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Nielles-Vallespin S, Khalique Z, Ferreira PF, de Silva R, Scott AD, Kilner P, McGill LA, Giannakidis A, Gatehouse PD, Ennis D, Aliotta E, Al-Khalil M, Kellman P, Mazilu D, Balaban RS, Firmin DN, Arai AE, Pennell DJ. Assessment of Myocardial Microstructural Dynamics by In Vivo Diffusion Tensor Cardiac Magnetic Resonance. J Am Coll Cardiol 2017; 69:661-676. [PMID: 28183509 PMCID: PMC8672367 DOI: 10.1016/j.jacc.2016.11.051] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 10/29/2016] [Accepted: 11/07/2016] [Indexed: 01/23/2023]
Abstract
BACKGROUND Cardiomyocytes are organized in microstructures termed sheetlets that reorientate during left ventricular thickening. Diffusion tensor cardiac magnetic resonance (DT-CMR) may enable noninvasive interrogation of in vivo cardiac microstructural dynamics. Dilated cardiomyopathy (DCM) is a condition of abnormal myocardium with unknown sheetlet function. OBJECTIVES This study sought to validate in vivo DT-CMR measures of cardiac microstructure against histology, characterize microstructural dynamics during left ventricular wall thickening, and apply the technique in hypertrophic cardiomyopathy (HCM) and DCM. METHODS In vivo DT-CMR was acquired throughout the cardiac cycle in healthy swine, followed by in situ and ex vivo DT-CMR, then validated against histology. In vivo DT-CMR was performed in 19 control subjects, 19 DCM, and 13 HCM patients. RESULTS In swine, a DT-CMR index of sheetlet reorientation (E2A) changed substantially (E2A mobility ~46°). E2A changes correlated with wall thickness changes (in vivo r2 = 0.75; in situ r2 = 0.89), were consistently observed under all experimental conditions, and accorded closely with histological analyses in both relaxed and contracted states. The potential contribution of cyclical strain effects to in vivo E2A was ~17%. In healthy human control subjects, E2A increased from diastole (18°) to systole (65°; p < 0.001; E2A mobility = 45°). HCM patients showed significantly greater E2A in diastole than control subjects did (48 ; p < 0.001) with impaired E2A mobility (23°; p < 0.001). In DCM, E2A was similar to control subjects in diastole, but systolic values were markedly lower (40° ; p < 0.001) with impaired E2A mobility (20°; p < 0.001). CONCLUSIONS Myocardial microstructure dynamics can be characterized by in vivo DT-CMR. Sheetlet function was abnormal in DCM with altered systolic conformation and reduced mobility, contrasting with HCM, which showed reduced mobility with altered diastolic conformation. These novel insights significantly improve understanding of contractile dysfunction at a level of noninvasive interrogation not previously available in humans. (J Am Coll Cardiol 2017;69:661–76) Published by Elsevier on behalf of the American College of Cardiology Foundation.
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Affiliation(s)
- Sonia Nielles-Vallespin
- National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland; Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom.
