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Elefteriades JA, Ziganshin BA, Zafar MA. Nonsize Criteria for Surgical Intervention on the Ascending Thoracic Aorta. AORTA (STAMFORD, CONN.) 2023; 11:71-86. [PMID: 37172942 PMCID: PMC10232037 DOI: 10.1055/s-0043-1766114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/02/2023] [Indexed: 05/15/2023]
Abstract
For decades, aortic surgery has relied on size criteria for intervention on the ascending aorta. While diameter has served well, diameter alone falls short of an ideal criterion. Herein, we examine the potential application of other, nondiameter criteria in aortic decision-making. These findings are summarized in this review. We have conducted multiple investigations of specific alternate nonsize criteria by leveraging our extensive database, which includes complete, verified anatomic, clinical, and mortality data on 2,501 patients with thoracic aortic aneurysm (TAA) and dissections (198 Type A, 201 Type B, and 2102 TAAs). We examined 14 potential intervention criteria. Each substudy had its own specific methodology, reported individually in the literature. The overall findings of these studies are presented here, with a special emphasis on how the findings can be incorporated into enhanced aortic decision-making-above and beyond sheer diameter. The following nondiameter criteria have been found useful in decision-making regarding surgical intervention. (1) Pain: In the absence of other specific cause, substernal chest pain mandates surgery. Well-developed afferent neural pathways carry warning signals to the brain. (2) Aortic length/tortuosity: Length is emerging as a mildly better predictor of impending events than diameter. (3) Genes: Specific genetic aberrations provide a powerful predictor of aortic behavior; malignant genetic variants obligate earlier surgery. (4) Family history: Aortic events closely follow those in relatives with a threefold increase in likelihood of aortic dissection for other family members once an index family dissection has occurred. (5) Bicuspid aortic valve: Previously thought to increase aortic risk (as a "Marfan light" situation), current data show that bicuspid valve is not a predictor of higher risk. (6) Diabetes actually protects against aortic events, via mural thickening and fibrosis. (7) Biomarkers: A specialized "RNA signature test" identifies aneurysm-bearing patients in the general population and promises to predict impending dissection. (8) Aortic stress: Blood pressure (BP) elevation from anxiety/exertion precipitates dissection, especially with high-intensity weightlifting. (9) Root dilatation imposes higher dissection risk than supracoronary ascending aneurysm. (10) Inflammation on positron emission tomography (PET) imaging implies high rupture risk and merits surgical intervention. (11) A KIF6 p.Trp719Arg variant elevates aortic dissection risk nearly two-fold. (12) Female sex confers some increased risk, which can be largely accommodated by using body-size-based nomograms (especially height nomograms). (13) Fluoroquinolones predispose to catastrophic dissection events and should be avoided rigorously in aneurysm patients. (14) Advancing age makes the aorta more vulnerable, increasing likelihood of dissection. In conclusion, nondiameter criteria can beneficially be brought to bear on the decision to observe or operate on specific TAA.
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Affiliation(s)
- John A. Elefteriades
- Aortic Institute at Yale-New Haven, Yale University School of Medicine, New Haven, Connecticut
| | - Bulat A. Ziganshin
- Aortic Institute at Yale-New Haven, Yale University School of Medicine, New Haven, Connecticut
| | - Mohammad A. Zafar
- Aortic Institute at Yale-New Haven, Yale University School of Medicine, New Haven, Connecticut
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2
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Culture-Negative Mycotic Aortic Aneurysms Probably Have a Less Severe Clinical Nature Than Culture-Positive Counterparts. Ann Vasc Surg 2021; 75:150-161. [PMID: 33831517 DOI: 10.1016/j.avsg.2021.03.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/14/2021] [Accepted: 03/01/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Mycotic aortic aneurysm constitutes a potentially devastating disease that necessitates prompt suspicion and diagnosis. There is no exact consensus for treatment, but removal of infected tissues and prolonged use of antimicrobials based on the identified causative microorganisms seem widely acceptable and have been similarly practiced worldwide. However, some patients still show no identified microorganisms. In this study, we sought to determine whether there are any clinical significance or differences of note in culture-negative mycotic aortic aneurysms. METHODS Between October 2003 and August 2018, 71 patients were identified as treated for mycotic aortic aneurysms at a single tertiary institution. Review of medical records and imaging studies were completed to collect the following information: demographics, previous medical/surgical history regarding potential infection sources, laboratory and radiologic findings, clinical presentations, treatment method, and morbidity and mortality rates. For analysis, patients were categorized into two groups: the blood and/or tissue culture-positive (CP) group and the blood and/or tissue culture-negative (CN) group. The latter was further divided as CN with identified microorganism by molecular biologic methods [CN(+)] and CN with no identified microorganism [CN(-)]. RESULTS More patients in the CP group were symptomatic than were in the CN(+) group (100% vs. 80%; P = 0.034). However, identification of causative microorganisms did not result in a difference in symptom status upon comparing the [CP + CN(+)] and [CN(-)] groups. Inflammatory markers were the most elevated in the CP group and least elevated in the CN(-) group. The aneurysm growth rate seemed slower in the CN(-) group than in the CN(+) and CP groups (1.3 vs. 3.4 vs. 9 mm/month respectively). Aneurysm rupture at initial presentation was more prevalent in the CP group (33.3%). 18F-Fluorodeoxyglucose-positron emission tomography showed increased uptake regardless of whether or not the microorganisms were identified. Early mortality and disease-specific mortality rates during the follow-up period were higher in the CP group but without statistical significance. CONCLUSIONS Compared with the CP group, the CN groups appeared clinically less severe, and also exhibited a relatively less devastating course as exhibited by the slower aneurysm expansion rate and smaller number of ruptured aneurysms at the initial presentation.
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Multimodality Imaging of Aortic Disease. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2020. [DOI: 10.1007/s11936-020-00831-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Sladojevic M, Zlatanovic P, Stanojevic Z, Koncar I, Vidicevic S, Tasic J, Isakovic A, Tomic I, Mutavdzic P, Stevanovic K, Trailovic R, Davidovic L. Influence of preoperative statins and aspirin administration on biological and magnetic resonance imaging properties in patients with abdominal aortic aneurysm. VASA 2020; 50:116-124. [PMID: 32669062 DOI: 10.1024/0301-1526/a000895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Background: Main objective of this study was to evaluate the influence of statins and/or acetylsalicylic acid on biochemical characteristics of abdominal aortic aneurysm (AAA) wall and intraluminal thrombus (ILT). Patients and methods: Fifty patients with asymptomatic infrarenal AAA were analyzed using magnetic resonance imaging on T1w sequence. Relative ILT signal intensity (SI) was determined as a ratio between ILT and psoas muscle SI. Samples containing the full ILT thickness and aneurysm wall were harvested from the anterior surface at the level of the maximal diameter. The concentration of enzymes such as matrix metalloproteinase (MMP) 9, MMP2 and neutrophil elastase (NE/ELA) were analyzed in ILT and AAA wall; while collagen type III, elastin and proteoglycan 4 were analyzed in harvested AAA wall. Oxidative stress in the AAA wall was assessed by catalase and malondialdehyde activity in tissue samples. Results: Relative ILT signal intensity (1.09 ± 0.41 vs 0.89 ± 0.21, p = 0.013) were higher in non-statin than in statin group. Patients who were taking aspirin had lower relative ILT area (0.89 ± 0.19 vs 1.13. ± 0.44, p = 0.016), and lower relative ILT signal intensity (0.85 [0.73-1.07] vs 1.01 [0.84-1.19], p = 0.021) compared to non-aspirin group. There were higher concentrations of elastin in AAA wall among patients taking both of aspirin and statins (1.21 [0.77-3.02] vs 0.78 (0.49-1.05) ng/ml, p = 0.044) than in patients who did not take both of these drugs. Conclusions: Relative ILT SI was lower in patients taking statin and aspirin. Combination of antiplatelet therapy and statins was associated with higher elastin concentrations in AAA wall.
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Affiliation(s)
- Milos Sladojevic
- School of Medicine, University of Belgrade, Serbia.,Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Petar Zlatanovic
- Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Zeljka Stanojevic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Serbia
| | - Igor Koncar
- School of Medicine, University of Belgrade, Serbia.,Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Sasenka Vidicevic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Serbia
| | - Jelena Tasic
- Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Serbia
| | - Aleksandra Isakovic
- Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia.,Institute of Medical and Clinical Biochemistry, School of Medicine, University of Belgrade, Serbia
| | - Ivan Tomic
- School of Medicine, University of Belgrade, Serbia.,Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Perica Mutavdzic
- Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Ksenija Stevanovic
- School of Medicine, University of Belgrade, Serbia.,Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Ranko Trailovic
- Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
| | - Lazar Davidovic
- School of Medicine, University of Belgrade, Serbia.,Clinic for Vascular and Endovascular Surgery, Clinical Center of Serbia, Belgrade, Serbia
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Joshi NV, Elkhawad M, Forsythe RO, McBride OMB, Rajani NK, Tarkin JM, Chowdhury MM, Donoghue E, Robson JMJ, Boyle JR, Fryer TD, Huang Y, Teng Z, Dweck MR, Tawakol AA, Gillard JH, Coughlin PA, Wilkinson IB, Newby DE, Rudd JHF. Greater aortic inflammation and calcification in abdominal aortic aneurysmal disease than atherosclerosis: a prospective matched cohort study. Open Heart 2020; 7:e001141. [PMID: 32201583 PMCID: PMC7066636 DOI: 10.1136/openhrt-2019-001141] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 01/06/2020] [Accepted: 01/21/2020] [Indexed: 01/24/2023] Open
Abstract
Objective Using combined positron emission tomography and CT (PET-CT), we measured aortic inflammation and calcification in patients with abdominal aortic aneurysms (AAA), and compared them with matched controls with atherosclerosis. Methods We prospectively recruited 63 patients (mean age 76.1±6.8 years) with asymptomatic aneurysm disease (mean size 4.33±0.73 cm) and 19 age-and-sex-matched patients with confirmed atherosclerosis but no aneurysm. Inflammation and calcification were assessed using combined 18F-FDG PET-CT and quantified using tissue-to-background ratios (TBRs) and Agatston scores. Results In patients with AAA, 18F-FDG uptake was higher within the aneurysm than in other regions of the aorta (mean TBRmax2.23±0.46 vs 2.12±0.46, p=0.02). Compared with atherosclerotic control subjects, both aneurysmal and non-aneurysmal aortae showed higher 18F-FDG accumulation (total aorta mean TBRmax2.16±0.51 vs 1.70±0.22, p=0.001; AAA mean TBRmax2.23±0.45 vs 1.68±0.21, p<0.0001). Aneurysms containing intraluminal thrombus demonstrated lower 18F-FDG uptake within their walls than those without (mean TBRmax2.14±0.43 vs 2.43±0.45, p=0.018), with thrombus itself showing low tracer uptake (mean TBRmax thrombus 1.30±0.48 vs aneurysm wall 2.23±0.46, p<0.0001). Calcification in the aneurysmal segment was higher than both non-aneurysmal segments in patients with aneurysm (Agatston 4918 (2901-8008) vs 1017 (139-2226), p<0.0001) and equivalent regions in control patients (442 (304-920) vs 166 (80-374) Agatston units per cm, p=0.0042). Conclusions The entire aorta is more inflamed in patients with aneurysm than in those with atherosclerosis, perhaps suggesting a generalised inflammatory aortopathy in patients with aneurysm. Calcification was prominent within the aneurysmal sac, with the remainder of the aorta being relatively spared. The presence of intraluminal thrombus, itself metabolically relatively inert, was associated with lower levels of inflammation in the adjacent aneurysmal wall.
