysms (AAA) of a size warranting consideration for surgical or endovascular intervention. The rupture risk of AAAs is thought to be related to the balance of vessel wall strength and the mechanical stress caused by systemic blood pressure. Previous finite element analyses of AAAs have shown that ILT can reduce and homogenize aneurysm wall stress. These works have largely considered ILT to be homogeneous in mechanical character or have idealized a stiffness distribution through the thrombus thickness. In this work, we use MRI to delineate the heterogeneous composition of ILT in 7 AAAs and perform patient-specific finite element analysis under multiple conditions of ILT layer stiffness disparity. We find that explicit incorporation of ILT heterogeneity in the finite element analysis is unlikely to substantially alter major stress analysis predictions regarding aneurysm rupture risk in comparison to models assuming a homogenous thrombus, provided that the maximal ILT stiffness is the same between models. Our results also show that under a homogeneous ILT assumption, the choice of ILT stiffness from values common in the literature can result in significantly larger variations in stress predictions compared to the effects of thrombus heterogeneity.
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Affiliation(s)
- Joseph Leach
- University of California, San Francisco, Department of Radiology and Biomedical Imaging, 513 Parnassus Ave, Suite S-261, Box 0628, San Francisco, CA 94143
| | - Evan Kao
- University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA 94143
| | - Chengcheng Zhu
- University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA 94143
| | - David Saloner
- University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA 94143
| | - Michael D Hope
- University of California, San Francisco, Department of Radiology and Biomedical Imaging, San Francisco, CA 94143
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15
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Cameron SJ, Russell HM, Owens AP. Antithrombotic therapy in abdominal aortic aneurysm: beneficial or detrimental? Blood 2018; 132:2619-2628. [PMID: 30228233 PMCID: PMC6302498 DOI: 10.1182/blood-2017-08-743237] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 09/10/2018] [Indexed: 12/13/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is a degenerative vascular pathology resulting in significant morbidity and mortality in older adults due to rupture and sudden death. Despite 150 000 new cases and nearly 15 000 deaths annually, the only approved treatment of AAA is surgical or endovascular intervention when the risk for aortic rupture is increased. The goal of the scientific community is to develop novel pharmaceutical treatment strategies to reduce the need for surgical intervention. Because most clinically relevant AAAs contain a complex structure of fibrin, inflammatory cells, platelets, and red blood cells in the aneurysmal sac known as an intraluminal thrombus (ILT), antithrombotic therapies have emerged as potential pharmaceutical agents for the treatment of AAA progression. However, the efficacy of these treatments has not been shown, and the effects of shrinking the ILT may be as detrimental as they are beneficial. This review discusses the prospect of anticoagulant and antiplatelet (termed collectively as antithrombotic) therapies in AAA. Herein, we discuss the role of the coagulation cascade and platelet activation in human and animal models of AAA, the composition of ILT in AAA, a possible role of the ILT in aneurysm stabilization, and the implications of antithrombotic drugs in AAA treatment.
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Affiliation(s)
- Scott J Cameron
- Department of Medicine (Cardiology) and
- Department of Surgery (Cardiac Surgery), University of Rochester School of Medicine, Rochester, NY; and
| | - Hannah M Russell
- Division of Cardiovascular Health and Disease and
- Pathobiology and Molecular Medicine, Department of Internal Medicine, The University of Cincinnati College of Medicine, Cincinnati, OH
| | - A Phillip Owens
- Division of Cardiovascular Health and Disease and
- Pathobiology and Molecular Medicine, Department of Internal Medicine, The University of Cincinnati College of Medicine, Cincinnati, OH
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16
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Fluid-structure interaction (FSI) analysis of stent-graft for aortic endovascular aneurysm repair (EVAR): Material and structural considerations. J Mech Behav Biomed Mater 2018; 87:95-110. [DOI: 10.1016/j.jmbbm.2018.07.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/10/2018] [Accepted: 07/12/2018] [Indexed: 01/07/2023]
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17
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Anastasiadou C, Giannakakis S, Papapetrou A, Galyfos G, Papacharalampous G, Maltezos C. Late Rupture of a Totally Thrombosed Abdominal Aortic Aneurysm: A Case Report and Literature Review. Ann Vasc Surg 2018; 46:368.e5-368.e8. [DOI: 10.1016/j.avsg.2017.07.043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 10/18/2022]