| | - Zohya Khalique
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Pedro F Ferreira
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Ranil de Silva
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Andrew D Scott
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Philip Kilner
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Laura-Ann McGill
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Archontis Giannakidis
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Peter D Gatehouse
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Daniel Ennis
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Eric Aliotta
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Majid Al-Khalil
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom
| | - Peter Kellman
- National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland
| | - Dumitru Mazilu
- National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland
| | - Robert S Balaban
- National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland
| | - David N Firmin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
| | - Andrew E Arai
- National Heart, Lung, and Blood Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland
| | - Dudley J Pennell
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Imperial College London, London, United Kingdom; National Institute for Health Research Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield National Health Service Foundation Trust, and Imperial College London, London, United Kingdom
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Tunnicliffe EM, Ferreira P, Scott AD, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin D. Intercentre reproducibility of second eigenvector orientation in cardiac diffusion tensor imaging. J Cardiovasc Magn Reson 2016. [PMCID: PMC5032190 DOI: 10.1186/1532-429x-18-s1-p35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Alam MH, Auger D, McGill LA, Smith GC, He T, Izgi C, Baksi AJ, Wage R, Drivas P, Firmin DN, Pennell DJ. Comparison of 3 T and 1.5 T for T2* magnetic resonance of tissue iron. J Cardiovasc Magn Reson 2016; 18:40. [PMID: 27391316 PMCID: PMC4938967 DOI: 10.1186/s12968-016-0259-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 06/22/2016] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND T2* magnetic resonance of tissue iron concentration has improved the outcome of transfusion dependant anaemia patients. Clinical evaluation is performed at 1.5 T but scanners operating at 3 T are increasing in numbers. There is a paucity of data on the relative merits of iron quantification at 3 T vs 1.5 T. METHODS A total of 104 transfusion dependent anaemia patients and 20 normal volunteers were prospectively recruited to undergo cardiac and liver T2* assessment at both 1.5 T and 3 T. Intra-observer, inter-observer and inter-study reproducibility analysis were performed on 20 randomly selected patients for cardiac and liver T2*. RESULTS Association between heart and liver T2* at 1.5 T and 3 T was non-linear with good fit (R (2) = 0.954, p < 0.001 for heart white-blood (WB) imaging; R (2) = 0.931, p < 0.001 for heart black-blood (BB) imaging; R (2) = 0.993, p < 0.001 for liver imaging). R2* approximately doubled between 1.5 T and 3 T with linear fits for both heart and liver (94, 94 and 105 % respectively). Coefficients of variation for intra- and inter-observer reproducibility, as well as inter-study reproducibility trended to be less good at 3 T (3.5 to 6.5 %) than at 1.5 T (1.4 to 5.7 %) for both heart and liver T2*. Artefact scores for the heart were significantly worse with the 3 T BB sequence (median 4, IQR 2-5) compared with the 1.5 T BB sequence (4 [3-5], p = 0.007). CONCLUSION Heart and liver T2* and R2* at 3 T show close association with 1.5 T values, but there were more artefacts at 3 T and trends to lower reproducibility causing difficulty in quantifying low T2* values with high tissue iron. Therefore T2* imaging at 1.5 T remains the gold standard for clinical practice. However, in centres where only 3 T is available, equivalent values at 1.5 T may be approximated by halving the 3 T tissue R2* with subsequent conversion to T2*.
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Affiliation(s)
- Mohammed H. Alam
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
- />Imperial College, London, UK
| | - Dominique Auger
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Laura-Ann McGill
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
- />Imperial College, London, UK
| | - Gillian C. Smith
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
- />Imperial College, London, UK
| | | | - Cemil Izgi
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - A. John Baksi
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Rick Wage
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - Peter Drivas
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - David N. Firmin
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
- />Imperial College, London, UK
| | - Dudley J. Pennell
- />NIHR Cardiovascular Biomedical Research Unit, Royal Brompton and Harefield NHS Foundation Trust, London, UK
- />Imperial College, London, UK
- />Royal Brompton Hospital, Sydney Street, London, SW3 6NP UK
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McGill LA, Ferreira P, Scott A, Nielles-Vallespin S, Kilner P, Silva RD, Firmin D, Pennell D. 134 Non-invasive Interrogation of Myocardial Disarray in Hypertrophic Cardiomyopathy. Heart 2016. [DOI: 10.1136/heartjnl-2016-309890.134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Scott AD, Nielles-Vallespin S, Ferreira PF, McGill LA, Pennell DJ, Firmin DN. The effects of noise in cardiac diffusion tensor imaging and the benefits of averaging complex data. NMR Biomed 2016; 29:588-599. [PMID: 26891219 DOI: 10.1002/nbm.3500] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 01/07/2016] [Accepted: 01/18/2016] [Indexed: 06/05/2023]
Abstract
There is growing interest in cardiac diffusion tensor imaging (cDTI), but, unlike other diffusion MRI applications, there has been little investigation of the effects of noise on the parameters typically derived. One method of mitigating noise floor effects when there are multiple image averages, as in cDTI, is to average the complex rather than the magnitude data, but the phase contains contributions from bulk motion, which must be removed first. The effects of noise on the mean diffusivity (MD), fractional anisotropy (FA), helical angle (HA) and absolute secondary eigenvector angle (E2A) were simulated with various diffusion weightings (b values). The effect of averaging complex versus magnitude images was investigated. In vivo cDTI was performed in 10 healthy subjects with b = 500, 1000, 1500 and 2000 s/mm(2). A technique for removing the motion-induced component of the image phase present in vivo was implemented by subtracting a low-resolution copy of the phase from the original images before averaging the complex images. MD, FA, E2A and the transmural gradient in HA were compared for un-averaged, magnitude- and complex-averaged reconstructions. Simulations demonstrated an over-estimation of FA and MD at low b values and an under-estimation at high b values. The transition is relatively signal-to-noise ratio (SNR) independent and occurs at a higher b value for FA (b = 1000-1250 s/mm(2)) than MD (b ≈ 250 s/mm(2)). E2A is under-estimated at low and high b values with a transition at b ≈ 1000 s/mm(2), whereas the bias in HA is comparatively small. The under-estimation of FA and MD at high b values is caused by noise floor effects, which can be mitigated by averaging the complex data. Understanding the parameters of interest and the effects of noise informs the selection of the optimal b values. When complex data are available, they should be used to maximise the benefit from the acquisition of multiple averages. The combination of complex data is also a valuable step towards segmented acquisitions.
