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van Cauteren YJM, Smulders MW, Theunissen RALJ, Gerretsen SC, Adriaans BP, Bijvoet GP, Mingels AMA, van Kuijk SMJ, Schalla S, Crijns HJGM, Kim RJ, Wildberger JE, Heijman J, Bekkers SCAM. Cardiovascular magnetic resonance accurately detects obstructive coronary artery disease in suspected non-ST elevation myocardial infarction: a sub-analysis of the CARMENTA Trial. J Cardiovasc Magn Reson 2021; 23:40. [PMID: 33752696 PMCID: PMC7983380 DOI: 10.1186/s12968-021-00723-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 02/02/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Invasive coronary angiography (ICA) is still the reference test in suspected non-ST elevation myocardial infarction (NSTEMI), although a substantial number of patients do not have obstructive coronary artery disease (CAD). Early cardiovascular magnetic resonance (CMR) may be a useful gatekeeper for ICA in this setting. The main objective was to investigate the accuracy of CMR to detect obstructive CAD in NSTEMI. METHODS This study is a sub-analysis of a randomized controlled trial investigating whether a non-invasive imaging-first strategy safely reduced the number of ICA compared to routine clinical care in suspected NSTEMI (acute chest pain, non-diagnostic electrocardiogram, high sensitivity troponin T > 14 ng/L), and included 51 patients who underwent CMR prior to ICA. A stepwise approach was used to assess the diagnostic accuracy of CMR to detect (1) obstructive CAD (diameter stenosis ≥ 70% by ICA) and (2) an adjudicated final diagnosis of acute coronary syndrome (ACS). First, in all patients the combination of cine, T2-weighted and late gadolinium enhancement (LGE) imaging was evaluated for the presence of abnormalities consistent with a coronary etiology in any sequence. Hereafter and only when the scan was normal or equivocal, adenosine stress-perfusion CMR was added. RESULTS Of 51 patients included (63 ± 10 years, 51% male), 34 (67%) had obstructive CAD by ICA. The sensitivity, specificity and overall accuracy of the first step to diagnose obstructive CAD were 79%, 71% and 77%, respectively. Additional vasodilator stress-perfusion CMR was performed in 19 patients and combined with step one resulted in an overall sensitivity of 97%, specificity of 65% and accuracy of 86%. Of the remaining 17 patients with non-obstructive CAD, 4 (24%) had evidence for a myocardial infarction on LGE, explaining the modest specificity. The sensitivity, specificity and overall accuracy to diagnose ACS (n = 43) were 88%, 88% and 88%, respectively. CONCLUSION CMR accurately detects obstructive CAD and ACS in suspected NSTEMI. Non-obstructive CAD is common with CMR still identifying an infarction in almost one-quarter of patients. CMR should be considered as an early diagnostic approach in suspected NSTEMI. TRIAL REGISTRATION The CARMENTA trial has been registered at ClinicalTrials.gov with identifier NCT01559467.
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Affiliation(s)
- Yvonne J M van Cauteren
- Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, The Netherlands
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Martijn W Smulders
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | | | - Suzanne C Gerretsen
- Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, The Netherlands
| | - Bouke P Adriaans
- Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, The Netherlands
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | | | - Alma M A Mingels
- Department of Clinical Chemistry, Maastricht UMC+, Maastricht, The Netherlands
| | - Sander M J van Kuijk
- Department of Clinical Epidemiology & Medical Technology Assessment (KEMTA), Maastricht UMC+, Maastricht, The Netherlands
| | - Simon Schalla
- Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, The Netherlands
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Harry J G M Crijns
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Raymond J Kim
- Duke Cardiovascular Magnetic Resonance Center, Duke University Medical Center, Durham, NC, USA
| | - Joachim E Wildberger
- Department of Radiology and Nuclear Medicine, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Jordi Heijman
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Sebastiaan C A M Bekkers
- Department of Cardiology, Maastricht UMC+, Maastricht, The Netherlands.
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
- Maastricht University Medical Center, P. Debyelaan 25, P.O. Box 5800, 6202 AZ, Maastricht, The Netherlands.
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Bogaert J, Eitel I. Role of cardiovascular magnetic resonance in acute coronary syndrome. Glob Cardiol Sci Pract 2016; 2015:24. [PMID: 26779508 PMCID: PMC4614331 DOI: 10.5339/gcsp.2015.24] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Accepted: 04/30/2015] [Indexed: 12/27/2022] Open
Affiliation(s)
- Jan Bogaert
- KU Leuven - University of Leuven, Department of Imaging and Pathology, Leuven, Belgium
| | - Ingo Eitel
- University Heart Center Lübeck, Medical Clinic II (Cardiology, Angiology, Intensive care medicine), Lübeck, Germany
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Saba L, Fellini F, De Filippo M. Diagnostic value of contrast-enhanced cardiac magnetic resonance in patients with acute coronary syndrome with normal coronary arteries. Jpn J Radiol 2015; 33:410-7. [DOI: 10.1007/s11604-015-0440-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 05/14/2015] [Indexed: 01/01/2023]
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de Mello RAF, Nacif MS, dos Santos AASMD, Cury RC, Rochitte CE, Marchiori E. Diagnostic performance of combined cardiac MRI for detection of coronary artery disease. Eur J Radiol 2011; 81:1782-9. [PMID: 21664778 DOI: 10.1016/j.ejrad.2011.05.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 05/14/2011] [Accepted: 05/19/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To evaluate the diagnostic performance of stress perfusion cardiac MR (CMR) for detecting significant CAD (≥70% narrowing) in comparison with invasive coronary angiography (ICA) as a reference standard. METHODS Examinations of 54 patients who underwent both stress perfusion CMR and ICA for investigation of CAD between 2007 and 2009 were evaluated. The CMR protocol included dipyridamole stress and rest perfusion, stress and rest cine MRI for assessment of ventricular function and delayed gadolinium enhancement for assessment of myocardial viability and detection of infarction. CMR interpretation was performed by 2 observers blinded to the results of ICA and the clinical history. RESULTS From a total of 54 patients, 37 (68.5%) showed significant CAD in 71 coronary territories. A perfusion defect was detected in 35 patients and in 69 coronary territories. Individual stress perfusion CMR evaluation showed the highest accuracy (83%) of the CMR techniques. The combined analysis using all sequences increased the overall accuracy of CMR to 87%. CONCLUSION Combination of perfusion and cine-MR during stress/rest, associated to delayed enhancement in the same protocol improves CMRI diagnostic accuracy and sensitivity for patients with significant coronary stenosis, and may therefore be helpful for risk stratification and defining treatment strategies.
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Makaryus AN, Wolff SD. Cardiac Magnetic Resonance Imaging. Interv Cardiol 2011. [DOI: 10.1002/9781444319446.ch13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Performance of adenosine "stress-only" perfusion MRI in patients without a history of myocardial infarction: a clinical outcome study. Int J Cardiovasc Imaging 2011; 28:109-15. [PMID: 21279694 PMCID: PMC3275729 DOI: 10.1007/s10554-010-9775-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 12/15/2010] [Indexed: 11/12/2022]
Abstract
To assess the diagnostic value of adenosine “stress-only” myocardial perfusion MR for ischemia detection as an indicator for coronary angiography in patients without a prior myocardial infarction and a necessity to exclude ischemia. Adenosine perfusion MRI was performed at 1.5 T in 139 patients with a suspicion of ischemia and no prior myocardial infarction. After 3 min of adenosine infusion a perfusion sequence was started. Patients with a perfusion defect were referred to coronary angiography (CAG). Patients with a normal perfusion were enrolled in follow-up. Fourteen out of 139 patients (10.1%) had a perfusion defect indicative of ischemia. These patients underwent a coronary angiogram, which showed complete agreement with the perfusion images. 125 patients with a normal myocardial perfusion entered follow-up (median 672 days, range 333–1287 days). In the first year of follow-up one Major Adverse Coronary Event (MACE) occurred and one patient had new onset chest pain with a confirmed coronary stenosis. Reaching a negative predictive value for MACE of 99.2% and for any coronary event of 98.4%. At 2 year follow-up no additional MACE occurred. Sensitivity of adenosine perfusion MR for MACE is 93.3% and specificity and positive predictive value are 100%. Adenosine myocardial perfusion MR for the detection of myocardial ischemia in a “stress-only” protocol in patients without prior myocardial infarctions, has a high diagnostic accuracy. This fast examination can play an important role in the evaluation of patients without prior myocardial infarctions and a necessity to exclude ischemia.
