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Deng J, Wang Y, Qi T, Li Z, Zheng H, Wu Y, Lu L, Li D, Han D, Chen W. Myocardial extracellular volume fraction with spectral detector computed tomography for risk stratification in non-ischemic heart failure. LA RADIOLOGIA MEDICA 2025:10.1007/s11547-025-02002-1. [PMID: 40304953 DOI: 10.1007/s11547-025-02002-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 03/14/2025] [Indexed: 05/02/2025]
Abstract
PURPOSE To validate the feasibility of using late iodine enhancement (LIE)-derived ECV on iodine density images using spectral detector computed tomography (SDCT; CT-ECV) and to assess the potential of CT-ECV for risk stratification among patients with non-ischemic heart failure (NIHF). MATERIALS AND METHODS Forty-five subjects who underwent cardiac SDCT and CMR were included in the validation group to calculate and compare CT-ECV with CMR-ECV to validate CT-ECV feasibility. Another 117 subjects (82 patients with NIHF, 35 controls) who underwent SDCT were included in the experimental group to explore the potential of CT-ECV for risk stratification. ECV was measured via iodine density images and CMR T1 mapping in accordance with American Heart Association 16-segment models. RESULTS In the validation group, there was no significant difference between CT-ECV and CMR-ECV (P = 0.293), with an insignificant bias. In the experimental group, CT-ECV in patients with NIHF was significantly higher than in controls (P < 0.05). In 82 patients with NIHF, CT-ECV in HFrEF ( HF with reduced ejection fraction: LVEF ≤ 40%) patients was statistically higher than that of HFmEF (HF with mildly reduced ejection fraction: LVEF 41-49%) and HFpEF (HF with preserved ejection fraction: LVEF ≥ 50%) patients (P < 0.05) and a significant difference among patients with NIHF with varied New York Heart Association classes (all P < 0.05); In addition, Kaplan-Meier survival curves and Log-rank test demonstrated that NIHF patients with CT-ECV ≥ 31.29% had higher probability of MACE than NIHF patients with CT-ECV < 31.29% (P < 0.001). CONCLUSION LIE-derived CT-ECV on iodine density images using SDCT is a promising practical alternative to CMR-ECV, with the potential to assist with risk stratification among patients with NIHF.
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Affiliation(s)
- Jie Deng
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
- Department of Nuclear Medicine, Sun Yat-Sen Memorial Hospital, No. 107, The West of Yanjiang Road, Guangzhou, 510120, China
| | - Yu Wang
- Department of Ultrasound, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Tianfu Qi
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Zhiming Li
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Hongen Zheng
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Yan Wu
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Lin Lu
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Deyan Li
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Dan Han
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China
| | - Wei Chen
- Department of Radiology, First Affiliated Hospital of Kunming Medical University, 295 Xichang Road, Kunming, 650032, China.
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Muscogiuri G, Palumbo P, Kitagawa K, Nakamura S, Senatieri A, De Cecco CN, Gershon G, Chierchia G, Usai J, Sferratore D, D'Angelo T, Guglielmo M, Dell'Aversana S, Jankovic S, Salgado R, Saba L, Cau R, Marra P, Di Cesare E, Sironi S. State of the art of CT myocardial perfusion. LA RADIOLOGIA MEDICA 2025; 130:438-452. [PMID: 39704963 DOI: 10.1007/s11547-024-01942-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2024] [Accepted: 12/11/2024] [Indexed: 12/21/2024]
Abstract
Coronary computed tomography angiography (CCTA) is a powerful tool to rule out coronary artery disease (CAD). In the last decade, myocardial perfusion CT (CTP) technique has been developed for the evaluation of myocardial ischemia, thereby increasing positive predictive value for diagnosis of obstructive CAD. A diagnostic strategy combining CCTA and perfusion acquisitions provides both anatomical coronary evaluation and functional evaluation of the stenosis, increasing the specificity and the positive predictive value of cardiac CT. This could improve risk stratification and guide revascularization procedures, reducing unnecessary diagnostic procedures in invasive coronary angiography. Two different acquisitions protocol have been developed for CTP. Static CTP allows a qualitative or semiquantitative evaluation of myocardial perfusion using a single scan during the first pass of iodinated contrast material in the myocardium. Dynamic CTP is capable of a quantitative evaluation of perfusion through multiple acquisitions, providing direct measure of the myocardial blood flow. For both, CTP acquisition hyperemia is reached using stressor agents such as adenosine or regadenoson. CTP in addition to CCTA acquisition shows good diagnostic accuracy compared to invasive fractional flow reserve (FFR). Furthermore, the evaluation of late iodine enhancement (LIE) could be performed allowing the detection of myocardial infarction.
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Affiliation(s)
- Giuseppe Muscogiuri
- Department of Radiology, ASST Papa Giovanni XXIII Hospital, Piazza OMS, 1, 24127, Bergamo, Italy.
- School of Medicine, University of Milano-Bicocca, Milan, Italy.
