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Fernández-Martínez D, González-Fernández MR, Nogales-Asensio JM, Ferrera C. Impact of minimal lumen segmentation uncertainty on patient-specific coronary simulations: A look at FFR CT. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2024; 40:e3822. [PMID: 38566253 DOI: 10.1002/cnm.3822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/20/2024] [Accepted: 03/24/2024] [Indexed: 04/04/2024]
Abstract
We examined the effect of minimal lumen segmentation uncertainty on Fractional Flow Reserve obtained from Coronary Computed Tomography AngiographyFFR CT . A total of 14 patient-specific coronary models with different stenosis locations and degrees of severity were enrolled in this study. The optimal segmented coronary lumens were disturbed using intra± 6 % and inter-operator± 15 % variations on the segmentation threshold.FFR CT was evaluated in each case by 3D-OD CFD simulations. The findings suggest that the sensitivity ofFFR CT to this type of uncertainty increases distally and with the stenosis severity. Cases with moderate or severe distal coronary lesions should undergo either exact and thorough segmentation operations or invasive FFR measurements, particularly if theFFR CT is close to the cutoff (0.80). Therefore, we conclude that it is crucial to consider the lesion's location and degree of severity when evaluatingFFR CT results.
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Affiliation(s)
- Daniel Fernández-Martínez
- Departamento de Ingeniería Mecánica, Energética y de los Materiales, Universidad de Extremadura, Badajoz, Spain
| | | | | | - Conrado Ferrera
- Departamento de Ingeniería Mecánica, Energética y de los Materiales, Universidad de Extremadura, Badajoz, Spain
- Instituto de Computación Científica Avanzada, Universidad de Extremadura, Badajoz, Spain
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2
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Liu B, Su L, Loo SJ, Gao Y, Khin E, Kong X, Dalan R, Su X, Lee KO, Ma J, Ye L. Matrix metallopeptidase 9 contributes to the beginning of plaque and is a potential biomarker for the early identification of atherosclerosis in asymptomatic patients with diabetes. Front Endocrinol (Lausanne) 2024; 15:1369369. [PMID: 38660518 PMCID: PMC11039961 DOI: 10.3389/fendo.2024.1369369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/22/2024] [Indexed: 04/26/2024] Open
Abstract
AIMS To determine the roles of matrix metallopeptidase-9 (MMP9) on human coronary artery smooth muscle cells (HCASMCs) in vitro, early beginning of atherosclerosis in vivo in diabetic mice, and drug naïve patients with diabetes. METHODS Active human MMP9 (act-hMMP9) was added to HCASMCs and the expressions of MCP-1, ICAM-1, and VCAM-1 were measured. Act-hMMP9 (n=16) or placebo (n=15) was administered to diabetic KK.Cg-Ay/J (KK) mice. Carotid artery inflammation and atherosclerosis measurements were made at 2 and 10 weeks after treatment. An observational study of newly diagnosed drug naïve patients with type 2 diabetes mellitus (T2DM n=234) and healthy matched controls (n=41) was performed and patients had ultrasound of carotid arteries and some had coronary computed tomography angiogram for the assessment of atherosclerosis. Serum MMP9 was measured and its correlation with carotid artery or coronary artery plaques was determined. RESULTS In vitro, act-hMMP9 increased gene and protein expressions of MCP-1, ICAM-1, VCAM-1, and enhanced macrophage adhesion. Exogenous act-hMMP9 increased inflammation and initiated atherosclerosis in KK mice at 2 and 10 weeks: increased vessel wall thickness, lipid accumulation, and Galectin-3+ macrophage infiltration into the carotid arteries. In newly diagnosed T2DM patients, serum MMP9 correlated with carotid artery plaque size with a possible threshold cutoff point. In addition, serum MMP9 correlated with number of mixed plaques and grade of lumen stenosis in coronary arteries of patients with drug naïve T2DM. CONCLUSION MMP9 may contribute to the initiation of atherosclerosis and may be a potential biomarker for the early identification of atherosclerosis in patients with diabetes. CLINICAL TRIAL REGISTRATION https://clinicaltrials.gov, identifier NCT04424706.
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Affiliation(s)
- Bingli Liu
- Department of Endocrinology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Liping Su
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
| | - Sze Jie Loo
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
| | - Yu Gao
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
- Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ester Khin
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
| | - Xiaocen Kong
- Department of Endocrinology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Rinkoo Dalan
- Department of Endocrinology, Tan Tock Seng Hospital Lee Kong Chian School of Medicine Nanyang Technological University Singapore, Singapore, Singapore
| | - Xiaofei Su
- Department of Endocrinology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Kok-Onn Lee
- Division of Endocrinology, Department of Medicine, National University of Singapore, Singapore, Singapore
| | - Jianhua Ma
- Department of Endocrinology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Lei Ye
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
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Recent Trends in Artificial Intelligence-Assisted Coronary Atherosclerotic Plaque Characterization. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph181910003. [PMID: 34639303 PMCID: PMC8508413 DOI: 10.3390/ijerph181910003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/12/2021] [Accepted: 09/17/2021] [Indexed: 01/21/2023]
Abstract
Coronary artery disease is a major cause of morbidity and mortality worldwide. Its underlying histopathology is the atherosclerotic plaque, which comprises lipid, fibrous and—when chronic—calcium components. Intravascular ultrasound (IVUS) and intravascular optical coherence tomography (IVOCT) performed during invasive coronary angiography are reference standards for characterizing the atherosclerotic plaque. Fine image spatial resolution attainable with contemporary coronary computed tomographic angiography (CCTA) has enabled noninvasive plaque assessment, including identifying features associated with vulnerable plaques known to presage acute coronary events. Manual interpretation of IVUS, IVOCT and CCTA images demands scarce physician expertise and high time cost. This has motivated recent research into and development of artificial intelligence (AI)-assisted methods for image processing, feature extraction, plaque identification and characterization. We performed parallel searches of the medical and technical literature from 1995 to 2021 focusing respectively on human plaque characterization using various imaging modalities and the use of AI-assisted computer aided diagnosis (CAD) to detect and classify atherosclerotic plaques, including their composition and the presence of high-risk features denoting vulnerable plaques. A total of 122 publications were selected for evaluation and the analysis was summarized in terms of data sources, methods—machine versus deep learning—and performance metrics. Trends in AI-assisted plaque characterization are detailed and prospective research challenges discussed. Future directions for the development of accurate and efficient CAD systems to characterize plaque noninvasively using CCTA are proposed.
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4
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Higashi M, Yamada N, Imakita S, Yutani C, Ishibashi-Ueda H, Iihara K, Naito H. CT-pathologic correlation of non-calcified atherosclerotic arterial plaques: a study using carotid endarterectomy specimens. Br J Radiol 2020; 93:20190901. [PMID: 31999208 DOI: 10.1259/bjr.20190901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Pathologic features of atherosclerotic plaques on CT are not established. We compared CT values among pathologically confirmed plaque constituents and evaluated their ability to distinguish plaque constituents. METHODS 50 histopathological images of carotid endarterectomy samples from 10 males and 2 females (age 54-74 years, average 65.9 years) were examined. We compared pre-operative CT [pre-contrast (CT-P), early post-contrast phase (CT-E), delayed post-contrast phase (CT-D)] of lipid-rich necrotic core (NC) and fibrous tissue (F) plaque components with pathological images. The ability of features to differentiate plaque components using several discrimination techniques were compared. RESULTS CT values of NC and F were 36 ± 13, 45 ± 11 (mean ± standard deviation, Hounsfield unit, HU), 41 ± 17, 69 ± 18, and 44 ± 16, 70 ± 13 in CT-P (p < 0.01), CT-E (p < 0.0001), and CT-D (p < 0.0001), respectively. The threshold, sensitivity, and accuracy for distinguishing NC from F were 44 HU, 74%, and 68%; 55 HU, 85%, and 85%; and 63 HU, 92%, and 84% in CTP, CT-E, and CT-D, respectively. CT-P had lower accuracy than CT-E and CT-D (both p < 0.05), but CT-E and CT-D were similar. CT-E and CT-D yielded 90 and 91% sensitivity and accuracy, respectively in linear discrimination analysis. CONCLUSION In both pre- and post-contrast CT, CT values were lower in NC than F. Although values overlapped, using two-phase post-contrast CTs improved discrimination ability. ADVANCES IN KNOWLEDGE Our findings may help to establish computer-aided diagnosis of vulnerable atherosclerotic plaques in future.