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Affiliation(s)
- Nikhil V Joshi
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Maysoon Elkhawad
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Rachael O Forsythe
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Olivia M B McBride
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Nikil K Rajani
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Jason M Tarkin
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Mohammed M Chowdhury
- Department of Vascular Surgery, University of Cambridge, Cambridge, United Kingdom
| | - Emma Donoghue
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | - Jonathan R Boyle
- Department of Vascular Surgery, University of Cambridge, Cambridge, United Kingdom
| | - Tim D Fryer
- Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom
| | - Yuan Huang
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Zhongzhao Teng
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
| | - Marc R Dweck
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | - Jonathan H Gillard
- Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, United Kingdom
| | - Patrick A Coughlin
- Department of Vascular Surgery, University of Cambridge, Cambridge, United Kingdom
| | - Ian B Wilkinson
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom
| | - David E Newby
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - James H F Rudd
- Division of Cardiovascular Medicine, University of Cambridge, Cambridge, UK
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6
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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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7
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Kelly MJ, Igari K, Yamanouchi D. Osteoclast-Like Cells in Aneurysmal Disease Exhibit an Enhanced Proteolytic Phenotype. Int J Mol Sci 2019; 20:ijms20194689. [PMID: 31546645 PMCID: PMC6801460 DOI: 10.3390/ijms20194689] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 12/29/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is among the top 20 causes of death in the United States. Surgical repair is the gold standard for AAA treatment, therefore, there is a need for non-invasive therapeutic interventions. Aneurysms are more closely associated with the osteoclast-like catabolic degradation of the artery, rather than the osteoblast-like anabolic processes of arterial calcification. We have reported the presence of osteoclast-like cells (OLCs) in human and mouse aneurysmal tissues. The aim of this study was to examine OLCs from aneurysmal tissues as a source of degenerative proteases. Aneurysmal and control tissues from humans, and from the mouse CaPO4 and angiotensin II (AngII) disease models, were analyzed via flow cytometry and immunofluorescence for the expression of osteoclast markers. We found higher expression of the osteoclast markers tartrate-resistant acid phosphatase (TRAP), matrix metalloproteinase-9 (MMP-9), and cathepsin K, and the signaling molecule, hypoxia-inducible factor-1α (HIF-1α), in aneurysmal tissue compared to controls. Aneurysmal tissues also contained more OLCs than controls. Additionally, more OLCs from aneurysms express HIF-1α, and produce more MMP-9 and cathepsin K, than myeloid cells from the same tissue. These data indicate that OLCs are a significant source of proteases known to be involved in aortic degradation, in which the HIF-1α signaling pathway may play an important role. Our findings suggest that OLCs may be an attractive target for non-surgical suppression of aneurysm formation due to their expression of degradative proteases.
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Affiliation(s)
- Matthew J Kelly
- Division of Vascular Surgery, Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
| | - Kimihiro Igari
- Division of Vascular Surgery, Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
- Division of Vascular and Endovascular Surgery, Department of Surgery, Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan.
| | - Dai Yamanouchi
- Division of Vascular Surgery, Department of Surgery, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
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8
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Kim J, Song HC. Role of PET/CT in the Evaluation of Aortic Disease. Chonnam Med J 2018; 54:143-152. [PMID: 30288369 PMCID: PMC6165921 DOI: 10.4068/cmj.2018.54.3.143] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/26/2018] [Accepted: 07/30/2018] [Indexed: 01/18/2023] Open
Abstract
Positron emission tomography (PET) /computed tomography (CT) has been established as a standard imaging modality in the evaluation of malignancy. Although PET/CT has played a major role in the management of oncology patients, its clinical use has also increased for various disorders other than malignancy. Growing evidence shows that PET/CT images have many advantages in aortic disease as well. This review article addresses the potential role of PET/CT in diseases involving the aorta, emphasizing its usefulness with regard to acute thoracic aortic syndromes, aortic aneurysm, atherosclerotic lesions, aortitis and aortic tumors.
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Affiliation(s)
- Jahae Kim
- Department of Nuclear Medicine, Chonnam National University Hospital, Gwangju, Korea
| | - Ho-Chun Song
- Department of Nuclear Medicine, Chonnam National University Hospital, Gwangju, Korea.,Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Korea
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9
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Abstract
PET/computed tomography (CT) can evaluate the metabolic and anatomic involvement of a variety of inflammatory, infectious, and malignant cardiovascular disorders. PET/CT is useful in evaluating coronary vasculature, hibernating myocardium, cardiac sarcoidosis, cardiac amyloidosis, cerebrovascular disease, acute aortic syndromes, cardiac and vascular neoplasms, cardiac and vascular infections, and vasculitis. Novel targeted radiopharmaceutical agents and novel use of established techniques show promise in diagnosing and monitoring cardiovascular diseases.
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Affiliation(s)
- Elizabeth H Dibble
- Department of Diagnostic Imaging, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903, USA.
| | - Don C Yoo
- Department of Diagnostic Imaging, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, 593 Eddy Street, Providence, RI 02903, USA
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Brangsch J, Reimann C, Collettini F, Buchert R, Botnar RM, Makowski MR. Molecular Imaging of Abdominal Aortic Aneurysms. Trends Mol Med 2017; 23:150-164. [PMID: 28110838 DOI: 10.1016/j.molmed.2016.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/06/2016] [Accepted: 12/11/2016] [Indexed: 12/21/2022]
Abstract
Abdominal aortic aneurysms (AAAs) represent a vascular disease with severe complications. AAAs are currently the overall 10th leading cause of death in western countries and their incidence is rising. Although different diagnostic techniques are currently available in clinical practice, including ultrasound (US), magnetic resonance imaging (MRI), and computed tomography (CT), imaging-based prediction of life-threatening complications such as aneurysm-rupture remains challenging. Molecular imaging provides a novel diagnostic approach for in vivo visualization of biological processes and pathological alterations at a cellular and molecular level. Its overall aim is to improve our understanding of disease pathogenesis and to facilitate novel diagnostic pathways. This review outlines recent preclinical and clinical developments in molecular MRI, positron emission tomography (PET), and single-photon emission computed tomography (SPECT) for imaging of AAAs.
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Affiliation(s)
- Julia Brangsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Carolin Reimann
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Federico Collettini
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Ralf Buchert
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - René M Botnar
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany; Division of Imaging Sciences and Biomedical Engineering, King's College London, London WC2R 2LS, UK; Wellcome Trust and Engineering and Physical Sciences Research Council (EPSRC) Medical Engineering Centre, King's College London, London SE1 7EH, UK; British Heart Foundation (BHF) Centre of Excellence, King's College London, London SE5 9NU, UK; National Institute for Health Research (NIHR) Biomedical Research Centre, King's College London, London SE1 9RT, UK
| | - Marcus R Makowski
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany; Division of Imaging Sciences and Biomedical Engineering, King's College London, London WC2R 2LS, UK.
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11
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Positron Emission Tomography and Magnetic Resonance Imaging of Cellular Inflammation in Patients with Abdominal Aortic Aneurysms. Eur J Vasc Endovasc Surg 2016; 51:518-26. [PMID: 26919936 PMCID: PMC4829709 DOI: 10.1016/j.ejvs.2015.12.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 12/12/2015] [Indexed: 11/23/2022]
Abstract
Objectives Inflammation is critical in the pathogenesis of abdominal aortic aneurysm (AAA) disease. Combined 18F-fludeoxyglucose (18F-FDG) positron emission tomography with computed tomography (PET-CT) and ultrasmall superparamagnetic particles of iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) are non-invasive methods of assessing tissue inflammation. The aim of this study was to compare these techniques in patients with AAA. Materials and methods Fifteen patients with asymptomatic AAA with diameter 46 ± 7 mm underwent PET-CT with 18F-FDG, and T2*-weighted MRI before and 24 hours after administration of USPIO. The PET-CT and MRI data were then co-registered. Standardised uptake values (SUVs) were calculated to measure 18F-FDG activity, and USPIO uptake was determined using the change in R2*. Comparisons between the techniques were made using a quadrant analysis and a voxel-by-voxel evaluation. Results When all areas of the aneurysm were evaluated, there was a modest correlation between the SUV on PET-CT and the change in R2* on USPIO-enhanced MRI (n = 70,345 voxels; r = .30; p < .0001). Although regions of increased 18F-FDG and USPIO uptake co-localised on occasion, this was infrequent (kappa statistic 0.074; 95% CI 0.026–0.122). 18F-FDG activity was commonly focused in the shoulder region whereas USPIO uptake was more apparent in the main body of the aneurysm. Maximum SUV was lower in patients with mural USPIO uptake. Conclusions Both 18F-FDG PET-CT and USPIO-MRI uptake identify vascular inflammation associated with AAA. Although they demonstrate a modest correlation, there are distinct differences in the pattern and distribution of uptake, suggesting a differential detection of macrophage glycolytic and phagocytic activity respectively.
