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Cabanis P, Magat J, Rodriguez-Padilla J, Ramlugun G, Yon M, Bihan-Poudec Y, Pallares-Lupon N, Vaillant F, Pasdois P, Jais P, Dos-Santos P, Constantin M, Benoist D, Pourtau L, Dubes V, Rogier J, Labrousse L, Haissaguerre M, Bernus O, Quesson B, Walton R, Duchateau J, Vigmond E, Ozenne V. Cardiac structure discontinuities revealed by ex-vivo microstructural characterization. A focus on the basal inferoseptal left ventricle region. J Cardiovasc Magn Reson 2023; 25:78. [PMID: 38093273 PMCID: PMC10720182 DOI: 10.1186/s12968-023-00989-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 11/15/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND While the microstructure of the left ventricle (LV) has been largely described, only a few studies investigated the right ventricular insertion point (RVIP). It was accepted that the aggregate cardiomyocytes organization was much more complex due to the intersection of the ventricular cavities but a precise structural characterization in the human heart was lacking even if clinical phenotypes related to right ventricular wall stress or arrhythmia were observed in this region. METHODS MRI-derived anatomical imaging (150 µm3) and diffusion tensor imaging (600 µm3) were performed in large mammalian whole hearts (human: N = 5, sheep: N = 5). Fractional anisotropy, aggregate cardiomyocytes orientations and tractography were compared within both species. Aggregate cardiomyocytes orientation on one ex-vivo sheep whole heart was then computed using structure tensor imaging (STI) from 21 µm isotropic acquisition acquired with micro computed tomography (MicroCT) imaging. Macroscopic and histological examination were performed. Lastly, experimental cardiomyocytes orientation distribution was then compared to the usual rule-based model using electrophysiological (EP) modeling. Electrical activity was modeled with the monodomain formulation. RESULTS The RVIP at the level of the inferior ventricular septum presented a unique arrangement of aggregate cardiomyocytes. An abrupt, mid-myocardial change in cardiomyocytes orientation was observed, delimiting a triangle-shaped region, present in both sheep and human hearts. FA's histogram distribution (mean ± std: 0.29 ± 0.06) of the identified region as well as the main dimension (22.2 mm ± 5.6 mm) was found homogeneous across samples and species. Averaged volume is 0.34 cm3 ± 0.15 cm3. Both local activation time (LAT) and morphology of pseudo-ECGs were strongly impacted with delayed LAT and change in peak-to-peak amplitude in the simulated wedge model. CONCLUSION The study was the first to describe the 3D cardiomyocytes architecture of the basal inferoseptal left ventricle region in human hearts and identify the presence of a well-organized aggregate cardiomyocytes arrangement and cardiac structural discontinuities. The results might offer a better appreciation of clinical phenotypes like RVIP-late gadolinium enhancement or uncommon idiopathic ventricular arrhythmias (VA) originating from this region.
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Affiliation(s)
- Pierre Cabanis
- Univ. Bordeaux, CNRS, CRMSB, UMR 5536, Bordeaux, France.
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.
- Centre de Résonance Magnétique des Systèmes Biologiques, 2 Rue Dr Hoffmann Martinot, 33000, Bordeaux, France.
| | - Julie Magat
- Univ. Bordeaux, CNRS, CRMSB, UMR 5536, Bordeaux, France
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Centre de Résonance Magnétique des Systèmes Biologiques, 2 Rue Dr Hoffmann Martinot, 33000, Bordeaux, France
| | | | - Girish Ramlugun
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Maxime Yon
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Yann Bihan-Poudec
- Centre de Neuroscience Cognitive, CNRS, Université Claude Bernard Lyon I, Villeurbanne, France
| | - Nestor Pallares-Lupon
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Fanny Vaillant
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Philippe Pasdois
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Pierre Jais
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Pierre Dos-Santos
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Marion Constantin
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - David Benoist
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Line Pourtau
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Virginie Dubes
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Julien Rogier
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Louis Labrousse
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Michel Haissaguerre
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Olivier Bernus
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Bruno Quesson
- Univ. Bordeaux, CNRS, CRMSB, UMR 5536, Bordeaux, France
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Centre de Résonance Magnétique des Systèmes Biologiques, 2 Rue Dr Hoffmann Martinot, 33000, Bordeaux, France
| | - Richard Walton
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
| | - Josselin Duchateau
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Cardiology Department, Bordeaux University Hospital (CHU), Pessac, France
| | - Edward Vigmond
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- CNRS, IMB, UMR5251, Talence, France
| | - Valéry Ozenne
- Univ. Bordeaux, CNRS, CRMSB, UMR 5536, Bordeaux, France
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France
- Centre de Résonance Magnétique des Systèmes Biologiques, 2 Rue Dr Hoffmann Martinot, 33000, Bordeaux, France
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2
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Bengel FM, Diekmann J, Hess A, Jerosch-Herold M. Myocardial Fibrosis: Emerging Target for Cardiac Molecular Imaging and Opportunity for Image-Guided Therapy. J Nucl Med 2023; 64:49S-58S. [PMID: 37918842 DOI: 10.2967/jnumed.122.264867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/25/2023] [Indexed: 11/04/2023] Open
Abstract
Myocardial fibrosis is a major contributor to the development and progression of heart failure. Significant progress in the understanding of its pathobiology has led to the introduction and preclinical testing of multiple highly specific antifibrotic therapies. Because the mechanisms of fibrosis are highly dynamic, and because the involved cell populations are heterogeneous and plastic, there is increasing emphasis that any therapy directed specifically against myocardial fibrosis will require personalization and guidance by equally specific diagnostic testing for successful clinical translation. Noninvasive imaging techniques have undergone significant progress and provide increasingly specific information about the quantity, quality, and activity of myocardial fibrosis. Cardiac MRI can precisely map the extracellular space of the myocardium, whereas nuclear imaging characterizes activated fibroblasts and immune cells as the cellular components contributing to fibrosis. Existing techniques may be used in complementarity to provide the imaging biomarkers needed for the success of novel targeted therapies. This review provides a road map on how progress in basic fibrosis research, antifibrotic drug development, and high-end noninvasive imaging may come together to facilitate the success of fibrosis-directed cardiovascular medicine.
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Affiliation(s)
- Frank M Bengel
- Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany; and
| | - Johanna Diekmann
- Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany; and
| | - Annika Hess
- Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany; and
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Pathophysiology of LV Remodeling Following STEMI: A Longitudinal Diffusion Tensor CMR Study. JACC Cardiovasc Imaging 2023; 16:159-171. [PMID: 36412993 PMCID: PMC9902278 DOI: 10.1016/j.jcmg.2022.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 02/28/2022] [Accepted: 04/07/2022] [Indexed: 11/20/2022]
Abstract
BACKGROUND Adverse LV remodeling post-ST-segment elevation myocardial infarction (STEMI) is associated with a poor prognosis, but the underlying mechanisms are not fully understood. Diffusion tensor (DT)-cardiac magnetic resonance (CMR) allows in vivo characterization of myocardial architecture and provides unique mechanistic insight into pathophysiologic changes following myocardial infarction. OBJECTIVES This study evaluated the potential associations between DT-CMR performed soon after STEMI and long-term adverse left ventricular (LV) remodeling following STEMI. METHODS A total of 100 patients with STEMI underwent CMR at 5 days and 12 months post-reperfusion. The protocol included DT-CMR for assessing fractional anisotropy (FA), secondary eigenvector angle (E2A) and helix angle (HA), cine imaging for assessing LV volumes, and late gadolinium enhancement for calculating infarct and microvascular obstruction size. Adverse remodeling was defined as a 20% increase in LV end-diastolic volume at 12 months. RESULTS A total of 32 patients experienced adverse remodeling at 12 months. Compared with patients without adverse remodeling, they had lower FA (0.23 ± 0.03 vs 0.27 ± 0.04; P < 0.001), lower E2A (37 ± 6° vs 51 ± 7°; P < 0.001), and, on HA maps, a lower proportion of myocytes with right-handed orientation (RHM) (8% ± 5% vs 17% ± 9%; P < 0.001) in their acutely infarcted myocardium. On multivariable logistic regression analysis, infarct FA (odds ratio [OR]: <0.01; P = 0.014) and E2A (OR: 0.77; P = 0.001) were independent predictors of adverse LV remodeling after adjusting for left ventricular ejection fraction (LVEF) and infarct size. There were no significant changes in infarct FA, E2A, or RHM between the 2 scans. CONCLUSIONS Extensive cardiomyocyte disorganization (evidenced by low FA), acute loss of sheetlet angularity (evidenced by low E2A), and a greater loss of organization among cardiomyocytes with RHM, corresponding to the subendocardium, can be detected within 5 days post-STEMI. These changes persist post-injury, and low FA and E2A are independently associated with long-term adverse remodeling.
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Li X, Chen R, Xu X, Xiao Z, Wei X, Yang Y, Zhang Z, Wu Z, Zhu Y, Liu H. The comparison of diffusion tensor imaging in human hearts between 1.5 T and 3.0 T. BMC Med Imaging 2023; 23:14. [PMID: 36698134 PMCID: PMC9875455 DOI: 10.1186/s12880-023-00969-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 01/16/2023] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The aim was to compare the diffusion tensor imaging (DTI) indices derived from human hearts between 1.5 T and 3.0 T scanners. Additionally, the reproducibility of DTI indices was assessed between 1.5 T and 3.0 T scanners. METHODS A total of 18 ex-vivo hearts were derived from patients who underwent heart transplantation. The DTI schemes were performed at 1.5 T and 3.0 T, respectively. Then, the same slices from each ex-vivo heart were selected for image analysis. The student's t-test or Wilcoxon-rank test was used to compare the statistical differences. The agreement of DTI indices was mainly reported as the interclass correlation coefficient (ICC). RESULTS No significant differences (all P > 0.05) were found in the DTI indices between 1.5 T and 3.0 T scanners. Interestingly, the ICC of all DTI indices was relatively lower with a low b-value. The reproducibility of the helix angle (HA) was relatively lower when compared to the other DTI indices. CONCLUSION The DTI indices of ex-vivo human hearts between 1.5 T and 3.0 T scanners had no significant differences. The consistency of DTI indices needed caution using a low b-value with different field strengths, and the relatively low reproducibility of HA should be considered.