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Affiliation(s)
- Masahiro Higashi
- Department of Radiology, National Hospital Organization Osaka National Hospital, Osaka, Japan.,Department of Radiology, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Naoaki Yamada
- Department of Radiology, National Cerebral and Cardiovascular Center, Suita, Japan
| | | | - Chikao Yutani
- Department of Pathology, Amagasaki Central Hospital, Amagasaki, Japan.,Department of Pathology, Cardiovascular Center Osaka Gyoumeikan Hospital, Osaka, Japan
| | | | - Koji Iihara
- Department of Neurosurgery, Graduate School of Medical Science Kyushu University, Fukuoka, Japan
| | - Hiroaki Naito
- Department of Radiology, Nippon Life Hospital, Osaka, Japan
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5
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Does the Tube Voltage Affect the Characterization of Coronary Plaques on 100- and 120-kVp Computed Tomography Scans. J Comput Assist Tomogr 2019; 43:416-422. [PMID: 30762654 DOI: 10.1097/rct.0000000000000845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of this study was to compare the diagnostic performance of 100- and 120-kVp coronary computed tomography (CT) angiography (CCTA) scans for the identification of coronary plaque components. METHODS We included 116 patients with coronary plaques who underwent CCTA and integrated backscatter intravascular ultrasound studies. On 100-kVp scans, we observed 24 fibrous and 24 fatty/fibrofatty plaques; on 120-kVp scans, we noted 27 fibrous and 41 fatty/fibrofatty plaques. We compared the fibrous and the fatty/fibrofatty plaques, the CT number of the coronary lumen, and the radiation dose on scans obtained at 100 and 120 kVp. We also compared the area under the receiver operating characteristic (ROC) curve of the coronary plaques on 100- and 120-kVp scans with their ROC curves on integrated backscatter intravascular ultrasound images. RESULTS The mean CT numbers of fatty and fatty/fibrofatty plaques were 5.71 ± 36.5 and 76.6 ± 33.7 Hounsfield units (HU), respectively, on 100-kVp scans; on 120-kVp scans, they were 13.9 ± 29.4 and 54.5 ± 22.3 HU, respectively. The CT number of the coronary lumen was 323.1 ± 81.2 HU, and the radiation dose was 563.7 ± 81.2 mGy-cm on 100-kVp scans; these values were 279.3 ± 61.8 HU and 819.1 ± 115.1 mGy-cm on 120-kVp scans. The results of ROC curve analysis identified 30.5 HU as the optimal diagnostic cutoff value for 100-kVp scans (area under the curve = 0.93, 95% confidence interval = 0.87-0.99, sensitivity = 95.8%, specificity = 78.9%); for 120-kVp plaque images, the optimal cutoff was 37.4 HU (area under the curve = 0.87, 95% confidence interval = 0.79-0.96, sensitivity = 82.1%, specificity = 85.7%). CONCLUSIONS For the discrimination of coronary plaque components, the diagnostic performance of 100- and 120-kVp CCTA scans is comparable.
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Gabriel FS, Gonçalves LFG, Melo EVD, Sousa ACS, Pinto IMF, Santana SMM, Matos CJOD, Souto MJS, Conceição FMDS, Oliveira JLM. Atherosclerotic Plaque in Patients with Zero Calcium Score at Coronary Computed Tomography Angiography. Arq Bras Cardiol 2018; 110:420-427. [PMID: 29723329 PMCID: PMC5967134 DOI: 10.5935/abc.20180063] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 11/22/2017] [Indexed: 11/20/2022] Open
Abstract
Background In view of the high mortality for cardiovascular diseases, it has become
necessary to stratify the main risk factors and to choose the correct
diagnostic modality. Studies have demonstrated that a zero calcium score
(CS) is characteristic of a low risk for cardiovascular events. However, the
prevalence of individuals with coronary atherosclerotic plaques and zero CS
is conflicting in the specialized literature. Objective To evaluate the frequency of patients with coronary atherosclerotic plaques,
their degree of obstruction and associated factors in patients with zero CS
and indication for coronary computed tomography angiography (CCTA). Methods This is a cross-sectional, prospective study with 367 volunteers with zero CS
at CCTA in four diagnostic imaging centers in the period from 2011 to 2016.
A significance level of 5% and 95% confidence interval were adopted. Results The frequency of atherosclerotic plaque in the coronary arteries in 367
patients with zero CS was 9.3% (34 individuals). In this subgroup, mean age
was 52 ± 10 years, 18 (52.9%) were women and 16 (47%) had significant
coronary obstructions (> 50%), with involvement of two or more segments
in 4 (25%) patients. The frequency of non-obese individuals (90.6% vs 73.9%,
p = 0.037) and alcohol drinkers (55.9% vs 34.8%, p = 0.015) was
significantly higher in patients with atherosclerotic plaques, with an odds
ratio of 3.4 for each of this variable. Conclusions The frequency of atherosclerotic plaque with zero CS was relatively high,
indicating that the absence of calcification does not exclude the presence
of plaques, many of which obstructive, especially in non-obese subjects and
alcohol drinkers.
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Affiliation(s)
- Fabíola Santos Gabriel
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Clínica de Medicina Nuclear de Diabetes - CLIMEDI - Aracaju, SE - Brazil
| | - Luiz Flávio Galvão Gonçalves
- Centro de Pesquisas da Fundação São Lucas - Aracaju, SE - Brazil.,Clínica de Medicina Nuclear de Diabetes - CLIMEDI - Aracaju, SE - Brazil
| | - Enaldo Vieira de Melo
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil
| | - Antônio Carlos Sobral Sousa
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Departamento de Medicina - Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Centro de Ensino e Pesquisa e Laboratório de Ecocardiografia (ECOLAB) do Hospital e Fundação São Lucas - Aracaju, SE - Brazil
| | | | | | - Carlos José Oliveira de Matos
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Departamento de Medicina - Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil
| | - Maria Júlia Silveira Souto
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Departamento de Medicina - Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil
| | - Flávio Mateus do Sacramento Conceição
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Departamento de Medicina - Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil
| | - Joselina Luzia Menezes Oliveira
- Núcleo de Pós-Graduação em Medicina da Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Departamento de Medicina - Universidade Federal de Sergipe (UFS) - São Cristóvão, SE - Brazil.,Centro de Ensino e Pesquisa e Laboratório de Ecocardiografia (ECOLAB) do Hospital e Fundação São Lucas - Aracaju, SE - Brazil.,Instituto Dante Pazzanese de Cardiologia - São Paulo, SP - Brazil.,Centro de Ensino e Pesquisa da Fundação São Lucas - Aracaju, SE - Brazil
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7
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Gitsioudis G, Katus HA, Korosoglou G. Assessment of coronary artery disease using coronary computed tomography angiography and biochemical markers. World J Cardiol 2014; 6:663-670. [PMID: 25068026 PMCID: PMC4110614 DOI: 10.4330/wjc.v6.i7.663] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/16/2014] [Accepted: 05/29/2014] [Indexed: 02/06/2023] Open
Abstract
Chronic inflammatory mechanisms in the arterial wall lead to atherosclerosis, and include endothelial cell damage, inflammation, apoptosis, lipoprotein deposition, calcification and fibrosis. Cardiac computed tomography angiography (CCTA) has been shown to be a promising tool for non-invasive assessment of theses specific compositional and structural changes in coronary arteries. This review focuses on the technical background of CCTA-based quantitative plaque characterization. Furthermore, we discuss the available evidence for CCTA-based plaque characterization and the potential role of CCTA for risk stratification of patients with coronary artery disease.