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12
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Baratto L, Marrapodi G, Crivellaro C, Guerra L, Landoni C. Contained rupture of common iliac artery aneurysm in a contrast-enhanced PET/CT study. Rev Esp Med Nucl Imagen Mol 2016. [DOI: 10.1016/j.remnie.2015.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Baratto L, Marrapodi G, Crivellaro C, Guerra L, Landoni C. Contained rupture of common iliac artery aneurysm in a contrast-enhanced PET/CT study. Rev Esp Med Nucl Imagen Mol 2016; 35:56-7. [DOI: 10.1016/j.remn.2015.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/22/2015] [Accepted: 03/23/2015] [Indexed: 11/16/2022]
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14
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Shi S, Orbay H, Yang Y, Graves SA, Nayak TR, Hong H, Hernandez R, Luo H, Goel S, Theuer CP, Nickles RJ, Cai W. PET Imaging of Abdominal Aortic Aneurysm with 64Cu-Labeled Anti-CD105 Antibody Fab Fragment. J Nucl Med 2015; 56:927-32. [PMID: 25883125 DOI: 10.2967/jnumed.114.153098] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/31/2015] [Indexed: 01/11/2023] Open
Abstract
UNLABELLED The critical challenge in abdominal aortic aneurysm (AAA) research is the accurate diagnosis and assessment of AAA progression. Angiogenesis is a pathologic hallmark of AAA, and CD105 is highly expressed on newly formed vessels. Our goal was to use (64)Cu-labeled anti-CD105 antibody Fab fragment for noninvasive assessment of angiogenesis in the aortic wall in a murine model of AAA. METHODS Fab fragment of TRC105, a mAb that specifically binds to CD105, was generated by enzymatic papain digestion and conjugated to NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) for (64)Cu labeling. The binding affinity/specificity of NOTA-TRC105-Fab was evaluated by flow cytometry and various ex vivo studies. BALB/c mice were anesthetized and treated with calcium phosphate to induce AAA and underwent weekly PET scans using (64)Cu-NOTA-TRC105-Fab. Biodistribution and autoradiography studies were also performed to confirm the accuracy of PET results. RESULTS NOTA-TRC105-Fab exhibited high purity and specifically bound to CD105 in vitro. Uptake of (64)Cu-NOTA-TRC105-Fab increased from a control level of 3.4 ± 0.1 to 9.5 ± 0.4 percentage injected dose per gram (%ID/g) at 6 h after injection on day 5 and decreased to 7.2 ± 1.4 %ID/g on day 12, which correlated well with biodistribution and autoradiography studies (i.e., much higher tracer uptake in AAA than normal aorta). Of note, enhanced AAA contrast was achieved, due to the minimal background in the abdominal area of mice. Degradation of elastic fibers and highly expressed CD105 were observed in ex vivo studies. CONCLUSION (64)Cu-NOTA-TRC105-Fab cleared rapidly through the kidneys, which enabled noninvasive PET imaging of the aorta with enhanced contrast and showed increased angiogenesis (CD105 expression) during AAA. (64)Cu-NOTA-TRC105-Fab PET may potentially be used for future diagnosis and prognosis of AAA.
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Affiliation(s)
- Sixiang Shi
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hakan Orbay
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Yunan Yang
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Stephen A Graves
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Tapas R Nayak
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hao Hong
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Reinier Hernandez
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Haiming Luo
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Shreya Goel
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - Robert J Nickles
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Weibo Cai
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
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15
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Courtois A, Nusgens BV, Hustinx R, Namur G, Gomez P, Kuivaniemi H, Defraigne JO, Colige AC, Sakalihasan N. Gene expression study in positron emission tomography-positive abdominal aortic aneurysms identifies CCL18 as a potential biomarker for rupture risk. Mol Med 2015; 20:697-706. [PMID: 25517227 DOI: 10.2119/molmed.2014.00065] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 12/09/2014] [Indexed: 11/06/2022] Open
Abstract
Rupture of abdominal aortic aneurysm (AAA) is a cause of significant mortality and morbidity in aging populations. Uptake of 18-fluorodeoxyglucose (FDG) detected by positron emission tomography (PET) is observed in the wall of 12% of AAA (A+), with most of them being symptomatic. We previously showed that the metabolically active areas displayed adventitial inflammation, medial degeneration and molecular alterations prefacing wall rupture. The aim of this study was to identify new factors predictive of rupture. Transcriptomic analyses were performed in the media and adventitia layers from three types of samples: AAA with-out FDG uptake (A0) and with FDG uptake (A+), both at the positive spot (A+(Pos)) and at a paired distant negative site (A+(Neg)) of the same aneurysm. Follow-up studies included reverse-transcriptase-polymerase chain reaction (RT-PCR), immunohistochemical staining and enzyme-linked immunosorbent assay (ELISA). A large number of genes, including matrix metalloproteinases, collagens and cytokines as well as genes involved in osteochondral development, were differentially expressed in the A+(Pos) compared with A+(Neg). Moreover, a series of genes (notably CCL18) was differentially expressed both in the A+(Neg) and A+(Pos) compared with the A0. A significant increase of CCL18 was also found at the protein level in the aortic wall and in peripheral blood of A+ patients compared with A0. In conclusion, new factors, including CCL18, involved in the progression of AAA and, potentially, in their rupture were identified by a genome-wide analysis of PET-positive and -negative human aortic tissue samples. Further work is needed to study their role in AAA destabilization and weakening.
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Affiliation(s)
- Audrey Courtois
- Surgical Research Center, GIGA-Cardiovascular Science Unit, University of Liège, Liège, Belgium.,Laboratory of Connective Tissues Biology, GIGA-Research (GIGA-R), University of Liège, Liège, Belgium.,Department of Cardiovascular and Thoracic Surgery, University Hospital of Liège (CHU), University of Liège, Liège, Belgium
| | - Betty V Nusgens
- Laboratory of Connective Tissues Biology, GIGA-Research (GIGA-R), University of Liège, Liège, Belgium
| | - Roland Hustinx
- Department of Nuclear Medicine, University Hospital of Liège (CHU), University of Liège, Liège, Belgium
| | - Gauthier Namur
- Department of Nuclear Medicine, University Hospital of Liège (CHU), University of Liège, Liège, Belgium.,Department of Nuclear Medicine, St Joseph Hospital (CHC), Liège, Belgium
| | - Pierre Gomez
- Department of Nuclear Medicine, St Joseph Hospital (CHC), Liège, Belgium
| | - Helena Kuivaniemi
- The Sigfried and Janet Weis Center for Research, Geisinger Health System, Danville, Pennsylvania, United States of America.,Department of Surgery, Temple University School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Jean-Olivier Defraigne
- Department of Cardiovascular and Thoracic Surgery, University Hospital of Liège (CHU), University of Liège, Liège, Belgium
| | - Alain C Colige
- Laboratory of Connective Tissues Biology, GIGA-Research (GIGA-R), University of Liège, Liège, Belgium
| | - Natzi Sakalihasan
- Surgical Research Center, GIGA-Cardiovascular Science Unit, University of Liège, Liège, Belgium.,Department of Nuclear Medicine, University Hospital of Liège (CHU), University of Liège, Liège, Belgium
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16
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Increased 18F-FDG uptake is predictive of rupture in a novel rat abdominal aortic aneurysm rupture model. Ann Surg 2015; 261:395-404. [PMID: 24651130 DOI: 10.1097/sla.0000000000000602] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE To determine whether F-fluorodeoxyglucose (F-FDG) micro-positron emission tomography (micro-PET) can predict abdominal aortic aneurysm (AAA) rupture. BACKGROUND An infrarenal AAA model is needed to study inflammatory mechanisms that drive rupture. F-FDG PET can detect vascular inflammation in animal models and patients. METHODS After exposing Sprague-Dawley rats to intra-aortic porcine pancreatic elastase (PPE) (12 U/mL), AAA rupture was induced by daily, subcutaneous, β-aminopropionitrile (BAPN, 300 mg/kg, N = 24) administration. Negative control AAA animals (N = 15) underwent daily saline subcutaneous injection after PPE exposure. BAPN-exposed animals that did not rupture served as positive controls [nonruptured AAA (NRAAA) 14d, N = 9]. Rupture was witnessed using radiotelemetry. Maximum standard uptakes for F-FDG micro-PET studies were determined. Aortic wall PAI-1, uPA, and tPA concentrations were determined by western blot analyses. Interleukin (IL)-1β, IL-6, IL-10, and MIP-2 were determined by Bio-Plex bead array. Neutrophil and macrophage populations per high-power field were quantified. Matrix metalloproteinase (MMP) activities were determined by zymography. RESULTS When comparing ruptured AAA (RAAA) to NRAAA 14d animals, increased focal F-FDG uptakes were detected at subsequent sites of rupture (P = 0.03). PAI-1 expression was significantly less in RAAA tissue (P = 0.01), with comparable uPA and decreased tPA levels (P = 0.02). IL-1β (P = 0.04), IL-6 (P = 0.001), IL-10 (P = 0.04), and MIP-2 (P = 0.02) expression, neutrophil (P = 0.02) and macrophage presence (P = 0.002), and MMP9 (P < 0.0001) activity were increased in RAAA tissue. CONCLUSIONS With this AAA rupture model, increased prerupture F-FDG uptake on micro-PET imaging was associated with increased inflammation in the ruptured AAA wall. F-FDG PET imaging may be used to monitor inflammatory changes before AAA rupture.
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17
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Vascular inflammation in a growing iliac artery aneurysm. Clin Nucl Med 2015; 40:e323-4. [PMID: 25674872 DOI: 10.1097/rlu.0000000000000731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have used a multimodality imaging approach to assess the inflammatory component of a growing iliac artery aneurysm in a 53-year-old man who presented with related ureteral obstruction. Research suggests that episodic and heterogeneous inflammatory processes are important for the progression of aneurysms. The combined PET and MRI evaluation of inflammation that we present here is a novel approach to vascular imaging that is well suited for emerging hybrid PET/MRI systems.