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Affiliation(s)
- Andrew D Scott
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Sonia Nielles-Vallespin
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart Lung and Blood Institute, National Institutes for Health, Bethesda, MD, USA
| | - Pedro F Ferreira
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Laura-Ann McGill
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - Dudley J Pennell
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
| | - David N Firmin
- Cardiovascular Biomedical Research Unit, The Royal Brompton and Harefield NHS Foundation Trust and Imperial College, London, UK
- National Heart and Lung Institute, Imperial College, London, UK
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Scott AD, Nielles-Vallespin S, Ferreira P, Khalique Z, McGill LA, Kilner PJ, Pennell DJ, Firmin D. In-vivo cardiac DTI: An initial comparison of M012 compensated spin-echo and STEAM. J Cardiovasc Magn Reson 2016. [PMCID: PMC5032172 DOI: 10.1186/1532-429x-18-s1-w19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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McGill LA, Ferreira PF, Scott AD, Nielles-Vallespin S, Giannakidis A, Kilner PJ, Gatehouse PD, de Silva R, Firmin DN, Pennell DJ. Relationship between cardiac diffusion tensor imaging parameters and anthropometrics in healthy volunteers. J Cardiovasc Magn Reson 2016; 18:2. [PMID: 26738482 PMCID: PMC4704390 DOI: 10.1186/s12968-015-0215-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/03/2015] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND In vivo cardiac diffusion tensor imaging (cDTI) is uniquely capable of interrogating laminar myocardial dynamics non-invasively. A comprehensive dataset of quantative parameters and comparison with subject anthropometrics is required. METHODS cDTI was performed at 3T with a diffusion weighted STEAM sequence. Data was acquired from the mid left ventricle in 43 subjects during the systolic and diastolic pauses. Global and regional values were determined for fractional anisotropy (FA), mean diffusivity (MD), helix angle gradient (HAg, degrees/%depth) and the secondary eigenvector angulation (E2A). Regression analysis was performed between global values and subject anthropometrics. RESULTS All cDTI parameters displayed regional heterogeneity. The RR interval had a significant, but clinically small effect on systolic values for FA, HAg and E2A. Male sex and increasing left ventricular end diastolic volume were associated with increased systolic HAg. Diastolic HAg and systolic E2A were both directly related to left ventricular mass and body surface area. There was an inverse relationship between E2A mobility and both age and ejection fraction. CONCLUSIONS Future interpretations of quantitative cDTI data should take into account anthropometric variations observed with patient age, body surface area and left ventricular measurements. Further work determining the impact of technical factors such as strain and SNR is required.
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Affiliation(s)
- L A McGill
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - P F Ferreira
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - A D Scott
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - S Nielles-Vallespin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
| | - A Giannakidis
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - P J Kilner
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - P D Gatehouse
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - R de Silva
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - D N Firmin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
| | - D J Pennell
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP, UK.
- National Heart and Lung Institute, Imperial College, London, UK.