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8
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Kasraie N, Mah P, Keener CR, Clarke GD. Characterization of atherosclerotic plaque: a contrast-detail study using multidetector and cone-beam computed tomography. J Appl Clin Med Phys 2014; 15:4308. [PMID: 24423833 PMCID: PMC5711236 DOI: 10.1120/jacmp.v15i1.4308] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 08/06/2013] [Accepted: 07/02/2013] [Indexed: 11/23/2022] Open
Abstract
A Hindmarsh-Rose model perceptibility phantom containing inserts with various in vitro atherosclerotic plaque compositions was constructed and imaged on a clinical 64 slice multidetector (MDCT) system using 80 and 120 kVp settings and two other cone-beam (CBCT) systems at 80 kVp. Perceptibility of the simulated lipid-fibrotic plaque solutions in the images was evaluated by six observers. The effective doses of the protocols employed were estimated using phantom CTDI-vol measurements placed at identical settings. The CBCT system allowed reduction in effective dose in comparison with the conventional MDCT system for imaging of the carotid plaque phantoms without degrading image quality. The CBCT dose was less than MDCT, with a mean dose of 1.14 ± 0.01 mSv and 1.11 ± 0.02 mSv for MDCT using two measuring techniques vs. 0.35 ± 0.01 mSv for CBCT. The image quality analysis showed no significant differences in the contrast-detail (C-D) curves of the best performing CBCT vs. clinical MDCT (p > 0.05) using a Mann-Whitney U test. Results indicate that low-tube-potential CBCT may produce comparable C-D resolution for phantom-based representations of soft plaque types with respect to MDCT systems. This study suggests that the utility of low kVp CT techniques for evaluating carotid vulnerable atherosclerotic plaque merits further study.
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Affiliation(s)
- Nima Kasraie
- The University of Texas Health Science Center at San Antonio.
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A meta analysis and hierarchical classification of HU-based atherosclerotic plaque characterization criteria. PLoS One 2013; 8:e73460. [PMID: 24019924 PMCID: PMC3760884 DOI: 10.1371/journal.pone.0073460] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 07/21/2013] [Indexed: 12/26/2022] Open
Abstract
Background Many computed tomography (CT) studies have reported that lipid-rich, presumably rupture-prone atherosclerotic plaques can be characterized according to their Hounsfield Unit (HU) value. However, the published HU-based characterization criteria vary considerably. The present study aims to systematically analyze these values and empirically derive a hierarchical classification of the HU-based criteria which can be referred in clinical situation. Material and Methods A systematic search in PubMed and Embase for publications with HU-criteria to characterize lipid-rich and fibrous atherosclerotic plaques resulted in 36 publications, published between 1998 and 2011. The HU-criteria were systematically analyzed based on the characteristics of the reporting study. Significant differences between HU-criteria were checked using Student’s t-test. Subsequently, a hierarchical classification of HU-criteria was developed based on the respective study characteristics. Results No correlation was found between HU-criteria and the reported lumen contrast-enhancement. Significant differences were found for HU-criteria when pooled according to the respective study characteristics: examination type, vessel type, CT-vendor, detector-rows, voltage-setting, and collimation-width. The hierarchical classification resulted in 21 and 22 CT attenuation value categories, for lipid-rich and fibrous plaque, respectively. More than 50% of the hierarchically classified HU-criteria were significantly different. Conclusion In conclusion, variations in the reported CT attenuation values for lipid-rich and fibrous plaque are so large that generalized values are unreliable for clinical use. The proposed hierarchical classification can be used to determine reference CT attenuation values of lipid-rich and fibrous plaques for the local setting.
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10
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Kwan AC, Cater G, Vargas J, Bluemke DA. Beyond Coronary Stenosis: Coronary Computed Tomographic Angiography for the Assessment of Atherosclerotic Plaque Burden. CURRENT CARDIOVASCULAR IMAGING REPORTS 2013; 6:89-101. [PMID: 23524381 PMCID: PMC3601491 DOI: 10.1007/s12410-012-9183-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Coronary computed tomographic angiography (CCTA) is emerging as a key non-invasive method for assessing cardiovascular risk by measurement of coronary stenosis and coronary artery calcium (CAC). New advancements in CCTA technology have led to the ability to directly identify and quantify the so-called "vulnerable" plaques that have features of positive remodeling and low density components. In addition, CCTA presents a new opportunity for noninvasive measurement of total coronary plaque burden that has not previously been available. The use of CCTA needs also to be balanced by its risks and, in particular, the associated radiation exposure. We review current uses of CCTA, CCTA's ability to measure plaque quantity and characteristics, and new developments in risk stratification and CCTA technology. CCTA represents a quickly developing field that will play a growing role in the non-invasive management of cardiovascular disease.
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Affiliation(s)
- Alan C Kwan
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
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11
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Kristanto W, van Ooijen PMA, Greuter MJW, Groen JM, Vliegenthart R, Oudkerk M. Non-calcified coronary atherosclerotic plaque visualization on CT: effects of contrast-enhancement and lipid-content fractions. Int J Cardiovasc Imaging 2013; 29:1137-48. [DOI: 10.1007/s10554-012-0176-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 12/21/2012] [Indexed: 11/25/2022]
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12
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Dettmer M, Glaser-Gallion N, Stolzmann P, Glaser-Gallion F, Fornaro J, Feuchtner G, Jochum W, Alkadhi H, Wildermuth S, Leschka S. Quantification of coronary artery stenosis with high-resolution CT in comparison with histopathology in an ex vivo study. Eur J Radiol 2012; 82:264-9. [PMID: 23116807 DOI: 10.1016/j.ejrad.2012.09.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/15/2012] [Accepted: 09/21/2012] [Indexed: 11/18/2022]
Abstract
PURPOSE To investigate the ex vivo performance of high-resolution computed tomography (CT) for quantitative assessment of percentage diameter stenosis in coronary arteries compared to histopathology. MATERIALS AND METHODS High-resolution CT was performed in 26 human heart specimens after the injection of iodinated contrast media into the coronary arteries. Coronary artery plaques were visually identified on CT images and the grade of stenosis for each plaque was measured with electronic calipers. All coronary plaques were characterized by histopathology according to the Stary classification, and the percentage of stenosis was measured. RESULTS CT depicted 84% (274/326) of all coronary plaques identified by histology. Missed plaques by CT were of Stary type I (n=31), type II (n=16), and type III (n=5). The stenosis degree significantly correlated between CT and histology (r=0.81, p<0.001). CT systematically overestimated the stenosis of calcified plaques (mean difference - 11.0 ± 9.5%, p<0.01) and systematically underestimated the stenosis of non-calcified plaques (mean difference -6.8 ± 10.4%, p<0.05), while there was no significant difference for mixed-type plaques (mean difference -0.4 ± 11.7%, p=0.85). There was a significant underestimation of stenosis degree as measured by CT for Stary II plaques (mean difference -14 ± 9%, p<0.01) and a significant overestimation for Stary VII plaques (mean difference 9 ± 10%, p<0.05), but there was no significant difference in stenosis degree between both modalities for other plaque types. CONCLUSIONS High-resolution CT reliably depicts advanced stage coronary plaques with an overall good correlation of stenosis degree compared to histology, however, the degree of stenosis is systematically overestimated in calcified and underestimated in non-calcified plaques.