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Kang DK, Schoepf UJ, Bastarrika G, Nance JW, Abro JA, Ruzsics B. Dual-energy computed tomography for integrative imaging of coronary artery disease: principles and clinical applications. Semin Ultrasound CT MR 2010; 31:276-91. [PMID: 20691928 DOI: 10.1053/j.sult.2010.05.004] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The introduction of coronary CT angiography (cCTA) has reinvigorated the debate whether management of patients with suspected coronary artery disease (CAD) should be primarily based on physiological, functional versus anatomical testing. Anatomical testing (i.e., cCTA or invasive catheterization) enables direct visualization and grading of coronary artery stenoses but has shortcomings for gauging the hemodynamic significance of lesions for myocardial perfusion. Rest/stress myocardial perfusion imaging (MPI) has been extensively validated for assessing the clinical significance of CAD by demonstrating fixed or reversible perfusion defects but has only limited anatomical information. There is growing evidence that contrast medium enhanced dual-energy cCTA (DECT) has potential for the comprehensive analysis of coronary artery morphology as well as changes in myocardial perfusion. DECT exploits the fact that tissues in the human body and iodine-based contrast media have unique absorption characteristics when penetrated with different X-ray energy levels, which enables mapping the iodine (and thus blood) distribution within the myocardium. The purpose of this communication is to describe the practical application of this technology for the comprehensive diagnosis of ischemic heart disease. We examine recent scientific findings in the context of current pivotal transitions in cardiovascular disease management and demonstrate the potential of cardiac DECT for the integrative assessment of patients with known or suspected CAD within a single CT-based protocol.
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Affiliation(s)
- Doo Kyoung Kang
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC 29401, USA
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Lubbers DD, Kuijpers D, Bodewes R, Kappert P, Kerkhof M, van Ooijen PMA, Oudkerk M. Inter-observer variability of visual analysis of "stress"-only adenosine first-pass myocardial perfusion imaging in relation to clinical experience and reading criteria. Int J Cardiovasc Imaging 2010; 27:557-62. [PMID: 20882414 PMCID: PMC3101342 DOI: 10.1007/s10554-010-9703-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2010] [Accepted: 09/10/2010] [Indexed: 12/04/2022]
Abstract
To assess the inter-observer agreement of adenosine “stress”-only visual analysis of perfusion MR images in relation to experience and reading criteria. 106 adenosine perfusion MR examinations out of 350, 46 consecutive positive examinations and 60 randomly selected negative examinations were visually analysed by three individual readers (two residents and a technician) with different levels of experience. Readings (blinded for any information) were compared with the reading of an expert radiologist. After a month the examinations were presented again (randomly) without knowledge regarding the first readings. This time readings were performed with the systematical use of reading criteria. Agreement with the expert reading was good for the most experienced resident (k = 0.88). Kappa was 0.48 for the least experienced, and 0.57 for the technician. After the second systematical reading inter-observer agreement increased to 0.9, 0.68 and 0.77 respectively. Overall kappa increased from 0.59 to 0.71. The use of reading criteria significantly improved the performance of the least experienced reader (P = 0.01). Visual analysis of adenosine “stress”-only first-pass perfusion MR images has moderate to very good agreement. Performance is experience related, but the systematic use of reading criteria significantly increased performance for the least experienced observer.
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Affiliation(s)
- D D Lubbers
- Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
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Hamon M, Fau G, Née G, Ehtisham J, Morello R, Hamon M. Meta-analysis of the diagnostic performance of stress perfusion cardiovascular magnetic resonance for detection of coronary artery disease. J Cardiovasc Magn Reson 2010; 12:29. [PMID: 20482819 PMCID: PMC2890682 DOI: 10.1186/1532-429x-12-29] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Accepted: 05/19/2010] [Indexed: 02/09/2023] Open
Abstract
AIM Evaluation of the diagnostic accuracy of stress perfusion cardiovascular magnetic resonance for the diagnosis of significant obstructive coronary artery disease (CAD) through meta-analysis of the available data. METHODOLOGY Original articles in any language published before July 2009 were selected from available databases (MEDLINE, Cochrane Library and BioMedCentral) using the combined search terms of magnetic resonance, perfusion, and coronary angiography; with the exploded term coronary artery disease. Statistical analysis was only performed on studies that: (1) used a [greater than or equal to] 1.5 Tesla MR scanner; (2) employed invasive coronary angiography as the reference standard for diagnosing significant obstructive CAD, defined as a [greater than or equal to] 50% diameter stenosis; and (3) provided sufficient data to permit analysis. RESULTS From the 263 citations identified, 55 relevant original articles were selected. Only 35 fulfilled all of the inclusion criteria, and of these 26 presented data on patient-based analysis. The overall patient-based analysis demonstrated a sensitivity of 89% (95% CI: 88-91%), and a specificity of 80% (95% CI: 78-83%). Adenosine stress perfusion CMR had better sensitivity than with dipyridamole (90% (88-92%) versus 86% (80-90%), P = 0.022), and a tendency to a better specificity (81% (78-84%) versus 77% (71-82%), P = 0.065). CONCLUSION Stress perfusion CMR is highly sensitive for detection of CAD but its specificity remains moderate.
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Affiliation(s)
- Michèle Hamon
- Department of Radiology, University Hospital of Caen, France
- INSERM 919, Cyceron, Caen, France
| | - Georges Fau
- Department of Radiology, University Hospital of Caen, France
| | | | - Javed Ehtisham
- Department of Cardiology, University Hospital of Caen, France
| | - Rémy Morello
- Department of Statistics, University Hospital of Caen, France
| | - Martial Hamon
- Department of Cardiology, University Hospital of Caen, France
- INSERM 744, Institut Pasteur de Lille, France
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11
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Wagner GS, Hakacova N. Electrocardiographic measures of myocardial function and necrosis. JACC Cardiovasc Imaging 2009; 2:1195-7. [PMID: 19833309 DOI: 10.1016/j.jcmg.2009.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 08/18/2009] [Indexed: 11/29/2022]
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Abstract
Approximately two thirds of patients with heart failure have underlying coronary artery disease. In the setting of ischemic heart disease, cardiovascular magnetic resonance has demonstrated usefulness in two ways: for the detection of coronary artery disease and for the assessment of myocardial viability in consideration for revascularization. This article discusses the use of cardiovascular magnetic resonance for the detection of coronary artery disease. The purpose of this article is to provide readers with a brief overview of each of the cardiovascular magnetic resonance techniques, their relative strengths, and their relative weaknesses. Because adenosine stress cardiovascular magnetic resonance is currently the most widely used clinically, it is the primary focus of this article.
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Affiliation(s)
- Dipan J Shah
- Weill Cornell Medical College, New York, NY, USA.