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18
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Golestani R, Razavian M, Nie L, Zhang J, Jung JJ, Ye Y, de Roo M, Hilgerink K, Liu C, Robinson SP, Sadeghi MM. Imaging vessel wall biology to predict outcome in abdominal aortic aneurysm. Circ Cardiovasc Imaging 2015; 8:e002471. [PMID: 25550400 PMCID: PMC4284949 DOI: 10.1161/circimaging.114.002471] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Abdominal aortic aneurysm (AAA) rupture risk is currently determined based on size and symptoms. This approach does not address the rupture risk associated with small aneurysms. Given the role of matrix metalloproteinases (MMPs) in AAA weakening and rupture, we investigated the potential of MMP-targeted imaging for detection of aneurysm biology and prediction of outcome in a mouse model of AAA with spontaneous rupture. METHODS AND RESULTS Fifteen-week-old mice (n=66) were infused with angiotensin II for 4 weeks to induce AAA. Saline-infused mice (n=16) served as control. The surviving animals underwent in vivo MMP-targeted micro-single photon emission computed tomographic/computed tomographic imaging, using RP805, a technetium-99m-labeled MMP-specific tracer, followed by ex vivo planar imaging, morphometry, and gene expression analysis. RP805 uptake in suprarenal aorta on micro-single photon emission computed tomographic images was significantly higher in animals with AAA when compared with angiotensin II-infused animals without AAA or control animals. CD68 expression and MMP activity were increased in AAA, and significant correlations were noted between RP805 uptake and CD68 expression or MMP activity but not aortic diameter. A group of angiotensin II-infused animals (n=24) were imaged at 1 week and were followed up for additional 3 weeks. RP805 uptake in suprarenal aorta at 1 week was significantly higher in mice that later developed rupture or AAA. Furthermore, tracer uptake at 1 week correlated with aortic diameter at 4 weeks. CONCLUSIONS MMP-targeted imaging reflects vessel wall inflammation and can predict future aortic expansion or rupture in murine AAA. If confirmed in humans, this may provide a new paradigm for AAA risk stratification.
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MESH Headings
- Angiotensin II
- Animals
- Antigens, CD/metabolism
- Antigens, Differentiation, Myelomonocytic/metabolism
- Aorta, Abdominal/diagnostic imaging
- Aorta, Abdominal/metabolism
- Aorta, Abdominal/pathology
- Aortic Aneurysm, Abdominal/chemically induced
- Aortic Aneurysm, Abdominal/diagnosis
- Aortic Aneurysm, Abdominal/metabolism
- Aortic Rupture/diagnosis
- Aortic Rupture/etiology
- Aortic Rupture/metabolism
- Aortography
- Biomarkers/metabolism
- Disease Models, Animal
- Disease Progression
- Enzyme Activation
- Feasibility Studies
- Male
- Matrix Metalloproteinases/metabolism
- Mice, Inbred C57BL
- Mice, Transgenic
- Molecular Imaging/methods
- Multimodal Imaging
- Predictive Value of Tests
- Radiopharmaceuticals
- Risk Assessment
- Risk Factors
- Time Factors
- Tomography, Emission-Computed, Single-Photon
- Tomography, X-Ray Computed
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Affiliation(s)
- Reza Golestani
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Mahmoud Razavian
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Lei Nie
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Jiasheng Zhang
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Jae-Joon Jung
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Yunpeng Ye
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Michelle de Roo
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Koen Hilgerink
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Chi Liu
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Simon P Robinson
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.)
| | - Mehran M Sadeghi
- From the Section of Cardiovascular Medicine and Cardiovascular Research Center (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.), Department of Diagnostic Radiology (C.L.), Yale University School of Medicine, New Haven, CT; VA Connecticut Healthcare System, West Haven (R.G., M.R., L.N., J.Z., J.-J.J., Y.Y, M.d.R., K.H., M.M.S.); and Lantheus Medical Imaging, North Billerica, MA (S.P.R.).
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19
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Barwick TD, Lyons OTA, Mikhaeel NG, Waltham M, O’Doherty MJ. 18F-FDG PET-CT uptake is a feature of both normal diameter and aneurysmal aortic wall and is not related to aneurysm size. Eur J Nucl Med Mol Imaging 2014; 41:2310-8. [DOI: 10.1007/s00259-014-2865-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 07/13/2014] [Indexed: 01/10/2023]
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20
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Abstract
PURPOSE OF REVIEW Functional and molecular aortic imaging has shown great promise for evaluation of aortic disease, and may soon augment conventional assessment of aortic dimensions for the clinical management of patients. RECENT FINDINGS A range of imaging techniques is available for evaluation of patients with aortic disease. Magnetic resonance blood flow imaging can identify atherosclerosis prone aortic regions and may be useful for predicting aneurysm growth. Computational modeling can demonstrate significant differences in wall stress between abdominal aortic aneurysms of similar size and may better predict rupture than diameter alone. Metabolic imaging with fluorodeoxyglucose-PET [(FDG)-PET] can identify focal aortic wall inflammation that may portend rapid progression of disease. Molecular imaging with probes that target collagen and elastin can directly exhibit changes in the vessel wall associated with disease. SUMMARY The complexity of aortic disease is more fully revealed with new functional imaging techniques than with conventional anatomic analysis alone. This may better inform surveillance imaging regimens, medical management and decisions regarding early intervention for aortic disease.
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21
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Golestani R, Sadeghi MM. Emergence of molecular imaging of aortic aneurysm: implications for risk stratification and management. J Nucl Cardiol 2014; 21:251-67; quiz 268-70. [PMID: 24381115 PMCID: PMC3991015 DOI: 10.1007/s12350-013-9845-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 11/19/2013] [Indexed: 12/21/2022]
Abstract
Imaging cellular and molecular processes associated with aneurysm expansion, dissection, and rupture can potentially transform the management of patients with thoracic and abdominal aortic aneurysm. Here, we review recent advances in molecular imaging of aortic aneurysm, focusing on imaging modalities with the greatest potential for clinical translation and application, PET, SPECT, and MRI. Inflammation (e.g., with (18)F-FDG, nanoparticles) and matrix remodeling (e.g., with matrix metalloproteinase-targeted tracers) are highlighted as promising targets for molecular imaging of aneurysm. Potential alternative or complementary approaches to molecular imaging for aneurysm risk stratification are briefly discussed.
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Affiliation(s)
- Reza Golestani
- Cardiovascular Molecular Imaging Laboratory, Section of Cardiovascular Medicine and Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT, USA
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22
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Bonnard T, Yang G, Petiet A, Ollivier V, Haddad O, Arnaud D, Louedec L, Bachelet-Violette L, Derkaoui SM, Letourneur D, Chauvierre C, Visage CL. Abdominal aortic aneurysms targeted by functionalized polysaccharide microparticles: a new tool for SPECT imaging. Am J Cancer Res 2014; 4:592-603. [PMID: 24723981 PMCID: PMC3982130 DOI: 10.7150/thno.7757] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 12/16/2013] [Indexed: 02/02/2023] Open
Abstract
Aneurysm diagnostic is nowadays limited by the lack of technology that enables early detection and rupture risk prediction. New non invasive tools for molecular imaging are still required. In the present study, we present an innovative SPECT diagnostic tool for abdominal aortic aneurysm (AAA) produced from injectable polysaccharide microparticles radiolabeled with technetium 99m (99mTc) and functionalized with fucoidan, a sulfated polysaccharide with the ability to target P-Selectin. P-Selectin is a cell adhesion molecule expressed on activated endothelial cells and platelets which can be found in the thrombus of aneurysms, as well as in other vascular pathologies. Microparticles with a maximum hydrodynamic diameter of 4 µm were obtained by crosslinking the polysaccharides dextran and pullulan. They were functionalized with fucoidan. In vitro interactions with human activated platelets were assessed by flow cytometry that demonstrated a specific affinity of fucoidan functionalized microparticles for P-Selectin expressed by activated platelets. For in vivo AAA imaging, microparticles were radiolabeled with 99mTc and intravenously injected into healthy and AAA rats obtained by elastase perfusion through the aorta wall. Animals were scanned by SPECT imaging. A strong contrast enhancement located in the abdominal aorta of AAA rats was obtained, while no signal was obtained in healthy rats or in AAA rats after injection of non-functionalized control microparticles. Histological studies revealed that functionalized radiolabeled polysaccharide microparticles were localized in the AAA wall, in the same location where P-Selectin was expressed. These microparticles therefore constitute a promising SPECT imaging tool for AAA and potentially for other vascular diseases characterized by P-Selectin expression. Future work will focus on validating the efficiency of the microparticles to diagnose these other pathologies and the different stages of AAA. Incorporation of a therapeutic molecule is also considered.
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23
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Nchimi A, Cheramy-Bien JP, Gasser TC, Namur G, Gomez P, Seidel L, Albert A, Defraigne JO, Labropoulos N, Sakalihasan N. Multifactorial relationship between 18F-fluoro-deoxy-glucose positron emission tomography signaling and biomechanical properties in unruptured aortic aneurysms. Circ Cardiovasc Imaging 2013; 7:82-91. [PMID: 24190906 DOI: 10.1161/circimaging.112.000415] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND The relationship between biomechanical properties and biological activities in aortic aneurysms was investigated with finite element simulations and 18F-fluoro-deoxy-glucose (18F-FDG) positron emission tomography. METHODS AND RESULTS The study included 53 patients (45 men) with aortic aneurysms, 47 infrarenal (abdominal aortic) and 6 thoracic (thoracic aortic), who had ≥1 18F-FDG positron emission tomography/computed tomography. During a 30-month period, more clinical events occurred in patients with increased 18F-FDG uptake on their last examination than in those without (5 of 18 [28%] versus 2 of 35 [6%]; P=0.03). Wall stress and stress/strength index computed by finite element simulations and 18F-FDG uptake were evaluated in a total of 68 examinations. Twenty-five (38%) examinations demonstrated ≥1 aneurysm wall area of increased 18F-FDG uptake. The mean number of these areas per examination was 1.6 (18 of 11) in thoracic aortic aneurysms versus 0.25 (14 of 57) in abdominal aortic aneurysms, whereas the mean number of increased uptake areas colocalizing with highest wall stress and stress/strength index areas was 0.55 (6 of 11) and 0.02 (1 of 57), respectively. Quantitatively, 18F-FDG positron emission tomographic uptake correlated positively with both wall stress and stress/strength index (P<0.05). 18F-FDG uptake was particularly high in subjects with personal history of angina pectoris and familial aneurysm. CONCLUSIONS Increased 18F-FDG positron emission tomographic uptake in aortic aneurysms is strongly related to aneurysm location, wall stress as derived by finite element simulations, and patient risk factors such as acquired and inherited susceptibilities.