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Affiliation(s)
- Matthias Dettmer
- Department of Pathology and Laboratory Medicine, University of Pittsburgh, S-417 BST 200 Lothrop Street, Pittsburgh, PA 15261, USA.
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Non-invasive assessment of atherosclerotic coronary lesion length using multidetector computed tomography angiography: comparison to quantitative coronary angiography. Int J Cardiovasc Imaging 2012; 28:2065-71. [PMID: 22271073 PMCID: PMC3485532 DOI: 10.1007/s10554-012-0015-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 01/04/2012] [Indexed: 12/03/2022]
Abstract
Multidetector computed tomography angiography (CTA) provides information on plaque extent and stenosis in the coronary wall. More accurate lesion assessment may be feasible with CTA as compared to invasive coronary angiography (ICA). Accordingly, lesion length assessment was compared between ICA and CTA in patients referred for CTA who underwent subsequent percutaneous coronary intervention (PCI). 89 patients clinically referred for CTA were subsequently referred for ICA and PCI. On CTA, lesion length was measured from the proximal to the distal shoulder of the plaque. Quantitative coronary angiography (QCA) was performed to analyze lesion length. Stent length was recorded for each lesion. In total, 119 lesions were retrospectively identified. Mean lesion length on CTA was 21.4 ± 8.4 mm and on QCA 12.6 ± 6.1 mm. Mean stent length deployed was 17.4 ± 5.3 mm. Lesion length on CTA was significantly longer than on QCA (difference 8.8 ± 6.7 mm, P < 0.001). Moreover, lesion length visualized on CTA was also significantly longer than mean stent length (CTA lesion length-stent length was 4.2 ± 8.7 mm, P < 0.001). Lesion length assessed by CTA is longer than that assessed by ICA. Possibly, CTA provides more accurate lesion length assessment than ICA and may facilitate improved guidance of percutaneous treatment of coronary lesions.
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14
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Jinzaki M, Okabe T, Endo A, Kawamura A, Koga S, Yamada M, Fukuda K, Kuribayashi S. Detection of Attenuated Plaque in Stable Angina With 64-Multidetector Computed Tomography. Circ J 2012; 76:1182-9. [DOI: 10.1253/circj.cj-11-1078] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Masahiro Jinzaki
- Department of Diagnostic Radiology, Keio University School of Medicine
| | - Teruo Okabe
- Cardiology Department, International University of Health and Welfare, Mita Hospital
| | - Ayaka Endo
- Cardiopulmonary Division, Keio University School of Medicine
| | - Akio Kawamura
- Cardiopulmonary Division, Keio University School of Medicine
| | - Seiko Koga
- Department of Diagnostic Radiology, Keio University School of Medicine
| | - Minoru Yamada
- Cardiovascular Imaging Laboratory in Research Park, Keio University School of Medicine
| | - Keiichi Fukuda
- Cardiopulmonary Division, Keio University School of Medicine
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15
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Higashi M. Noninvasive Assessment of Coronary Plaque Using Multidetector Row Computed Tomography - Does MDCT Accurately Estimate Plaque Vulnerability? (Con) -. Circ J 2011; 75:1522-8. [DOI: 10.1253/circj.cj-11-0313] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Masahiro Higashi
- Department of Radiology, National Cerebral and Cardiovascular Center
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16
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Utsunomiya D, Fukunaga T, Oda S, Awai K, Nakaura T, Urata J, Yamashita Y. Multidetector computed tomography evaluation of coronary plaque morphology in patients with stable angina. Heart Vessels 2010; 26:392-8. [DOI: 10.1007/s00380-010-0074-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Accepted: 07/16/2010] [Indexed: 10/18/2022]
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17
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Dalager MG, Bøttcher M, Andersen G, Thygesen J, Pedersen EM, Dejbjerg L, Gøtzsche O, Bøtker HE. Impact of luminal density on plaque classification by CT coronary angiography. Int J Cardiovasc Imaging 2010; 27:593-600. [PMID: 20820922 DOI: 10.1007/s10554-010-9695-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Accepted: 08/25/2010] [Indexed: 12/22/2022]
Abstract
UNLABELLED Non-invasive coronary CT angiography (CCTA) has the potential to characterize the composition of non-calcified coronary plaques. CT-density values characterized by Hounsfield Units (HU) may classify non-calcified plaques as fibrous or lipid-rich, but the luminal density caused by the applied contrast material influences HU in the plaques in vitro. The influence of luminal density on HU in non-calcified plaques in vivo is unknown. Hence the purpose of this study was to test whether plaque characterization by CCTA in vivo depends on luminal density. Two CCTA-scans using two different contrast protocols were obtained from 14 male patients with coronary artery disease. The two contrast protocols applied resulted in high and low luminal density. Eleven non- calcified and 13 calcified plaques were identified and confirmed by intravascular ultrasound. Luminal attenuation differed with the two contrast protocols; 326[284;367] vs. 118[103;134] HU (P < 0.00001). In non-calcified plaques mean HU-values was lower 48[28;69] vs. 11[-4;25] HU (P = 0.004) with the low density protocol. As a consequence three out of eleven non-calcified plaques (27%) were reclassified from fibrous (high) to lipid rich (low). For calcified plaques a less pronounced but still significant difference in HU-values was found with the low luminal density. 770[622;919] vs. 675[496;855] HU (P = 0.02). CONCLUSION Non-calcified plaques can be identified and classified by CCTA. However, the luminal density affects the absolute HU of both non-calcified and calcified plaques. Characterization and classification of non-calcified plaques by absolute CT values therefore requires standardization of contrast protocols.
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Affiliation(s)
- Maiken Glud Dalager
- Department of Cardiology, Aarhus University Hospital, Skejby, Brendstrupgårdsvej 100, 8200 Aarhus N, Denmark.
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18
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Computed tomographic attenuation value of coronary atherosclerotic plaques with different tube voltage: an ex vivo study. J Comput Assist Tomogr 2010; 34:58-63. [PMID: 20118723 DOI: 10.1097/rct.0b013e3181b66c41] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To compare the diagnostic performance of computed tomographic (CT) attenuation and CT attenuation ratio at different tube voltages for ex vivo plaque characterization. MATERIALS AND METHODS Human coronary arteries were obtained at the time of autopsy in 15 subjects. The coronary arteries were serially cut into 5-mm-long segments and scanned ex vivo using 4 sets of tube voltages and tube currents (80 kV, 660 mA; 100 kV, 500 mA; 120 kV, 400 mA; and 140 kV, 340 mA). The CT attenuation value at the center of each plaque was obtained, and the ratio of the CT attenuation value at the 80-kV setting divided by that at the 140-kV setting (Hounsfield ratio [HR], 80:140) was calculated. Separate receiver operating characteristic (ROC) analyses were used to assess the usefulness of the CT attenuation value and the 80:140 HR for the differential diagnosis of lipid-rich plaques from other types of plaques. RESULTS A total of 93 coronary plaques were detected macroscopically. Histological examination revealed 39 lipid-rich, 24 calcified, and 30 fibrotic plaques. At all the tube voltages, the CT attenuation values of the lipid-rich plaques were lower than those of the calcified plaques, whereas the CT attenuation values of the lipid-rich and fibrotic plaques overlapped. An ROC analysis showed that the area under the curve (AUC) for the differential diagnosis of lipid-rich plaques from fibrotic plaques was 0.813 at 80 kV, 0.772 at 100 kV, 0.682 at 120 kV, or 0.651 at 140 kV. Regarding the 80:140 HR, the AUC was 0.952 (0.029). The AUC was significantly larger at 80 and 100 kV and 80:140 HR compared with the AUC at 120 kV. CONCLUSIONS The diagnostic performance of CT analysis for ex vivo plaque characterization was superior at lower energy settings and using the dual-energy method.