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14
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Schwarz F, Ruzsics B, Schoepf UJ, Bastarrika G, Chiaramida SA, Abro JA, Brothers RL, Vogt S, Schmidt B, Costello P, Zwerner PL. Dual-energy CT of the heart--principles and protocols. Eur J Radiol 2008; 68:423-33. [PMID: 19008064 DOI: 10.1016/j.ejrad.2008.09.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Accepted: 09/09/2008] [Indexed: 12/18/2022]
Abstract
The introduction of coronary CT angiography (cCTA) has reinvigorated the debate whether management of patients with suspected coronary artery disease (CAD) should be primarily based on physiological versus anatomical testing. Anatomical testing (i.e., cCTA or invasive catheterization) enables direct visualization and grading of coronary artery stenoses but has shortcomings for gauging the hemodynamic significance of lesions for myocardial perfusion. Conversely, rest/stress myocardial perfusion imaging (MPI) has been extensively validated for assessing the clinical significance of CAD by demonstrating fixed or reversible perfusion defects but has only limited anatomical information. There is early evidence that contrast medium enhanced dual-energy cCTA (DECT) has potential for the comprehensive analysis of coronary artery morphology as well as changes in myocardial perfusion. DECT exploits the fact that tissues in the human body and iodine-based contrast media have unique absorption characteristics when penetrated with different X-ray energy levels, which enables mapping the iodine (and thus blood) distribution within the myocardium. The purpose of this communication is to describe the practical application of this emerging technology for the comprehensive diagnosis of coronary artery disease in the context of the currently used tomographic imaging modalities (cCTA, nuclear MPI, MR MPI).
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Affiliation(s)
- Florian Schwarz
- Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Drive, Charleston, SC 29401, USA
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Strzelczyk J, Attili A. Cardiac Magnetic Resonance Evaluation of Myocardial Viability and Ischemia. Semin Roentgenol 2008; 43:193-203. [DOI: 10.1053/j.ro.2008.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Nael K, Fenchel M, Saleh R, Finn JP. Cardiac MR imaging: new advances and role of 3T. Magn Reson Imaging Clin N Am 2008; 15:291-300, v. [PMID: 17893050 DOI: 10.1016/j.mric.2007.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Over the last decade, cardiac magnetic resonance imaging has increasingly evolved into a useful diagnostic tool among the radiology and cardiology communities. Ongoing improvements in MR imaging hardware, processing speed, and pulse sequence development have laid the foundation for rapid progress in cardiac MR imaging. This article summarizes developing techniques and technique-related aspects, and the advantages and possible pitfalls of 3T in particular.
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Affiliation(s)
- Kambiz Nael
- Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles, 10945 Le Conte Avenue, Suite # 3371, Los Angeles, CA 90095-7206, USA.
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Kim HW, Klem I, Kim RJ. Detection of Myocardial Ischemia by Stress Perfusion Cardiovascular Magnetic Resonance. Magn Reson Imaging Clin N Am 2007; 15:527-40, vi. [DOI: 10.1016/j.mric.2007.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Fenchel M, Franow A, Martirosian P, Engels M, Kramer U, Stauder NI, Helber U, Vogler H, Claussen CD, Miller S. 1 M Gd-chelate (gadobutrol) for multislice first-pass magnetic resonance myocardial perfusion imaging. Br J Radiol 2007; 80:884-92. [PMID: 17875598 DOI: 10.1259/bjr/34610669] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The aim of the study was to evaluate a 1 M gadolinium-chelate (gadobutrol) for first-pass MR myocardial perfusion examinations in patients with suspected coronary artery disease (CAD). In phantom studies, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) values of gadobutrol were compared with gadopentetate (Gd-DTPA). 25 consecutive patients with clinically suspected CAD were examined with dynamic rest/stress MR perfusion examinations using 0.05 mmol kg(-1) gadobutrol. Semi-quantitative evaluation of the myocardial perfusion was performed by calculating the myocardial perfusion reserve index (MPRI). Hypoperfused regions were correlated with data from X-ray coronary angiography. In phantom studies, SNR/CNR of gadobutrol-doped blood samples were consistently higher for all applied flip angles at concentrations < or =1.0 mmol L(-1) compared with Gd-DTPA. Assessment of 81 stress perfusion series with gadobutrol in 25 patients yielded a sensitivity of 82% and specificity of 91% for significant CAD. Combining the information from all perfusion series of one patient yielded a sensitivity of 89% and specificity of 94% on a per-vessel basis. Gadobutrol exhibited favourable signal properties in phantom studies. Rest/stress myocardial perfusion examinations using 1 M gadobutrol yielded high sensitivity and specificity in detection of malperfused areas (82% and 91%, respectively). This is comparable with recently published perfusion data using 0.5 M Gd-DTPA.
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Affiliation(s)
- M Fenchel
- Department of Diagnostic Radiology, Eberhard-Karls-University, Tuebingen, Germany.
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Nandalur KR, Dwamena BA, Choudhri AF, Nandalur MR, Carlos RC. Diagnostic performance of stress cardiac magnetic resonance imaging in the detection of coronary artery disease: a meta-analysis. J Am Coll Cardiol 2007; 50:1343-53. [PMID: 17903634 DOI: 10.1016/j.jacc.2007.06.030] [Citation(s) in RCA: 369] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 05/09/2007] [Accepted: 06/25/2007] [Indexed: 12/30/2022]
Abstract
OBJECTIVES The purpose of our study was to conduct an evidence-based evaluation of stress cardiac magnetic resonance imaging (MRI) in the diagnosis of coronary artery disease (CAD). BACKGROUND Stress cardiac MRI has recently emerged as a noninvasive method in the detection of CAD, with 2 main techniques in use: 1) perfusion imaging; and 2) stress-induced wall motion abnormalities imaging. METHODS We examined studies from January 1990 to January 2007 using MEDLINE and EMBASE. A study was included if it: 1) used stress MRI as a diagnostic test for CAD (> or =50% diameter stenosis); and 2) used catheter X-ray angiography as the reference standard. RESULTS Thirty-seven studies (2,191 patients) met the inclusion criteria, with 14 datasets (754 patients) using stress-induced wall motion abnormalities imaging and 24 datasets (1,516 patients) using perfusion imaging. Stress-induced wall motion abnormalities imaging demonstrated a sensitivity of 0.83 (95% confidence interval [CI] 0.79 to 0.88) and specificity of 0.86 (95% CI 0.81 to 0.91) on a patient level (disease prevalence = 70.5%). Perfusion imaging demonstrated a sensitivity of 0.91 (95% CI 0.88 to 0.94) and specificity of 0.81 (95% CI 0.77 to 0.85) on a patient level (disease prevalence = 57.4%). CONCLUSIONS In studies with high disease prevalence, stress cardiac MRI, using either technique, demonstrates overall good sensitivity and specificity for the diagnosis of CAD. However, limited data are available regarding use of either technique in populations with low disease prevalence.
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Affiliation(s)
- Kiran R Nandalur
- Department of Radiology, University of Michigan Health System, Ann Arbor, Michigan, USA.