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18
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Jansen CHP, Brangsch J, Reimann C, Adams L, Hamm B, Botnar RM, Makowski MR. In Vivo High-Frequency Ultrasound for the Characterization of Thrombi Associated with Aortic Aneurysms in an Experimental Mouse Model. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:2882-2890. [PMID: 28965722 DOI: 10.1016/j.ultrasmedbio.2017.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/07/2017] [Accepted: 08/09/2017] [Indexed: 06/07/2023]
Abstract
The development of abdominal aortic aneurysm (AAA) associated thrombi plays an important role during the onset and progression of AAAs. The aim of this study was to evaluate the potential of high-frequency ultrasound for characterization of AAA associated thrombi in an apolipoprotein-E-deficient mouse-model. Ultrasound measurements were performed using a high-resolution ultrasound system (Vevo770, FUJIFILM VisualSonics, Inc., Toronto, ON, Canada) with a 30 MHz linear-array transducer (RMV707 B). Magnetic resonance imaging with a 3 Tesla scanner (Achieva MR system, Philips Healthcare, Best, The Netherlands) and a single-loop microscopy coil was performed as a reference standard. All stages of aneurysm development were evaluated by histologic analyses. The "signal-thrombus-matrix" to "signal-blood" ratio on high-frequency ultrasound measurements showed a strong correlation (R2 = 0.81, p <0.05) with the state of extracellular matrix remodeling. Furthermore, size measurements derived from the high-frequency ultrasound correlated well with magnetic resonance imaging and histology. This study demonstrated that high-frequency ultrasound enables the reliable in vivo quantification of extracellular matrix remodeling at various stages of thrombus development, based on the thrombus echogenicity.
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Affiliation(s)
| | | | | | - Lisa Adams
- Department of Radiology, Charité, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité, Berlin, Germany
| | - Rene M Botnar
- Division of Imaging Sciences, King's College London, London, United Kingdom; BHF Centre of Excellence, King's College London, London, United Kingdom; Cardioascular Division, King's College London, London, United Kingdom; Wellcome Trust and EPSRC Medical Engineering Center, King's College London, London, United Kingdom; NIHR Biomedical Research Centre, King's College London, London, United Kingdom
| | - Marcus R Makowski
- Division of Imaging Sciences, King's College London, London, United Kingdom; Department of Radiology, Charité, Berlin, Germany
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19
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Piacentino F, Fontana F, Micieli C, Angeretti MG, Cardim LN, Coppola A, Molinelli V, Piffaretti G, Novario R, Fugazzola C. Nonenhanced MRI Planning for Endovascular Repair of Abdominal Aortic Aneurysms: Comparison With Contrast-Enhanced CT Angiography. Vasc Endovascular Surg 2017; 52:39-45. [PMID: 29162027 DOI: 10.1177/1538574417740508] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND To assess whether noncontrast-enhanced magnetic resonance imaging (NC-MRI) is an alternative to contrast-enhanced computed tomography angiography (CTA) for aortoiliac measurements before endovascular abdominal aortic aneurysm repair (EVAR). METHODS This study encompasses 30 patients admitted for elective EVAR (27 men and 3 women). Two expert readers (vascular radiologist and vascular surgeon) reviewed CTA images in consensus and chose the proper endograft for each patient. Subsequently, a vascular radiologist and a resident radiologist (observer 1 and 2) reviewed CTA and NC-MRI examinations in a double-blind way and completed standard measurements. The interobserver and intermodality agreement was calculated by intraclass correlation coefficients (ICCs). Furthermore, the correlation between the endograft size chosen by the first pair and the second pair of observers was evaluated. RESULTS Concerning all measurements, no significant difference was found. Both CTA and NC-MRI angiographic measurements showed strong correlation. Interobserver ICCs for CTA and NC-MRI showed ranges of 0.62 to 0.99 (mean: 0.92) and 0.56 to 0.99 (mean: 0.91); intermodality ICCs for observer 1 and 2 showed ranges of 0.64 to 0.99 (mean: 0.92) and 0.56 to 0.99 (mean: 0.92). The CTA and NC-MRI vascular measurements correlated strongly, except for both external iliac artery diameters. The choice of stent size was always the same between the 2 observers; furthermore, graft size was always in agreement with that selected prospectively. CONCLUSION Computed tomography angiography remains the standard of reference for EVAR planning; NC-MRI can be an option for patients with contraindications for CTA, in particular those with renal impairment.