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19
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Bruining N, Roelandt JRTC, Verheye S, Knaapen M, Onuma Y, Regar E, Cademartiri F, de Winter S, Van Langenhove G, Serruys PW, Hamers R, de Feyter PJ. Compositional volumetry of non-calcified coronary plaques by multislice computed tomography: an ex vivo feasibility study. EUROINTERVENTION 2010; 5:558-64. [PMID: 20142176 DOI: 10.4244/eijv5i5a91] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS Non-invasive quantitative compositional analysis of coronary plaque would be a major advantage to study coronary artery disease. This study explores the application to use the Hounsfield units (HU) distribution of coronary plaques imaged by multislice computed tomography-coronary angiography (MSCT-CA). METHODS AND RESULTS A dedicated computer-assisted method was developed to measure the HU distribution within a coronary plaque by MSCT-CA. To test the feasibility of the method, an ex vivo left anterior descending (LAD) coronary specimen, excised during autopsy, was imaged both by non-enhanced and enhanced MSCT-CA. Quantitative histology was used as a reference. To test the feasibility of the new volumetric analytic method, the MSCT-CA data were compared with volumetric histopathology. The coronary specimen, with a heterogeneously distributed plaque composition without large areas of calcification, was histologically sampled at five different locations, 5 mm apart, where at each location 15 sections were taken at 100 microm intervals, resulting in 75 individual histology sections. Tri-chrome Masson staining was used for histology quantification of three plaque/tissue components: smooth muscle cells (SMC), collagen and calcium. MSCT plaque composition was defined as "lower-HU" or "higher-HU" plaque and "calcium" based on the HU distribution. Comparison of the MSCT defined tissue components against histology showed a good relationship without significant differences. CONCLUSIONS This ex vivo study shows the feasibility of using the Hounsfield unit distribution to perform compositional coronary plaque volumetry by MSCT-CA. The results are encouraging.
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Affiliation(s)
- Nico Bruining
- Department of Cardiology, Erasmus MC, Thoraxcenter, Rotterdam, The Netherlands.
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20
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Papadakis M, Bodmann BG, Alexander SK, Vela D, Baid S, Gittens AA, Kouri DJ, Gertz SD, Jain S, Romero JR, Li X, Cherukuri P, Cody DD, Gladish GW, Aboshady I, Conyers JL, Casscells SW. Texture-based tissue characterization for high-resolution CT scans of coronary arteries. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/cnm.1189] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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21
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Ibanez B, Cimmino G, Bénézet-Mazuecos J, Santos-Gallego CG, Pinero A, Prat-González S, Speidl WS, Fuster V, García MJ, Sanz J, Badimon JJ. Quantification of serial changes in plaque burden using multi-detector computed tomography in experimental atherosclerosis. Atherosclerosis 2009; 202:185-91. [DOI: 10.1016/j.atherosclerosis.2008.03.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2008] [Revised: 02/28/2008] [Accepted: 03/20/2008] [Indexed: 10/22/2022]
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22
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Rodriguez Granillo GA. Non-invasive assessment of vulnerable plaque. EXPERT OPINION ON MEDICAL DIAGNOSTICS 2009; 3:53-66. [PMID: 23495963 DOI: 10.1517/17530050802607357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Sudden cardiac death or unheralded acute coronary syndromes are common initial manifestations of coronary atherosclerosis and most such events occur at sites of non-flow limiting coronary atherosclerosis. OBJECTIVE Non-invasive detection of high-risk plaques might provide a means to improve risk stratification in primary and secondary prevention settings. METHODS This review is focused on the potential of multidetector computed tomography coronary angiography (MDCT-CA) to provide the opportunity to identify different aspects of plaque vulnerability throughout the coronary tree in an accurate, fast, safe and non-invasive manner. CONCLUSION Coronary artery calcium scoring, on top of established risk stratification, could potentially be a cost-effective strategy for primary prevention. MDCT-CA allows a non-invasive evaluation of several features commonly seen in vulnerable plaques and has demonstrated an independent prognostic value on a patient basis. The value of the technique itself might result, potentially, in a better estimation of the relative risk of an invidual plaque to rupture.
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Affiliation(s)
- Gastón A Rodriguez Granillo
- Otamendi Hospital, Clínica La Sagrada Familia, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Department of Cardiovascular Imaging, Azcuenaga 870, Buenos Aires, Argentina +54 11 49648740 ; +54 11 49648740 ;
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23
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Coronary plaque imaging and characterization by CT. CURRENT CARDIOVASCULAR IMAGING REPORTS 2008. [DOI: 10.1007/s12410-008-0017-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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Pannu HK, Johnson PT, Fishman EK. 64 Slice multi-detector row cardiac CT. Emerg Radiol 2008; 16:1-10. [PMID: 18941811 DOI: 10.1007/s10140-008-0760-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Accepted: 08/04/2008] [Indexed: 10/21/2022]
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25
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Sarwar A, Rieber J, Mooyaart EAQ, Seneviratne SK, Houser SL, Bamberg F, Raffel OC, Gupta R, Kalra MK, Pien H, Lee H, Brady TJ, Hoffmann U. Calcified Plaque: Measurement of Area at Thin-Section Flat-Panel CT and 64-Section Multidetector CT and Comparison with Histopathologic Findings. Radiology 2008; 249:301-6. [PMID: 18710960 DOI: 10.1148/radiol.2483072003] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ammar Sarwar
- Cardiac MR PET CT Program, Massachusetts General Hospital, 165 Cambridge St, 4th Floor, Suite 400, Boston, MA 02114, USA
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26
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Abstract
The present case report describes a 37-year-old man who presented to the emergency room with symptoms of a myocardial infarction but no high-grade stenosis on conventional catheter angiography. Consecutive multidetector row computed tomography of the coronary arteries showed an intimal flap along a fibrous plaque formation in the left anterior descending artery. This finding was found to represent a plaque rupture, and the lesion was treated with an 18 mm stent. Multidetector row computed tomography helped to correctly position the stent by identifying the exact location of the rupture along the long plaque formation.
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27
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Identification and quantification of coronary atherosclerotic plaques: a comparison of 64-MDCT and intravascular ultrasound. AJR Am J Roentgenol 2008; 190:748-54. [PMID: 18287448 DOI: 10.2214/ajr.07.2763] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The purpose of this study was to compare the accuracy of 64-MDCT with that of intravascular ultrasound (IVUS) for the identification and quantitative analysis of coronary atherosclerotic plaques. MATERIALS AND METHODS Twenty-six patients (17 men, nine women; mean age, 56 years) with suspected coronary atherosclerotic disease were studied using contrast-enhanced 64-MDCT and IVUS. The coronary arteries were divided into 10-mm segments and vascular cross-sectional area (CSA), luminal CSA, and plaque burden were measured in each segment. Plaque analysis software was used to automatically detect both plaques and vessel walls on CT images. Two investigators who were blinded to IVUS results independently determined the presence, classification, and quantitative measurement of atherosclerotic plaques on the CT images, which were then compared with the IVUS images. RESULTS Of 40 coronary arteries, 247 of 263 segments were imaged and analyzed by both contrast-enhanced 64-MDCT and IVUS. Sixteen segments were ruled out because of poor CT image quality. Compared with IVUS, 64-MDCT enabled correct detection in 86 of 89 (96.6%) segments containing noncalcified plaques, 25 of 27 (92.6%) segments containing calcified plaques, and 118 of 131 (90.1%) segments without atherosclerotic plaques. Sensitivity, specificity, positive predictive value, and negative predictive value for the detection of plaques by 64-MDCT were 97.4%, 90.1%, 89.7%, and 97.5%, respectively. Plaque analysis software using predetermined Hounsfield unit ranges for different components of plaque was able to distinguish between fibrous, fibrous-soft, and calcified plaques to a significant degree, but was less able to distinguish between soft and fibrous, and between soft and fibrous-soft plaque. Cohen's kappa coefficient for the sole detection of atherosclerotic segments by observers was 0.91. The correlation coefficients to determine vascular CSA, luminal CSA, and plaque burden were r = 0.85, 0.82, and 0.77, respectively (p < 0.01). CONCLUSION Compared with IVUS, contrast-enhanced 64-MDCT has a good ability to identify and quantify coronary atherosclerotic plaques. However, the reliable differentiation of the composition of noncalcified plaques is still limited.