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Ruan C, Yang SH, Cusi K, Gao F, Clarke GD. Contrast-Enhanced First-Pass Myocardial Perfusion Magnetic Resonance Imaging With Parallel Acquisition at 3.0 Tesla. Invest Radiol 2007; 42:352-60. [PMID: 17507805 DOI: 10.1097/01.rli.0000262566.89636.3f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Magnetic resonance imaging (MRI) at 3 T is significantly different than 1.5 T and needs to be optimized due to increased signal-to-noise ratio (SNR) and specific absorption ratio (SAR). This study tests the hypothesis that first-pass myocardial perfusion MRI using saturation recovery (SR)-TrueFISP with parallel imaging is superior to SR-TurboFLASH and a more achievable technique for clinical application at 3 T. MATERIALS AND METHODS Myocardial perfusion imaging was performed on 12 subjects using SR-TurboFLASH and SR-TrueFISP sequences combined with parallel imaging. Four myocardial slices were acquired and evaluated by image segmentation. Quality of the measurements was determined from SNR, contrast-to-noise ratio (CNR), enhancement-to-noise ratio (ENR), and myocardial perfusion upslope. Data were analyzed using a 2-way ANOVA with imaging method and segment number as the independent variables. RESULTS SNR, CNR, ENR, and upslope were significantly higher for SR-TrueFISP versus SR-TurboFLASH (P < 0.001). Significant differences in SNR, CNR, ENR, and upslope were found among the myocardial segments (P < 0.005). CONCLUSIONS Optimized SR-TrueFISP first-pass myocardial perfusion MRI at 3 T has superior image quality compared with SR-TurboFLASH, independent of the myocardial segment analyzed. However, coil sensitivity nonuniformities and dielectric resonance effects cause signal intensity differences between myocardial segments that must be accounted for when interpreting 3 T perfusion studies.
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Affiliation(s)
- Chun Ruan
- Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78284-6200, USA
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Merkle N, Wöhrle J, Grebe O, Nusser T, Kunze M, Kestler HA, Kochs M, Hombach V. Assessment of myocardial perfusion for detection of coronary artery stenoses by steady-state, free-precession magnetic resonance first-pass imaging. Heart 2007; 93:1381-5. [PMID: 17488772 PMCID: PMC2016921 DOI: 10.1136/hrt.2006.104232] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE To evaluate the diagnostic impact of magnetic resonance imaging (MRI) first-pass perfusion using steady-state, free-precession (SSFP) sequences with parallel imaging (SENSE) for detection of coronary stenoses. DESIGN Prospective observational study. SETTING University hospital, cardiac MRI and catheterisation laboratories. PATIENTS AND METHODS 228 patients were examined with coronary angiography and MRI (1.5 T Intera CV). A three-slice, short-axis SSFP perfusion scan with a saturation prepulse was performed during infusion of adenosine and at rest followed by myocardial scar (late enhancement) imaging. Gadolinium-DTPA was given at 0.1 mmol/kg body weight. Perfusion images were visually assessed. Analysis for myocardial hypoperfusion was done according to patient group and according to vessel. RESULTS Sensitivity, specificity and accuracy of MRI first-pass perfusion for detection of a coronary artery stenosis (>50% luminal narrowing) in the total patient group were 93.0%, 85.7%, 91.2% and for a significant lesion (>70% luminal narrowing) 96.1%, 72.0%, 88.2%, respectively. Based on 536 coronary artery territories without myocardial scar, the sensitivity of MRI perfusion analysis for detection of a significant lesion was for the left anterior descending artery 91.4%, for the circumflex artery 81.6% and for the right coronary artery 65.1% (p<0.001). CONCLUSIONS MRI first-pass perfusion analysis using an SSFP sequence with three myocardial slices was a highly accurate diagnostic method for detection of coronary artery stenoses. This MRI technique can be included in daily practice and has the potential to guide the indication for invasive coronary angiography.
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Affiliation(s)
- Nico Merkle
- Department of Internal Medicine II, University of Ulm, Robert-Koch-Strasse-8, 89081 Ulm, Germany
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Tsukiji M, Nguyen P, Narayan G, Hellinger J, Chan F, Herfkens R, Pauly JM, McConnell MV, Yang PC. Peri-infarct ischemia determined by cardiovascular magnetic resonance evaluation of myocardial viability and stress perfusion predicts future cardiovascular events in patients with severe ischemic cardiomyopathy. J Cardiovasc Magn Reson 2007; 8:773-9. [PMID: 17060098 DOI: 10.1080/10976640600737615] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND We assessed whether cardiovascular magnetic resonance imaging (CMR) of peri-infarct ischemia provides prognostic information in severe ischemic cardiomyopathy (ICM) patients referred for revascularization. METHODS Twenty-one patients with severe ICM were recruited prospectively for combined stress adenosine perfusion, late gadolinium enhancement, and rest perfusion studies. The patients were followed for in-hospital and post-discharge cardiovascular events. RESULTS During 12+/- 9.8 months follow-up, 67% of the patients with peri-infarct ischemia and 13% of the patients without peri-infarct ischemia had cardiovascular events (p = 0.03). CONCLUSION. In severe ICM patients, the presence of peri-infarct ischemia was associated with a higher incidence of cardiovascular events.
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Affiliation(s)
- Miwako Tsukiji
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University, Stanford, California, USA
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Kim HW, Klem I, Kim RJ. Detection of Myocardial Ischemia by Stress Perfusion Cardiovascular Magnetic Resonance. Cardiol Clin 2007; 25:57-70, vi. [PMID: 17478240 DOI: 10.1016/j.ccl.2007.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
With recent technical and clinical advances, adenosine stress perfusion MRI has evolved from a promising research tool to an everyday clinical test. This article reviews the current state of stress perfusion MRI. Specifically, it addresses the following topics: validation of stress perfusion MRI in preclinical studies, diagnostic performance in patients, imaging protocol, and image interpretation.
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Affiliation(s)
- Han W Kim
- Duke Cardiovascular Magnetic Resonance Center, Duke University Health Systems, Durham, NC 27710, USA.
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Magnetic Resonance Imaging of the Myocardium. CARDIOVASCULAR MEDICINE 2007. [DOI: 10.1007/978-1-84628-715-2_39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Abstract
Recent developments in magnetic resonance (MR) imaging of the heart have refocused attention on the potential of MR and continue to attract intense interest within the radiology and cardiology communities. Improvements in speed, image quality, reliability, and range of applications have evolved to the point where cardiac MR imaging is increasingly seen as a practical clinical tool. As is often the case with MR imaging, not all of the most powerful techniques are necessarily easy to master or understand, and many-nonspecialists and specialists alike-are challenged to stay abreast. This review covers some of the major milestones that have led to the current state of cardiac MR and attempts to put into context some concepts that, although technical, have a real impact on the diagnostic power of cardiac MR imaging. Topics discussed include functional imaging, myocardial viability and perfusion imaging, flow quantification, and coronary artery imaging. A review such as this can only scratch the surface of what is a dynamic interdisciplinary field, but the hope is that sufficient information and insight are provided to stimulate the motivated reader to take his or her interest to the next level.
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Affiliation(s)
- J Paul Finn
- Department of Radiological Sciences, David Geffen School of Medicine, University of California Los Angeles, 10945 Le Conte Ave, Suite 3371, Los Angeles, CA 90095-7206, USA.
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Bernhardt P, Engels T, Levenson B, Haase K, Albrecht A, Strohm O. Prediction of necessity for coronary artery revascularization by adenosine contrast-enhanced magnetic resonance imaging. Int J Cardiol 2006; 112:184-90. [PMID: 16271778 DOI: 10.1016/j.ijcard.2005.08.050] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Revised: 08/25/2005] [Accepted: 08/29/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Assessing myocardial first-pass wash-in during pharmacological induced stress allows detection of perfusion deficits and indicates stenotic coronary arteries (CA). The aim of our study was to demonstrate clinical relevance of contrast-enhanced stress magnetic resonance imaging (CMR) by predicting necessity of CA intervention. METHODS 738 patients with scheduled coronary angiography (CXA) were scanned in a 1.5 Tesla CMR scanner. After 3 min of adenosine infusion (140 microg/kg/min), first-pass kinetic of contrast agent was evaluated. Myocardial necrosis was visualized with "myocardial late enhancement (MLE)". Perfusion deficits were described as either "ischemia in viable myocardium", or "no relevant ischemia in viable myocardium" or as "ischemia in chronic myocardial infarction (CMI)" based on spatial and temporal extent of ischemia and of MLE. CXA was performed in all patients within 48 h after CMR and revascularization, if applicable, was performed. Angiograms were read by two independent and blinded investigators and matched with CMR findings. RESULTS 539 patients (73%) showed "ischemia in viable myocardium" and revascularization was performed in 513 patients (95%). In 111 patients with "no relevant ischemia in viable myocardium", revascularization was performed in only 5 patients (5%). In 88 patients classified as "ischemia in CMI", revascularization was performed in 14 patients (16%). Positive predictive value of CMR for CA intervention was 0.95, negative predictive value was 0.89, sensitivity was 0.96, and specificity was 0.87. CONCLUSION CMR allows clinical useful prediction of relevant CA disease with need for revascularization prior to CXA and may be used as non-invasive test for myocardial ischemia and viability to guide further therapy.