| | - Pierpaolo Palumbo
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - Kakuya Kitagawa
- Regional Co-Creation Deployment Center, Mie University Mie Regional Plan Co-Creation Organization, Mie, Japan
- Department of Advanced Diagnostic Imaging, Mie University Graduate School of Medicine, Mie, Japan
| | - Satoshi Nakamura
- Department of Advanced Diagnostic Imaging, Mie University Graduate School of Medicine, Mie, Japan
| | | | - Carlo Nicola De Cecco
- Division of Cardiothoracic Imaging, Department of Radiology and Imaging Sciences, Emory University, Altanta, GA, USA
- Translational Laboratory for Cardiothoracic Imaging and Artificial Intelligence, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Gabrielle Gershon
- Translational Laboratory for Cardiothoracic Imaging and Artificial Intelligence, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | | | - Jessica Usai
- School of Medicine, University of Milano-Bicocca, Milan, Italy
| | | | - Tommaso D'Angelo
- Diagnostic and Interventional Radiology Unit, Department of Dental and Morphological and Functional Imaging, University Hospital Messina, Messina, Italy
| | - Marco Guglielmo
- Department of Cardiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Sonja Jankovic
- Center for Radiology, University Clinical Center Nis, Nis, Republic of Serbia
| | - Rodrigo Salgado
- Department of Radiology, Antwerp University Hospital & Holy Heart Lier, Antwerp, Belgium
| | - Luca Saba
- Department of Radiology, Azienda Ospedaliero Universitaria, Monserrato, Cagliari, Italy
| | - Riccardo Cau
- Department of Radiology, Azienda Ospedaliero Universitaria, Monserrato, Cagliari, Italy
| | - Paolo Marra
- Department of Radiology, ASST Papa Giovanni XXIII Hospital, Piazza OMS, 1, 24127, Bergamo, Italy
- School of Medicine, University of Milano-Bicocca, Milan, Italy
| | - Ernesto Di Cesare
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Sandro Sironi
- Department of Radiology, ASST Papa Giovanni XXIII Hospital, Piazza OMS, 1, 24127, Bergamo, Italy
- School of Medicine, University of Milano-Bicocca, Milan, Italy
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Yan C, Ma J, Tian D, Yan T, Zhang C, Zhang F, Zhao Y, Fu S, Zhang Q, Xia M, Li Y, Sun Y. Evaluation of pulmonary artery pressure, blood indices, and myocardial microcirculation in rats returning from high altitude to moderate altitude. Eur Radiol Exp 2024; 8:131. [PMID: 39565546 PMCID: PMC11579275 DOI: 10.1186/s41747-024-00514-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 09/09/2024] [Indexed: 11/21/2024] Open
Abstract
BACKGROUND To investigate changes in pulmonary artery pressure (PAP), blood indices, and myocardial microcirculation in rats returning from high altitude (HA) to moderate altitude (MA). METHODS Forty 4-week-old male Sprague-Dawley rats were randomly divided into four groups with ten rats in each group. One group was transported to the MA area (MA-group), and the other three groups were transported to HA (HA-group-A, HA-group-B, and HA-group-C). After 28 weeks of age, the rats from the HA area were transported to the MA area for 0 days, 10 days, and 20 days, respectively. PAP, routine blood tests, and computed tomography myocardial perfusion indices were measured. RESULTS Compared with the MA-group, the body weight of HA-groups decreased (p < 0.05), and PAP in HA-group-A and HA-group-B increased (p < 0.05). In the HA groups, PAP initially increased and then decreased. Compared with the MA-group, red blood cells (RBC), hemoglobin (HGB), and hematocrit (HCT) of rats in HA-group-A increased (p < 0.05). Compared with the HA-group-A, RBC, HGB, and HCT of HA-group-B gradually decreased (p < 0.05) while MCV decreased (p < 0.05), and PLT of HA-group-C increased (p < 0.05). Compared with the MA group, blood flow (BF) and blood volume (BV) of the HA-group-A decreased (p < 0.05). Compared with the HA-group-A, TTP increased first and then decreased (p < 0.05), and BF and BV increased gradually (p < 0.05). Pathological results showed that myocardial fiber arrangement was disordered, and cell space widened in the HA group. CONCLUSION PAP, blood parameters, and myocardial microcirculation in rats returning from high to MA exhibited significant changes. RELEVANCE STATEMENT This study provides an experimental basis for understanding the physiological and pathological mechanisms during the process of deacclimatization to HA and offers new insights for the prevention and treatment of deacclimatization to HA syndrome. KEY POINTS Forty rats were raised in a real plateau environment. Myocardial microcirculation was detected by CT myocardial perfusion imaging. The PAP of the unacclimated rats increased first and then decreased. The myocardial microcirculation of the deacclimated rats showed hyperperfusion changes.
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Affiliation(s)
- Chunlong Yan
- Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing, China
- Department of Radiology, Jining No.1 People's Hospital, Jining, China
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
| | - Jinfeng Ma
- Department of Hematology, Jining No.1 People's Hospital, Jining, China
| | - Dengfeng Tian
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
| | | | - Chenhong Zhang
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
| | - Fengjuan Zhang
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
- Graduate School of Qinghai University, Xining, China
| | - Yuchun Zhao
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
- Graduate School of Qinghai University, Xining, China
| | - Shihan Fu
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
- Graduate School of Qinghai University, Xining, China
| | - Qiang Zhang
- Department of Neurosurgery, Qinghai Provincial People's Hospital, Xining, China
| | - Mengxue Xia
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
- Graduate School of Qinghai University, Xining, China
| | - Yue Li
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China
- Graduate School of Qinghai University, Xining, China
| | - Yanqiu Sun
- Department of Radiology, Qinghai Provincial People's Hospital, Xining, China.
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Englert F, Bahlke F, Erhard N, Krafft H, Popa MA, Risse E, Lennerz C, Lengauer S, Telishevska M, Reents T, Kottmaier M, Kolb C, Hessling G, Deisenhofer I, Bourier F. VT ablation based on CT imaging substrate visualization: results from a large cohort of ischemic and non-ischemic cardiomyopathy patients. Clin Res Cardiol 2024; 113:1478-1484. [PMID: 38112744 PMCID: PMC11420303 DOI: 10.1007/s00392-023-02321-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 10/09/2023] [Indexed: 12/21/2023]
Abstract
INTRODUCTION The eradication of ventricular tachycardia (VT) isthmus sites constitutes the minimal procedural endpoint for VT ablation procedures. Contemporary high-resolution computed tomography (CT) imaging, in combination with computer-assisted analysis and segmentation of CT data, facilitates targeted elimination of VT isthmi. In this context, inHEART offers digitally rendered three-dimensional (3D) cardiac models which allow preoperative planning for VT ablations in ischemic and non-ischemic cardiomyopathies. To date, almost no data have been collected to compare the outcomes of VT ablations utilizing inHEART with those of traditional ablation approaches. METHODS The presented data are derived from a retrospective analysis of n = 108 patients, with one cohort undergoing VT ablation aided by late-enhancement CT and subsequent analysis and segmentation by inHEART, while the other cohort received ablation through conventional methods like substrate mapping and activation mapping. The ablations were executed utilizing a 3D mapping system (Carto3), with the mapping generated via the CARTO® PENTARAY™ NAV catheter and subsequently merged with the inHEART model, if available. RESULTS Results showed more successful outcome of ablations for the inHEART group with lower VT recurrence (27% vs. 42%, p < 0.06). Subsequent analyses revealed that patients with ischemic cardiomyopathies appeared to derive a significant benefit from inHEART-assisted VT ablation procedures, with a higher rate of successful ablation (p = 0.05). CONCLUSION Our findings indicate that inHEART-guided ablation is associated with reduced VT recurrence compared to conventional procedures. This suggests that employing advanced imaging and computational modeling in VT ablation may be valuable for VT recurrences.
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Affiliation(s)
- F Englert
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - F Bahlke
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - N Erhard
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - H Krafft
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - M-A Popa
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - E Risse
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - C Lennerz
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - S Lengauer
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - M Telishevska
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - T Reents
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - M Kottmaier
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - C Kolb
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - G Hessling
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - I Deisenhofer
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany
| | - F Bourier
- Department of Electrophysiology, German Heart Center Munich, Technical University of Munich (TUM), Lazarettstr. 36, 80636, Munich, Germany.