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MESH Headings
- Aged
- Aged, 80 and over
- Aortic Aneurysm, Abdominal/diagnostic imaging
- Aortic Aneurysm, Abdominal/etiology
- Aortic Aneurysm, Abdominal/physiopathology
- Aortic Aneurysm, Thoracic/diagnostic imaging
- Aortic Aneurysm, Thoracic/etiology
- Aortic Aneurysm, Thoracic/physiopathology
- Aortography/methods
- Biomechanical Phenomena
- Computer Simulation
- Female
- Finite Element Analysis
- Fluorodeoxyglucose F18
- Humans
- Linear Models
- Male
- Middle Aged
- Models, Cardiovascular
- Multimodal Imaging
- Positron-Emission Tomography
- Predictive Value of Tests
- Prognosis
- Radiopharmaceuticals
- Regional Blood Flow
- Risk Factors
- Stress, Mechanical
- Time Factors
- Tomography, X-Ray Computed
- Whole Body Imaging
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Affiliation(s)
- Alain Nchimi
- Departments of Cardiovascular and Thoracic Imaging
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Courtois A, Nusgens BV, Hustinx R, Namur G, Gomez P, Somja J, Defraigne JO, Delvenne P, Michel JB, Colige AC, Sakalihasan N. 18F-FDG Uptake Assessed by PET/CT in Abdominal Aortic Aneurysms Is Associated with Cellular and Molecular Alterations Prefacing Wall Deterioration and Rupture. J Nucl Med 2013; 54:1740-7. [DOI: 10.2967/jnumed.112.115873] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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25
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Martufi G, Christian Gasser T. Review: the role of biomechanical modeling in the rupture risk assessment for abdominal aortic aneurysms. J Biomech Eng 2013; 135:021010. [PMID: 23445055 DOI: 10.1115/1.4023254] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AAA disease is a serious condition and a multidisciplinary approach including biomechanics is needed to better understand and more effectively treat this disease. A rupture risk assessment is central to the management of AAA patients, and biomechanical simulation is a powerful tool to assist clinical decisions. Central to such a simulation approach is a need for robust and physiologically relevant models. Vascular tissue senses and responds actively to changes in its mechanical environment, a crucial tissue property that might also improve the biomechanical AAA rupture risk assessment. Specifically, constitutive modeling should not only focus on the (passive) interaction of structural components within the vascular wall, but also how cells dynamically maintain such a structure. In this article, after specifying the objectives of an AAA rupture risk assessment, the histology and mechanical properties of AAA tissue, with emphasis on the wall, are reviewed. Then a histomechanical constitutive description of the AAA wall is introduced that specifically accounts for collagen turnover. A test case simulation clearly emphasizes the need for constitutive descriptions that remodels with respect to the mechanical loading state. Finally, remarks regarding modeling of realistic clinical problems and possible future trends conclude the article.
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Affiliation(s)
- Giampaolo Martufi
- Department of Solid Mechanics, School of Engineering Sciences, Royal Institute of Technology (KTH), Osquars Backe 1, SE-100 44 Stockholm, Sweden.
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Kuivaniemi H, Sakalihasan N, Lederle FA, Jones GT, Defraigne JO, Labropoulos N, Legrand V, Michel JB, Nienaber C, Radermecker MA, Elefteriades JA. New Insights Into Aortic Diseases: A Report From the Third International Meeting on Aortic Diseases (IMAD3). AORTA (STAMFORD, CONN.) 2013; 1:23-39. [PMID: 26798669 PMCID: PMC4682695 DOI: 10.12945/j.aorta.2013.13.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 03/08/2013] [Indexed: 12/11/2022]
Abstract
The current state of research and treatment on aortic diseases was discussed in the "3rd International Meeting on Aortic Diseases" (IMAD3) held on October 4-6, 2012, in Liège, Belgium. The 3-day meeting covered a wide range of topics related to thoracic aortic aneurysms and dissections, abdominal aortic aneurysms, and valvular diseases. It brought together clinicians and basic scientists and provided an excellent opportunity to discuss future collaborative research projects for genetic, genomics, and biomarker studies, as well as clinical trials. Although great progress has been made in the past few years, there are still a large number of unsolved questions about aortic diseases. Obtaining answers to the key questions will require innovative, interdisciplinary approaches that integrate information from epidemiological, genetic, molecular biology, and bioengineering studies on humans and animal models. It is more evident than ever that multicenter collaborations are needed to accomplish these goals.
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Affiliation(s)
- Helena Kuivaniemi
- Sigfried and Janet Weis Center for Research, Geisinger Clinic, Danville, Pennsylvania
| | | | - Frank A. Lederle
- Minneapolis Center for Epidemiological and Clinical Research, Department of Medicine (III-0), VA Medical Center, Minneapolis, Minnesota
| | | | | | - Nicos Labropoulos
- Department of Surgery, Stony Brook University Medical Center, Stony Brook, New York
| | - Victor Legrand
- Cardiology Departments, University Hospital of Liège, CHU, Liège, Belgium
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Measuring and modeling patient-specific distributions of material properties in abdominal aortic aneurysm wall. Biomech Model Mechanobiol 2012; 12:717-33. [PMID: 22955570 DOI: 10.1007/s10237-012-0436-1] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 08/22/2012] [Indexed: 10/27/2022]
Abstract
Both the clinically established diameter criterion and novel approaches of computational finite element (FE) analyses for rupture risk stratification of abdominal aortic aneurysms (AAA) are based on assumptions of population-averaged, uniform material properties for the AAA wall. The presence of inter-patient and intra-patient variations in material properties is known, but has so far not been addressed sufficiently. In order to enable the preoperative estimation of patient-specific AAA wall properties in the future, we investigated the relationship between non-invasively assessable clinical parameters and experimentally measured AAA wall properties. We harvested n = 163 AAA wall specimens (n = 50 patients) during open surgery and recorded the exact excision sites. Specimens were tested for their thickness, elastic properties, and failure loads using uniaxial tensile tests. In addition, 43 non-invasively assessable patient-specific or specimen-specific parameters were obtained from recordings made during surgery and patient charts. Experimental results were correlated with the non-invasively assessable parameters and simple regression models were created to mathematically describe the relationships. Wall thickness was most significantly correlated with the metabolic activity at the excision site assessed by PET/CT (ρ = 0.499, P = 4 × 10(-7)) and to thrombocyte counts from laboratory blood analyses (ρ = 0.445, P = 3 × 10(-9)). Wall thickness was increased in patients suffering from diabetes mellitus, while it was significantly thinner in patients suffering from chronic kidney disease (CKD). Elastic AAA wall properties had significant correlations with the metabolic activity at the excision site (PET/CT), with existent calcifications, and with the diameter of the non-dilated aorta proximal to the AAA. Failure properties (wall strength and failure tension) had correlations with the patient's medical history and with results from laboratory blood analyses. Interestingly, AAA wall failure tension was significantly reduced for patients with CKD and elevated blood levels of potassium and urea, respectively, both of which are associated with kidney disease. This study is a first step to a future preoperative estimation of AAA wall properties. Results can be conveyed to both the diameter criterion and FE analyses to refine rupture risk prediction. The fact that AAA wall from patients suffering from CKD featured reduced failure tension implies an increased AAA rupture risk for this patient group at comparably smaller AAA diameters.
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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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Maier A, Essler M, Gee MW, Eckstein HH, Wall WA, Reeps C. Correlation of biomechanics to tissue reaction in aortic aneurysms assessed by finite elements and [18F]-fluorodeoxyglucose-PET/CT. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2012; 28:456-471. [PMID: 25365658 DOI: 10.1002/cnm.1477] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 08/24/2011] [Accepted: 09/14/2011] [Indexed: 06/04/2023]
Abstract
Mechanobiological interactions are essential for the adaption of the cardiovascular system to altered environmental and internal conditions, but are poorly understood with regard to abdominal aortic aneurysm (AAA) pathogenesis, growth and rupture. In the present study, we therefore calculated mechanical AAA quantities using nonlinear finite element methods and correlated these to [18F]-fluorodeoxyglucose (FDG)-metabolic activity in the AAA wall detected by positron emission tomography/computed tomography (PET/CT). The interplay between mechanics and FDG-metabolic activity was analyzed in terms of maximum values and the three-dimensional spatial relationship, respectively. Fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) data sets of n = 18 AAA patients were studied. Maximum FDG-uptake (SUV max ) in the AAA wall varied from 1.32 to 4.60 (average SUV max 3.31 ± 0.87). Maximum wall stresses and strains ranged from 10.0 to 64.0 N∕cm(2) (38.2 ± 13.8 N∕cm(2)) and from 0.190 to 0.260 (0.222 ± 0.023), respectively. SUV max was significantly correlated to maximum wall stress and strain (SUV max to stress: r = 0.71, p = 0.0005; SUV max to strain: r = 0.66, p = 0.0013). To evaluate the three-dimensional spatial interaction between FDG-uptake and acting wall stress, element-wise correlations were performed. In all but 2 AAAs, positive element-wise correlation of FDG-uptake to wall stress was obtained, with the Pearson's correlation coefficient ranging from -0.168 to 0.738 ( 0.372 ± 0.263). The results indicate that mechanical stresses are correlated quantitatively and spatially to FDG-uptake in the AAA wall. It is hypothesized that unphysiologically increased loading in the AAA wall triggers biological tissue reaction, such as inflammation or regenerative processes, causing elevated FDG-metabolic activity. These findings strongly support experimental hypotheses of mechanotransduction mechanisms in vivo.