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Scott AD, Nielles-Vallespin S, Ferreira P, McGill LA, Pennell DJ, Firmin D. Improving the accuracy of cardiac DTI by averaging the complex data. J Cardiovasc Magn Reson 2015. [PMCID: PMC4328634 DOI: 10.1186/1532-429x-17-s1-o38] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Kilner PJ, McCarthy K, Murillo M, Ferreira P, Scott AD, McGill LA, Nielles-Vallespin S, Silva R, Pennell DJ, Ho SY, Firmin D. Histology of human myocardial laminar microstructure and consideration of its cyclic deformations with respect to interpretation of in vivo cardiac diffusion tensor imaging. J Cardiovasc Magn Reson 2015. [PMCID: PMC4328413 DOI: 10.1186/1532-429x-17-s1-q10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Scott AD, Ferreira P, Nielles-Vallespin S, McGill LA, Pennell DJ, Firmin D. Directions vs. averages: an in-vivo comparison for cardiac DTI. J Cardiovasc Magn Reson 2015. [PMCID: PMC4328355 DOI: 10.1186/1532-429x-17-s1-p25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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McGill LA, Scott AD, Ferreira P, Nielles-Vallespin S, Ismail TF, Kilner PJ, Gatehouse P, Prasad SK, Giannakidis A, Firmin D, Pennell DJ. Heterogeneity of diffusion tensor imaging measurements of fractional anisotropy and mean diffusivity in normal human hearts in vivo. J Cardiovasc Magn Reson 2015. [PMCID: PMC4328820 DOI: 10.1186/1532-429x-17-s1-o1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Kellman P, Xue H, Spottiswoode BS, Sandino CM, Hansen MS, Abdel-Gadir A, Treibel TA, Rosmini S, Mancini C, Bandettini WP, McGill LA, Gatehouse P, Moon JC, Pennell DJ, Arai AE. Free-breathing T2* mapping using respiratory motion corrected averaging. J Cardiovasc Magn Reson 2015; 17:3. [PMID: 25616857 PMCID: PMC4305251 DOI: 10.1186/s12968-014-0106-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 12/29/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pixel-wise T2* maps based on breath-held segmented image acquisition are prone to ghost artifacts in instances of poor breath-holding or cardiac arrhythmia. Single shot imaging is inherently immune to ghost type artifacts. We propose a free-breathing method based on respiratory motion corrected single shot imaging with averaging to improve the signal to noise ratio. METHODS Images were acquired using a multi-echo gradient recalled echo sequence and T2* maps were calculated at each pixel by exponential fitting. For 40 subjects (2 cohorts), two acquisition protocols were compared: (1) a breath-held, segmented acquisition, and (2) a free-breathing, single-shot multiple repetition respiratory motion corrected average. T2* measurements in the interventricular septum and liver were compared for the 2-methods in all studies with diagnostic image quality. RESULTS In cohort 1 (N = 28) with age 51.4 ± 17.6 (m ± SD) including 1 subject with severe myocardial iron overload, there were 8 non-diagnostic breath-held studies due to poor image quality resulting from ghost artifacts caused by respiratory motion or arrhythmias. In cohort 2 (N = 12) with age 30.9 ± 7.5 (m ± SD), including 7 subjects with severe myocardial iron overload and 4 subjects with mild iron overload, a single subject was unable to breath-hold. Free-breathing motion corrected T2* maps were of diagnostic quality in all 40 subjects. T2* measurements were in excellent agreement (In cohort #1, T2*FB = 0.95 x T2*BH + 0.41, r2 = 0.93, N = 39 measurements, and in cohort #2, T2*FB = 0.98 x T2*BH + 0.05, r2 > 0.99, N = 22 measurements). CONCLUSIONS A free-breathing approach to T2* mapping is demonstrated to produce consistently good quality maps in the presence of respiratory motion and arrhythmias.