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5
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Scala A, Marchini F, Meossi S, Zanarelli L, Sanguettoli F, Frascaro F, Bianchi N, Cocco M, Erriquez A, Tonet E, Campo G, Pavasini R. Future of invasive and non-invasive hemodynamic assessment for coronary artery disease management. Minerva Cardiol Angiol 2024; 72:385-404. [PMID: 38934267 DOI: 10.23736/s2724-5683.23.06461-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Coronary artery disease represents a global health challenge. Accurate diagnosis and evaluation of hemodynamic parameters are crucial for optimizing patient management and outcomes. Nowadays a wide range of both non-invasive and invasive methods are available to assess the hemodynamic impact of both epicardial coronary stenosis and vasomotor disorders. In fact, over the years, important developments have reshaped the nature of both invasive and non-invasive diagnostic techniques, and the future holds promises for further innovation and integration. Non-invasive techniques have progressively evolved and currently a broad spectrum of methods are available, from cardiac magnetic resonance imaging with pharmacological stress and coronary computed tomography (CT) to the newer application of FFR-CT and perfusion CT. Invasive methods, on the contrary, have developed to a full-physiology approach, able not only to identify functionally significant lesions but also to evaluate microcirculation and vasospastic disease. The aim of this review is to summarize the current state-of-the-art of invasive and non-invasive hemodynamic assessment for CAD management.
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Affiliation(s)
- Antonella Scala
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Federico Marchini
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Sofia Meossi
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Luca Zanarelli
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | | | - Federica Frascaro
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Nicola Bianchi
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Marta Cocco
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Andrea Erriquez
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Elisabetta Tonet
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
| | - Gianluca Campo
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy -
| | - Rita Pavasini
- Cardiology Unit, Azienda Ospedaliero Universitaria di Ferrara, Ferrara, Italy
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Tually PJ, Currie G, Lenzo NP, Hendrie DV, Meadows JW, Janssen JHA. Potential utility of B-Type natriuretic peptides in secondary prevention following percutaneous coronary intervention in remote communities of Western Australia. Biomarkers 2023:1-8. [PMID: 37128799 DOI: 10.1080/1354750x.2023.2209705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Introduction: A third of all acute coronary events that present in the Australian population occur in patients with established coronary heart disease. This study assessed the prognostic value of combined B-type natriuretic peptides (BNP) measurement and quantitative myocardial perfusion scan (MPS) data for cardiac events (CE).Material and methods: This retrospective cohort study involved 133 patients from rural Western Australia. The cut-off for normality was 6.0 for qualitative summed difference scores (SDS) of MPS and 400 pg/mL for BNP.Results: Patients with no CE had a mean SDS and BNP (1.52 with a 95% CI of 0.34 to 2.69), (175.9 with a 95% CI of 112.7-239.1) that was lower than patients with CE (6.54 with 95% CI 4.18-9.89) (P = 0.0003), (669.1 with 95% CI 543.9-794.3) (P < 0.0001). The sensitivity and specificity of combined testing for predicting CE respectively were 79.6% and 86.3% for SDS, 84.6% and 94.1% for BNP, and 100% and 92.7% for SDS and BNP combined.Discussion and conclusion: Elevated BNP is marginally superior to MPS in predicting CEs in patients who have previously undergone percutaneous coronary intervention (PCI); however, MPS can identify the region of myocardium most at risk. Routine BNP monitoring in this subgroup may serve as secondary prevention by identifying subclinical disease.
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Affiliation(s)
- Peter J Tually
- Department of Nuclear Medicine, Telemed Health, 20 Maritana St, Kalgoorlie, 6430, WA Australia
- Centre for Population Health Research, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Geoff Currie
- School of Dentistry and Health Sciences, Charles Sturt University, Wagga Wagga, 2678 New South Wales, Australia
| | - Nat P Lenzo
- Department of Nuclear Medicine, Telemed Health, 20 Maritana St, Kalgoorlie, 6430, WA Australia
- School of Medicine, University of Western Australia, Crawley, Western Australia, Australia
| | - Delia V Hendrie
- Centre for Population Health Research, Curtin University, GPO Box U1987, Perth, WA, 6845, Australia
| | - Jack W Meadows
- Department of Nuclear Medicine, Telemed Health, 20 Maritana St, Kalgoorlie, 6430, WA Australia
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Lara-Hernandez A, Rienmuller T, Juarez I, Perez M, Reyna F, Baumgartner D, Makarenko VN, Bockeria OL, Maksudov M, Rienmuller R, Baumgartner C. Deep Learning-Based Image Registration in Dynamic Myocardial Perfusion CT Imaging. IEEE TRANSACTIONS ON MEDICAL IMAGING 2023; 42:684-696. [PMID: 36227828 DOI: 10.1109/tmi.2022.3214380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Registration of dynamic CT image sequences is a crucial preprocessing step for clinical evaluation of multiple physiological determinants in the heart such as global and regional myocardial perfusion. In this work, we present a deformable deep learning-based image registration method for quantitative myocardial perfusion CT examinations, which in contrast to previous approaches, takes into account some unique challenges such as low image quality with less accurate anatomical landmarks, dynamic changes of contrast agent concentration in the heart chambers and tissue, and misalignment caused by cardiac stress, respiration, and patient motion. The introduced method uses a recursive cascade network with a ventricle segmentation module, and a novel loss function that accounts for local contrast changes over time. It was trained and validated on a dataset of n = 118 patients with known or suspected coronary artery disease and/or aortic valve insufficiency. Our results demonstrate that the proposed method is capable of registering dynamic cardiac perfusion sequences by reducing local tissue displacements of the left ventricle (LV), whereas contrast changes do not affect the registration and image quality, in particular the absolute CT (HU) values of the entire CT sequence. In addition, the deep learning-based approach presented reveals a short processing time of a few seconds compared to conventional image registration methods, demonstrating its application potential for quantitative CT myocardial perfusion measurements in daily clinical routine.
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Farhadi F, Rajagopal JR, Veziroglu EM, Abdollahi H, Shiri I, Nikpanah M, Morris MA, Zaidi H, Rahmim A, Saboury B. Multi-Scale Temporal Imaging: From Micro- and Meso- to Macro-scale-time Nuclear Medicine. PET Clin 2023; 18:135-148. [DOI: 10.1016/j.cpet.2022.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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Li S, Zeng D, Bian Z, Ma J. Noise modelling of perfusion CT images for robust hemodynamic parameter estimations. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac6d9b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 05/06/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. The radiation dose of cerebral perfusion computed tomography (CPCT) imaging can be reduced by lowering the milliampere-second or kilovoltage peak. However, dose reduction can decrease image quality due to excessive x-ray quanta fluctuation and reduced detector signal relative to system electronic noise, thereby influencing the accuracy of hemodynamic parameters for patients with acute stroke. Existing low-dose CPCT denoising methods, which mainly focus on specific temporal and spatial prior knowledge in low-dose CPCT images, not take the noise distribution characteristics of low-dose CPCT images into consideration. In practice, the noise of low-dose CPCT images can be much more complicated. This study first investigates the noise properties in low-dose CPCT images and proposes a perfusion deconvolution model based on the noise properties. Approach. To characterize the noise distribution in CPCT images properly, we analyze noise properties in low-dose CPCT images and find that the intra-frame noise distribution may vary in the different areas and the inter-frame noise also may vary in low-dose CPCT images. Thus, we attempt the first-ever effort to model CPCT noise with a non-independent and identical distribution (i.i.d.) mixture-of-Gaussians (MoG) model for noise assumption. Furthermore, we integrate the noise modeling strategy into a perfusion deconvolution model and present a novel perfusion deconvolution method by using self-relative structural similarity information and MoG model (named as SR-MoG) to estimate the hemodynamic parameters accurately. In the presented SR-MoG method, the self-relative structural similarity information is obtained from preprocessed low-dose CPCT images. Main results. The results show that the presented SR-MoG method can achieve promising gains over the existing deconvolution approaches. In particular, the average root-mean-square error (RMSE) of cerebral blood flow (CBF), cerebral blood volume, and mean transit time was improved by 40.3%, 69.1%, and 40.8% in the digital phantom study, and the average RMSE of CBF can be improved by 81.0% in the clinical data study, compared with tensor total variation regularization deconvolution method. Significance. The presented SR-MoG method can estimate high-accuracy hemodynamic parameters andachieve promising gains over the existing deconvolution approaches.