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Affiliation(s)
| | | | - Camilla Micieli
- 1 Radiology Department, University of Insubria, Varese, Italy
| | | | | | - Andrea Coppola
- 1 Radiology Department, University of Insubria, Varese, Italy
| | | | | | - Raffaele Novario
- 3 Department of Clinical and Biological Sciences, University of Insubria, Varese, Italy
| | - Carlo Fugazzola
- 1 Radiology Department, University of Insubria, Varese, Italy
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20
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Behr-Andersen C, Gammelgaard L, Fründ ET, Dahl M, Lindholt JS. Magnetic resonance imaging of the intraluminal thrombus in abdominal aortic aneurysms: a quantitative and qualitative evaluation and correlation with growth rate. THE JOURNAL OF CARDIOVASCULAR SURGERY 2017; 60:221-229. [PMID: 28847145 DOI: 10.23736/s0021-9509.17.09921-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The role of the intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA) growth remains incompletely understood. MRI is superior to other methods in depicting the morphology of the ILT. This study brings preliminary, but novel information on the presence and morphological characteristics of the ILT and AAA growth rates in a screening cohort. METHODS Cohort study with 46 patients from the Viborg Vascular Trial. All underwent one non-contrast-enhanced magnetic resonance imaging (MRI) at the end of follow-up. ILT presence was noted and, if present, it was allocated to one of four morphological categories based on visual appearance and signal intensity on T2 weighted images. RESULTS The mean growth rate was 1.95 mm/year ±0.87 (SD). The observation time was 5.59±0.63 (SD) years. ILT was present in AAA size groups as follows: 30-34.9 mm 20.00%, 35-39.9 mm 88.89%, 40-44.9 mm 81.25%, 45-49.9 mm 100% and 50-54.9 mm 100%. Out of 46, 8 had no ILT at the time of MRI. The presence of any sort of ILT yielded a significantly increased unadjusted and an adjusted growth rate of 1.09 mm/year (95% CI: 0.48; 1.70) and 1.24 mm/year (95% CI: 0.64; 1.83), respectively. All four thrombus types were retrospectively associated with an increased recorded growth rate compared with "no thrombus". Presence of a thin circumferential thrombus was retrospectively associated with the highest increase in growth rate, viz. 2.09 mm/year (95% CI: 1.23; 2.95). CONCLUSIONS We observed faster growth rate in those AAA that had developed an ILT. Even faster growth was observed amongst those AAA containing a thin ILT located along the inner circumference.
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Affiliation(s)
- Carsten Behr-Andersen
- Cardiovascular Research Center, Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark -
| | - Lise Gammelgaard
- Department of Radiology, Viborg Regional Hospital, Viborg, Denmark
| | - Ernst T Fründ
- Elitary Research Center of Individualized Treatment of Arterial Diseases (CIMA), Cardiovascular Center of Excellence (CAVAC), Department of Heart, Lung and Vascular Surgery, University Hospital of Odense, Denmark
| | - Marie Dahl
- Cardiovascular Research Center, Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark
| | - Jes S Lindholt
- Cardiovascular Research Center, Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark.,Elitary Research Center of Individualized Treatment of Arterial Diseases (CIMA), Cardiovascular Center of Excellence (CAVAC), Department of Heart, Lung and Vascular Surgery, University Hospital of Odense, Denmark
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21
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Di Achille P, Tellides G, Humphrey J. Hemodynamics-driven deposition of intraluminal thrombus in abdominal aortic aneurysms. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:10.1002/cnm.2828. [PMID: 27569676 PMCID: PMC5332472 DOI: 10.1002/cnm.2828] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 07/06/2016] [Accepted: 08/25/2016] [Indexed: 05/18/2023]
Abstract
Accumulating evidence suggests that intraluminal thrombus plays many roles in the natural history of abdominal aortic aneurysms. There is, therefore, a pressing need for computational models that can describe and predict the initiation and progression of thrombus in aneurysms. In this paper, we introduce a phenomenological metric for thrombus deposition potential and use hemodynamic simulations based on medical images from 6 patients to identify best-fit values of the 2 key model parameters. We then introduce a shape optimization method to predict the associated radial growth of the thrombus into the lumen based on the expectation that thrombus initiation will create a thrombogenic surface, which in turn will promote growth until increasing hemodynamically induced frictional forces prevent any further cell or protein deposition. Comparisons between predicted and actual intraluminal thrombus in the 6 patient-specific aneurysms suggest that this phenomenological description provides a good first estimate of thrombus deposition. We submit further that, because the biologically active region of the thrombus appears to be confined to a thin luminal layer, predictions of morphology alone may be sufficient to inform fluid-solid-growth models of aneurysmal growth and remodeling.