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Affiliation(s)
- Peter Kellman
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | - Hui Xue
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | | | - Christopher M Sandino
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | - Michael S Hansen
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | - Amna Abdel-Gadir
- />The Heart Hospital, 16-18 Westmoreland Street, London, W1G 8PH UK
| | - Thomas A Treibel
- />The Heart Hospital, 16-18 Westmoreland Street, London, W1G 8PH UK
| | - Stefania Rosmini
- />The Heart Hospital, 16-18 Westmoreland Street, London, W1G 8PH UK
| | - Christine Mancini
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | - W Patricia Bandettini
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
| | - Laura-Ann McGill
- />Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP UK
| | - Peter Gatehouse
- />Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP UK
| | - James C Moon
- />The Heart Hospital, 16-18 Westmoreland Street, London, W1G 8PH UK
| | - Dudley J Pennell
- />Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, Sydney Street, London, SW3 6NP UK
| | - Andrew E Arai
- />National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 10 Center Drive MSC-1061, Bethesda, MD 20892 USA
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Ferreira PF, Kilner PJ, McGill LA, Nielles-Vallespin S, Scott AD, Ho SY, McCarthy KP, Haba MM, Ismail TF, Gatehouse PD, de Silva R, Lyon AR, Prasad SK, Firmin DN, Pennell DJ. In vivo cardiovascular magnetic resonance diffusion tensor imaging shows evidence of abnormal myocardial laminar orientations and mobility in hypertrophic cardiomyopathy. J Cardiovasc Magn Reson 2014; 16:87. [PMID: 25388867 PMCID: PMC4229618 DOI: 10.1186/s12968-014-0087-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 09/24/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Cardiac diffusion tensor imaging (cDTI) measures the magnitudes and directions of intramyocardial water diffusion. Assuming the cross-myocyte components to be constrained by the laminar microstructures of myocardium, we hypothesized that cDTI at two cardiac phases might identify any abnormalities of laminar orientation and mobility in hypertrophic cardiomyopathy (HCM). METHODS We performed cDTI in vivo at 3 Tesla at end-systole and late diastole in 11 healthy controls and 11 patients with HCM, as well as late gadolinium enhancement (LGE) for detection of regional fibrosis. RESULTS Voxel-wise analysis of diffusion tensors relative to left ventricular coordinates showed expected transmural changes of myocardial helix-angle, with no significant differences between phases or between HCM and control groups. In controls, the angle of the second eigenvector of diffusion (E2A) relative to the local wall tangent plane was larger in systole than diastole, in accord with previously reported changes of laminar orientation. HCM hearts showed higher than normal global E2A in systole (63.9° vs 56.4° controls, p=0.026) and markedly raised E2A in diastole (46.8° vs 24.0° controls, p<0.001). In hypertrophic regions, E2A retained a high, systole-like angulation even in diastole, independent of LGE, while regions of normal wall thickness did not (LGE present 57.8°, p=0.0028, LGE absent 54.8°, p=0.0022 vs normal thickness 38.1°). CONCLUSIONS In healthy controls, the angles of cross-myocyte components of diffusion were consistent with previously reported transmural orientations of laminar microstructures and their changes with contraction. In HCM, especially in hypertrophic regions, they were consistent with hypercontraction in systole and failure of relaxation in diastole. Further investigation of this finding is required as previously postulated effects of strain might be a confounding factor.
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Affiliation(s)
- Pedro F Ferreira
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Philip J Kilner
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Laura-Ann McGill
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Sonia Nielles-Vallespin
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
- />National Institutes of Health, Bethesda, USA
| | - Andrew D Scott
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Siew Y Ho
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Karen P McCarthy
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Margarita M Haba
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Tevfik F Ismail
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Peter D Gatehouse
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Ranil de Silva
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Alexander R Lyon
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Sanjay K Prasad
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - David N Firmin
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
| | - Dudley J Pennell
- />National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK
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14
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Scott AD, Ferreira PFADC, Nielles-Vallespin S, Gatehouse P, McGill LA, Kilner P, Pennell DJ, Firmin DN. Optimal diffusion weighting for in vivo cardiac diffusion tensor imaging. Magn Reson Med 2014; 74:420-30. [PMID: 25154715 DOI: 10.1002/mrm.25418] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 07/21/2014] [Accepted: 07/29/2014] [Indexed: 01/10/2023]
Abstract
PURPOSE To investigate the influence of the diffusion weighting on in vivo cardiac diffusion tensor imaging (cDTI) and obtain optimal parameters. METHODS Ten subjects were scanned using stimulated echo acquisition mode echo planar imaging with six b-values, from 50 to 950 s·mm(-2) , plus b = 15 s·mm(-2) reference. The relationship between b-value and both signal loss and signal-to-noise ratio measures was investigated. Mean diffusivity, fractional anisotropy, and helical angle maps were calculated using all possible b-value pairs to investigate the effects of diffusion weighting on the main and reference data. RESULTS Signal decay at low b-values was dominated by processes with high apparent diffusion coefficients, most likely microvascular perfusion. This effect could be avoided by diffusion weighting of the reference images. Parameter maps were improved with increased b-value until the diffusion-weighted signal approached the noise floor. For the protocol used in this study, b = 750 s·mm(-2) combined with 150 s·mm(-2) diffusion weighting of the reference images proved optimal. CONCLUSION Mean diffusivity, fractional anisotropy, and helical angle from cDTI are influenced by the b-value of the main and reference data. Using optimal values improves parameter maps and avoids microvascular perfusion effects. This optimized protocol should provide greater sensitivity to pathological changes in parameter maps.