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10
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Freitas SA, Nienow D, da Costa CA, Ramos GDO. Functional Coronary Artery Assessment: a Systematic Literature Review. Wien Klin Wochenschr 2021; 134:302-318. [PMID: 34870740 DOI: 10.1007/s00508-021-01970-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 10/11/2021] [Indexed: 11/28/2022]
Abstract
Cardiovascular diseases represent the number one cause of death in the world, including the most common disorders in the heart's health, namely coronary artery disease (CAD). CAD is mainly caused by fat accumulated in the arteries' internal walls, creating an atherosclerotic plaque that impacts the blood flow functional behavior. Anatomical plaque characteristics are essential but not sufficient for a complete functional assessment of CAD. In fact, plaque analysis and visual inspection alone have proven insufficient to determine the lesion severity and hemodynamic repercussion. Furthermore, the fractional flow reserve (FFR) exam, which is considered the gold standard for stenosis functional impair determination, is invasive and contains several limitations. Such a panorama evidences the need for new techniques applied to image exams to improve CAD functional assessment. In this article, we perform a systematic literature review on emerging methods determining CAD significance, thus delivering a unique base for comparing these methods, qualitatively and quantitatively. Our goal is to guide further studies with evidence from the most promising methods, highlighting the benefits from both areas. We summarize benchmarks, metrics for evaluation, and challenges already faced, thus shedding light on the requirements for a valid, meaningful, and accepted technique for functional assessment evaluation. We create a base of comparison based on quantitative and qualitative indicators and highlight the most relevant geometrical metrics that correlate with lesion significance. Finally, we point out future benchmarks based on recent literature.
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Affiliation(s)
- Samuel A Freitas
- Software Innovation Laboratory, Graduate Program in Applied Computing, Universidade do Vale do Rio dos Sinos, São Leopoldo, Brazil
| | - Débora Nienow
- Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Cristiano A da Costa
- Software Innovation Laboratory, Graduate Program in Applied Computing, Universidade do Vale do Rio dos Sinos, São Leopoldo, Brazil
| | - Gabriel de O Ramos
- Software Innovation Laboratory, Graduate Program in Applied Computing, Universidade do Vale do Rio dos Sinos, São Leopoldo, Brazil.
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11
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Tarkowski P, Czekajska-Chehab E. Dual-Energy Heart CT: Beyond Better Angiography-Review. J Clin Med 2021; 10:jcm10215193. [PMID: 34768713 PMCID: PMC8584316 DOI: 10.3390/jcm10215193] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 12/30/2022] Open
Abstract
Heart CT has undergone substantial development from the use of calcium scores performed on electron beam CT to modern 256+-row CT scanners. The latest big step in its evolution was the invention of dual-energy scanners with much greater capabilities than just performing better ECG-gated angio-CT. In this review, we present the unique features of dual-energy CT in heart diagnostics.
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12
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Liu J, Jin S, Li Q, Zhang K, Yu J, Mo Y, Bian Z, Gao Y, Zhang H. Motion compensation combining with local low rank regularization for low dose dynamic CT myocardial perfusion reconstruction. Phys Med Biol 2021; 66. [PMID: 34181588 DOI: 10.1088/1361-6560/ac0f2f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/28/2021] [Indexed: 11/11/2022]
Abstract
Dynamic CT myocardial perfusion imaging (DCT-MPI) is a reliable examination tool for the assessment of myocardium and vascular, while its special scan protocol may result in excessive radiation exposure to patients and inevitable inter-frame motion. Lowering the tube current is a simple way to reduce radiation exposure. However, low mAs will certainly cause severe image noise, thus may further impact the accuracy of functional hemodynamic parameters, which are used for the assessment of blood supply. In this work, we present a novel scheme applying motion compensation and local low rank regularization (MC-LLR) for obtaining high quality motion compensated DCT-MPI images. Specifically, motion compensation by using robust data decomposition registration (RDDR) was introduced. Robust principal component analysis coupled with optical flow-based registration algorithm were used in RDDR. Then, the local low rank constraint on the motion compensated time series images was applied for the DCT-MPI reconstruction. One healthy mini pig and two patient datasets were used to evaluate the proposed MC-LLR algorithm. Results show that the present method achieved satisfactory image quality with higher CNRs, smaller rRMSEs, and more accurate hemodynamic parameter maps.
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Affiliation(s)
- Jia Liu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Shuang Jin
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Qian Li
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Kunpeng Zhang
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Jiahong Yu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Ying Mo
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Zhaoying Bian
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Yang Gao
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
| | - Hua Zhang
- School of Biomedical Engineering, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Provincial Key Laboratory of Medical Image Processing, Southern Medical University, Guangzhou, People's Republic of China.,Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, People's Republic of China
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13
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Sundell VM, Kortesniemi M, Siiskonen T, Kosunen A, Rosendahl S, Büermann L. PATIENT-SPECIFIC DOSE ESTIMATES IN DYNAMIC COMPUTED TOMOGRAPHY MYOCARDIAL PERFUSION EXAMINATION. RADIATION PROTECTION DOSIMETRY 2021; 193:24-36. [PMID: 33693932 PMCID: PMC8227483 DOI: 10.1093/rpd/ncab016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 12/09/2020] [Accepted: 01/26/2021] [Indexed: 05/07/2023]
Abstract
The study aimed to implement realistic source models of a computed tomography (CT) scanner and Monte Carlo simulations to actual patient data and to calculate patient-specific organ and effective dose estimates for patients undergoing dynamic CT myocardial perfusion examinations. Source models including bowtie filter, tube output and x-ray spectra were determined for a dual-source Siemens Somatom Definition Flash scanner. Twenty CT angiography patient datasets were merged with a scaled International Commission on Radiological Protection (ICRP) 110 voxel phantom. Dose simulations were conducted with ImpactMC software. Effective dose estimates varied from 5.0 to 14.6 mSv for the 80 kV spectrum and from 8.9 to 24.7 mSv for the 100 kV spectrum. Significant differences in organ doses and effective doses between patients emphasise the need to use actual patient data merged with matched anthropomorphic anatomy in the dose simulations to achieve a reasonable level of accuracy in the dose estimation procedure.