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Affiliation(s)
- Andreas Maier
- Institute for Computational Mechanics, Technische Universit ät M ünchen, Boltzmannstr. 15, D-85747 Garching bei M ünchen, Germany
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Palombo D, Morbelli S, Spinella G, Pane B, Marini C, Rousas N, Massollo M, Cittadini G, Camellino D, Sambuceti G. A positron emission tomography/computed tomography (PET/CT) evaluation of asymptomatic abdominal aortic aneurysms: another point of view. Ann Vasc Surg 2011; 26:491-9. [PMID: 22197524 DOI: 10.1016/j.avsg.2011.05.038] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/05/2011] [Accepted: 05/27/2011] [Indexed: 11/19/2022]
Abstract
BACKGROUND To assess the prevalence of increased (18)F-fluorodeoxyglucose (FDG) uptake in aneurysmal walls, adopting a case-control approach in a population of asymptomatic patients with abdominal aortic aneurysm (AAA). METHODS This study included 40 males (mean age: 74 years, range: 59-93 years), consecutive, white Caucasian patients, with asymptomatic infrarenal AAA. The mean diameter of AAA was 4.9 cm (range: 4.8-5.4 cm), detected by computed tomography (CT) scan. Control Subjects: 44 age-matched controls subjects (mean age: 71 years, range: 59-85 years, 24 males, 20 females) who were selected according to a case-control criterion among a population of patients without any clinical evidence of atherosclerotic disease. Patients and controls underwent simultaneous FDG-positron emission tomography (PET) and CT imaging from the skull base to the femoral neck by using an integrated PET/CT scanner. PET/CT studies were analysed both visually and quantitatively. For quantitative analysis, circular CT-based regions of interest (ROIs) were drawn on the AAA, on all the aortic segments, and on the large vessel included in the study (carotid, subclavian, and iliac arteries). FDG uptake was quantified by calculating the mean and maximum standardized uptake values (SUVs) within each ROI and normalizing for the blood-pool SUV to obtain the final target-to-background ratio. Arterial calcium load was graded according to a semiquantitative five-point scale based on calcification of the arterial ring. RESULTS Metabolic activity in the aneurysmal aortic segment was even lower with respect to both the adjacent--nonaneurysmal--samples of patient group and the corresponding arterial segments of control subjects (P < 0.001 and P < 0.01, respectively). In visual analysis, no patients showed an increased focal uptake of degree adequate to identify the aneurysmal arterial wall. AAA patients showed significantly higher values of total calcium load (ACL) than controls in ascending aorta and subclavian and iliac arteries (P < 0.01), and only in AAA patient group, a significant correlation was present between values of ACL in both iliac arteries and abdominal aorta on one side and wall metabolic activity in the same arteries on the other (P < 0.05). CONCLUSIONS In conclusion, our results suggest that FDG hot spot, as well an increased diffuse uptake of FDG, in PET/CT studies is an extremely rare finding in patients with AAA of diameter close to surgical indications.
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Affiliation(s)
- Domenico Palombo
- Division of Vascular and Endovascular Surgery, IRCCS San Martino University Hospital-IST, University of Genoa, Genoa, Italy
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Direct relationship between cell density and FDG uptake in asymptomatic aortic aneurysm close to surgical threshold: an in vivo and in vitro study. Eur J Nucl Med Mol Imaging 2011; 39:91-101. [PMID: 22012546 DOI: 10.1007/s00259-011-1955-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Accepted: 09/27/2011] [Indexed: 10/16/2022]
Abstract
PURPOSE Conflicting results have been reported about the clinical value of fluorodeoxyglucose (FDG) imaging in predicting the risk of rupture of abdominal aortic aneurysm (AAA). The present study tests the hypothesis that FDG uptake is low in asymptomatic noninflammatory AAA due to the low cell density in aneurysmal walls. METHODS Positron emission tomography (PET)/CT imaging was performed in 12 consecutive candidates for AAA surgical repair and in 12 age- and sex-matched controls. At intervention, aneurysmal walls were cut into three sequential blocks. Block A was frozen to cut three 5-μm slices for incubation with 2-3 MBq of FDG for 5 min. Block C was first incubated with the same tracer solution for the same time and subsequently frozen to cut three 5-μm slices. Autoradiographic images were coregistered with immunohistochemical pictures of cell density, type and DNA synthesis as assessed on block B. RESULTS No visible uptake in abdominal aorta occurred in any patient or control subject. Immunohistochemistry documented a severe loss of wall structure, with low numbers of cells. Tracer retention directly correlated with overall cell density and with prevalence of cells synthesizing DNA. The metabolic nature of FDG uptake was confirmed by the selective effect of preliminary freezing that decreased tracer content by 90% in regions with high cell density and only by 34% in cold acellular areas. CONCLUSION The loss of tissue structure and the marked decrease in cell density account for the low prevalence of positive findings at FDG PET imaging, at least in asymptomatic patients bearing AAAs whose diameter is close to surgical indication.
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What is the relationship between ¹⁸F-FDG aortic aneurysm uptake on PET/CT and future growth rate? Eur J Nucl Med Mol Imaging 2011; 38:1493-9. [PMID: 21468762 DOI: 10.1007/s00259-011-1799-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Accepted: 03/09/2011] [Indexed: 10/18/2022]
Abstract
PURPOSE In this study we investigate the relationship between (18)F-fluorodeoxyglucose (FDG) metabolism and future aneurysm expansion measured by serial duplex ultrasound. Current screening programmes are increasing the identification of patients with abdominal aortic aneurysm (AAA). The management of these patients remains challenging and methods of risk stratification are sought. METHODS Thirty-four consecutive patients [31 men, 3 women, median age 75 years, interquartile range (IQR) 71-78] with aortic aneurysms under routine surveillance with serial ultrasound were prospectively recruited for (18)F-FDG positron emission tomography (PET)/CT. A whole vessel type analysis was performed measuring the highest aortic wall (18)F-FDG uptake (standardized uptake value or SUV(max)), and target to background ratio (TBR) for each axial image and median SUV(max) and TBR value were calculated. Institutional Review Board permission and informed patient consent were obtained. RESULTS Nine patients failed to undergo 12-month follow-up study (deceased n = 2, withdrew n = 1, failed to attend ultrasound scan n = 5, emergency aneurysm repair n = 1) leaving 25 patients for analysis. The median whole vessel SUV(max) was 1.70 (IQR 1.45-2.08). The median whole vessel TBR was 1.15 (IQR 1.00-1.40). The median aneurysm expansion at 12 months was 2.0 mm (IQR 0.5-5.0). The correlation (r) between (18)F-FDG SUV(max) and ultrasound expansion at 1 year was -0.501 (p = 0.011). CONCLUSION The preliminary findings from this observational longitudinal pilot study suggest that there is an inverse trend between (18)F-FDG uptake on PET and future AAA expansion. Aortic aneurysms with lower metabolic activity may therefore be more likely to expand.
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Hong H, Yang Y, Liu B, Cai W. Imaging of Abdominal Aortic Aneurysm: the present and the future. Curr Vasc Pharmacol 2011; 8:808-19. [PMID: 20180767 DOI: 10.2174/157016110793563898] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 01/07/2010] [Indexed: 01/02/2023]
Abstract
Abdominal Aortic Aneurysm (AAA) is a common, progressive, and potentially lethal vascular disease. A major obstacle in AAA research, as well as patient care, is the lack of technology that enables non-invasive acquisition of molecular/cellular information in the developing AAA. In this review we will briefly summarize the current techniques (e.g. ultrasound, computed tomography, and magnetic resonance imaging) for anatomical imaging of AAA. We also discuss the various functional imaging techniques that have been explored for AAA imaging. In many cases, these anatomical and functional imaging techniques are not sufficient for providing surgeons/clinicians enough information about each individual AAA (e.g. rupture risk) to optimize patient management. Recently, molecular imaging techniques (e.g. optical and radionuclide-based) have been employed to visualize the molecular alterations associated with AAA, which are discussed in this review. Lastly, we try to provide a glance into the future and point out the challenges for AAA imaging. We believe that the future of AAA imaging lies in the combination of anatomical and molecular imaging techniques, which are largely complementary rather than competitive. Ultimately, with the right molecular imaging probe, clinicians will be able to monitor AAA growth and evaluate the risk of rupture accurately, so that the life-saving surgery can be provided to the right patients at the right time. Equally important, the right imaging probe will also allow scientists/clinicians to acquire critical data during AAA development and to more accurately evaluate the efficacy of potential treatments.
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Affiliation(s)
- Hao Hong
- Department of Radiology, School of Medicine and Public Health, University of Wisconsin - Madison, Madison, WI 53705-2275, USA
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Grond-Ginsbach C, Pjontek R, Aksay SS, Hyhlik-Dürr A, Böckler D, Gross-Weissmann ML. Spontaneous arterial dissection: phenotype and molecular pathogenesis. Cell Mol Life Sci 2010; 67:1799-815. [PMID: 20155481 PMCID: PMC11115591 DOI: 10.1007/s00018-010-0276-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 12/08/2009] [Accepted: 01/15/2010] [Indexed: 12/22/2022]
Abstract
Arterial dissection (AD) is defined as the longitudinal splitting up of the arterial wall caused by intramural bleeding. It can occur as a spontaneous event in all large and medium sized arteries. The histological hallmark of AD is medial degeneration. Histological investigations, gene expression profiling and proteome studies of affected arteries reveal disturbances in many different biological processes including inflammation, proteolytic activity, cell proliferation, apoptosis and smooth muscle cell (SMC) contractile function. Medial degeneration can be caused by various rare dominant Mendelian disorders. Genetic linkage analysis lead to the identification of mutations in different disease-causing genes involved in the biosynthesis of the extracellular matrix (FBN1, COL3A1), in transforming growth factor (TGF) beta signaling (FBN1, TGFBR1, TGFBR2) and in the SMC contractile system (ACTA2, MYH11). Genome wide association studies suggest that the CDKN2A/CDKN2B locus plays a role in the etiology AD and other arterial diseases.