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Affiliation(s)
- P. Di Achille
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - G. Tellides
- Department of Surgery, Yale School of Medicine, New Haven, CT, USA
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
| | - J.D. Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
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22
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Kelsey LJ, Powell JT, Norman PE, Miller K, Doyle BJ. A comparison of hemodynamic metrics and intraluminal thrombus burden in a common iliac artery aneurysm. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:e2821. [PMID: 27509188 DOI: 10.1002/cnm.2821] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 06/06/2016] [Accepted: 07/02/2016] [Indexed: 06/06/2023]
Abstract
Aneurysms of the common iliac artery (CIAA) are typically found in association with an abdominal aortic aneurysm (AAA). Isolated CIAAs, in the absence of an AAA, are uncommon. Similar to AAAs, CIAA may develop intraluminal thrombus (ILT). As isolated CIAAs have a contralateral common iliac artery for comparison, they provide an opportunity to study the hemodynamic mechanisms behind ILT formation. In this study, we compared a large isolated CIAA and the contralateral iliac artery using computational fluid dynamics to determine if hemodynamic metrics correlate with the location of ILT. We performed a comprehensive computational fluid dynamics study and investigated the residence time of platelets and monocytes, velocity fields, time-averaged wall shear stress, oscillatory shear index, and endothelial cell activation potential. We then correlated these data to ILT burden determined with computed tomography. We found that high cell residence times, low time-averaged wall shear stress, high oscillatory shear index, and high endothelial cell activation potential all correlate with regions of ILT development. Our results show agreement with previous hypotheses of thrombus formation in AAA and provide insights into the computational hemodynamics of iliac artery aneurysms.
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Affiliation(s)
- Lachlan J Kelsey
- Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, Perth, WA, Australia
- Intelligent Systems for Medicine Laboratory, School of Mechanical and Chemical Engineering, The University of Western Australia, Crawley, WA, Australia
| | - Janet T Powell
- Vascular Surgery Research Group, Imperial College London, London, UK
| | - Paul E Norman
- Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, Perth, WA, Australia
- School of Surgery, The University of Western Australia, Crawley, WA, Australia
| | - Karol Miller
- Intelligent Systems for Medicine Laboratory, School of Mechanical and Chemical Engineering, The University of Western Australia, Crawley, WA, Australia
- Institute of Mechanics and Advanced Materials, Cardiff University, Cardiff, UK
| | - Barry J Doyle
- Vascular Engineering Laboratory, Harry Perkins Institute of Medical Research, Perth, WA, Australia
- School of Mechanical and Chemical Engineering, The University of Western Australia, Crawley, WA, Australia
- British Heart Foundation Centre for Cardiovascular Science, The University of Edinburgh, Edinburgh, UK
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23
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van Noort K, Schuurmann RC, Wermelink B, Slump CH, Kuijpers KC, de Vries JPP. Fluid displacement from intraluminal thrombus of abdominal aortic aneurysm as a result of uniform compression. Vascular 2017; 25:542-548. [PMID: 28441922 DOI: 10.1177/1708538117707612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Objectives The results after aneurysm repair with an endovascular aneurysm sealing (EVAS) system are dependent on the stability of the aneurysm sac and particularly the intraluminal abdominal aortic thrombus (ILT). The postprocedural ILT volume is decreased compared with preprocedural ILT volume in aortic aneurysm patients treated with EVAS. We hypothesize that ILT is not stable in all patients and pressurization of the ILT may result in displacement of fluids from the ILT, no differently than serum is displaced from whole blood when it settles. To date, the mechanism and quantification of fluid displacement from ILT are unknown. Methods The study included 21 patients who underwent elective open abdominal aortic aneurysm repair. The ILT was harvested as a routine procedure during the operation. After excision of a histologic sample of the ILT specimen in four patients, ILT volume was measured and the ILT was compressed in a dedicated compression setup designed to apply uniform compression of 200 mmHg for 5 min. After compression, the volumes of the remaining thrombus and the displaced fluid were measured. Results The median (interquartile-range) of ILT volume before compression was 60 (66) mL, and a median of 5.7 (8.4) mL of fluid was displaced from the ILT after compression, resulting in a median thrombus volume decrease of 11% (10%). Fluid components can be up to 31% of the entire ILT volume. Histologic examination of four ILT specimens showed a reduction of the medial layer of the ILT after compression, which was the result of compression of fluid-containing canaliculi. Conclusions Applying pressure of 200 mmHg to abdominal aortic aneurysm ILT resulted in the displacement of fluid, with a large variation among patients. Fluid displacement may result in decrease of ILT volume during and after EVAS, which might have implications on pre-EVAS volume planning and on stability of the endobags during follow-up which may lead to migration, endoleak or both.