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Affiliation(s)
- Xiaodan Li
- grid.284723.80000 0000 8877 7471Department of Radiology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China
| | - Rui Chen
- grid.284723.80000 0000 8877 7471Department of Radiology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China ,grid.79703.3a0000 0004 1764 3838School of Medicine, South China University of Technology, Guangzhou, Guangdong Province China
| | - Xi Xu
- grid.9227.e0000000119573309Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China ,grid.410726.60000 0004 1797 8419Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, China
| | - Zebin Xiao
- grid.284723.80000 0000 8877 7471Department of Pathology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China
| | - Xiaoyu Wei
- grid.284723.80000 0000 8877 7471Department of Radiology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China ,grid.79703.3a0000 0004 1764 3838School of Medicine, South China University of Technology, Guangzhou, Guangdong Province China
| | - Yuelong Yang
- grid.284723.80000 0000 8877 7471Department of Radiology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China
| | | | - Zhigang Wu
- Philips Healthcare China, Guangzhou, China
| | - Yanjie Zhu
- grid.9227.e0000000119573309Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China ,grid.410726.60000 0004 1797 8419Shenzhen College of Advanced Technology, University of Chinese Academy of Sciences, Shenzhen, China
| | - Hui Liu
- grid.284723.80000 0000 8877 7471Department of Radiology, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong Province China ,grid.79703.3a0000 0004 1764 3838School of Medicine, South China University of Technology, Guangzhou, Guangdong Province China ,grid.284723.80000 0000 8877 7471Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application, Guangdong Provincial People’s Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
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Teh I, Romero R. WA, Boyle J, Coll‐Font J, Dall'Armellina E, Ennis DB, Ferreira PF, Kalra P, Kolipaka A, Kozerke S, Lohr D, Mongeon F, Moulin K, Nguyen C, Nielles‐Vallespin S, Raterman B, Schreiber LM, Scott AD, Sosnovik DE, Stoeck CT, Tous C, Tunnicliffe EM, Weng AM, Croisille P, Viallon M, Schneider JE. Validation of cardiac diffusion tensor imaging sequences: A multicentre test-retest phantom study. NMR IN BIOMEDICINE 2022; 35:e4685. [PMID: 34967060 PMCID: PMC9285553 DOI: 10.1002/nbm.4685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 11/19/2021] [Accepted: 12/24/2021] [Indexed: 05/23/2023]
Abstract
Cardiac diffusion tensor imaging (DTI) is an emerging technique for the in vivo characterisation of myocardial microstructure, and there is a growing need for its validation and standardisation. We sought to establish the accuracy, precision, repeatability and reproducibility of state-of-the-art pulse sequences for cardiac DTI among 10 centres internationally. Phantoms comprising 0%-20% polyvinylpyrrolidone (PVP) were scanned with DTI using a product pulsed gradient spin echo (PGSE; N = 10 sites) sequence, and a custom motion-compensated spin echo (SE; N = 5) or stimulated echo acquisition mode (STEAM; N = 5) sequence suitable for cardiac DTI in vivo. A second identical scan was performed 1-9 days later, and the data were analysed centrally. The average mean diffusivities (MDs) in 0% PVP were (1.124, 1.130, 1.113) x 10-3 mm2 /s for PGSE, SE and STEAM, respectively, and accurate to within 1.5% of reference data from the literature. The coefficients of variation in MDs across sites were 2.6%, 3.1% and 2.1% for PGSE, SE and STEAM, respectively, and were similar to previous studies using only PGSE. Reproducibility in MD was excellent, with mean differences in PGSE, SE and STEAM of (0.3 ± 2.3, 0.24 ± 0.95, 0.52 ± 0.58) x 10-5 mm2 /s (mean ± 1.96 SD). We show that custom sequences for cardiac DTI provide accurate, precise, repeatable and reproducible measurements. Further work in anisotropic and/or deforming phantoms is warranted.
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Affiliation(s)
- Irvin Teh
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - William A. Romero R.
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Jordan Boyle
- School of Mechanical EngineeringUniversity of LeedsLeedsUK
| | - Jaume Coll‐Font
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Erica Dall'Armellina
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Daniel B. Ennis
- Division of RadiologyVA Palo Alto Health Care SystemPalo AltoCaliforniaUSA
- Department of RadiologyStanford UniversityStanfordCaliforniaUSA
| | - Pedro F. Ferreira
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - Prateek Kalra
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Arunark Kolipaka
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Sebastian Kozerke
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - David Lohr
- Department of Cardiovascular ImagingComprehensive Heart Failure CenterWürzburgGermany
| | | | - Kévin Moulin
- Department of RadiologyStanford UniversityStanfordCaliforniaUSA
| | - Christopher Nguyen
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Sonia Nielles‐Vallespin
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - Brian Raterman
- Department of RadiologyThe Ohio State University Wexner Medical CenterColumbusOhioUSA
| | - Laura M. Schreiber
- Department of Cardiovascular ImagingComprehensive Heart Failure CenterWürzburgGermany
| | - Andrew D. Scott
- Cardiovascular Magnetic Resonance UnitThe Royal Brompton and Harefield NHS Foundation TrustLondonUK
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - David E. Sosnovik
- Cardiovascular Research Center and A. A. Martinos Center for Biomedical ImagingMassachusetts General Hospital and Harvard Medical SchoolBostonMassachusettsUSA
| | - Christian T. Stoeck
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - Cyril Tous
- Department of Radiology, Radiation‐Oncology and Nuclear Medicine and Institute of Biomedical EngineeringUniversité de MontréalMontréalCanada
| | - Elizabeth M. Tunnicliffe
- Radcliffe Department of MedicineUniversity of OxfordOxfordUK
- Oxford NIHR Biomedical Research CentreOxfordUK
| | - Andreas M. Weng
- Department of Diagnostic and Interventional RadiologyUniversity Hospital WürzburgWürzburgGermany
| | - Pierre Croisille
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Magalie Viallon
- Univ Lyon, INSA‐Lyon, Université Claude Bernard Lyon 1UJM‐Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1294, F‐42023Saint EtienneFrance
| | - Jürgen E. Schneider
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
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From dissection of fibrotic pathways to assessment of drug interactions to reduce cardiac fibrosis and heart failure. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2021; 2:100036. [PMID: 34909666 PMCID: PMC8663973 DOI: 10.1016/j.crphar.2021.100036] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/14/2021] [Accepted: 05/18/2021] [Indexed: 12/14/2022] Open
Abstract
Cardiac fibrosis is characterized by extracellular matrix deposition in the cardiac interstitium, and this contributes to cardiac contractile dysfunction and progression of heart failure. The main players involved in this process are the cardiac fibroblasts, which, in the presence of pro-inflammatory/pro-fibrotic stimuli, undergo a complete transformation acquiring a more proliferative, a pro-inflammatory and a secretory phenotype. This review discusses the cellular effectors and molecular pathways implicated in the pathogenesis of cardiac fibrosis and suggests potential strategies to monitor the effects of specific drugs designed to slow down the progression of this disease by specifically targeting the fibroblasts.
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7
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Das A, Kelly C, Teh I, Nguyen C, Brown LAE, Chowdhary A, Jex N, Thirunavukarasu S, Sharrack N, Gorecka M, Swoboda PP, Greenwood JP, Kellman P, Moon JC, Davies RH, Lopes LR, Joy G, Plein S, Schneider JE, Dall'Armellina E. Phenotyping hypertrophic cardiomyopathy using cardiac diffusion magnetic resonance imaging: the relationship between microvascular dysfunction and microstructural changes. Eur Heart J Cardiovasc Imaging 2021; 23:352-362. [PMID: 34694365 PMCID: PMC8863073 DOI: 10.1093/ehjci/jeab210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 10/16/2021] [Indexed: 01/05/2023] Open
Abstract
Aims Microvascular dysfunction in hypertrophic cardiomyopathy (HCM) is predictive of clinical decline, however underlying mechanisms remain unclear. Cardiac diffusion tensor imaging (cDTI) allows in vivo characterization of myocardial microstructure by quantifying mean diffusivity (MD), fractional anisotropy (FA) of diffusion, and secondary eigenvector angle (E2A). In this cardiac magnetic resonance (CMR) study, we examine associations between perfusion and cDTI parameters to understand the sequence of pathophysiology and the interrelation between vascular function and underlying microstructure. Methods and results Twenty HCM patients underwent 3.0T CMR which included: spin-echo cDTI, adenosine stress and rest perfusion mapping, cine-imaging, and late gadolinium enhancement (LGE). Ten controls underwent cDTI. Myocardial perfusion reserve (MPR), MD, FA, E2A, and wall thickness were calculated per segment and further divided into subendocardial (inner 50%) and subepicardial (outer 50%) regions. Segments with wall thickness ≤11 mm, MPR ≥2.2, and no visual LGE were classified as ‘normal’. Compared to controls, ‘normal’ HCM segments had increased MD (1.61 ± 0.09 vs. 1.46 ± 0.07 × 10−3 mm2/s, P = 0.02), increased E2A (60 ± 9° vs. 38 ± 12°, P < 0.001), and decreased FA (0.29 ± 0.04 vs. 0.35 ± 0.02, P = 0.002). Across all HCM segments, subendocardial regions had higher MD and lower MPR than subepicardial (MDendo 1.61 ± 0.08 × 10−3 mm2/s vs. MDepi 1.56 ± 0.18 × 10−3 mm2/s, P = 0.003, MPRendo 1.85 ± 0.83, MPRepi 2.28 ± 0.87, P < 0.0001). Conclusion In HCM patients, even in segments with normal wall thickness, normal perfusion, and no scar, diffusion is more isotropic than in controls, suggesting the presence of underlying cardiomyocyte disarray. Increased E2A suggests the myocardial sheetlets adopt hypercontracted angulation in systole. Increased MD, most notably in the subendocardium, is suggestive of regional remodelling which may explain the reduced subendocardial blood flow.