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Affiliation(s)
- Andrew D Scott
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - Pedro F A D C Ferreira
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - Sonia Nielles-Vallespin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Peter Gatehouse
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - Laura-Ann McGill
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - Philip Kilner
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - Dudley J Pennell
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
| | - David N Firmin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College, London, UK
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15
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Tunnicliffe EM, Scott AD, Ferreira P, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin DN. Intercentre reproducibility of cardiac apparent diffusion coefficient and fractional anisotropy in healthy volunteers. J Cardiovasc Magn Reson 2014; 16:31. [PMID: 24886285 PMCID: PMC4028111 DOI: 10.1186/1532-429x-16-31] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 04/17/2014] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Diffusion tensor cardiac magnetic resonance (DT-CMR) enables probing of the microarchitecture of the myocardium, but the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) reported in healthy volunteers have been inconsistent. The aim of this study was to validate a stimulated-echo diffusion sequence using phantoms, and to assess the intercentre reproducibility of in-vivo diffusion measures using the sequence. METHODS AND RESULTS A stimulated-echo, cardiac-gated DT-CMR sequence with a reduced-field-of-view, single-shot EPI readout was used at two centres with 3 T MRI scanners. Four alkane phantoms with known diffusivities were scanned at a single centre using a stimulated echo sequence and a spin-echo Stejskal-Tanner diffusion sequence. The median (maximum, minimum) difference between the DT-CMR sequence and Stejskal-Tanner sequence was 0.01 (0.04, 0.0006) × 10(-3) mm2/s (2%), and between the DT-CMR sequence and literature diffusivities was 0.02 (0.05, 0.006) × 10(-3) mm2/s (4%).The same ten healthy volunteers were scanned using the DT-CMR sequence at the two centres less than seven days apart. Average ADC and FA were calculated in a single mid-ventricular, short axis slice. Intercentre differences were tested for statistical significance at the p < 0.05 level using paired t-tests. The mean ADC ± standard deviation for all subjects averaged over both centres was 1.10 ± 0.06 × 10(-3) mm2/s in systole and 1.20 ± 0.09 × 10-3 mm2/s in diastole; FA was 0.41 ± 0.04 in systole and 0.54 ± 0.03 in diastole. With similarly-drawn regions-of-interest, systolic ADC (difference 0.05 × 10(-3) mm2/s), systolic FA (difference 0.003) and diastolic FA (difference 0.01) were not statistically significantly different between centres (p > 0.05), and only the diastolic ADC showed a statistically significant, but numerically small, difference of 0.07 × 10(-3) mm2/s (p = 0.047). The intercentre, intrasubject coefficients of variance were: systolic ADC 7%, FA 6%; diastolic ADC 7%, FA 3%. CONCLUSIONS This is the first study to demonstrate the accuracy of a stimulated-echo DT-CMR sequence in phantoms, and demonstrates the feasibility of obtaining reproducible ADC and FA in healthy volunteers at separate centres with well-matched sequences and processing.