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Wiernicki I, Stachowska E, Safranow K, Cnotliwy M, Rybicka M, Kaczmarczyk M, Gutowski P. Enhanced matrix-degrading proteolytic activity within the thin thrombus-covered wall of human abdominal aortic aneurysms. Atherosclerosis 2010; 212:161-5. [PMID: 20537648 DOI: 10.1016/j.atherosclerosis.2010.04.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 04/23/2010] [Accepted: 04/26/2010] [Indexed: 10/19/2022]
Abstract
OBJECTIVE The maintenance of an arterial elastin's integrity is essential in the prevention of abdominal aortic aneurysm (AAA) development. So far, the effect of intraluminal thrombus (ILT) thickness on the elastolytic activity within the AAA wall has not been studied. In the present study the hypothesis that thin thrombus is associated with enhanced proteolytic activity within human AAA wall was investigated. METHODS The specimens for analysis, from both thin (< or = 10 mm) thrombus-covered and thick (> or = 25 mm) thrombus-covered wall, had been taken from 40 patients undergoing elective repair of AAA. We evaluated neutrophil elastase activity with the enzymatic assay. Concentrations of active matrix metalloproteinase-9 (MMP-9), total matrix metalloproteinase-8 (MMP-8), and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) were measured by ELISA. Biochemical parameters were compared with the Wilcoxon signed-rank test. RESULTS Statistical analysis showed that the activity of elastase (P<0.0001) as well as concentrations of active MMP-9 (P=0.001), total MMP-8 (P<0.0001) and active MMP-9/total TIMP-1 ratio (P=0.002) were significantly higher in the thin thrombus-covered wall. Furthermore the TIMP-1 was found to have a lower concentration in the thin thrombus-covered in comparison with the thick thrombus-covered wall (P=0.003). There was a significant positive correlation between measurements in AAA wall sites with thin and thick thrombus for elastase, TIMP-1, MMP-9/TIMP-1 ratio, and a borderline correlation was observed for MMP-8. Active MMP-9 concentration did not correlate between sites. CONCLUSION The current study demonstrates the differentiation of protease activity within the same AAA wall and its enhancement within the thin thrombus-covered aneurysm wall.
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Affiliation(s)
- Ireneusz Wiernicki
- Department of Vascular Surgery and Angiology, Pomeranian Medical University, Powstancow Wielkopolskich 72, 70-111 Szczecin, Poland.
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Reeps C, Pelisek J, Bundschuh RA, Gurdan M, Zimmermann A, Ockert S, Dobritz M, Eckstein HH, Essler M. Imaging of Acute and Chronic Aortic Dissection by 18F-FDG PET/CT. J Nucl Med 2010; 51:686-91. [DOI: 10.2967/jnumed.109.072298] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Paraskevas KI, Tzovaras AA, Stathopoulos V, Gentimi F, Mikhailidis DP. Increased fluorodeoxyglucose uptake following endovascular abdominal aortic aneurysm repair: a predictor of endoleak? Open Cardiovasc Med J 2010; 4:117-9. [PMID: 20657717 PMCID: PMC2908925 DOI: 10.2174/1874192401004010117] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 03/09/2010] [Accepted: 03/11/2010] [Indexed: 11/22/2022] Open
Abstract
The main criterion for abdominal aortic aneurysm (AAA) repair is an AAA diameter ≥5.5 cm. However, some AAAs rupture when they are smaller. Size alone may therefore not be a sufficient criterion to determine rupture risk. Fluorodeoxyglucose (FDG) uptake is increased in the presence of inflammation and it was suggested that this may be a better predictor of rupture risk than AAA size. Furthermore, increased FDG uptake following endovascular AAA repair may be an indirect predictor of continuous AAA sac enlargement due to the presence of an endoleak (even if this is not detected by imaging modalities) and/or increased AAA rupture risk. The role of FDG uptake needs to be explored further in the management of AAAs.
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Abstract
PURPOSE OF REVIEW Abdominal aortic aneurysm (AAA) is being diagnosed more frequently in older patients due to the increased use of abdominal imaging and the rising average age of western populations. Currently the management of this condition has two important deficiencies: inadequate methods to identify AAAs at risk of progression and rupture and the current lack of effective nonsurgical therapies. In this review recent developments in identifying new diagnostic, prognostic and therapeutic strategies for AAA are discussed. RECENT FINDINGS There are growing number of animal and human association studies which have identified markers and strategies of potential value in improving identification, monitoring and treatment of AAA. SUMMARY Selective large prospective imaging, biomarker and intervention studies are now required to clearly demonstrate the value of new management pathways for AAA.
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Paraskevas KI, Tzovaras AA, Gentimi F, Kyriakides ZS, Mikhailidis DP. Predictors of Abdominal Aortic Aneurysm (AAA) Growth and AAA Rupture Risk Besides AAA Size: Fact or Fiction? Angiology 2010; 61:321-3. [DOI: 10.1177/0003319709360526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | | | - Fotini Gentimi
- 2nd Department of Pediatric Surgery, Aghia Sophia Children's Hospital, Athens, Greece
| | | | - Dimitri P. Mikhailidis
- Department of Clinical Biochemistry (Vascular Disease Prevention Clinics), Royal Free Hospital Campus, University College London Medical School, University College London (UCL), London, UK
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Paraskevas KI. Regarding "Increased 18F-fluorodeoxyglucose uptake in abdominal aortic aneurysms in positron emission/computed tomography is associated with inflammation, aortic wall instability, and acute symptoms". J Vasc Surg 2009; 49:1631; author reply 1631-2. [PMID: 19497529 DOI: 10.1016/j.jvs.2008.08.093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2008] [Revised: 08/19/2008] [Accepted: 08/19/2008] [Indexed: 10/20/2022]
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Orta Kilickesmez K, Kilickesmez O. Clear Depiction of Inflammatory Abdominal Aortic Aneurysm with Diffusion-Weighted Magnetic Resonance Imaging. Cardiovasc Intervent Radiol 2009; 33:379-82. [DOI: 10.1007/s00270-009-9528-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2008] [Revised: 01/21/2009] [Accepted: 01/22/2009] [Indexed: 11/28/2022]
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Kotze CW, Menezes LJ, Endozo R, Groves AM, Ell PJ, Yusuf SW. Increased metabolic activity in abdominal aortic aneurysm detected by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT). Eur J Vasc Endovasc Surg 2009; 38:93-9. [PMID: 19217326 DOI: 10.1016/j.ejvs.2008.12.016] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Accepted: 12/10/2008] [Indexed: 11/18/2022]
Abstract
OBJECTIVES Abdominal aortic aneurysms (AAAs) are associated with an inflammatory cell infiltrate and enzymatic degradation of the vessel wall. The aim of this study was to detect increased metabolic activity in the wall of the AAA with 18F-fluorodeoxyglucose ((18)F-FDG), mediated by glucose transporter protein (GLUTs), using a dedicated hybrid PET/64-detector CT. DESIGN, METHOD AND MATERIALS: 14 patients (All male, mean age 73.6 years, range 61-82) with AAA under surveillance underwent PET/CT scanning with 175 MBq of intravenous (18)F-FDG. The maximum aneurysm diameter and calcification score were determined on the attenuation correction CT. A volume of interest was placed on the aneurysm sac and the maximum Standardised Uptake Value (SUV(max)) measured. RESULTS The mean aneurysm diameter was 5.4 cm (SD+/-0.8). Two aneurysms had the CT characteristics of inflammatory aneurysms. Twelve aneurysms showed increased FDG uptake (SUV(max)>2.5). There was no significant difference in FDG uptake between heavily calcified aneurysms and non-heavily calcified aneurysms (t-test). There was a significant increase in the FDG uptake in the two inflammatory aneurysms compared to the other twelve aneurysms (t-test; P=0.04). CONCLUSION The findings in this study offer in vivo evidence that the AAA wall shows increased glucose metabolism, mediated by the GLUTs: this increased metabolic activity as detected by PET/CT may be present in most AAAs.
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Affiliation(s)
- C W Kotze
- Department of Vascular Surgery, Brighton & Sussex University Hospitals NHS Trust, Brighton, East Sussex, UK.
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Zimmerman PM, Cherr GS, Angelos GC, Gona J, Dosluoglu HH. Is F 18 Fluorodeoxyglucose Positron Emission Tomography Too Sensitive for the Diagnosis of Vascular Endograft Infection? Vascular 2008; 16:346-9. [DOI: 10.2310/6670.2008.00049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We report a case of a false positive fluorodeoxyglucose positron emission tomography (FDG-PET) scan in a patient who presented with abdominal pain, and gastrointestinal bleeding accompanied by elevation of inflammatory markers, seven weeks after a proximal type I endoleak repair with a cuff extension. Aortoenteric fistula and endograft infection was ruled out by laparotomy. FDG-PET image may have a role in diagnosis of infection, but false positive results are possible and caution is necessary if other data are non-confirmatory.