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Affiliation(s)
- Arka Das
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Christopher Kelly
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Irvin Teh
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Christopher Nguyen
- Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, 55 Fruit St, Boston, MA 02114, USA.,A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, 55 Fruit St, Boston, MA 02114, USA.,Department of Medicine, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA.,Biomedical Imaging Research Institute, Cedars-Sinai Medical Centre, 116 N Robertson Blvd, Los Angeles, CA 90048, USA
| | - Louise A E Brown
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Amrit Chowdhary
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Nicholas Jex
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Sharmaine Thirunavukarasu
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Noor Sharrack
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Miroslawa Gorecka
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Peter P Swoboda
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - John P Greenwood
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Peter Kellman
- National Heart, Lung, and Blood Institute, National Institutes of Health, DHHS, 31 Center Dr, Bethesda, MD 20892, USA
| | - James C Moon
- Barts Heart Centre, The Cardiovascular Magnetic Resonance Imaging Unit and The Inherited Cardiovascular Diseases Unit, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
| | - Rhodri H Davies
- Barts Heart Centre, The Cardiovascular Magnetic Resonance Imaging Unit and The Inherited Cardiovascular Diseases Unit, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
| | - Luis R Lopes
- Barts Heart Centre, The Cardiovascular Magnetic Resonance Imaging Unit and The Inherited Cardiovascular Diseases Unit, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK.,Centre for Heart Muscle Disease, Institute of Cardiovascular Science, University College London, Gower St, London WC1E 6BT, UK
| | - George Joy
- Barts Heart Centre, The Cardiovascular Magnetic Resonance Imaging Unit and The Inherited Cardiovascular Diseases Unit, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
| | - Sven Plein
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Jürgen E Schneider
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
| | - Erica Dall'Armellina
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds Teaching Hospitals NHS Trust, Leeds LS2 9JT, UK
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8
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Das A, Kelly C, Teh I, Stoeck CT, Kozerke S, Chowdhary A, Brown LAE, Saunderson CED, Craven TP, Chew PG, Jex N, Swoboda PP, Levelt E, Greenwood JP, Schneider JE, Plein S, Dall'Armellina E. Acute Microstructural Changes after ST-Segment Elevation Myocardial Infarction Assessed with Diffusion Tensor Imaging. Radiology 2021; 299:86-96. [PMID: 33560187 DOI: 10.1148/radiol.2021203208] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Cardiac diffusion tensor imaging (cDTI) allows for in vivo characterization of myocardial microstructure. In cDTI, mean diffusivity and fractional anisotropy (FA)-markers of magnitude and anisotropy of diffusion of water molecules-are known to change after myocardial infarction. However, little is known about regional changes in helix angle (HA) and secondary eigenvector angle (E2A), which reflects orientations of laminar sheetlets, and their association with long-term recovery of left ventricular ejection fraction (LVEF). Purpose To assess serial changes in cDTI biomarkers in participants following ST-segment elevation myocardial infarction (STEMI) and to determine their associations with long-term left ventricular remodeling. Materials and Methods In this prospective study, 30 participants underwent cardiac MRI (3 T) after STEMI at 5 days and 3 months after reperfusion (National Institute of Health Research study no. 33963 and Research Ethics no. REC17/YH/0062). Spin-echo cDTI with second-order motion-compensation (approximate duration, 13 minutes; three sections; 18 noncollinear diffusion-weighted scans with b values of 100 sec/mm2 [three acquisitions], 200 sec/mm2 [three acquisitions], and 500 sec/mm2 [12 acquisitions]), functional images, and late gadolinium enhancement images were obtained. Multiple regression analysis was used to assess associations between acute cDTI parameters and 3-month LVEF. Results Acutely infarcted myocardium had reduced FA, E2A, and myocytes with right-handed orientation (RHM) on HA maps compared with remote myocardium (mean remote FA = 0.36 ± 0.02 [standard deviation], mean infarcted FA = 0.25 ± 0.03, P < .001; mean remote E2A = 55° ± 9, mean infarcted E2A = 49° ± 10, P < .001; mean remote RHM = 16% ± 6, mean infarcted RHM = 9% ± 5, P < .001). All three parameters (FA, E2A, and RHM) correlated with 3-month LVEF (r = 0.68, r = 0.59, and r = 0.53, respectively), with acute FA being independently predictive of 3-month LVEF (standardized β = 0.56, P = .008) after multivariable analysis adjusting for factors, including acute LVEF and infarct size. Conclusion After ST-segment elevation myocardial infarction, diffusion becomes more isotropic in acutely infarcted myocardium as reflected by decreased fractional anisotropy. Reductions in secondary eigenvector angle suggest that the myocardial sheetlets are unable to adopt their usual steep orientations in systole, whereas reductions in myocytes with right-handed orientation on helix angle maps are likely reflective of a loss of organization among subendocardial myocytes. Correlations between these parameters and 3-month left ventricular ejection fraction highlight the potential clinical use of cardiac diffusion tensor imaging after myocardial infarction in predicting long-term remodeling. © RSNA, 2021 Online supplemental material is available for this article.
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Affiliation(s)
- Arka Das
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Christopher Kelly
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Irvin Teh
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Christian T Stoeck
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Sebastian Kozerke
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Amrit Chowdhary
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Louise A E Brown
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Christopher E D Saunderson
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Thomas P Craven
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Pei G Chew
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Nicholas Jex
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Peter P Swoboda
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Eylem Levelt
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - John P Greenwood
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Jurgen E Schneider
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Sven Plein
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
| | - Erica Dall'Armellina
- From the Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, and Leeds Teaching Hospitals NHS Trust, Clarendon, Way, Leeds LS2 9JT, England (A.D., C.K., I.T., A.C., L.A.E.B., C.E.D.S., T.P.C., P.G.C., N.J., P.P.S., E.L., J.P.G., J.E.S., S.P., E.D.); and Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland (C.T.S., S.K.)
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9
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Das A, Chowdhary A, Kelly C, Teh I, Stoeck CT, Kozerke S, Maxwell N, Craven TP, Jex NJ, Saunderson CED, Brown LAE, Ben-Arzi H, Sengupta A, Page SP, Swoboda PP, Greenwood JP, Schneider JE, Plein S, Dall'Armellina E. Insight Into Myocardial Microstructure of Athletes and Hypertrophic Cardiomyopathy Patients Using Diffusion Tensor Imaging. J Magn Reson Imaging 2021; 53:73-82. [PMID: 32558016 DOI: 10.1002/jmri.27257] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Hypertrophic cardiomyopathy (HCM) remains the commonest cause of sudden cardiac death among young athletes. Differentiating between physiologically adaptive left ventricular (LV) hypertrophy observed in athletes' hearts and pathological HCM remains challenging. By quantifying the diffusion of water molecules, diffusion tensor imaging (DTI) MRI allows voxelwise characterization of myocardial microstructure. PURPOSE To explore microstructural differences between healthy volunteers, athletes, and HCM patients using DTI. STUDY TYPE Prospective cohort. POPULATION Twenty healthy volunteers, 20 athletes, and 20 HCM patients. FIELD STRENGTH/SEQUENCE 3T/DTI spin echo. ASSESSMENT In-house MatLab software was used to derive mean diffusivity (MD) and fractional anisotropy (FA) as markers of amplitude and anisotropy of the diffusion of water molecules, and secondary eigenvector angles (E2A)-reflecting the orientations of laminar sheetlets. STATISTICAL TESTS Independent samples t-tests were used to detect statistical significance between any two cohorts. Analysis of variance was utilized for detecting the statistical difference between the three cohorts. Statistical tests were two-tailed. A result was considered statistically significant at P ≤ 0.05. RESULTS DTI markers were significantly different between HCM, athletes, and volunteers. HCM patients had significantly higher global MD and E2A, and significantly lower FA than athletes and volunteers. (MDHCM = 1.52 ± 0.06 × 10-3 mm2 /s, MDAthletes = 1.49 ± 0.03 × 10-3 mm2 /s, MDvolunteers = 1.47 ± 0.02 × 10-3 mm2 /s, P < 0.05; E2AHCM = 58.8 ± 4°, E2Aathletes = 47 ± 5°, E2Avolunteers = 38.5 ± 7°, P < 0.05; FAHCM = 0.30 ± 0.02, FAAthletes = 0.35 ± 0.02, FAvolunteers = 0.36 ± 0.03, P < 0.05). HCM patients had significantly higher E2A in their thickest segments compared to the remote (E2Athickest = 66.8 ± 7, E2Aremote = 51.2 ± 9, P < 0.05). DATA CONCLUSION DTI depicts an increase in amplitude and isotropy of diffusion in the myocardium of HCM compared to athletes and volunteers as reflected by increased MD and decreased FA values. While significantly higher E2A values in HCM and athletes reflect steeper configurations of the myocardial sheetlets than in volunteers, HCM patients demonstrated an eccentric rise in E2A in their thickest segments, while athletes demonstrated a concentric rise. Further studies are required to determine the diagnostic capabilities of DTI. EVIDENCE LEVEL 1 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Arka Das
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Amrit Chowdhary
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Chris Kelly
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Irvin Teh
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Christian T Stoeck
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Nicholas Maxwell
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Thomas P Craven
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Nicholas J Jex
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Christopher E D Saunderson
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Louise A E Brown
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Hadar Ben-Arzi
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Anshuman Sengupta
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Stephen P Page
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Peter P Swoboda
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - John P Greenwood
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jurgen E Schneider
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Sven Plein
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Erica Dall'Armellina
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds Teaching Hospitals NHS Trust, Leeds, UK
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10
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Chen HH, Hu H, Chen W, Cui D, Xu XQ, Wu FY, Yang T. Thyroid-Associated Orbitopathy: Evaluating Microstructural Changes of Extraocular Muscles and Optic Nerves Using Readout-Segmented Echo-Planar Imaging-Based Diffusion Tensor Imaging. Korean J Radiol 2020; 21:332-340. [PMID: 32090526 PMCID: PMC7039723 DOI: 10.3348/kjr.2019.0053] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 11/07/2019] [Indexed: 01/13/2023] Open
Abstract
Objective We aimed to investigate the ability of readout-segmented echo-planar imaging (rs-EPI)-based diffusion tensor imaging (DTI) in assessing the microstructural change of extraocular muscles (EOMs) and optic nerves in patients with thyroid-associated orbitopathy (TAO) as well as in evaluating disease activity. Materials and Methods We enrolled 35 TAO patients and 22 healthy controls (HCs) who underwent pre-treatment rs-EPI-based DTI. Mean, axial, and radial diffusivity (MD, AD, and RD) and fractional anisotropy (FA) of the medial and lateral EOMs and optic nerve for each orbit were calculated and compared between TAO and HC groups and between active and inactive TAO groups. Factors such as age, sex, disease duration, mediation, and smoking history between groups were also compared. Logistic regression analysis was used to evaluate the predictive value of significant variables for disease activity. Results Disease duration was significantly shorter in active TAOs than in inactive ones (p < 0.001). TAO patients showed significantly lower FA and higher MD, AD, and RD than HCs for both medial and lateral EOMs (p < 0.001), but not the AD value of lateral EOMs (p = 0.619). Active patients had significantly higher FA, MD, and AD than inactive patients for medial EOMs (p < 0.005), whereas only FA differed significantly in the lateral EOMs (p = 0.018). The MD, AD, and RD of optic nerves were significantly lower in TAO patients than HCs (p < 0.05), except for FA (p = 0.129). Multivariate analysis showed that the MD of medial EOMs and disease duration were significant predictors for disease activity. The combination of these two parameters showed optimal diagnostic efficiency for disease activity (area under the curve, 0.855; sensitivity, 68.4%; specificity, 96.9%). Conclusion rs-EPI-based DTI is promising in assessing microstructural changes of EOMs and optic nerves and can help to indicate the disease activity of TAO, especially through the MD of medial EOMs.