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28
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Shinohara M, Yamashita T, Tawa H, Takeda M, Sasaki N, Takaya T, Toh R, Takeuchi A, Ohigashi T, Shinohara K, Kawashima S, Yokoyama M, Hirata KI, Momose A. Atherosclerotic plaque imaging using phase-contrast X-ray computed tomography. Am J Physiol Heart Circ Physiol 2008; 294:H1094-100. [DOI: 10.1152/ajpheart.01149.2007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reliable, noninvasive imaging modalities to characterize plaque components are clinically desirable for detecting unstable coronary plaques, which cause acute coronary syndrome. Although recent clinical developments in computed tomography (CT) have enabled the visualization of luminal narrowing and calcified plaques in coronary arteries, the identification of noncalcified plaque components remains difficult. Phase-contrast X-ray CT imaging has great potentials to reveal the structures inside biological soft tissues, because its sensitivity to light elements is almost 1,000 times greater than that of absorption-contrast X-ray imaging. Moreover, a specific mass density of tissue can be estimated using phase-contrast X-ray CT. Ex vivo phase-contrast X-ray CT was performed using a synchrotron radiation source (SPring-8, Japan) to investigate atherosclerotic plaque components of apolipoprotein E-deficient mice. Samples were also histologically analyzed. Phase-contrast X-ray CT at a spatial resolution of 10–20 μm revealed atherosclerotic plaque components easily, and thin fibrous caps were detected. The specific mass densities of these plaque components were quantitatively estimated. The mass density of lipid area was significantly lower (1.011 ± 0.001766 g/ml) than that of smooth muscle area or collagen area (1.057 ± 0.001407 and 1.080 ± 0.001794 g/ml, respectively). Moreover, the three-dimensional assessment of plaques could provide their anatomical information. Phase-contrast X-ray CT can estimate the tissue mass density of atherosclerotic plaques and detect lipid-rich areas. It can be a promising noninvasive technique for the investigation of plaque components and detection of unstable coronary plaques.
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Characterization of atherosclerotic plaques in human coronary arteries with 16-slice multidetector row computed tomography by analysis of attenuation profiles. Acad Radiol 2008; 15:222-30. [PMID: 18206621 DOI: 10.1016/j.acra.2007.09.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 09/04/2007] [Accepted: 09/04/2007] [Indexed: 11/23/2022]
Abstract
RATIONALE AND OBJECTIVES We investigated if 16-slice multidetector row computed tomography (MDCT) allows correct classification of coronary plaques into calcified or noncalcified and further subclassification of noncalcified plaques into either lipid-rich with a necrotic core or fibrous. MATERIALS AND METHODS Coronary arteries of 30 isolated hearts were filled postmortem with a contrast medium and scanned with a 16-slice MDCT imager (Light Speed 16 pro, GEMS, Milwaukee, WI). Imaging parameters: collimation 16 x 0.625 mm, pitch 0.325, tube voltage 120 kV, tube current 250 mA, and gantry rotation time 500 milliseconds. The images were reformatted perpendicular to the axis of the coronary arteries (AW 4.2 software, GEMS) and analyzed by establishing attenuation profiles of the coronary cross sections (ImageJ 1.33n software, NIH, Bethesda, MD). Results were compared with the correlating histopathologic sections of the arteries. RESULTS Analysis of 195 CT cross-sections showed a sensitivity and specificity for the correct classification of calcified plaques of 100% and 97.3% and for noncalcified plaques of 80.8% and 95.1%, respectively. The attenuation of epicardial fat ranged from -119 Hounsfield units (HU) to 23 HU (median -71 HU), and from 93 HU to 625 HU (308 HU) for the contrast medium. Calcified plaques showed an attenuation between 333 HU and 1944 HU (1,089 HU), noncalcified plaques between 26 HU and 124 HU (52 HU). Further subclassification of noncalcified plaques showed attenuation values between 26 HU and 67 HU (median 44 HU) for lipid-rich plaques with a necrotic core and from 37 HU to 124 HU (median 67 HU) for fibrous plaques. CONCLUSIONS Coronary atherosclerotic plaques can be reliably identified and classified as either calcified or noncalcified by 16-slice MDCT in postmortem studies. Further differentiation of noncalcified plaques in either lipid-rich or fibrous is not reliably feasible because of substantial overlap of the attenuation.
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30
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Three-dimensional isotropic wavelets for post-acquisitional extraction of latent images of atherosclerotic plaque components from micro-computed tomography of human coronary arteries. Acad Radiol 2007; 14:1509-19. [PMID: 18035280 DOI: 10.1016/j.acra.2007.06.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 06/11/2007] [Accepted: 06/12/2007] [Indexed: 11/20/2022]
Abstract
RATIONALE AND OBJECTIVES The capability of wavelet transforms to separate signals into frequency bands is the basis for its use in image compression and storage, data management and transmission, and, recently, extraction of latent images of tissue components from noisy medical images. Analysis of temporal variations of radiofrequency backscatter of intravascular ultrasound with one-dimensional wavelets can detect lipid-laden plaque in coronary arteries with a sensitivity and specificity of >80%. In this study we evaluate the capability of a novel, 3-dimensional isotropic wavelet analysis to perform high resolution, non-directionally biased, statistically reliable, non-invasive discrimination between components of human coronary atherosclerotic plaques in micro-CT. MATERIALS AND METHODS Coronary artery segments (5-15 mm) were excised at necropsy from 18 individuals with advanced coronary atherosclerosis. Specimens were imaged using a GE Locus SP ex vivo micro-CT scanner and processed for histological correlation (833 sections). The isotropic wavelet constructs were applied to the entire volume of CT data of each arterial segment to distinguish tissue textures of varying scales and intensities. Voxels were classified and plaque characterization achieved by comparing the relative magnitudes of these wavelet constituents to that of several reference plaque tissue components. RESULTS Processing of micro-CT images via these isotropic wavelet algorithms permitted 3-D, color-coded, high resolution, digital discrimination between lumen, calcific deposits, lipid-rich deposits, and fibromuscular tissue providing detail not possible with conventional thresholding based on Hounsfield intensity units. Using the isotropic wavelets (with histology as the gold standard), lipid-rich pools approaching the size of the filter for the isotropic wavelet algorithm (0.25 mm [250 microns] in length) were identified with 81% sensitivity and 86% specificity. Calcific deposits, fibromuscular tissue, and lumen equal to or larger than the wavelet filter size were detected without error (100% sensitivity and specificity). CONCLUSION Isotropic wavelet analysis permits high resolution, multi-dimensional identification of coronary atherosclerotic plaque components in micro-CT with sensitivity and specificity similar to that achieved with data obtained invasively (from IVUS in vivo) using one-dimensional wavelets. Further studies are necessary to test the applicability of this technology to clinical, multi-detector scanners.