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Affiliation(s)
- Kim van Noort
- 1 Department of Vascular Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands.,2 Technical Medicine, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Richte Cl Schuurmann
- 1 Department of Vascular Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands.,2 Technical Medicine, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Bryan Wermelink
- 1 Department of Vascular Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands.,2 Technical Medicine, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Cornelis H Slump
- 3 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Karel C Kuijpers
- 4 Department of Pathology, St. Antonius Hospital, Nieuwegein, The Netherlands
| | - Jean-Paul Pm de Vries
- 1 Department of Vascular Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
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24
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Abstract
Thromboembolic disorders are a major cause of morbidity and mortality worldwide. The progress in noninvasive imaging techniques has led to the development of radionuclide imaging based on SPECT and PET approaches to observe molecular and cellular processes that may underlie the onset and progression of disease. The advantages of using normal and genetically modified small animal research have spurred the development of dedicated small animal imaging systems. Animal models of venous and arterial thrombosis are largely used and have improved our understanding of the etiology and pathogenesis of thrombosis. Here, we review the literature regarding nuclear imaging of thrombosis in mice and rats.
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Affiliation(s)
- Marie-Cécile Valéra
- a Inserm, U1048 and Université Toulouse III , I2MC, Toulouse , France.,b Faculté de Chirurgie Dentaire, Université de Toulouse III , Toulouse , France
| | - Bernard Payrastre
- a Inserm, U1048 and Université Toulouse III , I2MC, Toulouse , France.,c Laboratoire d'Hématologie CHU de Toulouse , Toulouse , France
| | - Olivier Lairez
- a Inserm, U1048 and Université Toulouse III , I2MC, Toulouse , France.,d Fédération des services de cardiologie, Département de Médecine Nucléaire Centre d'imagerie cardiaque, CHU de Toulouse , Toulouse , France
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25
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Boersen J, Schuurmann R, Slump C, van den Heuvel D, Reijnen M, ter Mors T, Vahl A, de Vries J. Changes in Aortoiliac Anatomy After Elective Treatment of Infrarenal Abdominal Aortic Aneurysms with a Sac Anchoring Endoprosthesis. Eur J Vasc Endovasc Surg 2016; 51:56-62. [DOI: 10.1016/j.ejvs.2015.08.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 08/23/2015] [Indexed: 01/10/2023]
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26
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Georg Y, Delay C, Schwein A, Lejay A, Thaveau F, Gaertner S, Stephan D, Heim F, Chakfe N. [Contribution of mathematical models and biomechanical properties in predicting the risk of abdominal aortic aneurysm rupture]. ACTA ACUST UNITED AC 2015; 41:63-8. [PMID: 26318549 DOI: 10.1016/j.jmv.2015.07.107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 07/17/2015] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Rupture is the worst outcome of abdominal aortic aneurysm (AAA). The decision to operate should include counterbalancing the risk of aneurysm rupture against the risk of aneurysm repair, within the context of a patient's overall life expectancy. Current surgical guidelines are based on population studies, and important variables are missed in predicting individual risk of rupture. METHODS In this literature review, we focused on the contribution of biomechanical and mathematical models in predicting risk of AAA rupture. RESULTS Anatomical features as diameter asymmetry and lack of tortuosity are shown to be anatomical risk factors of rupture. Wall stiffness (due to modifications of elastin and collagen composition) and increased inflammatory response are also factors that affect the structural integrity of the AAA wall. Biomechanical studies showed that wall strength is lower in ruptured than non-ruptured AAA. Intra-luminal thrombus also has a big role to play in the occurrence of rupture. Current mathematical models allow more variables to be included in predicting individual risk of rupture. CONCLUSION Moving away from using maximal transverse diameter of the AAA as a unique predictive factor and instead including biological, structural and biomechanical variables in predicting individual risk of rupture will be essential in the future and will help gain precision and accuracy in surgical indications.