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Affiliation(s)
- Huan Huan Chen
- Department of Endocrinology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hao Hu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Wen Chen
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Dai Cui
- Department of Endocrinology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiao Quan Xu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Fei Yun Wu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Tao Yang
- Department of Endocrinology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
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11
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Le B, Ferreira P, Merchant S, Zheng G, Sutherland MR, Dahl MJ, Albertine KH, Black MJ. Microarchitecture of the hearts in term and former-preterm lambs using diffusion tensor imaging. Anat Rec (Hoboken) 2020; 304:803-817. [PMID: 33015923 DOI: 10.1002/ar.24516] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/31/2020] [Accepted: 06/30/2020] [Indexed: 12/13/2022]
Abstract
Diffusion tensor imaging (DTI) is an MRI technique that can be used to map cardiomyocyte tracts and estimate local cardiomyocyte and sheetlet orientation within the heart. DTI measures diffusion distances of water molecules within the myocardium, where water diffusion generally occurs more freely along the long axis of cardiomyocytes and within the extracellular matrix, but is restricted by cell membranes such that transverse diffusion is limited. DTI can be undertaken in fixed hearts and it allows the three-dimensional mapping of the cardiac microarchitecture, including cardiomyocyte organization, within the whole heart. The objective of this study was to use DTI to compare the cardiac microarchitecture and cardiomyocyte organization in archived fixed left ventricles of lambs that were born either preterm (n = 5) or at term (n = 7), at a postnatal timepoint equivalent to about 6 years of age in children. Although the findings support the feasibility of retrospective DTI scanning of fixed hearts, several hearts were excluded from DTI analysis because of poor scan quality, such as ghosting artifacts. The preliminary findings from viable DTI scans (n = 3/group) suggest that the extracellular compartment is altered and that there is an immature microstructural phenotype early in postnatal life in the LV of lambs born preterm. Our findings support a potential time-efficient imaging role for DTI in detecting abnormal changes in the microstructure of fixed hearts of former-preterm neonates, although further investigation into factors that affect scan quality is required.
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Affiliation(s)
- Bianca Le
- Department of Anatomy and Developmental Biology and Biomedicine Discovery Institute, Monash University, Victoria, Australia
| | | | - Samer Merchant
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA
| | - Gang Zheng
- Monash Biomedical Imaging, Monash University, Victoria, Australia
| | - Megan R Sutherland
- Department of Anatomy and Developmental Biology and Biomedicine Discovery Institute, Monash University, Victoria, Australia
| | - Mar Janna Dahl
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA
| | - Kurt H Albertine
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA
| | - Mary Jane Black
- Department of Anatomy and Developmental Biology and Biomedicine Discovery Institute, Monash University, Victoria, Australia
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12
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Wu R, An DA, Shi RY, Chen BH, Wu CW, Jiang M, Xu JR, Wu LM, Pu J. The feasibility and diagnostic value of intravoxel incoherent motion diffusion-weighted imaging in the assessment of myocardial fibrosis in hypertrophic cardiomyopathy patients. Eur J Radiol 2020; 132:109333. [PMID: 33068839 DOI: 10.1016/j.ejrad.2020.109333] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 02/27/2020] [Accepted: 09/30/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To investigate the feasibility and diagnostic value of intravoxel incoherent motion (IVIM) in the assessment of myocardial fibrosis in hypertrophic cardiomyopathy (HCM) patients. METHODS Fifty-five HCM patients underwent IVIM diffusion-weighted cardiovascular resonance imaging; Cine, T1 mapping, IVIM and late gadolinium enhancement (LGE) were performed. The relationship of strain, pre T1, extracellular volume (ECV), IVIM-derived parameters (D, D* and f) and LGE were analyzed based on 16 American Heart Association segments. Abnormal segments of myocardial fibrosis were defined as: the presence of LGE (LGE+) or ECV ≥ 29.6 %. RESULTS D parameter was significantly increased in LGE + vs LGE- (1.89 ± 0.14 μm2/ms vs. 1.63 ± 0.12 μm2/ms, p < 0.001) and ECV ≥ 29.6 % vs ECV < 29.6 % (1.84 ± 0.13 μm2/ms vs. 1.61 ± 0.12 μm2/ms, p < 0.001), respectively. D* and f parameters were significantly decreased in LGE + vs LGE- (D*: 34.9 ± 6.6 μm2/m vs 55.2 ± 11.4 μm2/m, p < 0.001; f: 10.8 ± 1.29 % vs 12.5 ± 1.26 %, p < 0.001) and ECV ≥ 29.6 % vs ECV < 29.6 % (D*: 37.5 ± 6.9 μm2/m vs 59.6 ± 9.2 μm2/m, p < 0.001; f: 10.9 ± 1.1 % vs 13.00 ± 1.0 %, p = 0.021), respectively. Moreover, significant correlations were demonstrated between D and ECV, as well as D* and f. CONCLUSIONS IVIM DW-CMR has proven to be ingenious in the investigation of myocardial fibrosis; D* and f parameters may have potential value to assess the perfusion status of fibrotic regions in HCM patients.
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Affiliation(s)
- Rui Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Dong-Aolei An
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Ruo-Yang Shi
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Bing-Hua Chen
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Chong-Wen Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Meng Jiang
- Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Jian-Rong Xu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China
| | - Lian-Ming Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China.
| | - Jun Pu
- Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No.160 PuJian Road Shanghai 200127, China.
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13
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Lohr D, Terekhov M, Veit F, Schreiber LM. Longitudinal assessment of tissue properties and cardiac diffusion metrics of the ex vivo porcine heart at 7 T: Impact of continuous tissue fixation using formalin. NMR IN BIOMEDICINE 2020; 33:e4298. [PMID: 32207190 DOI: 10.1002/nbm.4298] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/18/2020] [Accepted: 03/05/2020] [Indexed: 05/12/2023]
Abstract
In this study we aimed to assess the effects of continuous formalin fixation on diffusion and relaxation metrics of the ex vivo porcine heart at 7 T. Magnetic resonance imaging was performed on eight piglet hearts using a 7 T whole body system. Hearts were measured fresh within 3 hours of cardiac arrest followed by immersion in 10% neutral buffered formalin. T2* and T2 were assessed using a gradient multi-echo and multi-echo spin echo sequence, respectively. A spin echo and a custom stimulated echo sequence were employed to assess diffusion time-dependent changes in metrics of cardiac diffusion tensor imaging. SNR was determined for b = 0 images. Scans were performed for 5 mm thick apical, midcavity and basal slices (in-plane resolution: 1 mm) and repeated 7, 15, 50, 100 and 200 days postfixation. Eigenvalues of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) decreased significantly (P < 0.05) following fixation. Relative to fresh hearts, FA values 7 and 200 days postfixation were 90% and 80%, while respective relative ADC values at those fixation stages were 78% and 92%. Statistical helix and sheetlet angle distributions as well as respective mean and median values showed no systematic influence of continuous formalin fixation. Similar to changes in the ADC, values for T2 , T2* and SNR dropped initially postfixation. Respective relative values compared with fresh hearts at day 7 were 64%, 79% and 68%, whereas continuous fixation restored T2 , T2* and SNR leading to relative values of 74%, 100%, and 81% at day 200, respectively. Relaxation parameters and diffusion metrics are significantly altered by continuous formalin fixation. The preservation of microstructure metrics following prolonged fixation is a key finding that may enable future studies of ventricular remodeling in cardiac pathologies.
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Affiliation(s)
- David Lohr
- Cellular and Molecular Imaging, Comprehensive Heart Failure Center (CHFC), University Hospital Wuerzburg, Wuerzburg, Germany
| | - Maxim Terekhov
- Cellular and Molecular Imaging, Comprehensive Heart Failure Center (CHFC), University Hospital Wuerzburg, Wuerzburg, Germany
| | - Franziska Veit
- Tissue Engineering and Regenerative Medicine (TERM), University Hospital Wuerzburg, Wuerzburg, Germany
| | - Laura Maria Schreiber
- Cellular and Molecular Imaging, Comprehensive Heart Failure Center (CHFC), University Hospital Wuerzburg, Wuerzburg, Germany
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14
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Campanale CM, Scherrer B, Afacan O, Majeed A, Warfield SK, Sanders SP. Myofiber organization in the failing systemic right ventricle. J Cardiovasc Magn Reson 2020; 22:49. [PMID: 32600420 PMCID: PMC7322876 DOI: 10.1186/s12968-020-00637-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 05/13/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The right ventricle (RV) often fails when functioning as the systemic ventricle, but the cause is not understood. We tested the hypothesis that myofiber organization is abnormal in the failing systemic right ventricle. METHODS We used diffusion-weighted cardiovascular magnetic resonance imaging to examine 3 failing hearts explanted from young patients with a systemic RV and one structurally normal heart with postnatally acquired RV hypertrophy for comparison. Diffusion compartment imaging was computed to separate the free diffusive component representing free water from an anisotropic component characterizing the orientation and diffusion characteristics of myofibers. The orientation of each anisotropic compartment was displayed in glyph format and used for qualitative description of myofibers and for construction of tractograms. The helix angle was calculated across the ventricular walls in 5 locations and displayed graphically. Scalar parameters (fractional anisotropy and mean diffusivity) were compared among specimens. RESULTS The hypertrophied systemic RV has an inner layer, comprising about 2/3 of the wall, composed of hypertrophied trabeculae and an epicardial layer of circumferential myofibers. Myofibers within smaller trabeculae are aligned and organized with parallel fibers while larger, composite bundles show marked disarray, largely between component trabeculae. We observed a narrow range of helix angles in the outer, compact part of the wall consistent with aligned, approximately circumferential fibers. However, there was marked variation of helix angle in the inner, trabecular part of the wall consistent with marked variation in fiber orientation. The apical whorl was disrupted or incomplete and we observed myocardial whorls or vortices at other locations. Fractional anisotropy was lower in abnormal hearts while mean diffusivity was more variable, being higher in 2 but lower in 1 heart, compared to the structurally normal heart. CONCLUSIONS Myofiber organization is abnormal in the failing systemic RV and might be an important substrate for heart failure and arrhythmia. It is unclear if myofiber disorganization is due to hemodynamic factors, developmental problems, or both.