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Nieman K, Cury RC, Ferencik M, Nomura CH, Abbara S, Hoffmann U, Gold HK, Jang IK, Brady TJ. Differentiation of recent and chronic myocardial infarction by cardiac computed tomography. Am J Cardiol 2006; 98:303-8. [PMID: 16860013 DOI: 10.1016/j.amjcard.2006.01.101] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 01/31/2006] [Accepted: 01/31/2006] [Indexed: 12/18/2022]
Abstract
Clinical use of cardiac computed tomography is rapidly expanding, and its purpose may reach beyond noninvasive coronary angiography. We investigated the ability of 64-slice multidetector computed tomography to differentiate between recent and long-standing myocardial infarction (MI). Contrast-enhanced coronary computed tomographic (CT) scans (Siemens Sensation 64) of patients with a recent MI (< 7 days, n = 16), long-standing MI (> 12 months, n = 13), and no MI (n = 13) were retrospectively evaluated. To anticipate transmural variation of myocardial perfusion and to neutralize image noise, a series of thin, overlapping slices was created in parallel alignment to the myocardial wall. Within each of these slices, a small region of interest was placed at a constant in-plane position to measure the CT attenuation (Hounsfield units [HU]) at consecutive transmural locations of injured and normal remote myocardium. In addition, wall thickness and the myocardial cavity were measured. Significantly lower CT attenuation values were found in patients with long-standing MI (-13 +/- 37 HU) than in those with acute MI (26 +/- 26 HU) and normal controls (73 +/- 14 HU, p < 0.001). The attenuation difference between infarcted and remote myocardia was larger in patients with long-standing MI than in patients with recent MI (89 +/- 41 and 55 +/- 33 HU, respectively, p < 0.001). In addition, long-standing MI was associated with wall thinning (p < 0.01), and ventricular dilation (p < 0.05), whereas recent MI was not (p > 0.05). In conclusion, recent and long-standing MIs may be differentiated by computed tomography based on myocardial CT attenuation values and ventricular dimensions.
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Affiliation(s)
- Koen Nieman
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA.
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Cury RC, Cattani CAM, Gabure LAG, Racy DJ, de Gois JM, Siebert U, Lima SS, Brady TJ. Diagnostic performance of stress perfusion and delayed-enhancement MR imaging in patients with coronary artery disease. Radiology 2006; 240:39-45. [PMID: 16793971 DOI: 10.1148/radiol.2401051161] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively determine the accuracy of a combined magnetic resonance (MR) imaging approach (stress first-pass perfusion imaging followed by delayed-enhancement imaging) for depicting clinically significant coronary artery stenosis (> or = 70% stenosis) in patients suspected of having or known to have coronary artery disease (CAD), with coronary angiography serving as the reference standard. MATERIALS AND METHODS The committee on human research approved the study protocol, and all participants gave written informed consent. This study was HIPAA compliant. Forty-seven patients (38 men and nine women; mean age, 63 years +/- 5.3 [standard deviation]) scheduled for coronary angiography were prospectively enrolled: 33 were suspected of having CAD (group A) and 14 had experienced a previous myocardial infarction and were suspected of having new lesions (group B). The MR imaging protocol included cine function, gadolinium-enhanced stress and rest first-pass perfusion MR imaging, and delayed-enhancement MR imaging. Myocardial ischemia was defined as a segment with perfusion deficit at stress first-pass perfusion MR imaging and no hyperenhancement at delayed-enhancement imaging. Myocardial infarction was defined as an area with hyperenhancement at delayed-enhancement imaging. RESULTS One patient was excluded from analysis because of poor-quality MR images. Coronary angiography depicted significant stenosis in 30 of 46 patients (65%). In a per-vessel analysis (n = 138), stress first-pass perfusion MR imaging and delayed-enhancement imaging yielded sensitivity of 0.87, specificity of 0.89, and accuracy of 0.88, when compared with coronary angiography. The diagnostic accuracy of stress first-pass perfusion MR imaging and delayed-enhancement imaging was slightly better than that of stress and rest first-pass perfusion MR imaging in the entire population (0.88 vs 0.85), in group A (0.86 vs 0.82), and in group B (0.93 vs 0.90). CONCLUSION Stress first-pass perfusion MR imaging followed by delayed-enhancement imaging is an accurate method to depict significant coronary stenosis in patients suspected of having or known to have CAD.
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Affiliation(s)
- Ricardo C Cury
- Department of Radiology, Beneficencia Portuguesa Hospital, Sao Paulo, Brazil.
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Bernhardt P, Levenson B, Engels T, Strohm O. Contrast-enhanced adenosine-stress magnetic resonance imaging--feasibility and practicability of a protocol for detection or exclusion of ischemic heart disease in an outpatient setting. Clin Res Cardiol 2006; 95:461-7. [PMID: 16830268 DOI: 10.1007/s00392-006-0410-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Accepted: 05/22/2006] [Indexed: 11/28/2022]
Abstract
BACKGROUND Evaluating myocardial function, assessing ischemic myocardial areas and detecting myocardial viability are necessary diagnostic information for guiding further therapy in patients with angina. The aim of this study was to show feasibility and safety of a compiled contrast- enhanced magnetic resonance imaging (ceMRI) protocol providing the above mentioned diagnostic possibilities and to demonstrate its applicability in daily routine. METHODS Consecutive patients with angina were screened on a 1.5 Tesla system. Functional images in short and long axis orientation were acquired for each patient. First-pass kinetics of a gadolinium-based contrast agent (0.1 mmol/kg) were measured after three minutes of stress with adenosine infusion (140 microg/kg/min). 10 min after a second bolus injection of contrast agent "late enhancement" (MLE) sequences were acquired for the detection of myocardial necrosis. RESULTS We enrolled 3174 patients referred for ceMRI for detection or exclusion of ischemic heart disease. One patient experienced a major complication due to hyperventilation followed by grand mal seizure. In 1121 (35.3%) patients minor complications, such as mild chest pain or dyspnea (30%), temporarily and asymptomatic AV block (3%) or nausea (2%) could be observed under adenosine infusion. Hypoperfusion in more than one myocardial segment and affecting more than 1/3 of the myocardial wall diameter could be detected in 1972 (62%) patients. Subendocardial hypoperfusion with limited duration could be shown in 897 (28%) patients. In 305 (10%) patients hypoperfusion could be excluded. MLE could be seen in 532 (17%) patients. CONCLUSION This compiled ceMRI protocol is suitable for detection or exclusion of ischemic heart disease in an outpatient routine. We showed feasibility, applicability and safety of our protocol. CeMRI may serve as a useful surrogate for non-invasive diagnostics prior to invasive coronary angiography in many outpatients.
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Affiliation(s)
- P Bernhardt
- Cardiac MRI at the Hospital Agatharied, St.-Agatha-Str. 1, 83734 Hausham, Germany.