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Cademartiri F, La Grutta L, Palumbo A, Maffei E, Aldrovandi A, Malagò R, Alberghina F, Pugliese F, Runza G, Belgrano M, Midiri M, Cova MA, Krestin GP. Imaging techniques for the vulnerable coronary plaque. Radiol Med 2007; 112:637-59. [PMID: 17653628 DOI: 10.1007/s11547-007-0170-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2006] [Accepted: 10/02/2006] [Indexed: 02/07/2023]
Abstract
The goal of this article is to illustrate the main invasive and noninvasive diagnostic modalities to image the vulnerable coronary plaque, which is responsible for acute coronary syndrome. The main epidemiologic and histological issues are briefly discussed in order to provide an adequate background. Comprehensive coronary atherosclerosis imaging should involve visualization of the entire coronary artery tree and plaque characterization, including three-dimensional morphology, relationship with the lumen, composition, vascular remodelling and presence of inflammation. No single technique provides such a comprehensive description, and no available modality extensively identifies the vulnerable plaque. In particular, we describe multislice computed tomography, which at present seems to be the most promising noninvasive tool for an exhaustive image-based quantification of coronary atherosclerosis.
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Affiliation(s)
- F Cademartiri
- Dipartimento di Radiologia e Dipartimento Cuore, Imaging Cardiovascolare Non invasivo, Azienda Ospedaliera di Parma, Viale Rustici 2, I-43100 Parma, Italy.
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Iriart X, Brunot S, Coste P, Montaudon M, Dos-Santos P, Leroux L, Labeque JN, Jais C, Laurent F. Early characterization of atherosclerotic coronary plaques with multidetector computed tomography in patients with acute coronary syndrome: a comparative study with intravascular ultrasound. Eur Radiol 2007; 17:2581-8. [PMID: 17549491 DOI: 10.1007/s00330-007-0665-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 04/04/2007] [Accepted: 04/06/2007] [Indexed: 11/26/2022]
Abstract
We compared 16-slice computed tomography (CT) with intravascular ultrasound (IVUS) in their ability to identify the culprit lesion, and to assess plaque characterization and vascular remodelling in acute coronary syndrome (ACS). Twenty patients were prospectively studied. Coronary plaque identification and characterization were compared using 16-slice CT and 40-MHz catheter-based IVUS. Minimum lumen area (MLA), cross-sectional vessel area (CVA) and vessel remodelling were determined for each comparable lesion. One hundred and sixty-nine segments were compared and 84 plaques analysed. Sixteen-slice CT detected 95% of culprit lesions (19/20). No feature suggestive of plaque rupture was detected by 16-slice CT. Attenuation measurements within all lesions revealed different values for hypoechoic (38 +/- 33 HU), hyperechoic (94 +/- 44 HU), and calcified plaques (561 +/- 216 HU), (P < 0.001). Agreement between 16-slice CT and IVUS on measuring MLA and CVA was evaluated using Bland-Altman analysis. Pearson and intra-class coefficient (ICC) were 0.81 and 0.70 for MLA, and 0.81 and 0.36 for CVA, for 16-slice CT and IVUS, respectively. Agreement between both techniques for vessel positive remodelling was moderate (kappa = 0.54, P < 0.001). Sixteen-slice CT has shown moderate accuracy in quantifying and characterizing coronary plaques compared with IVUS. Spatial resolution of 16-slice CT remains a major limitation, however, to accurately assess the complex lesions involved in ACS.
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Affiliation(s)
- Xavier Iriart
- Université Bordeaux 2, Inserm U 441 Atherosclerose, F 33076, 146 rue Léo Saignat, 33000, Bordeaux, France
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Reimann AJ, Rinck D, Birinci-Aydogan A, Scheuering M, Burgstahler C, Schroeder S, Brodoefel H, Tsiflikas I, Herberts T, Flohr T, Claussen CD, Kopp AF, Heuschmid M. Dual-source computed tomography: advances of improved temporal resolution in coronary plaque imaging. Invest Radiol 2007; 42:196-203. [PMID: 17287650 DOI: 10.1097/01.rli.0000254409.79193.96] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The aim of this study was to quantify image quality gains of a moving coronary plaque phantom using dual-source computed tomography (DSCT) providing 83 milliseconds temporal resolution in direct comparison to 64 slice single-source multidetector CT (MDCT) with a temporal resolution of 165 milliseconds. MATERIALS AND METHODS Three cardiac vessel phantoms with fixed 50% stenosis and changing plaque configurations were mounted on a moving device simulating cardiac motion. Scans were performed at a simulated heart frequency of 60 to 120 bpm. Image quality assessment was performed in different anatomic orientations inside a thoracic phantom. RESULTS A significant improvement of image quality using the DSCT could be found (P=0.0002). Relevant factors influencing image quality aside from frequency (P=0.0002) are plaque composition (P<0.0001), as well as orientation (P<0.0001). CONCLUSION Scanning with 83 milliseconds temporal resolution improved image quality of coronary plaque at higher heart frequencies.
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Affiliation(s)
- Anja J Reimann
- Department of Diagnostic Radiology, Eberhard-Karls-University of Tuebingen, Tuebingen, Germany.
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Choe YH. Noninvasive Detection of Coronary Atherosclerotic Plaques and Assessment of Stenosis Degree at Multidetector CT Coronary Angiography. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2007. [DOI: 10.5124/jkma.2007.50.2.109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Yeon Hyeon Choe
- Department of Radiology, Sungkyunkwan University School of Medicine, Korea.
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Reiter M, Horvat R, Puchner S, Rinner W, Polterauer P, Lammer J, Minar E, Bucek RA. Plaque imaging of the internal carotid artery - correlation of B-flow imaging with histopathology. AJNR Am J Neuroradiol 2007; 28:122-6. [PMID: 17213437 PMCID: PMC8134122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
BACKGROUND AND PURPOSE The noninvasive identification of plaque types prone to cause symptomatic disease is of great interest to improve the effectiveness of surgical or interventional management. The purpose of the present prospective pilot study was to evaluate the association between the results of imaging-the novel sonography technique B-flow imaging (BFI), B-mode, and color Doppler imaging (CDI)-and histopathologic examination in the characterization of internal carotid artery (ICA) plaques. METHODS Twenty-eight consecutive patients with high-grade internal carotid artery stenosis scheduled for carotid endarterectomy were included. BFI, B-mode, and CDI images were used to classify the plaques applying the standardized scores of Beletsky et al and the American Heart Association (AHA), to calculate the gray-scale median (GSM) and to detect potential ulcerations; histopathologic examination results of explanted plaques served as the "gold standard." RESULTS Based on the classification of Beletsky et al, BFI and histopathologic examination results agreed in 21 (75%, kappa = 0.61, P < .001) patients, and the corresponding results for B-mode were 19 (68%, kappa = 0.52, P < .001) patients, respectively. Corresponding results for the AHA classification revealed inferior agreements for BFI (19 patients/68%, kappa = 0.38, P = .003) and B-mode (17 patients/61%, kappa = 0.25, P = .045). The median GSM for BFI and B-mode correlated significantly (r = 0.95, P < .001). The sensitivity of BFI for the detection of ulcerated plaques was 100% and the specificity was 95.8%; corresponding values for CDI were 100% and 92.7%, respectively. CONCLUSION BFI and the combination of B-mode and CDI exhibit comparable results in the assessment of ICA plaque components and plaque ulceration as well as in the determination of GSM levels.
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Affiliation(s)
- M Reiter
- University Clinic for Radiology, Department of Angiography and Interventional Radiology, Vienna General Hospital, Vienna, Austria.