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Affiliation(s)
- V-M Sundell
- HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Uusimaa, Finland
- Department of Physics, University of Helsinki, P.O. Box 64, 00014 University of Helsinki, Finland
| | - M Kortesniemi
- HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Uusimaa, Finland
| | - T Siiskonen
- STUK-Radiation and Nuclear Safety Authority, Laippatie 4, Helsinki 00880, Finland
| | - A Kosunen
- STUK-Radiation and Nuclear Safety Authority, Laippatie 4, Helsinki 00880, Finland
| | - S Rosendahl
- Department 6.2 Dosimetry for radiation therapy and diagnostic radiology, Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig 38116, Germany
| | - L Büermann
- Department 6.2 Dosimetry for radiation therapy and diagnostic radiology, Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig 38116, Germany
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14
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Omarov YA, Sukhinina TS, Veselova TN, Shakhnovich RM, Zhukova NS, Merkulova IN, Pevzner DV, Ternovoy SK, Staroverov II. [Possibilities of Stress Computed Tomography Myocardial Perfusion Imaging in the Diagnosis of Ischemic Heart Disease]. ACTA ACUST UNITED AC 2020; 60:122-131. [PMID: 33228515 DOI: 10.18087/cardio.2020.10.n1028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 02/17/2020] [Indexed: 11/18/2022]
Abstract
Computed tomography angiography (CT-angiography, CTA) allows noninvasive visualization of coronary arteries (CA). This method is highly sensitive in detecting coronary atherosclerosis. However, standard CTA does not allow evaluation of the hemodynamic significance of found CA stenoses, which requires additional functional tests for detection of myocardial ischemia. This review focuses on possibilities of clinical use, limitations, technical aspects, and prospects of a combination of CT-angiography and CT myocardial perfusion imaging in diagnostics of ischemic heart disease.
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Affiliation(s)
- Y A Omarov
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - T S Sukhinina
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - T N Veselova
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - R M Shakhnovich
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - N S Zhukova
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - I N Merkulova
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - D V Pevzner
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
| | - S K Ternovoy
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow; First Moscow State Medical University, Sechenov Moscow State Medical University (Sechenov University), Moscow
| | - I I Staroverov
- National Medical Research Center of Cardiology" of the Ministry of Health of Russia, Moscow
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15
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Schicchi N, Fogante M, Palumbo P, Agliata G, Esposto Pirani P, Di Cesare E, Giovagnoni A. The sub-millisievert era in CTCA: the technical basis of the new radiation dose approach. LA RADIOLOGIA MEDICA 2020; 125:1024-1039. [PMID: 32930945 DOI: 10.1007/s11547-020-01280-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022]
Abstract
Computed tomography coronary angiography (CTCA) has become a cornerstone in the diagnostic process of the heart disease. Although the cardiac imaging with interventional procedures is responsible for approximately 40% of the cumulative effective dose in medical imaging, a relevant radiation dose reduction over the last decade was obtained, with the beginning of the sub-mSv era in CTCA. The main technical basis to obtain a radiation dose reduction in CTCA is the use of a low tube voltage, the adoption of a prospective electrocardiogram-triggering spiral protocol and the application of the tube current modulation with the iterative reconstruction technique. Nevertheless, CTCA examinations are characterized by a wide range of radiation doses between different radiology departments. Moreover, the dose exposure in CTCA is extremely important because the benefit-risk calculus in comparison with other modalities also depends on it. Finally, because anatomical evaluation not adequately predicts the hemodynamic relevance of coronary stenosis, a low radiation dose in routine CTCA would allow the greatest use of the myocardial CT perfusion, fractional flow reserve-CT, dual-energy CT and artificial intelligence, to shift focus from morphological assessment to a comprehensive morphological and functional evaluation of the stenosis. Therefore, the aim of this work is to summarize the correct use of the technical basis in order that CTCA becomes an established examination for assessment of the coronary artery disease with low radiation dose.
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Affiliation(s)
- Nicolò Schicchi
- Radiology Department, Azienda Ospedaliero Universitaria "Ospedali Riuniti", 60126, Ancona, Italy
| | - Marco Fogante
- Radiology Department, Azienda Ospedaliero Universitaria "Ospedali Riuniti", 60126, Ancona, Italy.
| | - Pierpaolo Palumbo
- Radiology Department, Azienda Ospedaliero Universitaria "San Salvatore", 60126, L'Aquila, Italy
| | - Giacomo Agliata
- Radiology Department, Azienda Ospedaliero Universitaria "Ospedali Riuniti", 60126, Ancona, Italy
| | - Paolo Esposto Pirani
- Radiology Department, Azienda Ospedaliero Universitaria "Ospedali Riuniti", 60126, Ancona, Italy
| | - Ernesto Di Cesare
- Radiology Department, Azienda Ospedaliero Universitaria "San Salvatore", 60126, L'Aquila, Italy
| | - Andrea Giovagnoni
- Radiology Department, Azienda Ospedaliero Universitaria "Ospedali Riuniti", 60126, Ancona, Italy
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16
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Assen MV, Vonder M, Pelgrim GJ, Von Knebel Doeberitz PL, Vliegenthart R. Computed tomography for myocardial characterization in ischemic heart disease: a state-of-the-art review. Eur Radiol Exp 2020; 4:36. [PMID: 32548777 PMCID: PMC7297926 DOI: 10.1186/s41747-020-00158-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 03/30/2020] [Indexed: 12/21/2022] Open
Abstract
This review provides an overview of the currently available computed tomography (CT) techniques for myocardial tissue characterization in ischemic heart disease, including CT perfusion and late iodine enhancement. CT myocardial perfusion imaging can be performed with static and dynamic protocols for the detection of ischemia and infarction using either single- or dual-energy CT modes. Late iodine enhancement may be used for the analysis of myocardial infarction. The accuracy of these CT techniques is highly dependent on the imaging protocol, including acquisition timing and contrast administration. Additionally, the options for qualitative and quantitative analysis and the accuracy of each technique are discussed.