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30
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Huber A, Schoenberg SO, Spannagl B, Rieber J, Erhard I, Klauss V, Reiser MF. Single-shot inversion recovery TrueFISP for assessment of myocardial infarction. AJR Am J Roentgenol 2006; 186:627-33. [PMID: 16498088 DOI: 10.2214/ajr.04.0746] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The aim of the study was to assess the diagnostic accuracy of imaging the myocardium with a fast multislice inversion recovery 2D single-shot true fast imaging with steady-state precession (trueFISP) sequence during a single breath-hold in comparison with an established segmented inversion recovery turbo fast low-angle shot (turboFLASH) sequence. SUBJECTS AND METHODS Forty-three patients with myocardial infarction were examined on a 1.5-T MR system 10 min after administration of contrast material (gadodiamide, 0.2 mmol/kg) with a single-shot 2D multislice technique (single-shot inversion recovery trueFISP) that allows one to image the entire short axis during one breath-hold (18 heartbeats) and with a segmented 2D single-slice technique (inversion recovery turboFLASH) that requires one breath-hold per slice (12 heartbeats). Signal intensity was determined in normal myocardium, in infarcted myocardium, and in the left ventricle. The contrast-to-noise ratio (CNR) of normal and infarcted myocardium was determined. The areas of hyperintense infarctions on selected slices and the entire volumes were compared for both sequence techniques. RESULTS The inversion recovery trueFISP sequence has a lower CNR than the inversion recovery turboFLASH sequence (mean values, 10.0 vs 12.9, respectively; p = 0.005) for differentiation of viable from nonviable myocardium. The CNR of injured myocardium and blood in the left ventricular cavity also has a lower value for the multislice technique compared with the single-slice technique (0.6 vs 1.2, respectively; p = 0.045). Assessment of the area of infarction within one slice (r = 0.97, p < 0.002) and of the volume of the entire infarction (r = 0.96, p < 0.003) is possible with excellent correlation of both techniques. CONCLUSION Despite having a lower CNR, the inversion recovery 2D single-shot trueFISP sequence allows fast and accurate identification of the area and volume of infarction with high spatial resolution within a single breath-hold.
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Affiliation(s)
- Armin Huber
- Institut für Klinische Radiologie, Klinikum Grosshadern, Marchioninistrasse 15, Munich 81377, Germany
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Carme S, Maï W, Mazzadi A, Janier M, Revel D, Magnin I, Wiart M, Neyran B, Canet-Soulas E. Importance of Parametric Mapping and Deconvolution in Analyzing Magnetic Resonance Myocardial Perfusion Images. Invest Radiol 2006; 41:374-83. [PMID: 16523020 DOI: 10.1097/01.rli.0000197980.89673.4b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
AIM : We sought to improve the clinical interpretation of first-pass myocardial magnetic resonance perfusion. Parametric analyses of the myocardial distribution of the contrast agent have been proposed. The objective of the present study was to compare the effectiveness of visual analysis and of a parametric approach in an animal model under acquisition conditions as close as possible to clinical reality. METHOD : Experiments were conducted in vivo with various kinds of pharmacological stimulation in normal pigs and in pigs with stenosis of the left circumflex coronary artery. First-pass MR images and parametric maps were first assessed by medical experts. MR parameters, the myocardial signal intensity variation DeltaSI, ascending up-slope, and rMBF (blood flow calculated by fast discrete ARMA deconvolution) were then compared with blood flow measurements using radioactive microspheres. RESULTS AND CONCLUSIONS : Interobserver agreement was 57% and 81% and accuracy 53% and 81%, for visual and for parametric map analysis, respectively. For deconvolution parameters, a linear relationship y = 371 + 1.27x, r = 0.78 was obtained between rMBF calculated by ARMA and the radioactive microsphere blood flow. Moreover, the fast and robust parametric mapping of rMBF by the discrete ARMA method allows MR evaluation of myocardial perfusion independently of hemodynamic conditions.
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Affiliation(s)
- Sabin Carme
- CREATIS UMR 5515 CNRS, Hôpital Cardiologique and INSA, University of Lyon 1, France
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Rodrigues de Avila LF, Fernandes JL, Rochitte CE, Cerri GG, Filho JP. Perfusion Impairment in Patients with Normal-appearing Coronary Arteries: Identification with Contrast-enhanced MR Imaging. Radiology 2006; 238:464-72. [PMID: 16371584 DOI: 10.1148/radiol.2382041697] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively determine the feasibility of using first-pass magnetic resonance (MR) imaging to distinguish between myocardial segments in patients with coronary artery disease (CAD) of different degrees of obstruction and those in patients with normal-appearing coronary arteries. MATERIALS AND METHODS The study was approved by the institutional ethics committee, and all patients provided informed consent. First-pass contrast material-enhanced MR imaging was performed at rest and after the infusion of dipyridamole in 37 patients (29 men, eight women; mean age, 57.2 years +/- 10.5 [standard deviation]) who had positive exercise test results or a clinical history of CAD. Myocardial segments were divided into five groups according to the degree of obstruction in the supplying artery. Signal intensity upslope, peak signal intensity, and time to peak signal intensity, as well as hyperemia-to-rest (HR) ratios for each of these three variables, were analyzed for each segment by using a generalized linear model. RESULTS Signal intensity upslope in patients with normal coronary arteries at angiography was significantly higher than that in patients with CAD (P < .001). Signal intensity upslope for segments in patients without CAD was significantly different from that for normal-appearing segments in patients with CAD (P < .001). Signal intensity upslope (P < .05) and peak signal intensity (P < .01) enabled the differentiation of segments with more than 70% reduction in luminal diameter from those in all other groups. HR ratios demonstrated findings that were similar to those obtained by using each signal intensity variable alone. CONCLUSION First-pass MR imaging can be used to distinguish segments with different degrees of obstructive CAD. Importantly, MR imaging can help identify segments with impaired perfusion and normal-appearing coronary arteries in patients with CAD and can demonstrate obstructive lesions in other territories.
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Affiliation(s)
- Luíz Francisco Rodrigues de Avila
- Cardiovascular Magnetic Resonance Laboratory Heart Institute and Institute of Radiology, University of São Paulo Medical School, Coord Diagnostico por Imagem, Av Dr Enéas de Carvalho Aguiar 44, São Paulo, SP 05403-000, Brazil
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Huber A, Bauner K, Wintersperger BJ, Reeder SB, Stadie F, Mueller E, Schmidt M, Winnik E, Reiser MF, Schoenberg SO. Phase-Sensitive Inversion Recovery (PSIR) Single-Shot TrueFISP for Assessment of Myocardial Infarction at 3 Tesla. Invest Radiol 2006; 41:148-53. [PMID: 16428986 DOI: 10.1097/01.rli.0000195843.97582.f4] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The aim of the current study was to show if contrast-to-noise ratio (CNR) could be improved without loss of diagnostic accuracy if a phase-sensitive inversion recovery (PSIR) single-shot TrueFISP sequence is used at 3.0 T instead of 1.5 T. MATERIAL AND METHODS Ten patients with myocardial infarction were examined on a 1.5 T magnetic resonance (MR) system (Avanto, Siemens Medical Systems) and at a 3.0 T MR system. Imaging delayed contrast enhancement was started 10 minutes after application of contrast material. A phase-sensitive inversion recovery (PSIR) single-shot TrueFISP sequence was used at 1.5 and 3.0 T and compared with a segmented IR turboFLASH sequence at 1.5 T, which served as the reference method. Infarct volumes and CNR of infarction and normal myocardium were compared with the reference method. RESULTS The PSIR Single-Shot TrueFISP technique allows for imaging nine slices during a single breathhold without adaptation of the inversion time. The mean value of CNR between infarction and normal myocardium was 5.9 at 1.5 T and 12.2 at 3.0 T (magnitude images). The CNR mean value of the reference method was 8.4. The CNR mean value at 3.0 T was significantly (P = 0.03) higher than the mean value of the reference method. The correlation coefficients of the infarct volumes, determined with the PSIR single-shot TrueFISP technique at 1.5 T and at 3.0 T and compared with the reference method, were r = 0.96 (P = 0.001) and r = 0.99 (P = 0.0001). CONCLUSION The use of PSIR single-shot TrueFISP at 3.0 T allows for accurate detection and assessment of myocardial infarction. CNR is significantly higher at 3.0 T compared with 1.5 T. The PSIR single-shot technique at 3.0 T provides a higher CNR than the segmented reference technique at 1.5 T.
