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Varga-Szemes A, Muscogiuri G, Schoepf UJ, De Cecco CN, Wichmann JL, Mangold S, Caruso D, Fuller SR, Spottiswoode BS, van der Geest RJ, Suranyi P. Overview of Myocardial T1 Mapping Applications. CURRENT RADIOLOGY REPORTS 2015. [DOI: 10.1007/s40134-015-0114-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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102
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Baeßler B, Schaarschmidt F, Stehning C, Schnackenburg B, Maintz D, Bunck AC. Cardiac T2-mapping using a fast gradient echo spin echo sequence - first in vitro and in vivo experience. J Cardiovasc Magn Reson 2015; 17:67. [PMID: 26231927 PMCID: PMC4522069 DOI: 10.1186/s12968-015-0177-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 07/24/2015] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND The aim of this study was the evaluation of a fast Gradient Spin Echo Technique (GraSE) for cardiac T2-mapping, combining a robust estimation of T2 relaxation times with short acquisition times. The sequence was compared against two previously introduced T2-mapping techniques in a phantom and in vivo. METHODS Phantom experiments were performed at 1.5 T using a commercially available cylindrical gel phantom. Three different T2-mapping techniques were compared: a Multi Echo Spin Echo (MESE; serving as a reference), a T2-prepared balanced Steady State Free Precession (T2prep) and a Gradient Spin Echo sequence. For the subsequent in vivo study, 12 healthy volunteers were examined on a clinical 1.5 T scanner. The three T2-mapping sequences were performed at three short-axis slices. Global myocardial T2 relaxation times were calculated and statistical analysis was performed. For assessment of pixel-by-pixel homogeneity, the number of segments showing an inhomogeneous T2 value distribution, as defined by a pixel SD exceeding 20 % of the corresponding observed T2 time, was counted. RESULTS Phantom experiments showed a greater difference of measured T2 values between T2prep and MESE than between GraSE and MESE, especially for species with low T1 values. Both, GraSE and T2prep resulted in an overestimation of T2 times compared to MESE. In vivo, significant differences between mean T2 times were observed. In general, T2prep resulted in lowest (52.4 ± 2.8 ms) and GraSE in highest T2 estimates (59.3 ± 4.0 ms). Analysis of pixel-by-pixel homogeneity revealed the least number of segments with inhomogeneous T2 distribution for GraSE-derived T2 maps. CONCLUSIONS The GraSE sequence is a fast and robust sequence, combining advantages of both MESE and T2prep techniques, which promises to enable improved clinical applicability of T2-mapping in the future. Our study revealed significant differences of derived mean T2 values when applying different sequence designs. Therefore, a systematic comparison of different cardiac T2-mapping sequences and the establishment of dedicated reference values should be the goal of future studies.
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Affiliation(s)
- Bettina Baeßler
- Department of Radiology, University Hospital of Cologne, Kerpener Str. 62, D-50937, Cologne, Germany.
| | - Frank Schaarschmidt
- Institute of Biostatistics, Faculty of Natural Sciences, Leibniz Universität Hannover, Hannover, Germany.
| | | | | | - David Maintz
- Department of Radiology, University Hospital of Cologne, Kerpener Str. 62, D-50937, Cologne, Germany.
| | - Alexander C Bunck
- Department of Radiology, University Hospital of Cologne, Kerpener Str. 62, D-50937, Cologne, Germany.
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103
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Macias C, Nakamura K, Tung R, Boyle NG, Kalyanam S, Bradfield JS. Importance Of Delayed Enhanced Cardiac MRI In Idiopathic RVOT-VT: Differentiating Mimics Including Early Stage ARVC And Cardiac Sarcoidosis. J Atr Fibrillation 2014; 7:1097. [PMID: 27957128 DOI: 10.4022/jafib.1097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/09/2014] [Accepted: 10/27/2014] [Indexed: 12/11/2022]
Abstract
A detailed understanding of cardiac anatomy and pathophysiology is necessary to optimize catheter ablation procedural success for patients with symptomatic ventricular tachycardia (VT)/premature ventricular contractions (PVCs) of outflow tract origin. Comprehensive imaging with cardiac magnetic resonance imaging (cMRI) is now at the forefront of procedural planning for complex ventricular arrhythmia ablation for patients with structural heart disease, but is increasingly used in patients with presumed "idiopathic" outflow VT/PVCs as well. cMRI with late gadolinium enhancement (LGE) can localize small regions of myocardial scar from previous myocardial infarction, fibrosis from non-ischemic cardiomyopathy, or edema/fibrosis from inflammatory disorders and help define targets for ablation. LGE, in combination with structural assessment, can help differentiate true idiopathic outflow VT/PVCs from those caused by early stage disease secondary to more significant pathology, such as arrhythmogenic right ventricular cardiomyopathy or cardiac sarcoidosis. We review the benefits of cMRI with LGE for patients with VT/PVCs of outflow origin.