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Affiliation(s)
- Elizabeth M Tunnicliffe
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Andrew D Scott
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Pedro Ferreira
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Rina Ariga
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Laura-Ann McGill
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Sonia Nielles-Vallespin
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
- National Heart Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), DHHS, Bethesda, MD, USA
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Dudley J Pennell
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
| | - Matthew D Robson
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - David N Firmin
- NIHR Cardiovascular BRU, Royal Brompton Hospital & Imperial College, London, UK
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16
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McGill LA, Ferreira P, Scott AD, Nielles-Vallespin S, Ismail T, Silva R, Kilner PJ, Firmin D, Pennell DJ. Influence of subject characteristics on DTI parameters in the normal heart. J Cardiovasc Magn Reson 2014. [PMCID: PMC4044526 DOI: 10.1186/1532-429x-16-s1-p7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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17
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Ferreira P, Kilner PJ, McGill LA, Nielles-Vallespin S, Scott AD, Spottiswoode BS, Zhong X, Ho SY, McCarthy K, Ismail T, Gatehouse P, Silva R, Lyon A, Prasad SK, Firmin D, Pennell DJ. Aberrant myocardial sheetlet mobility in hypertrophic cardiomyopathy detected using in vivo cardiovascular magnetic resonance diffusion tensor imaging. J Cardiovasc Magn Reson 2014. [PMCID: PMC4044463 DOI: 10.1186/1532-429x-16-s1-p338] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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18
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McGill LA, Ferreira P, Scott AD, Nielles-Vallespin S, Silva R, Kilner PJ, Firmin D, Pennell DJ. Comparison of cardiac DTI parameters between systole and diastole. J Cardiovasc Magn Reson 2014. [PMCID: PMC4045133 DOI: 10.1186/1532-429x-16-s1-p39] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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19
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Scott AD, Ferreira P, Nielles-Vallespin S, McGill LA, Kilner PJ, Pennell DJ, Firmin D. Improved in-vivo cardiac DTI using optimal b-values. J Cardiovasc Magn Reson 2014. [PMCID: PMC4044394 DOI: 10.1186/1532-429x-16-s1-o27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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20
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Tunnicliffe EM, Scott AD, Ferreira P, Ariga R, McGill LA, Nielles-Vallespin S, Neubauer S, Pennell DJ, Robson MD, Firmin D. Inter-centre reproducibility of cardiac diffusion tensor measures. J Cardiovasc Magn Reson 2014. [PMCID: PMC4044755 DOI: 10.1186/1532-429x-16-s1-o84] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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21
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McGill LA, Ismail T, Nielles-Vallespin S, Ferreira P, Scott AD, Roughton M, Kilner PJ, Ho SY, McCarthy KP, Gatehouse PD, de Silva R, Speier P, Feiweier T, Mekkaoui C, Sosnovik DE, Prasad SK, Firmin DN, Pennell DJ. Erratum to: reproducibility of in-vivo diffusion tensor cardiovascular magnetic resonance in hypertrophic cardiomyopathy. J Cardiovasc Magn Reson 2013. [PMCID: PMC3627612 DOI: 10.1186/1532-429x-15-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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22
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McGill LA, Pennell DJ. Emerging roles for cardiovascular magnetic resonance. Clin Med (Lond) 2013; 13 Suppl 6:s3-8. [PMID: 24298179 DOI: 10.7861/clinmedicine.13-6-s3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Cardiovascular magnetic resonance (CMR) is a noninvasive imaging tool with high spatial resolution in the absence of ionising radiation. CMR imaging is routine in the functional assessment of coronary lesions and is widely held as the gold standard in myocardial viability imaging. Its unique tissue characterisation capabilities have revolutionised the assessment of the cardiomyopathies and it is the investigation of choice for cardiovascular surveillance imaging. To date its greatest success has been in the management of thalassaemia major, where the ability to detect myocardial iron loading has significantly improved patient survival. In the near future, CMR fibrosis imaging may serve as a risk stratification tool for the cardiomyopathies; and the ability to assess interstitial fibrosis may advance this role into other disease processes. Novel methods of tissue characterisation and emerging technical advances present new avenues for this modality, securing its place as the noninvasive imaging tool of the future.