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Affiliation(s)
- M van Assen
- University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 EZ, Groningen, The Netherlands.
| | - M Vonder
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - G J Pelgrim
- Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - P L Von Knebel Doeberitz
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - R Vliegenthart
- Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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17
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Ko SM. Evaluation of Myocardial Ischemia Using Coronary Computed Tomography Angiography in Patients with Stable Angina. JOURNAL OF THE KOREAN SOCIETY OF RADIOLOGY 2020; 81:250-271. [PMID: 36237390 PMCID: PMC9431814 DOI: 10.3348/jksr.2020.81.2.250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 03/20/2020] [Accepted: 03/29/2020] [Indexed: 11/20/2022]
Abstract
안정형 협심증 환자에서 관상동맥질환의 치료 여부를 결정하고 임상 결과를 예측하기 위해서는 심근허혈의 평가가 중요하다. 현재 심근허혈 진단의 표준검사법으로 분획혈류예비력 검사법이 인정되나 침습적 검사라는 제한점이 있다. 또한, 관상동맥 전산화단층촬영은 형태적인 관상동맥질환 진단에 유용한 방법으로 정립되었지만, 혈역학적으로 유의한 협착에 의한 심근허혈 진단에는 한계가 있다. 최근 이러한 문제를 해결하고자 관상동맥 전산화단층촬영 영상을 기반으로 측정한 관상동맥 죽상경화판의 정량화, 심근관류, 그리고 심근 분획혈류예비력을 이용한 연구들이 진행되어 왔고, 그 진단적 가치를 점차 인정받고 있다. 본 종설에서는 심근허혈진단과 관련된 관상동맥 전산화단층촬영 혈관조영술의 여러 영상기법들에 대해서 알아보고자 한다.
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Affiliation(s)
- Sung Min Ko
- Department of Radiology, Yonsei University Wonju College of Medicine, Wonju Severance Christian Hospital, Wonju, Korea
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18
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Computed tomography angiography-derived fractional flow reserve (CT-FFR) for the detection of myocardial ischemia with invasive fractional flow reserve as reference: systematic review and meta-analysis. Eur Radiol 2019; 30:712-725. [DOI: 10.1007/s00330-019-06470-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/21/2019] [Accepted: 09/19/2019] [Indexed: 12/22/2022]
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19
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Dynamic Quantitative Iodine Myocardial Perfusion Imaging with Dual-Layer CT using a Porcine Model. Sci Rep 2019; 9:16046. [PMID: 31690759 PMCID: PMC6831609 DOI: 10.1038/s41598-019-52458-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/16/2019] [Indexed: 01/09/2023] Open
Abstract
Ischemic heart disease is the globally leading cause of death. When using coronary CT angiography, the functional hemodynamics within the myocardium remain uncertain. In this study myocardial CT perfusion imaging using iodine contrast agent demonstrated to strongly improve the assessment of myocardial disorders. However, a retrieval of such dynamics using Hounsfield units from conventional CT poses concerns with respect to beam-hardening effects and low contrast-to-noise ratio (CNR). Dual-energy CT offers novel approaches to overcome aforementioned limitations. Quantitative peak enhancement, perfusion, time to peak and iodine volume measurements inside the myocardium were determined resulting in 0.92 mg/ml, 0.085 mg/ml/s 17.12 s and 29.89 mg/ml*s, respectively. We report on the first extensive quantitative and iodine-based analysis of myocardial dynamics in a healthy porcine model using a dual-layer spectral CT. We further elucidate on the potential of reducing the radiation dose from 135 to 18 mGy and the contrast agent volume from 60 to 30 mL by presenting a two-shot acquisition approach and measuring iodine concentrations in the myocardium in-vivo down to 1 mg/ml, respectively. We believe that dynamic quantitative iodine perfusion imaging may be a highly sensitive tool for the precise functional assessment and monitoring of early myocardial ischemia.
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20
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van Assen M, Pelgrim GJ, Slager E, van Tuijl S, Schoepf UJ, Vliegenthart R, Oudkerk M. Low CT temporal sampling rates result in a substantial underestimation of myocardial blood flow measurements. Int J Cardiovasc Imaging 2019; 35:539-547. [PMID: 30284642 PMCID: PMC6454077 DOI: 10.1007/s10554-018-1451-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 09/05/2018] [Indexed: 02/03/2023]
Abstract
The purpose of this study was to evaluate the effect of temporal sampling rate in dynamic CT myocardial perfusion imaging (CTMPI) on myocardial blood flow (MBF). Dynamic perfusion CT underestimates myocardial blood flow compared to PET and SPECT values. For accurate quantitative analysis of myocardial perfusion with dynamic perfusion CT a stable calibrated HU measurement of MBF is essential. Three porcine hearts were perfused using an ex-vivo Langendorff model. Hemodynamic parameters were monitored. Dynamic CTMPI was performed using third generation dual source CT at 70 kVp and 230-350 mAs/rot in electrocardiography(ECG)-triggered shuttle-mode (sampling rate, 1 acquisition every 2-3 s; z-range, 10.2 cm), ECG-triggered non-shuttle mode (fixed table position) with stationary tube rotation (1 acquisition every 0.5-1 s, 5.8 cm), and non-ECG-triggered continuous mode (1 acquisition every 0.06 s, 5.8 cm). Stenosis was created in the circumflex artery, inducing different fractional flow reserve values. Volume perfusion CT Myocardium software was used to analyze ECG-triggered scans. For the non-ECG triggered scans MASS research version was used combined with an in-house Matlab script. MBF (mL/g/min) was calculated for non-ischemic segments. True MBF was calculated using input flow and heart weight. Significant differences in MBF between shuttle, non-shuttle and continuous mode were found, with median MBF of 0.87 [interquartile range 0.72-1.00], 1.20 (1.07-1.30) and 1.65 (1.40-1.88), respectively. The median MBF in shuttle mode was 56% lower than the true MBF. In non-shuttle and continuous mode, the underestimation was 41% and 18%. Limited temporal sampling rate in standard dynamic CTMPI techniques contributes to substantial underestimation of true MBF.