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MESH Headings
- Adolescent
- Child, Preschool
- Diffusion Magnetic Resonance Imaging
- Female
- Heart Defects, Congenital/diagnostic imaging
- Heart Defects, Congenital/pathology
- Heart Defects, Congenital/physiopathology
- Heart Defects, Congenital/surgery
- Heart Failure/diagnostic imaging
- Heart Failure/pathology
- Heart Failure/physiopathology
- Heart Failure/surgery
- Heart Transplantation
- Heart Ventricles/diagnostic imaging
- Heart Ventricles/pathology
- Heart Ventricles/physiopathology
- Heart Ventricles/surgery
- Humans
- Male
- Myocardium/pathology
- Myofibrils/pathology
- Predictive Value of Tests
- Ventricular Dysfunction, Right/diagnostic imaging
- Ventricular Dysfunction, Right/pathology
- Ventricular Dysfunction, Right/physiopathology
- Ventricular Dysfunction, Right/surgery
- Ventricular Function, Right
- Young Adult
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Affiliation(s)
- Cosimo M. Campanale
- Unit of Perinatal Cardiology, Department of Neonatology, Ospedale Pediatrico Bambino Gesù di Roma, Rome, Italy
| | - Benoit Scherrer
- Department of Radiology, Boston Children’s Hospital and Harvard Medical School, Boston, MA USA
| | - Onur Afacan
- Department of Radiology, Boston Children’s Hospital and Harvard Medical School, Boston, MA USA
| | - Amara Majeed
- Department of Cardiology, Boston Children’s Hospital and Department of Pediatrics, Harvard Medical School, Boston, MA USA
| | - Simon K. Warfield
- Department of Radiology, Boston Children’s Hospital and Harvard Medical School, Boston, MA USA
| | - Stephen P. Sanders
- Cardiac Registry, Departments of Cardiology, Pathology and Cardiac Surgery, Boston Children’s Hospital, 300 Longwood Ave, Boston, MA 02115, USA. and Department of Pediatrics, Harvard Medical School, Boston, MA USA
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15
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Carruth ED, Teh I, Schneider JE, McCulloch AD, Omens JH, Frank LR. Regional variations in ex-vivo diffusion tensor anisotropy are associated with cardiomyocyte remodeling in rats after left ventricular pressure overload. J Cardiovasc Magn Reson 2020; 22:21. [PMID: 32241289 PMCID: PMC7114814 DOI: 10.1186/s12968-020-00615-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 03/05/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Pressure overload left ventricular (LV) hypertrophy is characterized by increased cardiomyocyte width and ventricle wall thickness, however the regional variation of this remodeling is unclear. Cardiovascular magnetic resonance (CMR) diffusion tensor imaging (DTI) may provide a non-invasive, comprehensive, and geometrically accurate method to detect regional differences in structural remodeling in hypertrophy. We hypothesized that DTI parameters, such as fractional and planar anisotropy, would reflect myocyte remodeling due to pressure overload in a regionally-dependent manner. METHODS We investigated the regional distributions of myocyte remodeling in rats with or without transverse aortic constriction (TAC) via direct measurement of myocyte dimensions with confocal imaging of thick tissue sections, and correlated myocyte cross-sectional area and other geometric features with parameters of diffusivity from ex-vivo DTI in the same regions of the same hearts. RESULTS We observed regional differences in several parameters from DTI between TAC hearts and SHAM controls. Consistent with previous studies, helix angles from DTI correlated strongly with those measured directly from histological sections (p < 0.001, R2 = 0.71). There was a transmural gradient in myocyte cross-sectional area in SHAM hearts that was diminished in the TAC group. We also found several regions of significantly altered DTI parameters in TAC LV compared to SHAM, especially in myocyte sheet angle dispersion and planar anisotropy. Among others, these parameters correlated significantly with directly measured myocyte aspect ratios. CONCLUSIONS These results show that structural remodeling in pressure overload LV hypertrophy is regionally heterogeneous, especially transmurally, with a greater degree of remodeling in the sub-endocardium compared to the sub-epicardium. Additionally, several parameters derived from DTI correlated significantly with measurements of myocyte geometry from direct measurement in histological sections. We suggest that DTI may provide a non-invasive, comprehensive method to detect regional structural myocyte LV remodeling during disease.
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Affiliation(s)
- Eric D Carruth
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Irvin Teh
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
| | - Jurgen E Schneider
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
| | - Andrew D McCulloch
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Jeffrey H Omens
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA.
- Department of Medicine, University of California San Diego, La Jolla, California, USA.
| | - Lawrence R Frank
- Department of Radiology, University of California San Diego, La Jolla, California, USA
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16
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Ariga R, Tunnicliffe EM, Manohar SG, Mahmod M, Raman B, Piechnik SK, Francis JM, Robson MD, Neubauer S, Watkins H. Identification of Myocardial Disarray in Patients With Hypertrophic Cardiomyopathy and Ventricular Arrhythmias. J Am Coll Cardiol 2020; 73:2493-2502. [PMID: 31118142 PMCID: PMC6548973 DOI: 10.1016/j.jacc.2019.02.065] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 02/07/2019] [Accepted: 02/26/2019] [Indexed: 01/26/2023]
Abstract
Background Myocardial disarray is a likely focus for fatal arrhythmia in hypertrophic cardiomyopathy (HCM). This microstructural abnormality can be inferred by mapping the preferential diffusion of water along cardiac muscle fibers using diffusion tensor cardiac magnetic resonance (DT-CMR) imaging. Fractional anisotropy (FA) quantifies directionality of diffusion in 3 dimensions. The authors hypothesized that FA would be reduced in HCM due to disarray and fibrosis that may represent the anatomic substrate for ventricular arrhythmia. Objectives This study sought to assess FA as a noninvasive in vivo biomarker of HCM myoarchitecture and its association with ventricular arrhythmia. Methods A total of 50 HCM patients (47 ± 15 years of age, 77% male) and 30 healthy control subjects (46 ± 16 years of age, 70% male) underwent DT-CMR in diastole, cine, late gadolinium enhancement (LGE), and extracellular volume (ECV) imaging at 3-T. Results Diastolic FA was reduced in HCM compared with control subjects (0.49 ± 0.05 vs. 0.52 ± 0.03; p = 0.0005). Control subjects had a mid-wall ring of high FA. In HCM, this ring was disrupted by reduced FA, consistent with published histology demonstrating that disarray and fibrosis invade circumferentially aligned mid-wall myocytes. LGE and ECV were significant predictors of FA, in line with fibrosis contributing to low FA. Yet FA adjusted for LGE and ECV remained reduced in HCM (p = 0.028). FA in the hypertrophied segment was reduced in HCM patients with ventricular arrhythmia compared to patients without (n = 15; 0.41 ± 0.03 vs. 0.46 ± 0.06; p = 0.007). A decrease in FA of 0.05 increased odds of ventricular arrhythmia by 2.5 (95% confidence interval: 1.2 to 5.3; p = 0.015) in HCM and remained significant even after correcting for LGE, ECV, and wall thickness (p = 0.036). Conclusions DT-CMR assessment of left ventricular myoarchitecture matched patterns reported previously on histology. Low diastolic FA in HCM was associated with ventricular arrhythmia and is likely to represent disarray after accounting for fibrosis. The authors propose that diastolic FA could be the first in vivo marker of disarray in HCM and a potential independent risk factor.
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Affiliation(s)
- Rina Ariga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Elizabeth M Tunnicliffe
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sanjay G Manohar
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Betty Raman
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan K Piechnik
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jane M Francis
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matthew D Robson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Hugh Watkins
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.
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17
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Abstract
The role of right ventricular (RV) fibrosis in pulmonary hypertension (PH) remains a subject of ongoing discussion. Alterations of the collagen network of the extracellular matrix may help prevent ventricular dilatation in the pressure-overloaded RV. At the same time, fibrosis impairs cardiac function, and a growing body of experimental data suggests that fibrosis plays a crucial role in the development of RV failure. In idiopathic pulmonary arterial hypertension and chronic thromboembolic PH, the RV is exposed to a ≈5 times increased afterload, which makes these conditions excellent models for studying the impact of pressure overload on RV structure. With this review, we present clinical evidence of RV fibrosis in idiopathic pulmonary arterial hypertension and chronic thromboembolic PH, explore the correlation between fibrosis and RV function, and discuss the clinical relevance of RV fibrosis in patients with PH. We postulate that RV fibrosis has a dual role in patients with pressure-overloaded RVs of idiopathic pulmonary arterial hypertension and chronic thromboembolic PH: as part of an adaptive response to prevent cardiomyocyte overstretch and to maintain RV shape for optimal function, and as part of a maladaptive response that increases diastolic stiffness, perturbs cardiomyocyte excitation-contraction coupling, and disrupts the coordination of myocardial contraction. Finally, we discuss potential novel therapeutic strategies and describe more sensitive techniques to quantify RV fibrosis, which may be used to clarify the causal relation between RV fibrosis and RV function in future research.
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Affiliation(s)
| | | | | | - Frances S de Man
- Amsterdam UMC, Vrije Universiteit, The Netherlands (A.V.N., F.S.d.M)
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18
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Nielles-Vallespin S, Scott A, Ferreira P, Khalique Z, Pennell D, Firmin D. Cardiac Diffusion: Technique and Practical Applications. J Magn Reson Imaging 2019; 52:348-368. [PMID: 31482620 DOI: 10.1002/jmri.26912] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/13/2019] [Accepted: 08/14/2019] [Indexed: 12/12/2022] Open
Abstract
The 3D microarchitecture of the cardiac muscle underlies the mechanical and electrical properties of the heart. Cardiomyocytes are arranged helically through the depth of the wall, and their shortening leads to macroscopic torsion, twist, and shortening during cardiac contraction. Furthermore, cardiomyocytes are organized in sheetlets separated by shear layers, which reorientate, slip, and shear during macroscopic left ventricle (LV) wall thickening. Cardiac diffusion provides a means for noninvasive interrogation of the 3D microarchitecture of the myocardium. The fundamental principle of MR diffusion is that an MRI signal is attenuated by the self-diffusion of water in the presence of large diffusion-encoding gradients. Since water molecules are constrained by the boundaries in biological tissue (cell membranes, collagen layers, etc.), depicting their diffusion behavior elucidates the shape of the myocardial microarchitecture they are embedded in. Cardiac diffusion therefore provides a noninvasive means to understand not only the dynamic changes in cardiac microstructure of healthy myocardium during cardiac contraction but also the pathophysiological changes in the presence of disease. This unique and innovative technology offers tremendous potential to enable improved clinical diagnosis through novel microstructural and functional assessment. in vivo cardiac diffusion methods are immediately translatable to patients, opening new avenues for diagnostic investigation and treatment evaluation in a range of clinically important cardiac pathologies. This review article describes the 3D microstructure of the LV, explains in vivo and ex vivo cardiac MR diffusion acquisition and postprocessing techniques, as well as clinical applications to date. Level of Evidence: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019. J. Magn. Reson. Imaging 2020;52:348-368.