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Ferencik M, Chan RC, Achenbach S, Lisauskas JB, Houser SL, Hoffmann U, Abbara S, Cury RC, Bouma BE, Tearney GJ, Brady TJ. Arterial wall imaging: evaluation with 16-section multidetector CT in blood vessel phantoms and ex vivo coronary arteries. Radiology 2006; 240:708-16. [PMID: 16857982 DOI: 10.1148/radiol.2403051204] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE To evaluate the diagnostic performance of 16-section multidetector computed tomography (CT) for assessment of plaques in phantoms and ex vivo coronary arteries, with intravascular ultrasonography (US) and optical coherence tomography (OCT) as reference standards. MATERIALS AND METHODS Research protocol was HIPAA compliant and approved by institutional review board, without informed consent required. Blood vessel and lesion composition phantoms and ex vivo coronary arteries were imaged with 16-section CT. Wall areas of phantoms and ex vivo coronary arteries were measured with multidetector CT and intravascular US. Sensitivity and specificity for lipid detection were determined in lesion composition phantoms. CT numbers of blood vessel wall were determined in ex vivo coronary arteries and compared with lesion classification results from OCT. Agreement in dimensional measurements was compared (paired t tests). CT numbers within blood vessel wall of CT cross sections classified as lipid rich, fibrous, and calcified at OCT were compared (Kruskal-Wallis tests). RESULTS Mean blood vessel wall areas measured with CT and US in phantoms were 9.2 mm(2) +/- 1.8 (standard deviation) and 10.4 mm(2) +/- 3.4 (bias, -1.3 mm(2) +/- 3.1; P < .05), respectively. Mean blood vessel wall areas measured in ex vivo coronary arteries with CT and US were 10.9 mm(2) +/- 4.1 and 9.1 mm(2) +/- 3.1 (bias, 1.8 mm(2) +/- 3.0; P < .001), respectively. Sensitivity and specificity of 93% and 92%, respectively, for identification of lipid-rich lesions were observed in lesion composition phantoms. Mean CT numbers in blood vessel wall of ex vivo coronary arteries identified at OCT as predominantly lipid rich, fibrous, and calcified were 29 HU +/- 43, 101 HU +/- 21, and 135 HU +/- 199, respectively (P < .001). CONCLUSION Determination of composition of individual plaques from attenuation values can be more challenging because of overlapping values for different tissue types.
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Affiliation(s)
- Maros Ferencik
- Department of Radiology, Wellman Laboratories of Photomedicine, Boston, MA 02114, USA
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Cordeiro MAS, Lima JAC. Atherosclerotic Plaque Characterization by Multidetector Row Computed Tomography Angiography. J Am Coll Cardiol 2006; 47:C40-7. [PMID: 16631509 DOI: 10.1016/j.jacc.2005.09.076] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 09/13/2005] [Accepted: 09/26/2005] [Indexed: 01/01/2023]
Abstract
Multidetector row computed tomography angiography (MDCTA) is seen as a potential alternative to current imaging methods for the assessment of vessel anatomy and atherosclerotic plaque composition/morphology in a great variety of arterial beds. Recent advances represented by the increase in gantry speed to <500 ms per rotation and in the number of detector rows from 4 to 64, in addition to the decrease in slice thickness to submillimetric levels, brought significant improvement in diagnostic accuracy by coronary MDCTA. In general, it has a good correlation with both intravascular ultrasound (IVUS) and histopathology for discrimination between soft, intermediate, and calcified plaques. Plaque area and volume tend to be underestimated by 12-detector row MDCTA and overestimated by 16-detector row MDCTA, but the number of patients studied so far is relatively small. However, it seems that 64-detector row MDCTA can measure plaque area and volume with greater accuracy. Plaque remodeling is overestimated in small vessels by 12-detector row MDCTA, whereas 16- and 64-detector row MDCTA show a good correlation with IVUS. Although still under development, the potential of MDCTA to characterize atherosclerotic plaque composition as well as to precisely determine plaque area, volume, and remodeling in the future is quite promising.
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Affiliation(s)
- Marco A S Cordeiro
- Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Gertz SD, Cherukuri P, Bodmann BG, Gladish G, Wilner WT, Conyers JL, Aboshady I, Madjid M, Vela D, Lukovenkov S, Papadakis M, Kouri D, Mazraeshahi RM, Frazier L, Zarrabi A, Elrod D, Willerson JT, Casscells SW. Usefulness of multidetector computed tomography for noninvasive evaluation of coronary arteries in asymptomatic patients. Am J Cardiol 2006; 97:287-93. [PMID: 16442381 DOI: 10.1016/j.amjcard.2005.08.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 08/12/2005] [Accepted: 08/12/2005] [Indexed: 11/20/2022]
Abstract
This editorial addresses the capabilities, limitations, and potential of multidetector computed tomography (MDCT) for the noninvasive evaluation of coronary arteries in asymptomatic patients. The quantification of coronary calcium with MDCT correlates highly with that obtained by electron-beam computed tomography, but to date, neither has the capability of assessing the distribution of various morphologic patterns of calcium and their relation to other "soft" plaque components. Although MDCT can assess the thickness of the atherosclerotic wall and can readily identify calcific deposits, further plaque characterization (e.g., lipid pools and fibrous tissue), a prerequisite for the identification of most vulnerable lesions, is not yet a workable reality, even with the 64-slice machines in their current configuration. The noninvasive identification by MDCT of plaque components subtending vulnerable lesions will require additional improvement in the primary instrumentation, the use of hybrid constructs (e.g., with positron emission tomography and magnetic resonance imaging), the development of novel methods of post-acquisitional analysis to extract latent images of plaque components (e.g., signal analysis based on 3-dimensional wavelets), or the adaptation of molecular imaging techniques at the cell and gene levels to computed tomography. Such unique approaches may soon contribute a long list of additional parameters that could be evaluated on a noninvasive basis as predictors of acute coronary syndromes and overall patient vulnerability.
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Shin DI, Won YD, Chang K, Seung W, Kim PJ, Park YJ, Jung HO, Jeon HK, Baek SH, Chung WS, Kim KT, Kim YJ, Seung KB. Multidetector Row Computed Tomography Noninvasively Assesses Coronary Reperfusion After Thrombolytic Therapy in Patients With ST Elevation Myocardial Infarction. Circ J 2006; 70:1590-7. [PMID: 17127805 DOI: 10.1253/circj.70.1590] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND The study objective was to assess the efficacy of 16-slice multidetector row computed tomography (MDCT) in estimating residual stenosis and successful reperfusion after thrombolysis in patients with ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS A total of 31 patients with STEMI underwent MDCT scanning within 6 h (mean 4.6+/-1.1) after thrombolysis and the results for detection of significant residual stenosis and distal flow of the infarct-related artery were compared with those from conventional coronary angiography (CCAG) performed within 24 h (mean 12.1+/-5.6) after the MDCT scan. Successful reperfusion was defined as Thrombolysis In Myocardial Infarction flow 2 or 3 on CCAG and full contrast enhancement of the distal artery landmarks on MDCT. A final analysis was performed using 24 patients (312 segments). MDCT had a positive predictive value of 73.3% and a negative predictive value of 95.1% for detecting significant residual stenosis. It accurately estimated 17 of 18 patients (94.4%) with successful reperfusion and 5 of 6 (83.3%) with failed reperfusion on the basis of comparison with CCAG. CONCLUSIONS MDCT demonstrated high accuracy not only for the detecting residual stenosis, but also for assessing successful reperfusion after thrombolytic therapy in patients with STEMI.
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Affiliation(s)
- Dong Il Shin
- Department of Internal Medicine, The catholic University of Korea, Seoul, South Korea
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Abstract
The concept of vulnerable plaque is well established with increasing evidence from clinical and basic research. The paradigm has shifted from focusing exclusively on the hemodynamic effects of plaque (ie, resulting lumenal stenosis alone as a predictor of stroke risk) to assessment of the structure and composition of plaque (eg, denuded endothelium with inflammatory elements as a nidus for platelet-fibrin clumping). It is increasingly evident that methods to detect and characterize vulnerable plaque must be developed and optimized. Although MR imaging, CT, and ultrasound provide data regarding single lesions, future investigations relying heavily on nuclear medicine techniques may offer functional assessment of the entire cardiovascular system.
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Affiliation(s)
- John W Chen
- Division of Neuroradiology, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.
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