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Affiliation(s)
- Carlos Macias
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Keijiro Nakamura
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Roderick Tung
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Noel G Boyle
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Shivkumar Kalyanam
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Jason S Bradfield
- UCLA Cardiac Arrhythmia Center, Ronald Reagan UCLA Health System, David Geffen School of Medicine at UCLA, Los Angeles, CA
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105
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Ferreira VM, Piechnik SK, Dall’Armellina E, Karamitsos TD, Francis JM, Ntusi N, Holloway C, Choudhury RP, Kardos A, Robson MD, Friedrich MG, Neubauer S. Native T1-mapping detects the location, extent and patterns of acute myocarditis without the need for gadolinium contrast agents. J Cardiovasc Magn Reson 2014; 16:36. [PMID: 24886708 PMCID: PMC4041901 DOI: 10.1186/1532-429x-16-36] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 05/02/2014] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Acute myocarditis can be diagnosed on cardiovascular magnetic resonance (CMR) using multiple techniques, including late gadolinium enhancement (LGE) imaging, which requires contrast administration. Native T1-mapping is significantly more sensitive than LGE and conventional T2-weighted (T2W) imaging in detecting myocarditis. The aims of this study were to demonstrate how to display the non-ischemic patterns of injury and to quantify myocardial involvement in acute myocarditis without the need for contrast agents, using topographic T1-maps and incremental T1 thresholds. METHODS We studied 60 patients with suspected acute myocarditis (median 3 days from presentation) and 50 controls using CMR (1.5 T), including: (1) dark-blood T2W imaging; >(2) native T1-mapping (ShMOLLI); (3) LGE. Analysis included: (1) global myocardial T2 signal intensity (SI) ratio compared to skeletal muscle; (2) myocardial T1 times; (3) areas of injury by T2W, T1-mapping and LGE. RESULTS Compared to controls, patients had more edema (global myocardial T2 SI ratio 1.71 ± 0.27 vs.1.56 ± 0.15), higher mean myocardial T1 (1011 ± 64 ms vs. 946 ± 23 ms) and more areas of injury as detected by T2W (median 5% vs. 0%), T1 (median 32% vs. 0.7%) and LGE (median 11% vs. 0%); all p < 0.001. A threshold of T1 > 990 ms (sensitivity 90%, specificity 88%) detected significantly larger areas of involvement than T2W and LGE imaging in patients, and additional areas of injury when T2W and LGE were negative. T1-mapping significantly improved the diagnostic confidence in an additional 30% of cases when at least one of the conventional methods (T2W, LGE) failed to identify any areas of abnormality. Using incremental thresholds, T1-mapping can display the non-ischemic patterns of injury typical of myocarditis. CONCLUSION Native T1-mapping can display the typical non-ischemic patterns in acute myocarditis, similar to LGE imaging but without the need for contrast agents. In addition, T1-mapping offers significant incremental diagnostic value, detecting additional areas of myocardial involvement beyond T2W and LGE imaging and identified extra cases when these conventional methods failed to identify abnormalities. In the future, it may be possible to perform gadolinium-free CMR using cine and T1-mapping for tissue characterization and may be particularly useful for patients in whom gadolinium contrast is contraindicated.
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Affiliation(s)
- Vanessa M Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Stefan K Piechnik
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Erica Dall’Armellina
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Theodoros D Karamitsos
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Jane M Francis
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Ntobeko Ntusi
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Cameron Holloway
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Robin P Choudhury
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Attila Kardos
- Department of Cardiology, Milton Keynes NHS Hospital Foundation Trust, Milton Keynes MK6 5LD, UK
| | - Matthew D Robson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Matthias G Friedrich
- Montreal Heart Institute, Departments of Medicine and Radiology, Université de Montréal, Montréal, QC H1T 1C8, Canada
- Stephenson Cardiovascular MR Centre, Libin Cardiovascular Institute of Alberta, Calgary, AB T2N 2 T9, Canada
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
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