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Affiliation(s)
- Marly van Assen
- Center for Medical Imaging-North East Netherlands, University of Groningen, University Medical Center Groningen, EB44, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Gert Jan Pelgrim
- Center for Medical Imaging-North East Netherlands, University of Groningen, University Medical Center Groningen, EB44, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Emmy Slager
- Center for Medical Imaging-North East Netherlands, University of Groningen, University Medical Center Groningen, EB44, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | | | | | - Rozemarijn Vliegenthart
- Department of Radiology, Center for Medical Imaging-North East Netherlands, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Matthijs Oudkerk
- Center for Medical Imaging-North East Netherlands, University of Groningen, University Medical Center Groningen, EB44, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
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21
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van Assen M, Pelgrim GJ, De Cecco CN, Stijnen JMA, Zaki BM, Oudkerk M, Vliegenthart R, Schoepf UJ. Intermodel disagreement of myocardial blood flow estimation from dynamic CT perfusion imaging. Eur J Radiol 2019; 110:175-180. [DOI: 10.1016/j.ejrad.2018.11.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/18/2018] [Accepted: 11/23/2018] [Indexed: 01/31/2023]
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22
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Feger S, Kendziorra C, Lukas S, Shaban A, Bokelmann B, Zimmermann E, Rief M, Dewey M. Effect of iterative reconstruction and temporal averaging on contour sharpness in dynamic myocardial CT perfusion: Sub-analysis of the prospective 4D CT perfusion pilot study. PLoS One 2018; 13:e0205922. [PMID: 30325969 PMCID: PMC6191149 DOI: 10.1371/journal.pone.0205922] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/02/2018] [Indexed: 12/11/2022] Open
Abstract
Purpose Myocardial computed tomography perfusion (CTP) allows the assessment of the functional relevance of coronary artery stenosis. This study investigates to what extent the contour sharpness of sequences acquired by dynamic myocardial CTP is influenced by the following noise reduction methods: temporal averaging and adaptive iterative dose reduction 3D (AIDR 3D). Materials and methods Dynamic myocardial CT perfusion was conducted in 29 patients at a dose level of 9.5±2.0 mSv and was reconstructed with both filtered back projection (FBP) and strong levels of AIDR 3D. Temporal averaging to reduce noise was performed as a post-processing step by combining two, three, four, six and eight original consecutive 3D datasets. We evaluated the contour sharpness at four distinct edges of the left-ventricular myocardium based on two different approaches: the distance between 25% and 75% of the maximal grey value (d) and the slope in the contour (m). Results Iterative reconstruction reduced contour sharpness: both measures of contour sharpness performed better for FBP than for AIDR 3D (d = 1.7±0.4 mm versus 2.0±0.5 mm, p>0.059 at all edges; m = 255.9±123.9 HU/mm versus 160.6±123.5 HU/mm; p<0.023 for all edges). Increasing levels of temporal averaging degraded contour sharpness. When FBP reconstruction was applied, contour sharpness was best without temporal averaging (d = 1.7±0.4 mm, m = 255.9±123.9 HU/mm) and poorest for the strongest levels of temporal averaging (d = 2.1±0.3 mm, m = 142.2±104.9 HU/mm; comparison between lowest and highest temporal averaging level: for d p>0.052 at all edges and for m p<0.001 at all edges). Conclusion The use of both temporal averaging and iterative reconstruction degrades objective contour sharpness parameters of dynamic myocardial CTP. Thus, further advances in image processing are needed to optimise contour sharpness of 4D myocardial CTP.
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Affiliation(s)
- Sarah Feger
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
| | - Carsten Kendziorra
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Steffen Lukas
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Ahmed Shaban
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Björn Bokelmann
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Elke Zimmermann
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Matthias Rief
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Marc Dewey
- Department of Radiology, Charité—Universitätsmedizin Berlin, Berlin, Germany
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23
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CT Myocardial Perfusion Imaging: A New Frontier in Cardiac Imaging. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7295460. [PMID: 30406139 PMCID: PMC6204157 DOI: 10.1155/2018/7295460] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/09/2018] [Indexed: 12/21/2022]
Abstract
The past two decades have witnessed rapid and remarkable technical improvement of multidetector computed tomography (CT) in both image quality and diagnostic accuracy. These improvements include higher temporal resolution, high-definition and wider detectors, the introduction of dual-source and dual-energy scanners, and advanced postprocessing. Current new generation multidetector row (≥64 slices) CT systems allow an accurate and reliable assessment of both coronary epicardial stenosis and myocardial CT perfusion (CTP) imaging at rest and during pharmacologic stress in the same examination. This novel application makes CT the unique noninvasive "one-stop-shop" method for a comprehensive assessment of both anatomical coronary atherosclerosis and its physiological consequences. Myocardial CTP imaging can be performed with different approaches such as static arterial first-pass imaging, and dynamic CTP imaging, with their own advantages and disadvantages. Static CTP can be performed using single-energy or dual-energy CT, employing qualitative or semiquantitative analysis. In addition, dynamic CTP can obtain quantitative data of myocardial blood flow and coronary flow reserve. The purpose of this review was to summarize all available evidence about the emerging role of myocardial CTP to identify ischemia-associated lesions, focusing on technical considerations, clinical applications, strengths, limitations, and the more promising future fields of interest in the broad spectra of ischemic heart disease.
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Gu C, Zeng D, Lin J, Li S, He J, Zhang H, Bian Z, Niu S, Zhang Z, Huang J, Chen B, Zhao D, Chen W, Ma J. Promote quantitative ischemia imaging via myocardial perfusion CT iterative reconstruction with tensor total generalized variation regularization. ACTA ACUST UNITED AC 2018; 63:125009. [DOI: 10.1088/1361-6560/aac7bd] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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[Redundancy information-induced image reconstruction for low-dose myocardial perfusion computed tomography]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:27-33. [PMID: 33177030 PMCID: PMC6765608 DOI: 10.3969/j.issn.1673-4254.2018.01.05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE In the clinic, myocardial perfusion computed tomography (MPCT) imaging is commonly used to detect and assess myocardial ischemia quantitatively. However, repeated scanning on the myocardial region in the cine mode will increase the radiation dose for patients. With lowering radiation dose, the quality of images are degraded by noise induced artifact, which hampers the diagnostic accuracy. Therefore, in this paper, we propose a redundancy information induced iterative reconstruction framework for high quality MPCT images at the case of low dose. METHODS MPCT images have redundant structural information within frames and highly similarity between adjacent frames. Inspired by the two properties, in this work we propose a penalized weighted least-squares (PWLS) model incorporating NLM and TV based hybrid constraints, which is referred to as PWLS-aviNLM-TV for simplicity. The proposed algorithm can effectively eliminate noise and artifacts by taking into account the similarity between adjacent frames and redundancy information within frames, which also can improve spatial resolution within frames and maintain temporal resolution. RESULTS The experimental results on the 4D extended cardiac-torso (XCAT) phantom and preclinical porcine dataset demonstrates that the PWLS-aviNLM-TV algorithm obtains better performance in terms of noise reduction and artifacts suppression than the PWLS-TV and PWLSaviNLM algorithm. Moreover, the proposed algorithm can preserve the edges and detail information thereby efficiently differentiate ischemia from myocardium. CONCLUSIONS The present redundancy information induced reconstruction algorithm can reconstruct high-quality images from low-dose MPCT for better clinical imaging diagnosis.