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Affiliation(s)
- Pamela M. Zimmerman
- *Division of Vascular and Endovascular Surgery, West Virginia University, Morgantown, WV; †Division of Vascular Surgery, Department of Surgery, ‡School of Medicine, and §Department of Nuclear Medicine, State University of New York at Buffalo, Buffalo, NY; ‖VA Western New York Healthcare System, Buffalo, NY
| | - Gregory S. Cherr
- *Division of Vascular and Endovascular Surgery, West Virginia University, Morgantown, WV; †Division of Vascular Surgery, Department of Surgery, ‡School of Medicine, and §Department of Nuclear Medicine, State University of New York at Buffalo, Buffalo, NY; ‖VA Western New York Healthcare System, Buffalo, NY
| | - George C. Angelos
- *Division of Vascular and Endovascular Surgery, West Virginia University, Morgantown, WV; †Division of Vascular Surgery, Department of Surgery, ‡School of Medicine, and §Department of Nuclear Medicine, State University of New York at Buffalo, Buffalo, NY; ‖VA Western New York Healthcare System, Buffalo, NY
| | - Jayakumari Gona
- *Division of Vascular and Endovascular Surgery, West Virginia University, Morgantown, WV; †Division of Vascular Surgery, Department of Surgery, ‡School of Medicine, and §Department of Nuclear Medicine, State University of New York at Buffalo, Buffalo, NY; ‖VA Western New York Healthcare System, Buffalo, NY
| | - Hasan H. Dosluoglu
- *Division of Vascular and Endovascular Surgery, West Virginia University, Morgantown, WV; †Division of Vascular Surgery, Department of Surgery, ‡School of Medicine, and §Department of Nuclear Medicine, State University of New York at Buffalo, Buffalo, NY; ‖VA Western New York Healthcare System, Buffalo, NY
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Truijers M, Kurvers HAJM, Bredie SJH, Oyen WJG, Blankensteijn JD. In vivo imaging of abdominal aortic aneurysms: increased FDG uptake suggests inflammation in the aneurysm wall. J Endovasc Ther 2008; 15:462-7. [PMID: 18729562 DOI: 10.1583/08-2447.1] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE To study the potential of integrated positron emission tomography and computed tomography (PET/CT) to identify aneurysm wall inflammation. METHODS The level of F18-fluorodeoxyglucose (FDG) uptake was studied in aneurysmal and normal-sized aortas of 34 male patients [17 with abdominal aortic aneurysm (AAA) and 17 age-matched controls] identified in a database of 278 consecutive patients evaluated for staging of primary lung cancer. The maximal standardized uptake value (SUV) was calculated to quantify FDG uptake in the AAA wall. RESULTS AAAs showed significantly higher FDG uptake than the normal-sized aorta in age-matched controls (SUV 2.52+/-0.52 versus 1.78+/-0.45, respectively; p<0.001). The level of FDG uptake did not correlate with maximal aneurysm diameter (r=0.09; 95% CI -0.42 to 0.56; p=0.7). CONCLUSION FDG-PET/CT is a promising technique to identify inflammation of the aneurysm wall. Irrespective of aneurysm diameter, asymptomatic AAAs show more FDG uptake and more inflammatory activity in the wall than the non-dilated abdominal aorta of sex/age-matched controls. Future studies will be directed at the predictive value of increased FDG uptake for aneurysm wall strength, rupture risk, and the utility of FDG-PET/CT in assessing the effect of medical interventions.
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Affiliation(s)
- Maarten Truijers
- Department of Vascular Surgery, Radboud University Nijmegen Medical Centre, The Netherlands.
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Bonekamp D, Smith JD, Aygun N. Avid FDG uptake in a rapidly enlarging common carotid artery mycotic aneurysm, mimicking lymphadenopathy. Emerg Radiol 2008; 16:383-6. [PMID: 19002508 DOI: 10.1007/s10140-008-0778-2] [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] [Received: 10/07/2008] [Accepted: 10/22/2008] [Indexed: 11/26/2022]
Abstract
We present a case of mycotic pseudoaneurysm of the right common carotid artery, which demonstrated avid FDG uptake mimicking lymphomatous involvement on a non-contrast FDG-PET/CT scan. Within 6 days of initial presentation, the pseudoaneurysm enlarged rapidly and required emergent surgical repair. To the best of our knowledge, this is the first reported case both of a PET-positive non-aortic aneurysm and a rapidly enlarging common carotid artery pseudoaneurysm. This case highlights the importance of contrast administration with PET/CT and the heralding nature of FDG uptake in an aneurysm wall for impending aneurysm rupture.
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Affiliation(s)
- David Bonekamp
- Department of Radiology, The Johns Hopkins Hospital, Baltimore, MD 21287, USA.
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Abstract
A 71-year-old white man with a known right-sided apical nonsmall cell lung carcinoma was referred for a F-18 FDG whole body PET-CT examination after chemotherapy before radiotherapy. A staging CT scan had revealed an asymptomatic fusiform 65 mm in diameter nondissecting aneurysm of the thoracic aorta just below the carina. An abnormal crescent-shaped uptake was identified at the margin between the aneurysm and the adjacent thoracic vertebral bodies. At this site a correspondingly shaped bone erosion on CT was proof of the chronic effects of the aneurysm. There were no signs of regional inflammation or malignancy. The FDG uptake was interpreted as evidence of ongoing nonmalignant bone remodeling secondary to the pulsating pressure of the aneurysm. This case demonstrates a potential pitfall in the interpretation of bone associated foci using FDG PET, and once again underlines the importance of correlated anatomic imaging for appropriate clinical management.
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F-18 FDG PET/CT in the Management of Infected Abdominal Aortic Aneurysm Due To Salmonella. Clin Nucl Med 2008; 33:492-5. [DOI: 10.1097/rlu.0b013e31817793a0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Reeps C, Essler M, Pelisek J, Seidl S, Eckstein HH, Krause BJ. Increased 18F-fluorodeoxyglucose uptake in abdominal aortic aneurysms in positron emission/computed tomography is associated with inflammation, aortic wall instability, and acute symptoms. J Vasc Surg 2008; 48:417-23; discussion 424. [PMID: 18572354 DOI: 10.1016/j.jvs.2008.03.059] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 03/03/2008] [Accepted: 03/16/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE With the established computed tomographic (CT)- morphologic parameters, only the relative, but not the individual rupture risk of abdominal aortic aneurysm (AAA), can be determined. So far, increased aortic 18F-fluorodeoxyglucose (FDG) metabolism measured by positron emission tomography (PET) has been reported in AAA with increased rupture risk. The aim of the study was to analyze the histopathologic changes in AAA wall correlated with increased FDG uptake for further implications on aortic wall stability and AAA rupture risk. METHODS Fifteen patients with asymptomatic (n = 12) and symptomatic (n = 3) AAA underwent FDG-PET/CT, followed by open AAA repair. FDG-PET/CT was used for precise localization of maximum FDG uptake, and the maximum standard uptake values (SUV(max)) were calculated. Biopsies of the AAA wall were operatively collected from areas with maximum FDG uptake, immunohistologically stained, and semiquantitatively analyzed for inflammatory infiltrates, vascular smooth muscle cells (VSMC), matrix metalloproteinase (MMP)-2 and -9 expression, as well as for elastin and collagenous fibers. RESULTS Symptomatic AAA showed significantly increased FDG uptake compared with asymptomatic AAA (SUV(max), 3.5 +/- 0.6 vs 7.5 +/- 3; P < .001). Thus, increased FDG uptake was correlated with higher densities of inflammatory infiltrates (r = +0.87, P < .01) and macrophage and T-cell infiltrations (r = +0.95, P < .01 and r = +0.66, P < .05), with higher MMP-9 expressions (r = +0.86; P < .01), and with reduction of collagen fiber (r = -0.76; P < .01) and VSMCs (r = -0.71; P < .01). Consecutive correlations were found for total inflammatory infiltrates, T lymphocytes, and macrophages with MMP-9 expression (r = +0.79, +0.79 and +0.74; P < .01). Moreover, MMP-9 expression was correlated with decreasing collagen fiber content (r = -0.53, P < .05) and VSMC density (r = -0.57, P < .05). CONCLUSIONS Maximum aortic FDG uptake correlated significantly with inflammation, followed by increased MMP expression and histopathologic characteristics of aneurysm wall instability and clinical symptoms. Therefore, FDG-PET/CT might be a new diagnostic technique to study AAA disease in vivo and may contribute to improve prediction of individual AAA rupture risk.
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Affiliation(s)
- Christian Reeps
- Department of Vascular Surgery, University Hospital rechts der Isar, Technical University of Munich, Munich, Germany.
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Abstract
We present the case of a 62-year-old patient with a history of non-Hodgkin lymphoma (stage III) in complete remission after 6 cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone with rituximab (CHOP-R) in 2006. The patient was referred for a PET-CT scan because of suspicion of recurrence. On PET there were multiple lung lesions, a submandibular lesion (right side) and an impressive retroperitoneal mass with a hypermetabolic wall, and central necrosis invading all retroperitoneal structures (aorta). There was also an additional lesion in the anterior abdominal wall below the liver. It was concluded that it was recurrent non-Hodgkin lymphoma (stage IV). Contrast enhanced CT demonstrated a large, rupturing abdominal aortic aneurysm (AAA) with saccular ectasia of the posterior wall compatible with a mycotic aneurysm. The other sites of hypermetabolism corresponded to metastatic infectious lesions. Histopathology confirmed the mycotic infection. The patient underwent urgent surgery including bilateral axillofemoral stenting and removing a clot from the AAA twice. Intravenous antibiotics were started. This case clearly denotes the importance of contrast enhanced hybrid PET-CT systems in which the CT information is relevant for PET interpretation and not only for anatomic repair. With PET alone, the diagnosis would have been completely different.
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van der Vaart MG, Meerwaldt R, Slart RHJA, van Dam GM, Tio RA, Zeebregts CJ. Application of PET/SPECT imaging in vascular disease. Eur J Vasc Endovasc Surg 2008; 35:507-13. [PMID: 18180182 DOI: 10.1016/j.ejvs.2007.11.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2007] [Accepted: 11/27/2007] [Indexed: 12/26/2022]
Abstract
BACKGROUND Nuclear medicine imaging differs from other imaging modalities by showing physiological processes instead of anatomical details. OBJECTIVE To describe the current applications of positron emission tomography (PET) and single photon emission computed tomography (SPECT) as a diagnostic tool for vascular disease as relevant to vascular surgeons. METHODS A literature search identified articles focussing on vascular disease and PET or SPECT using the Pubmed database. Manual cross referencing was also performed. RESULTS PET and SPECT may be used to assess plaque vulnerability, biology of aneurysm progression, prosthetic graft infection, and vasculitis. The ability to combine computerized tomography scanning or magnetic resonance imaging with PET or SPECT adds detailed anatomical information and enhances the potential of nuclear medicine imaging in the investigation of vascular disease. DISCUSSION Considerable further information will be needed to define whether and where PET or SPECT will fit in a clinical strategy. The necessary validation studies represent an exciting challenge for the future but also may require the development of interdisciplinary imaging groups to integrate expertise and optimize nuclear diagnostic potential.
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Affiliation(s)
- M G van der Vaart
- Department of Surgery, University Medical Center Groningen, Groningen, The Netherlands
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