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Affiliation(s)
- Y Georg
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France
| | - C Delay
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France
| | - A Schwein
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France
| | - A Lejay
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France
| | - F Thaveau
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France
| | - S Gaertner
- Service des maladies vasculaires, hypertension artérielle et pharmacologie clinique, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67091 Strasbourg cedex, France
| | - D Stephan
- Service des maladies vasculaires, hypertension artérielle et pharmacologie clinique, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, 67091 Strasbourg cedex, France
| | - F Heim
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Laboratoire de physique et mécanique textile, ENSISA, 11, rue Alfred-Werner, 68093 Mulhouse cedex, France
| | - N Chakfe
- Groupe européen de recherche sur les prothèses appliquées à la chirurgie vasculaire (Geprovas), faculté de médecine, institut d'anatomie pathologique, 4, rue Kirschleger, 67085 Strasbourg cedex, France; Service de chirurgie vasculaire et transplantation rénale, hôpitaux universitaires de Strasbourg, 1, place de l'Hôpital, BP n(o) 426, 67091 Strasbourg cedex, France.
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Di Achille P, Tellides G, Figueroa CA, Humphrey JD. A haemodynamic predictor of intraluminal thrombus formation in abdominal aortic aneurysms. Proc Math Phys Eng Sci 2014. [DOI: 10.1098/rspa.2014.0163] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Intraluminal thrombus (ILT) is present in over 75% of all abdominal aortic aneurysms (AAAs) and probably contributes to the complex biomechanics and pathobiology of these lesions. A reliable predictor of thrombus formation in enlarging lesions could thereby aid clinicians in treatment planning. The primary goal of this work was to identify a new phenomenological metric having clinical utility that is motivated by the hypothesis that two basic haemodynamic features must coincide spatially and temporally to promote the formation of a thrombus on an intact endothelium—platelets must be activated within a shear flow and then be presented to a susceptible endothelium. Towards this end, we propose a new thrombus formation potential (TFP) that combines information on the flow-induced shear history experienced by blood-borne particles that come in close proximity to the endothelium with information on both the time-averaged wall shear stress (WSS) and the oscillatory shear index (OSI) that locally affect the endothelial mechanobiology. To illustrate the possible utility of this new metric, we show computational results for 10 carotid arteries from five patients where regions of low WSS and high OSI tend not to be presented with activated platelets (i.e. they have a low TFP), consistent with the thrombo-resistance of the healthy carotid despite its complex haemodynamics. Conversely, we show results for three patients that high TFP co-localizes with regions of observed thin thrombus in AAAs, which contrasts with findings of low TFP for the abdominal aorta of three healthy subjects. We submit that these promising results suggest the need for further consideration of the TFP, or a similar combined metric, as a potentially useful clinical predictor of the possible formation of ILT in AAAs.
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Affiliation(s)
- P. Di Achille
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - G. Tellides
- Department of Surgery, Yale School of Medicine, New Haven, CT, USA
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
| | - C. A. Figueroa
- Department of Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - J. D. Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
- Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
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MDCT distinguishing features of focal aortic projections (FAP) in acute clinical settings. Radiol Med 2014; 120:50-72. [PMID: 25249411 DOI: 10.1007/s11547-014-0459-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 08/14/2014] [Indexed: 01/25/2023]
Abstract
Focal aortic projections (FAP) are protrusion images of the contrast medium (focal contour irregularity, breaks in the intimal contour, outward lumen bulging or localized blood-filled outpouching) projecting beyond the aortic lumen in the aortic wall and are commonly seen on multidetector computed tomography (MDCT) scans of the chest and abdomen. FAP include several common and uncommon etiologies, which can be demonstrated both in the native aorta, mainly in acute aortic syndromes, and in the post-surgical aorta or after endovascular therapy. They are also found in some types of post-traumatic injuries and in impending rupture of the aneurysms. The expanding, routine use of millimetric or submillimetric collimation of current state-of-the-art MDCT scanners (16 rows and higher) all the time allows the identification and characterization of these small ulcer-like lesions or irregularities in the entire aorta, as either an incidental or expected finding, and provides detailed three-dimensional pictures of these pathologic findings. In this pictorial review, we illustrate the possible significance of FAP and the discriminating MDCT features that help to distinguish among different types of aortic protrusions and their possible evolution. Awareness of some related and distinctive radiologic features in FAP may improve our understanding of aortic diseases, provide further insight into the pathophysiology and natural history, and guide the appropriate management of these lesions.