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Affiliation(s)
- Armin Huber
- Institut für Klinische Radiologie, Klinikum Grosshadern, München, Germany.
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Fenchel M, Helber U, Kramer U, Stauder NI, Franow A, Claussen CD, Miller S. Detection of regional myocardial perfusion deficit using rest and stress perfusion MRI: a feasibility study. AJR Am J Roentgenol 2005; 185:627-35. [PMID: 16120910 DOI: 10.2214/ajr.185.3.01850627] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Providing high temporal and spatial resolution, perfusion MRI is an attractive alternative to traditional radionuclide methods like SPECT and PET. Although first-pass perfusion MRI examinations have gained increasing attention during the past years, this technique still exhibits relatively low signal-to-noise ratio and cardiac coverage. Previous studies have suggested that refocused gradient sequence technology (e.g., true fast imaging with steady-state precession [FISP]) should improve perfusion MRI examinations. The aim of this study was to assess myocardial perfusion deficits in patients with proven coronary artery disease using a saturation recovery true FISP perfusion sequence. SUBJECTS AND METHODS Rest and stress perfusion MRI studies were performed in 22 patients with coronary artery disease at 1.5 T using a multislice saturation recovery true FISP sequence after the bolus injection of 0.025 mmol/kg of body weight of gadopentetate dimeglumine. The myocardium of each slice was divided into 12 radial segments with subdivision into subendocardial and subepicardial subregions. Myocardial perfusion was assessed semiquantitatively and independently for each subregion. The standard of reference for myocardial perfusion was SPECT. Delayed enhancement images were acquired after the injection of 0.15 mmol/kg of body weight of gadopentetate dimeglumine. RESULTS Sensitivity and specificity of perfusion MRI examinations for the detection of perfusion deficits were 81% and 89%, respectively, for the semiquantitative perfusion parameter upslope and 78% and 86% for the parameter peak signal intensity. More specifically, rest perfusion examinations were able to detect areas of infarction, whereas stress examinations increased the perfusion differences between normal and ischemic myocardial areas. Excellent correlation was observed between rest perfusion and late enhancement findings (r = 0.90). CONCLUSION In patients with single-vessel coronary artery disease, perfusion deficits can reliably be detected using a saturation recovery true FISP sequence. Semiquantitative perfusion parameters upslope and peak signal intensity yielded similar results.
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Affiliation(s)
- Michael Fenchel
- Department of Diagnostic Radiology, Eberhard-Karls-University, Tuebingen 72076, Germany
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Barnett K, Feldman JA. Noninvasive Imaging Techniques to Aid in the Triage of Patients with Suspected Acute Coronary Syndrome: A Review. Emerg Med Clin North Am 2005; 23:977-98. [PMID: 16199334 DOI: 10.1016/j.emc.2005.07.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The evaluation, treatment, and disposition of patients with symptoms suggestive of acute coronary syndrome (ACS) in the Emergency Department continues to be a clinical challenge. Many patients with suggestive symptoms are admitted to the hospital to rule out a myocardial infarction by serial enzyme tests and EKGs and receive an expedited work-up for ischemia. However, the diagnosis can be difficult, given the wide range of potentially atypical symptoms that can signal ACS, which remains a major clinical risk for patients and a liability risk for emergency physicians. This article reviews imaging technologies such as echocardiography and nuclear perfusion imaging used currently in the diagnosis of ACS and rapidly advancing technologies such as CT and MRI that may be able to visualize calcifications, plaques, occlusions, and infarctions noninvasively in real time. Some noninvasive tests used to complete an ischemia work-up after serial enzyme testing and EKGs, such as exercise EKG, stress echocardiography, and stress perfusion imaging, also are reviewed.
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Affiliation(s)
- Katrina Barnett
- Department of Emergency Medicine, Boston Medical Center/Boston University School of Medicine, MA 02118, USA
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Fenchel M, Franow A, Stauder NI, Kramer U, Helber U, Claussen CD, Miller S. Myocardial perfusion after angioplasty in patients suspected of having single-vessel coronary artery disease: improvement detected at rest-stress first-pass perfusion MR imaging--initial experience. Radiology 2005; 237:67-74. [PMID: 16126922 DOI: 10.1148/radiol.2371041026] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively assess myocardial perfusion before and after successful intervention in patients suspected of having single-vessel coronary artery disease by using a steady-state free precession (SSFP) perfusion magnetic resonance (MR) imaging sequence. MATERIALS AND METHODS Local ethics committee approval and informed consent were obtained. Rest-stress perfusion MR imaging studies were performed in 18 patients with coronary artery disease (12 men, six women; mean age, 58.6 years +/- 13.6 [standard deviation]; range, 30-79 years) at 1.5 T with a multisection saturation-recovery SSFP sequence and 0.025 mmol gadopentetate dimeglumine per kilogram of body weight. MR studies were performed before (n = 18), several days after (n = 18), and 8 months after (n = 10) coronary intervention. Nine patients underwent percutaneous transluminal coronary angioplasty (PTCA) alone, and nine patients underwent PTCA with stent placement. Myocardial perfusion reserve index (MPRI) was calculated by dividing results of myocardial perfusion at maximal vasodilation by results at rest. The standard for myocardial perfusion was technetium 99m tetrofosmin single photon emission computed tomography. Statistical significance was tested with univariate variance analysis and Student t tests. RESULTS In the area of the stenosed vessel, MPRI was 1.04 +/- 0.24 before treatment and 2.18 +/- 0.57 several days afterward (P < .001). In remote areas, MPRI was 2.42 +/- 0.44. In the stent group, MPRI increased by 156%, from 0.99 +/- 0.20 before stent placement to 2.53 +/- 0.53 after (P < .001). Similarly, in the PTCA only group, MPRI increased by 72%, from 1.08 +/- 0.27 before PTCA to 1.87 +/- 0.39 after (P < .001). At follow-up in patients without recurring chest pain, MPRI was 2.14 +/- 0.37 in the area of the treated artery and 2.29 +/- 0.47 in remote areas (P = .06). CONCLUSION The MPRI, derived from rest-stress examinations, can provide information on success of interventional procedures in stenosed coronary arteries.
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Affiliation(s)
- Michael Fenchel
- Department of Diagnostic Radiology, Division of Cardiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str 3, 72076 Tuebingen, Germany.