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Affiliation(s)
- Laura-Ann McGill
- Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK
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23
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Jones DA, McGill LA, Rathod KS, Matthews K, Gallagher S, Uppal R, Mills PG, Das S, Yaqoob M, Ashman N, Wragg A. Characteristics and Outcomes of Dialysis Patients with Infective Endocarditis. ACTA ACUST UNITED AC 2013; 123:151-6. [DOI: 10.1159/000353732] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 06/10/2013] [Indexed: 11/19/2022]
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24
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McGill LA, Ismail TF, Nielles-Vallespin S, Ferreira P, Scott AD, Roughton M, Kilner PJ, Ho SY, McCarthy KP, Gatehouse PD, de Silva R, Speier P, Feiweier T, Mekkaoui C, Sosnovik DE, Prasad SK, Firmin DN, Pennell DJ. Reproducibility of in-vivo diffusion tensor cardiovascular magnetic resonance in hypertrophic cardiomyopathy. J Cardiovasc Magn Reson 2012; 14:86. [PMID: 23259835 PMCID: PMC3551746 DOI: 10.1186/1532-429x-14-86] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Myocardial disarray is an important histological feature of hypertrophic cardiomyopathy (HCM) which has been studied post-mortem, but its in-vivo prevalence and extent is unknown. Cardiac Diffusion Tensor Imaging (cDTI) provides information on mean intravoxel myocyte orientation and potentially myocardial disarray. Recent technical advances have improved in-vivo cDTI, and the aim of this study was to assess the interstudy reproducibility of quantitative in-vivo cDTI in patients with HCM. METHODS AND RESULTS A stimulated-echo single-shot-EPI sequence with zonal excitation and parallel imaging was implemented. Ten patients with HCM were each scanned on 2 different days. For each scan 3 short axis mid-ventricular slices were acquired with cDTI at end systole. Fractional anisotropy (FA), mean diffusivity (MD), and helix angle (HA) maps were created using a cDTI post-processing platform developed in-house. The mean ± SD global FA was 0.613 ± 0.044, MD was 0.750 ± 0.154 × 10-3 mm2/s and HA was epicardium -34.3 ± 7.6°, mesocardium 3.5 ± 6.9° and endocardium 38.9 ± 8.1°. Comparison of initial and repeat studies showed global interstudy reproducibility for FA (SD = ± 0.045, Coefficient of Variation (CoV) = 7.2%), MD (SD = ± 0.135 × 10-3 mm2/s, CoV = 18.6%) and HA (epicardium SD = ± 4.8°; mesocardium SD = ± 3.4°; endocardium SD = ± 2.9°). Reproducibility of FA was superior to MD (p = 0.003). MD was significantly higher in the septum than the reference lateral wall (0.784 ±0.188 vs 0.714 ±0.155 ×10-3 mm2/s, p <0.001) [corrected]. Septal HA was significantly lower than the reference lateral wall in all 3 transmural layers (from -8.3° to -10.4°, all p < 0.001). CONCLUSIONS To the best of our knowledge, this is the first study to assess the interstudy reproducibility of DTI in the human HCM heart in-vivo and the largest cDTI study in HCM to date. Our results show good reproducibility of FA, MD and HA which indicates that current technology yields robust in-vivo measurements that have potential clinical value. The interpretation of regional differences in the septum requires further investigation.
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Affiliation(s)
- Laura-Ann McGill
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Tevfik F Ismail
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
| | - Sonia Nielles-Vallespin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
- National Heart Lung and Blood Institute (NHLBI), National Institutes of Health (NIH), DHHS, Bethesda, MD, USA
| | - Pedro Ferreira
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Andrew D Scott
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Michael Roughton
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
| | - Philip J Kilner
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - S Yen Ho
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Karen P McCarthy
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Peter D Gatehouse
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
| | - Ranil de Silva
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Peter Speier
- MR R&D, Siemens AG Medical Solutions, Erlangen, Germany
| | | | - Choukkri Mekkaoui
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - David E Sosnovik
- Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Sanjay K Prasad
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - David N Firmin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
| | - Dudley J Pennell
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, United Kingdom
- National Heart and Lung Institute, Imperial College, London, UK
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Jones DA, Matthews K, McGill LA, Rathod K, Yaqoob M, Ashman N, Mills P, Wragg A. 095 Dialysis patients with infective endocarditis who received valve replacement have improved 1-year survival. Heart 2010. [DOI: 10.1136/hrt.2010.196071.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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