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29
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Categorization of aortic aneurysm thrombus morphology by magnetic resonance imaging. Eur J Radiol 2013; 82:e544-9. [DOI: 10.1016/j.ejrad.2013.06.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 06/29/2013] [Indexed: 11/17/2022]
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30
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Wilson JS, Virag L, Di Achille P, Karsaj I, Humphrey JD. Biochemomechanics of intraluminal thrombus in abdominal aortic aneurysms. J Biomech Eng 2013; 135:021011. [PMID: 23445056 DOI: 10.1115/1.4023437] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Most computational models of abdominal aortic aneurysms address either the hemodynamics within the lesion or the mechanics of the wall. More recently, however, some models have appropriately begun to account for the evolving mechanics of the wall in response to the changing hemodynamic loads. Collectively, this large body of work has provided tremendous insight into this life-threatening condition and has provided important guidance for current research. Nevertheless, there has yet to be a comprehensive model that addresses the mechanobiology, biochemistry, and biomechanics of thrombus-laden abdominal aortic aneurysms. That is, there is a pressing need to include effects of the hemodynamics on both the development of the nearly ubiquitous intraluminal thrombus and the evolving mechanics of the wall, which depends in part on biochemical effects of the adjacent thrombus. Indeed, there is increasing evidence that intraluminal thrombus in abdominal aortic aneurysms is biologically active and should not be treated as homogeneous inert material. In this review paper, we bring together diverse findings from the literature to encourage next generation models that account for the biochemomechanics of growth and remodeling in patient-specific, thrombus-laden abdominal aortic aneurysms.
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Affiliation(s)
- J S Wilson
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
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31
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CT Angiography of Abdominal Aortic Aneurysms: Not Everything That Is Not White Is Thrombus. J Vasc Interv Radiol 2012; 23:1387-8. [DOI: 10.1016/j.jvir.2012.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/01/2012] [Accepted: 07/02/2012] [Indexed: 11/19/2022] Open
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32
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Affiliation(s)
- Denis B Buxton
- Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, 6701 Rockledge Drive, Bethesda, MD 20817, USA.
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33
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Celi S, Losi P, Berti S. Investigation on regional variation of intraluminal thrombus: A mechanical and histological study. BIOINSPIRED BIOMIMETIC AND NANOBIOMATERIALS 2012. [DOI: 10.1680/bbn.12.00006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The abdominal aortic aneurysm is an irreversible dilatation of the artery and when this pathology is localized in the aortic district, the intraluminal thrombus (ILT) is present in approximately 75% of cases. The rupture risk of AAA is thought to be associated with increased levels of wall stress. In recent decades, finite element analysis (FEA) have been used to predict wall stresses in a patient-specific, noninvasive manner. However, FE simulations are mainly based on homogeneous behavior for ILT material. The purpose of this work was to investigate the biomechanical behavior of ILT and to derive an appropriate constitutive relation for ventral and posterior regions. Uniaxial tensile tests were carried out and histological investigations were performed on four fresh thrombi to correlate with the change in the mechanical properties. A second-order polynomial, large-strain, hyperelastic constitutive model was developed and used to fit the uniaxial tensile testing data for determination of the material parameters. Our results indicate that the microstructure of ILT differs between the ventral and dorsal region, with the area region characterized by a nonlinear behavior and the lateral posterior area stiffer than the budge region. The peak stretch values were (mean±SEM) 1·24±0·04 and 1·1±0·09 for the ventral and lateral posterior area of the ILT, respectively. The material models for the thrombi are in excellent agreement with the experimental data.
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Affiliation(s)
- Simona Celi
- Postdoctoral Researcher at Institute of Clinical Physiology of National Council of Research. Laboratory of Biomechanics at Gabriele Monasterio Tuscany Foundation, Heart Hospital, Massa, Italy
| | - Paola Losi
- Researcher at Institute of Clinical Physiology of National Council of Research. Laboratory for Biomaterials and Graft Technology, Massa, Italy
| | - Sergio Berti
- Main Director of the Adult Cardiology Unit at Gabriele Monasterio Tuscany Foundation, Heart Hospital, Massa, Italy
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