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Affiliation(s)
- Sonia Nielles-Vallespin
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Andrew Scott
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Pedro Ferreira
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Zohya Khalique
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - Dudley Pennell
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
| | - David Firmin
- Cardiovascular MR Unit, Royal Brompton And Harefield NHS Foundation Trust, London, UK.,NHLI, Imperial College of Science, Technology and Medicine, London, UK
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19
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Beyhoff N, Lohr D, Foryst-Ludwig A, Klopfleisch R, Brix S, Grune J, Thiele A, Erfinanda L, Tabuchi A, Kuebler WM, Pieske B, Schreiber LM, Kintscher U. Characterization of Myocardial Microstructure and Function in an Experimental Model of Isolated Subendocardial Damage. Hypertension 2019; 74:295-304. [PMID: 31291149 PMCID: PMC6635061 DOI: 10.1161/hypertensionaha.119.12956] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Subendocardial damage is among the first cardiac manifestations of hypertension and is already present in asymptomatic disease states. Accordingly, markers of subendocardial impairment may facilitate early detection of cardiac damages and risk stratification under these conditions. This study aimed to investigate the impact of subendocardial damage on myocardial microstructure and function to elucidate early pathophysiologic processes and to identify corresponding diagnostic measures. Mice (n=38) were injected with isoproterenol to induce isolated subendocardial scarring or saline as corresponding control. Cardiac function and myocardial deformation were determined by high-frequency echocardiography. The cardiac stress response was assessed in a graded exercise test and during dobutamine stress echocardiography. Myocardial microstructure was studied ex vivo by 7 T diffusion tensor magnetic resonance imaging at a spatial resolution of 100×100×100 µm 3 . Results were correlated with histology and biomarker expression. Subendocardial fibrosis was accompanied by diastolic dysfunction, impaired longitudinal deformation (global peak longitudinal strain [LS]: -12.5±0.5% versus -15.6±0.5%; P<0.001) and elevated biomarker expression (ANP [atrial natriuretic peptide], Galectin-3, and ST2). Systolic function and cardiac stress response remained preserved. Diffusion tensor magnetic resonance imaging revealed a left-shift in helix angle towards lower values in isoproterenol-treated animals, which was mainly determined by subepicardial myofibers (mean helix angle: 2.2±0.8° versus 5.9±1.0°; P<0.01). Longitudinal strain and subepicardial helix angle were highly predictive for subendocardial fibrosis (sensitivity, 82%-92% and specificity, 89%-90%). The results indicate that circumscribed subendocardial damage alone can cause several hallmarks observed in cardiovascular high-risk patients. Microstructural remodeling under these conditions involves also remote regions, and corresponding changes in longitudinal strain and helix angle might serve as diagnostic markers.
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Affiliation(s)
- Niklas Beyhoff
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.)
| | - David Lohr
- Chair of Cellular and Molecular Imaging, Comprehensive Heart Failure Center (CHFC), University Hospital Wuerzburg, Germany (D.L., L.M.S.)
| | - Anna Foryst-Ludwig
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.)
| | - Robert Klopfleisch
- Department of Veterinary Pathology, College of Veterinary Medicine, Freie Universität Berlin, Germany (R.K.)
| | - Sarah Brix
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.)
| | - Jana Grune
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.).,Charité-Universitaätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Physiology, Berlin, Germany (J.G., L.E., Arata Tabuchi, W.M.K.)
| | - Arne Thiele
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.)
| | - Lasti Erfinanda
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.).,Charité-Universitaätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Physiology, Berlin, Germany (J.G., L.E., Arata Tabuchi, W.M.K.)
| | - Arata Tabuchi
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.).,Charité-Universitaätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Physiology, Berlin, Germany (J.G., L.E., Arata Tabuchi, W.M.K.)
| | - Wolfgang M Kuebler
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.).,Charité-Universitaätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Physiology, Berlin, Germany (J.G., L.E., Arata Tabuchi, W.M.K.)
| | - Burkert Pieske
- DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.).,Department of Internal Medicine and Cardiology, Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin and Deutsches Herzzentrum Berlin (DHZB), Department of Cardiology, Berlin, Germany (B.P.)
| | - Laura M Schreiber
- Chair of Cellular and Molecular Imaging, Comprehensive Heart Failure Center (CHFC), University Hospital Wuerzburg, Germany (D.L., L.M.S.)
| | - Ulrich Kintscher
- From the Charité-Universitätsmedizin Berlin, corporate member of Freie Universitaät Berlin, Humboldt-Universitaät zu Berlin, and Berlin Institute of Health, Institute of Pharmacology, Center for Cardiovascular Research, Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, U.K.).,DZHK (German Centre for Cardiovascular Research), Partner site Berlin, Germany (N.B., A.F.-L., S.B., J.G., Arne Thiele, L.E., Arata Tabuchi, W.M.K., B.P., U.K.)
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20
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Sramko M, Hoogendoorn JC, Glashan CA, Zeppenfeld K. Advancement in cardiac imaging for treatment of ventricular arrhythmias in structural heart disease. Europace 2018; 21:383-403. [DOI: 10.1093/europace/euy150] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 07/23/2018] [Indexed: 12/28/2022] Open
Affiliation(s)
- Marek Sramko
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, ZA, Leiden, The Netherlands
| | - Jarieke C Hoogendoorn
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, ZA, Leiden, The Netherlands
| | - Claire A Glashan
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, ZA, Leiden, The Netherlands
| | - Katja Zeppenfeld
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, ZA, Leiden, The Netherlands
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21
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Crossman DJ, Shen X, Jüllig M, Munro M, Hou Y, Middleditch M, Shrestha D, Li A, Lal S, Dos Remedios CG, Baddeley D, Ruygrok PN, Soeller C. Increased collagen within the transverse tubules in human heart failure. Cardiovasc Res 2018; 113:879-891. [PMID: 28444133 DOI: 10.1093/cvr/cvx055] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 03/20/2017] [Indexed: 12/22/2022] Open
Abstract
Aims In heart failure transverse-tubule (t-tubule) remodelling disrupts calcium release, and contraction. T-tubules in human failing hearts exhibit increased labelling by wheat germ agglutinin (WGA), a lectin that binds to the dystrophin-associated glycoprotein complex. We hypothesized changes in this complex may explain the increased WGA labelling and contribute to t-tubule remodelling in the failing human heart. In this study we sought to identify the molecules responsible for this increased WGA labelling. Methods and results Confocal and super-resolution fluorescence microscopy and proteomic analyses were used to quantify left ventricle samples from healthy donors and patients with idiopathic dilated cardiomyopathy (IDCM). Confocal microscopy demonstrated both WGA and dystrophin were located at t-tubules. Super-resolution microscopy revealed that WGA labelling of t-tubules is largely located within the lumen while dystrophin was restricted to near the sarcolemma. Western blots probed with WGA reveal a 5.7-fold increase in a 140 kDa band in IDCM. Mass spectrometry identified this band as type VI collagen (Col-VI) comprised of α1(VI), α2(VI), and α3(VI) chains. Pertinently, mutations in Col-VI cause muscular dystrophy. Western blotting identified a 2.4-fold increased expression and 3.2-fold increased WGA binding of Col-VI in IDCM. Confocal images showed that Col-VI is located in the t-tubules and that their diameter increased in the IDCM samples. Super-resolution imaging revealed Col-VI was restricted to the t-tubule lumen where increases were associated with displacement in the sarcolemma as identified from dystrophin labelling. Samples were also labelled for type I, III, and IV collagen. Both confocal and super-resolution imaging identified that these collagens were also present within t-tubule lumen. Conclusion Increased expression and labelling of collagen in IDCM samples indicates fibrosis may contribute to t-tubule remodelling in human heart failure.
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Affiliation(s)
- David J Crossman
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand
| | - Xin Shen
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand
| | - Mia Jüllig
- School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland 1010, New Zealand
| | - Michelle Munro
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand
| | - Yufeng Hou
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand
| | - Martin Middleditch
- School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland 1010, New Zealand
| | - Darshan Shrestha
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand
| | - Amy Li
- Bosch Institute, University of Sydney, Fisher Road Sydney, NSW 2006, Australia
| | - Sean Lal
- Bosch Institute, University of Sydney, Fisher Road Sydney, NSW 2006, Australia
| | | | - David Baddeley
- Department of Cell Biology, Yale University, West Campus, 300 Heffernan Drive, Haven, CT 06515, USA
| | - Peter N Ruygrok
- Department of Cardiology, Auckland City Hospital, Auckland 1042, New Zealand
| | - Christian Soeller
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton, Auckland 1023, New Zealand.,Living Systems Institute and Biomedical Physics, University of Exeter, Stocker Road, Exeter EX4QL, UK
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22
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Wu R, An DA, Shi RY, Chen BH, Jiang M, Bacyinski A, Han TT, Hu J, Xu JR, Wu LM. Myocardial fibrosis evaluated by diffusion-weighted imaging and its relationship to 3D contractile function in patients with hypertrophic cardiomyopathy. J Magn Reson Imaging 2018; 48:1139-1146. [PMID: 29601139 DOI: 10.1002/jmri.26016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 03/02/2018] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Previous studies have shown that diffusion-weighted imaging (DWI) is sensitive to myocardial fibrosis in ischemic and nonischemic cardiomyopathy. PURPOSE To explore the prognostic value of apparent diffusion coefficient (ADC) for detecting myocardial fibrosis and its relationship to the contractile function in hypertrophic cardiomyopathy (HCM). STUDY TYPE Prospective. POPULATION A total of 45 HCM patients and 20 controls. FIELD STRENGTH/SEQUENCE 3.0T cardiac MRI. The cardiac MR sequences included cine, T1 mapping, and DWI. ASSESSMENT According to the presence of late gadolinium enhancement (LGE) and the extracellular volume (ECV) values (+2 SD of control subjects), respectively, reader W and reader J assessed the value of ADC of each segment for detecting myocardial fibrosis and its relationship to impaired contractile function in HCM patients. STATISTICAL TESTS Independent sample t-test, Pearson analysis, and intraclass correlation (ICC). RESULTS The value of ECV was 23.6 ± 3.0% for control. ECV ≥ 29.6% and ECV < 29.6% groups were classified. ADC values in the ECV ≥ 29.6% group were significantly increased compared to the ECV < 29.6% group, (2.41 ± 0.23 μm2 /ms vs. 2.03 ± 0.16 μm2 /ms, P < 0.005). Compared to the LGE - group, ECV (32.1 ± 2.3% vs. 29.0 ± 2.8%, P < 0.005) and ADC (2.60 ± 0.18 μm2 /ms vs. 2.10 ± 0.07 μm2 /ms, P < 0.005) values were significantly increased in the LGE + group. ADC values were linearly associated with ECV values (R2 = 0.65) in HCM patients. ADC values were linearly associated with circumferential and longitudinal strain (R2 = 0.60, R2 = 0.46), as well as circumferential, longitudinal, and radial strain rate (R2 = 0.13, R2 = 0.25, R2 = 0.17, respectively). DATA CONCLUSION Contractile dysfunction in HCM is predominantly associated with ADC, which is a feasible alternative to ECV and LGE for detecting myocardial fibrosis. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1139-1146.