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Li Y, Speidel MA, Francois CJ, Chen GH. Radiation Dose Reduction in CT Myocardial Perfusion Imaging Using SMART-RECON. IEEE TRANSACTIONS ON MEDICAL IMAGING 2017; 36:2557-2568. [PMID: 28866488 DOI: 10.1109/tmi.2017.2747521] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this paper, a newly developed statistical model-based image reconstruction [referred to as Simultaneous Multiple Artifacts Reduction in Tomographic RECONstruction (SMART-RECON)] is applied to low dose computer tomography (CT) myocardial perfusion imaging (CT-MPI). This method uses the nuclear norm of the spatial-temporal image matrix of the CT-MPI images as a regularizer, rather than a conventional spatial regularizer that incorporates image smoothness, edge preservation, or spatial sparsity into the reconstruction. In addition to providing the needed noise reduction for low-dose CT-MPI, SMART-RECON provides images with spatial resolution and noise power spectrum (NPS) properties, which are independent of contrast and dose levels. Both numerical simulations and in vivo animal studies were performed to validate the proposed method. In these studies, it was found that: 1) quantitative accuracy of perfusion maps in CT-MPI was well maintained for radiation dose level as low as 10 mAs per image frame, compared with the reference standard of 200 mAs for conventional filtered backprojection; 2) flow-occluded myocardium in the porcine heart was well delineated by SMART-RECON at 10 mAs per frame when compared with model-based image reconstruction using spatial total variation (TV) as the regularizer (referred to as TV-SIR) or spatial-temporal TV (ST-TV-SIR); the CT-MPI results were confirmed with positron-emission tomography imaging; 3) image sharpness in SMART-RECON images was nearly independent of image contrast level and radiation dose level, in stark contrast to TV-SIR and ST-TV-SIR, which displayed a strong dependence on both image contrast and radiation dose levels; and 4) the structure of the dose-normalized NPS for the SMART-RECON method did not depend on dose, while the TV-SIR and ST-TV-SIR NPS structure was dose-dependent.
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Kolossváry M, Szilveszter B, Merkely B, Maurovich-Horvat P. Plaque imaging with CT-a comprehensive review on coronary CT angiography based risk assessment. Cardiovasc Diagn Ther 2017; 7:489-506. [PMID: 29255692 PMCID: PMC5716945 DOI: 10.21037/cdt.2016.11.06] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 12/08/2016] [Indexed: 01/07/2023]
Abstract
CT based technologies have evolved considerably in recent years. Coronary CT angiography (CTA) provides robust assessment of coronary artery disease (CAD). Early coronary CTA imaging-as a gate-keeper of invasive angiography-has focused on the presence of obstructive stenosis. Coronary CTA is currently the only non-invasive imaging modality for the evaluation of non-obstructive CAD, which has been shown to contribute to adverse cardiac events. Importantly, improved spatial resolution of CT scanners and novel image reconstruction algorithms enable the quantification and characterization of atherosclerotic plaques. State-of-the-art CT imaging can therefore reliably assess the extent of CAD and differentiate between various plaque features. Recent studies have demonstrated the incremental prognostic value of adverse plaque features over luminal stenosis. Comprehensive coronary plaque assessment holds potential to significantly improve individual risk assessment incorporating adverse plaque characteristics, the extent and severity of atherosclerotic plaque burden. As a result, several coronary CTA based composite risk scores have been proposed recently to determine patients at high risk for adverse events. Coronary CTA became a promising modality for the evaluation of functional significance of coronary lesions using CT derived fractional flow reserve (FFR-CT) and/or rest/dynamic myocardial CT perfusion. This could lead to substantial reduction in unnecessary invasive catheterization procedures and provide information on ischemic burden of CAD. Discordance between the degree of stenosis and ischemia has been recognized in clinical landmark trials using invasive FFR. Both lesion stenosis and composition are possibly related to myocardial ischemia. The evaluation of lesion-specific ischemia using combined functional and morphological plaque information could ultimately improve the diagnostic performance of CTA and thus patient care. In this review we aimed to summarize current evidence on comprehensive coronary artery plaque assessment using coronary CTA.
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Affiliation(s)
- Márton Kolossváry
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Bálint Szilveszter
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Béla Merkely
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Pál Maurovich-Horvat
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, Budapest, Hungary
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Baumann S, Kryeziu P, Rutsch M, Lossnitzer D. Coronary Computed Tomography Angiography. Interv Cardiol 2017. [DOI: 10.5772/67800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Tanabe Y, Kido T, Kurata A, Yokoi T, Fukuyama N, Uetani T, Nishiyama H, Kawaguchi N, Tahir E, Miyagawa M, Mochizuki T. Peak enhancement ratio of myocardium to aorta for identification of myocardial ischemia using dynamic myocardial computed tomography perfusion imaging. J Cardiol 2017; 70:565-570. [PMID: 28501269 DOI: 10.1016/j.jjcc.2017.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 03/24/2017] [Accepted: 04/05/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND This study aimed to evaluate the feasibility of peak enhancement (PE) ratio of myocardium to aorta (PER) derived from stress dynamic computed tomography myocardial perfusion imaging (CTP) for the detection of myocardial ischemia assessed by magnetic resonance (MR) imaging. METHODS Forty-four patients who underwent stress dynamic CTP and MR imaging were retrospectively evaluated. From the time-attenuation curve, myocardial PE, PER, and myocardial blood flow (MBF) were calculated on a segment-based analysis. The correlation between myocardial and aortic PE was assessed by Spearman's correlation, and the differences in myocardial PE and PER between normal and ischemic myocardium were assessed by the Mann-Whitney U-test. The diagnostic accuracies of myocardial PE, PER, and MBF for detecting myocardial ischemia were compared by receiver operating characteristic analysis. RESULTS Of 704 segments, 258 segments (37%) were diagnosed as myocardial ischemia with MR imaging. Myocardial and aortic PE were significantly correlated in both normal and ischemic segments (r=0.76 and 0.58; p<0.05, in each). The myocardial PE and PER of ischemic segments were significantly lower than those of normal segments (p<0.05, in each). Sensitivity and specificity were 61% [95% confidence interval (CI), 55-70%] and 83% (95% CI, 73-87%) for myocardial PE, 78% (67-88%) and 82% (95% CI, 70-91%) for PER, and 81% (95% CI, 73-87%) and 85% (95% CI, 79-92%) for MBF. There was a significantly larger area under the curve for PER (0.87; 95% CI, 0.84-0.90) and MBF (0.88; 95%CI, 0.85-0.91), compared to myocardial PE (0.75; 95% CI, 0.70-0.79) (p<0.05, in each). There was no significant difference in area under the curve between PER and MBF. CONCLUSIONS The semi-quantitative parameter of PER showed a high diagnostic accuracy for the detection of myocardial ischemia, comparable to that of MBF.
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Affiliation(s)
- Yuki Tanabe
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan.
| | - Teruhito Kido
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Akira Kurata
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Takahiro Yokoi
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Naoki Fukuyama
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Teruyoshi Uetani
- Department of Cardiovascular Internal Medicine, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Hikaru Nishiyama
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Naoto Kawaguchi
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Enver Tahir
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Masao Miyagawa
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
| | - Teruhito Mochizuki
- Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon City, Ehime, Japan
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