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Nikolaou K, Sanz J, Poon M, Wintersperger BJ, Ohnesorge B, Rius T, Fayad ZA, Reiser MF, Becker CR. Assessment of myocardial perfusion and viability from routine contrast-enhanced 16-detector-row computed tomography of the heart: preliminary results. Eur Radiol 2005; 15:864-71. [PMID: 15776243 DOI: 10.1007/s00330-005-2672-6] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2004] [Revised: 01/06/2005] [Accepted: 01/11/2005] [Indexed: 01/10/2023]
Abstract
To assess the diagnostic accuracy of 16-detector-row computed tomography (16DCT) of the heart in the assessment of myocardial perfusion and viability in comparison to stress perfusion magnetic resonance imaging (SP-MRI) and delayed-enhancement magnetic resonance imaging (DE-MRI). A number of 30 patients underwent both 16DCT and MRI of the heart. Contrast-enhanced 16DCT data sets were reviewed for areas of myocardium with reduced attenuation. Both CT and MRI data were examined by independent reviewers for the presence of myocardial perfusion defects or myocardial infarctions (MI). Volumetric analysis of the hypoperfusion areas in CT and the infarct sizes in DE-MRI were performed. According to MRI, myocardial infarctions were detected in 11 of 30 cases, and perfusion defects not corresponding to an MI were detected in six of 30 patients. CTA was able to detect ten of 11 MI correctly (sensitivity 91%, specificity 79%, accuracy 83%), and detected three of six hypoperfusions correctly (sensitivity 50%, specificity 92%, accuracy 79%). Assessing the volume of perfusion defects correlating to history of MI on the CT images, a systematic underestimation of the true infarct size as compared to the results of DE-MRI was found (P<0.01). Routine, contrast-enhanced 16-detector row CT of the heart can detect chronic myocardial infarctions in the majority of cases, but ischemic perfusion defects are not reliably detected under resting conditions.
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Affiliation(s)
- Konstantin Nikolaou
- Department of Clinical Radiology, Ludwig-Maximilians-University of Munich, Germany.
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Kaandorp TAM, Lamb HJ, Bax JJ, van der Wall EE, de Roos A. Magnetic resonance imaging of coronary arteries, the ischemic cascade, and myocardial infarction. Am Heart J 2005; 149:200-8. [PMID: 15846256 DOI: 10.1016/j.ahj.2004.07.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Theodorus A M Kaandorp
- Department of Radiology, Leiden University Medical Center, Leiden, Zuid-Holland, The Netherlands.
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Fenchel M, Kramer U, Helber U, Stauder NI, Franow A, Claussen CD, Miller S. Semiquantitative assessment of myocardial perfusion using magnetic resonance imaging: evaluation of appropriate thresholds and segmentation models. Invest Radiol 2004; 39:572-81. [PMID: 15308940 DOI: 10.1097/01.rli.0000133816.83192.38] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES The aim of the study was to determine optimal thresholds for semiquantitative perfusion parameters and to evaluate the influence of different segmentation models in detecting malperfused regions. MATERIAL AND METHODS In 6 healthy subjects and 13 patients with coronary artery disease, contrast-enhanced first-pass perfusion imaging was performed using a SR-TrueFISP-sequence. Thresholds for semiquantitative parameters were established, and different segmentation models of the left ventricular myocardium were tested. The standard of reference for patient studies was single photon emission computed tomography. RESULTS Optimal thresholds were determined in healthy subjects for the perfusion parameters upslope, AUC, and peak SI of mv-0.5*std, mv-1.5*std, and mv-1.0*std, respectively. Using the optimal threshold for each parameter/segmentation combination sensitivities and specificities of stress studies were between 66% and 93% and 77% and 92%, respectively. Subdivision of radial segments into subendo/subepicardial segments increased sensitivities for perfusion deficits. CONCLUSIONS Subdivision of radial myocardial segments is essential in analysis of magnetic resonance first-pass perfusion series. Semiquantitative perfusion parameters possess different sensitivities for the detection of perfusion deficits.
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Affiliation(s)
- Michael Fenchel
- Department of Diagnostic Radiology, Division of Cardiology, Eberhard-Karls-University, Tuebingen, Germany.
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Gupta A, Lee VS, Chung YC, Babb JS, Simonetti OP. Myocardial infarction: optimization of inversion times at delayed contrast-enhanced MR imaging. Radiology 2004; 233:921-6. [PMID: 15516607 DOI: 10.1148/radiol.2333032004] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Seventeen patients underwent magnetic resonance (MR) imaging for myocardial viability with a protocol approved by the institutional review board and gave written informed consent. Breath-hold cine inversion-recovery segmented k-space true fast imaging with steady-state precession sequence, referred to as inversion time (TI) mapping, was performed to determine optimal TI for myocardial infarction inversion-recovery imaging. From TI mapping, optimal TI was 180-315 msec 10-15 minutes after administration of 0.15 mmol/kg of gadolinium-based contrast material. At that optimal TI, relative signal intensity of infarcted myocardium compared with uninfarcted myocardium was maximal (mean +/- standard deviation, 297.8% +/- 86.5), whereas signal-to-noise ratio of uninfarcted myocardium was minimal (4.5 +/- 1.2). When applied to conventional myocardial infarction inversion-recovery imaging, optimal TI resulted in nulling of signal intensity of uninfarcted myocardium in all patients and in excellent conspicuity of infarcted myocardium in all nine patients with visible infarction.
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Affiliation(s)
- Ankur Gupta
- Department of Radiology-MRI, New York University Medical Center, 530 First Avenue, New York, NY 10016, USA
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Abstract
Rapid progress has been made in cardiac MRI (CMRI) over the past decade, which has firmly established it as a reliable and clinically important technique for assessment of cardiac structure, function, perfusion, and myocardial viability. Its versatility and accuracy is unmatched by any other individual imaging modality. CMRI is non-invasive and has high spatial resolution and avoids use of potentially nephrotoxic contrast agent or radiation. It has been extensively studied against other established non-invasive imaging modalities and has been shown to be superior in many scenarios, particularly with respect to assessment of cardiac and great vessel morphology and left ventricular function. Furthermore, its clinical use continues to expand with increasing experience and proliferation of CMRI centres. As worldwide prevalence of cardiovascular disease continues to rise, CMRI provides opportunity for improved and cost-effective non-invasive assessment. Continued progress in CMRI technology promises to further widen its clinical application in coronary imaging, myocardial perfusion, comprehensive assessment of valves, and plaque characterisation.
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Affiliation(s)
- Godwin Constantine
- British Heart Foundation Cardiac MRI Unit, General Infirmary at Leeds, Leeds, UK
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Abstract
This article reviews the current MR imaging literature with respect to ischemic heart disease and focuses on the clinical practicalities of cardiac MR imaging today.
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Perrin RL, Ivancevic MK, Kozerke S, Vallee JP. Comparative study of FAST gradient echo MRI sequences: Phantom study. J Magn Reson Imaging 2004; 20:1030-8. [PMID: 15558562 DOI: 10.1002/jmri.20205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
PURPOSE To investigate a balanced steady state free precession sequence (b-SSFP) under a large range of conditions and to compare its performance with other types of gradient echo sequences for dynamic imaging. MATERIALS AND METHODS Balanced turbo field echo (b-TFE; Philips Medical Systems, Best, The Netherlands) was investigated in vitro at a range of T2/T1 along with T1-contrast enhanced turbo field echo (T1-TFE) and turbo field echo (TFE) so that a comparison could be made. Performance was quantified in terms of the initial slope of the signal-to-noise ratio (SNR) vs. 1/T1 curve (sensitivity) and the range of 1/T1 before signal saturation (contrast dynamic range [CDR]). RESULTS The b-TFE sequence was found to best perform, in terms of an optimal CDR, with a 90 degrees flip angle (FA), saturation preparation, and short inversion time. Using these parameters, the sensitivity was also higher than that of the TFE sequence and T1-TFE sequence under their respective optimal conditions. For detection of small changes in contrast agent concentration (0.0-0.1 mM), b-TFE was also found to be the sequence of choice, with optimized parameters as follows, 90 degrees FA, shortest TR/TE, and no magnetization preparation. The smallest matrices gave the highest signal sensitivity for all three sequences. CONCLUSION The CDR of b-TFE was much narrower than that of T1-TFE but could be widened under optimized conditions. The sensitivity of the b-TFE technique was the highest of the three sequences under all conditions tested.
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Affiliation(s)
- Rosalind L Perrin
- Radiology Department, University Hospital of Geneva, Genève, Switzerland
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