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Affiliation(s)
- Rui Wu
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Dong-Aolei An
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ruo-Yang Shi
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Bing-Hua Chen
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Meng Jiang
- Department of Cardiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Andrew Bacyinski
- Department of Physical Medicine and Rehabilitation, Detroit Medical Center, Detroit, Michigan, USA
| | - Tong-Tong Han
- Circle Cardiovascular Imaging Inc., Calgary, AB, Canada
| | - Jiani Hu
- Department of Radiology, Wayne State University, Detroit, Michigan, USA
| | - Jian-Rong Xu
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Lian-Ming Wu
- Department of Radiology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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23
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Aliotta E, Moulin K, Magrath P, Ennis DB. Quantifying precision in cardiac diffusion tensor imaging with second-order motion-compensated convex optimized diffusion encoding. Magn Reson Med 2018; 80:1074-1087. [PMID: 29427349 DOI: 10.1002/mrm.27107] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Eric Aliotta
- Department of Radiological Sciences, University of California, Los Angeles, California.,Biomedical Physics Interdepartmental Program, University of California, Los Angeles, California
| | - Kévin Moulin
- Department of Radiological Sciences, University of California, Los Angeles, California
| | - Patrick Magrath
- Department of Bioengineering, University of California, Los Angeles, California
| | - Daniel B Ennis
- Department of Radiological Sciences, University of California, Los Angeles, California.,Biomedical Physics Interdepartmental Program, University of California, Los Angeles, California.,Department of Bioengineering, University of California, Los Angeles, California
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24
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Wu R, An DA, Hu J, Jiang M, Guo Q, Xu JR, Wu LM. The apparent diffusion coefficient is strongly correlated with extracellular volume, a measure of myocardial fibrosis, and subclinical cardiomyopathy in patients with systemic lupus erythematosus. Acta Radiol 2017; 59:287-295. [DOI: 10.1177/0284185117717763] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Extracellular volume (ECV) has been histologically validated as a non-invasive quantitative index of myocardial fibrosis that does not require the use of contrast, which is contraindicated in patients with renal insufficiency. Purpose To evaluate the correlation between the contrast-free apparent diffusion coefficient (ADC) and ECV, an index of fibrosis. Material and Methods Twenty-four patients with systemic lupus erythematosus (SLE), who were predominantly women (mean age = 36 ± 12 years) and 12 normal participants (mean age = 38 ± 10 years) underwent cardiac magnetic resonance (CMR) via 3.0 T MR with T1 mapping. Diffusion-weighted imaging (DWI) and late gadolinium-enhanced (LGE) imaging served as the reference standards with which CMR was compared. The mean ADC, native T1, and ECV were calculated for each patient, and the correlations among these parameters were analyzed. Results Both SLE LGE-positive (LGE+) and SLE LGE-negative (LGE–) participants had higher native T1 values, ECV, and ADC than normal controls ( P < 0.05). SLE LGE+ participants exhibited a higher ECV (0.31 ± 0.02) and ADC (2.44 ± 0.32 × 10−3 mm2/s) than SLE LGE– participants ( p < 0.05); however, SLE LGE+ and SLE LGE– participants had similar native T1 values (1227 ± 48.81 ms versus 1174.70 ± 95.80 ms, respectively; P > 0.05). ADC values were positively correlated with increased ECV (R2 = 0.62) and native T1 values (R2 = 0.28) in all participants. Conclusion ADC measurements are a suitable alternative to ECV that may be used to assess and quantify myocardial fibrosis in patients with SLE.
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Affiliation(s)
- Rui Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Dong-Aolei An
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Jiani Hu
- Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Meng Jiang
- Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Qiang Guo
- Department of Rheumatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Jian-Rong Xu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Lian-Ming Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
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25
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von Deuster C, Sammut E, Asner L, Nordsletten D, Lamata P, Stoeck CT, Kozerke S, Razavi R. Studying Dynamic Myofiber Aggregate Reorientation in Dilated Cardiomyopathy Using In Vivo Magnetic Resonance Diffusion Tensor Imaging. Circ Cardiovasc Imaging 2017; 9:CIRCIMAGING.116.005018. [PMID: 27729361 PMCID: PMC5068188 DOI: 10.1161/circimaging.116.005018] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 08/26/2016] [Indexed: 11/30/2022]
Abstract
Supplemental Digital Content is available in the text. Background— The objective of this study is to assess the dynamic alterations of myocardial microstructure and strain between diastole and systole in patients with dilated cardiomyopathy relative to healthy controls using the magnetic resonance diffusion tensor imaging, myocardial tagging, and biomechanical modeling. Methods and Results— Dual heart-phase diffusion tensor imaging was successfully performed in 9 patients and 9 controls. Tagging data were acquired for the diffusion tensor strain correction and cardiac motion analysis. Mean diffusivity, fractional anisotropy, and myocyte aggregate orientations were compared between both cohorts. Cardiac function was assessed by left ventricular ejection fraction, torsion, and strain. Computational modeling was used to study the impact of cardiac shape on fiber reorientation and how fiber orientations affect strain. In patients with dilated cardiomyopathy, a more longitudinal orientation of diastolic myofiber aggregates was measured compared with controls. Although a significant steepening of helix angles (HAs) during contraction was found in the controls, consistent change in HAs during contraction was absent in patients. Left ventricular ejection fraction, cardiac torsion, and strain were significantly lower in the patients compared with controls. Computational modeling revealed that the dilated heart results in reduced HA changes compared with a normal heart. Reduced torsion was found to be exacerbated by steeper HAs. Conclusions— Diffusion tensor imaging revealed reduced reorientation of myofiber aggregates during cardiac contraction in patients with dilated cardiomyopathy relative to controls. Left ventricular remodeling seems to be an important factor in the changes to myocyte orientation. Steeper HAs are coupled with a worsening in strain and torsion. Overall, the findings provide new insights into the structural alterations in patients with dilated cardiomyopathy.
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Affiliation(s)
- Constantin von Deuster
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - Eva Sammut
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - Liya Asner
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - David Nordsletten
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - Pablo Lamata
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - Christian T Stoeck
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
| | - Sebastian Kozerke
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.).
| | - Reza Razavi
- From the Department for Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, United Kingdom (C.v.D., E.S., L.A., D.N., P.L., C.T.S, S.K., R.R.); and Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, University and ETH Zurich, Switzerland (C.v.D., C.T.S., S.K.)
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26
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Fibrosis quantification in Hypertensive Heart Disease with LVH and Non-LVH: Findings from T1 mapping and Contrast-free Cardiac Diffusion-weighted imaging. Sci Rep 2017; 7:559. [PMID: 28373647 PMCID: PMC5428770 DOI: 10.1038/s41598-017-00627-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 03/08/2017] [Indexed: 01/19/2023] Open
Abstract
This study assessed the extent of fibrosis and the relationship between the ADC value and systolic strain in hypertensive patients with left ventricular hypertrophy (HTN LVH) and hypertensive patients without LVH (HTN non-LVH) using cardiac diffusion-weighted imaging and T1 mapping. T1 mapping was performed in 13 HTN LVH (mean age, 56.23 ± 3.30 years), 17 HTN non-LVH (mean age, 56.41 ± 2.78 years), and 12 normal control subjects (mean age, 55.67 ± 3.08 years) with 3.0 T MRI using cardiac diffusion-weighted imaging and T1 mapping. HTN LVH subjects had higher native T1 (1233.12 ± 79.01) compared with controls (1133.88 ± 27.40) (p < 0.05). HTN LVH subjects had higher ECV (0.28 ± 0.03) compared with HTN non-LVH subjects (0.26 ± 0.02) or controls (0.24 ± 0.03) (p < 0.05). HTN LVH subjects had higher ADC (2.23 ± 0.34) compared with HTN non-LVH subjects (1.88 ± 0.27) or controls (1.61 ± 0.38), (p < 0.05). Positive associations were noted between LVMI and ADC (Spearman = 0.450, p < 0.05) and between LVMI and ECV (Spearman = 0.181, p < 0.05). ADC was also related to an increase in ECV (R2 = 0.210). Increased levels of ADC were associated with reduced peak systolic and early diastolic circumferential strain rates across all subjects. Contrast-free DW-CMR is an alternative sequence to ECV for the evaluation of fibrosis extent in HTN LVH and HTN non-LVH, while native T1 has limited value.
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27
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Tran N, Giannakidis A, Gullberg GT, Seo Y. Quantitative analysis of hypertrophic myocardium using diffusion tensor magnetic resonance imaging. J Med Imaging (Bellingham) 2016; 3:046001. [PMID: 27872872 DOI: 10.1117/1.jmi.3.4.046001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 09/28/2016] [Indexed: 11/14/2022] Open
Abstract
Systemic hypertension is a causative factor in left ventricular hypertrophy (LVH). This study is motivated by the potential to reverse or manage the dysfunction associated with structural remodeling of the myocardium in this pathology. Using diffusion tensor magnetic resonance imaging, we present an analysis of myocardial fiber and laminar sheet orientation in ex vivo hypertrophic (6 SHR) and normal (5 WKY) rat hearts using the covariance of the diffusion tensor. First, an atlas of normal cardiac microstructure was formed using the WKY b0 images. Then, the SHR and WKY b0 hearts were registered to the atlas. The acquired deformation fields were applied to the SHR and WKY heart tensor fields followed by the preservation of principal direction (PPD) reorientation strategy. A mean tensor field was then formed from the registered WKY tensor images. Calculating the covariance of the registered tensor images about this mean for each heart, the hypertrophic myocardium exhibited significantly increased myocardial fiber derangement ([Formula: see text]) with a mean dispersion of 38.7 deg, and an increased dispersion of the laminar sheet normal ([Formula: see text]) of 54.8 deg compared with 34.8 deg and 51.8 deg, respectively, in the normal hearts. Results demonstrate significantly altered myocardial fiber and laminar sheet structure in rats with hypertensive LVH.
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Affiliation(s)
- Nicholas Tran
- University of California , Department of Radiology and Biomedical Imaging, Physics Research Laboratory, 185 Berry Street, Ste 350, San Francisco, United States
| | - Archontis Giannakidis
- Royal Brompton Hospital, Cardiovascular Biomedical Research Unit, Sydney Street, London SW3 6NP, United Kingdom; National Heart and Lung Institute, Imperial College London, Sydney Street, London SW3 6NP, United Kingdom; Lawrence Berkeley National Laboratory, Structural Biology and Imaging Department, One Cyclotron Road, Berkeley, California, United States
| | - Grant T Gullberg
- University of California, Department of Radiology and Biomedical Imaging, Physics Research Laboratory, 185 Berry Street, Ste 350, San Francisco, United States; Lawrence Berkeley National Laboratory, Structural Biology and Imaging Department, One Cyclotron Road, Berkeley, California, United States; University of California, Joint Graduate Group in Bioengineering, 1700 4th Street, San Francisco, United States
| | - Youngho Seo
- University of California, Department of Radiology and Biomedical Imaging, Physics Research Laboratory, 185 Berry Street, Ste 350, San Francisco, United States; Lawrence Berkeley National Laboratory, Structural Biology and Imaging Department, One Cyclotron Road, Berkeley, California, United States; University of California, Joint Graduate Group in Bioengineering, 1700 4th Street, San Francisco, United States; University of California, Department of Radiation Oncology, 1600 Divisadero Street, San Francisco, United States
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28
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Nguyen C, Fan Z, Xie Y, Pang J, Speier P, Bi X, Kobashigawa J, Li D. In vivo diffusion-tensor MRI of the human heart on a 3 tesla clinical scanner: An optimized second order (M2) motion compensated diffusion-preparation approach. Magn Reson Med 2016; 76:1354-1363. [PMID: 27550078 PMCID: PMC5067209 DOI: 10.1002/mrm.26380] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/23/2016] [Accepted: 07/22/2016] [Indexed: 12/13/2022]
Abstract
PURPOSE To optimize a diffusion-prepared balanced steady-state free precession cardiac MRI (CMR) technique to perform diffusion-tensor CMR (DT-CMR) in humans on a 3 Tesla clinical scanner METHODS: A previously developed second order motion compensated (M2) diffusion-preparation scheme was significantly shortened (40%) yielding sufficient signal-to-noise ratio for DT-CMR imaging. In 20 healthy volunteers and 3 heart failure (HF) patients, DT-CMR was performed comparing no motion compensation (M0), first order motion compensation (M1), and the optimized M2. Mean diffusivity (MD), fractional anisotropy (FA), helix angle (HA), and HA transmural slope (HATS) were calculated. Reproducibility and success rate (SR) were investigated. RESULTS M2-derived left ventricular (LV) MD, FA, and HATS (1.4 ± 0.2 μm2 /ms, 0.28 ± 0.06, -1.0 ± 0.2 °/%trans) were significantly (P < 0.001) less than M1 (1.8 ± 0.3 μm2 /ms, 0.46 ± 0.14, -0.1 ± 0.3 °/%trans) and M0 (4.8 ± 1.0 μm2 /ms, 0.70 ± 0.14, 0.1 ± 0.3 °/%trans) indicating less motion corruption and yielding values more consistent with previous literature. M2-derived DT-CMR parameters had higher reproducible (ICC > 0.85) and SR (82%) than M1 (ICC = 0.20-0.85; SR = 37%) and M0 (ICC = 0.20-0.30; SR = 11%). M2 DT-CMR was able to yield HA maps with smooth transmural transition from endocardium to epicardium. CONCLUSION The proposed M2 DT-CMR reproducibly yielded bulk motion robust estimations of mean LV MD, FA, HA, and HATS on a 3T clinical scanner. Magn Reson Med 76:1354-1363, 2016. © 2016 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Christopher Nguyen
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Zhaoyang Fan
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Yibin Xie
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Jianing Pang
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | | | - Xiaoming Bi
- Siemens Healthcare, Los Angeles, California, USA
| | - Jon Kobashigawa
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Debiao Li
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA.
- Department of Bioengineering, University of California Los Angeles, Los Angeles, California, USA.
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29
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Abdullah OM, Seidel T, Dahl M, Gomez AD, Yiep G, Cortino J, Sachse FB, Albertine KH, Hsu EW. Diffusion tensor imaging and histology of developing hearts. NMR IN BIOMEDICINE 2016; 29:1338-1349. [PMID: 27485033 PMCID: PMC5160010 DOI: 10.1002/nbm.3576] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 05/24/2016] [Accepted: 06/03/2016] [Indexed: 06/06/2023]
Abstract
Diffusion tensor imaging (DTI) has emerged as a promising method for noninvasive quantification of myocardial microstructure. However, the origin and behavior of DTI measurements during myocardial normal development and remodeling remain poorly understood. In this work, conventional and bicompartmental DTI in addition to three-dimensional histological correlation were performed in a sheep model of myocardial development from third trimester to postnatal 5 months of age. Comparing the earliest time points in the third trimester with the postnatal 5 month group, the scalar transverse diffusivities preferentially increased in both left ventricle (LV) and right ventricle (RV): secondary eigenvalues D2 increased by 54% (LV) and 36% (RV), whereas tertiary eigenvalues D3 increased by 85% (LV) and 67% (RV). The longitudinal diffusivity D1 changes were small, which led to a decrease in fractional anisotropy by 41% (LV) and 33% (RV) in 5 month versus fetal hearts. Histological analysis suggested that myocardial development is associated with hyperplasia in the early stages of the third trimester followed by myocyte growth in the later stages up to 5 months of age (increased average myocyte width by 198%, myocyte length by 128%, and decreased nucleus density by 70% between preterm and postnatal 5 month hearts.) In a few histological samples (N = 6), correlations were observed between DTI longitudinal diffusivity and myocyte length (r = 0.86, P < 0.05), and transverse diffusivity and myocyte width (r = 0.96, P < 0.01). Linear regression analysis showed that transverse diffusivities are more affected by changes in myocyte size and nucleus density changes than longitudinal diffusivities, which is consistent with predictions of classical models of diffusion in porous media. Furthermore, primary and secondary DTI eigenvectors during development changed significantly. Collectively, the findings demonstrate a role for DTI to monitor and quantify myocardial development, and potentially cardiac disease. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Osama M Abdullah
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA.
| | - Thomas Seidel
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - MarJanna Dahl
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Arnold David Gomez
- Department of Electrical Computer Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Gavin Yiep
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
| | - Julia Cortino
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
| | - Frank B Sachse
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Kurt H Albertine
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Edward W Hsu
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
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Wu LM, Chen BH, Yao QY, Ou YR, Wu R, Jiang M, Hu J, An DA, Xu JR. Quantitative diffusion-weighted magnetic resonance imaging in the assessment of myocardial fibrosis in hypertrophic cardiomyopathy compared with T1 mapping. Int J Cardiovasc Imaging 2016; 32:1289-97. [PMID: 27198892 DOI: 10.1007/s10554-016-0909-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/05/2016] [Indexed: 11/29/2022]
Abstract
To identify myocardial fibrosis in hypertrophic cardiomyopathy (HCM) subjects using quantitative cardiac diffusion-weighted imaging (DWI) and to compare its performance with native T1 mapping and extracellular volume (ECV). Thirty-eight HCM subjects (mean age, 53 ± 9 years) and 14 normal controls (mean age, 51 ± 8 years) underwent cardiac magnetic resonance imaging (CMRI) on a 3.0T magnetic resonance (MR) machine with DWI, T1 mapping and late gadolinium enhancement (LGE) imaging as the reference standard. The mean apparent diffusion coefficient (ADC), native T1 value and ECV were determined for each subject. Overall, the HCM subjects exhibited an increased native T1 value (1241.04 ± 78.50 ms), ECV (0.31 ± 0.03) and ADC (2.36 ± 0.34 s/mm(2)) compared with the normal controls (1114.60 ± 37.99 ms, 0.24 ± 0.04, and 1.62 ± 0.38 s/mm(2), respectively) (p < 0.05). DWI differentiated healthy and fibrotic myocardia with an area under the curve (AUC) of 0.93, while the AUCs of the native T1 values (0.93), (p > 0.05) and ECV (0.94), (p > 0.05) exhibited an equal differentiation ability. Both HCM LGE+ and HCM LGE- subjects had an increased native T1 value, ECV and ADC compared to the normal controls (p < 0.05). HCM LGE+ subjects exhibited an increased ECV (0.31 ± 0.04) and ADC (2.43 ± 0.36 s/mm(2)) compared to HCM LGE- subjects (p < 0.05). HCM LGE+ and HCM LGE- subjects had similar native T1 values (1250 ± 76.36 ms vs. 1213.98 ± 92.30 ms, respectively) (p > 0.05). ADC values were linearly associated with increased ECV (R(2) = 0.36) and native T1 values (R(2) = 0.40) among all subjects. DWI is a feasible alternative to native T1 mapping and ECV for the identification of myocardial fibrosis in patients with HCM. DWI and ECV can quantitatively characterize the extent of fibrosis in HCM LGE+ and HCM LGE- patients.
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Affiliation(s)
- Lian-Ming Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Bing-Hua Chen
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qiu-Ying Yao
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yang-Rongzheng Ou
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Rui Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Meng Jiang
- Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jiani Hu
- Department of Radiology, Wayne State University, Detroit, MI, USA
| | - Dong-Aolei An
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jian-Rong Xu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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31
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Giannakidis A, Gullberg GT, Pennell DJ, Firmin DN. Value of Formalin Fixation for the Prolonged Preservation of Rodent Myocardial Microanatomical Organization: Evidence by MR Diffusion Tensor Imaging. Anat Rec (Hoboken) 2016; 299:878-87. [PMID: 27111575 DOI: 10.1002/ar.23359] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 02/10/2016] [Accepted: 03/14/2016] [Indexed: 11/08/2022]
Abstract
Previous ex vivo diffusion tensor imaging (DTI) studies on formalin-fixed myocardial tissue assumed that, after some initial changes in the first 48 hr since the start of fixation, DTI parameters remain stable over time. Prolonged preservation of cardiac tissue in formalin prior to imaging has been seen many times in the DTI literature as it is considered orderly. Our objective is to define the effects of the prolonged cardiac tissue exposure to formalin on tissue microanatomical organization, as this is assessed by DTI parameters. DTI experiments were conducted on eight excised rodent hearts that were fixed by immersion in formalin. The samples were randomly divided into two equinumerous groups corresponding to shorter (∼2 weeks) and more prolonged (∼6-8 weeks) durations of tissue exposure to formalin prior to imaging. We found that when the duration of cardiac tissue exposure to formalin before imaging increased, water diffusion became less restricted, helix angle (HA) histograms flattened out and exhibited heavier tails (even though the classic HA transmural variation was preserved), and a significant loss of inter-voxel primary diffusion orientation integrity was introduced. The prolonged preservation of cardiac tissue in formalin profoundly affected its microstructural organization, as this was assessed by DTI parameters. The accurate interpretation of diffusivity profiles necessitates awareness of the pitfalls of prolonged cardiac tissue exposure duration to formalin. The acquired knowledge works to the advantage of a proper experimental design of DTI studies of fixed hearts. Anat Rec, 299:878-887, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Archontis Giannakidis
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK.,Life Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Grant T Gullberg
- Life Sciences, Lawrence Berkeley National Laboratory, Berkeley, California, USA.,Department of Radiology and Biomedical Imaging, University California San Francisco, San Francisco, California, USA
| | - Dudley J Pennell
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - David N Firmin
- NIHR Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
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32
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Merchant SS, Gomez AD, Morgan JL, Hsu EW. Parametric Modeling of the Mouse Left Ventricular Myocardial Fiber Structure. Ann Biomed Eng 2016; 44:2661-73. [PMID: 26942586 DOI: 10.1007/s10439-016-1574-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/17/2016] [Indexed: 12/26/2022]
Abstract
Magnetic resonance diffusion tensor imaging (DTI) has greatly facilitated detailed quantifications of myocardial structures. However, structural patterns, such as the distinctive transmural rotation of the fibers, remain incompletely described. To investigate the validity and practicality of pattern-based analysis, 3D DTI was performed on 13 fixed mouse hearts and fiber angles in the left ventricle were transformed and fitted to parametric expressions constructed from elementary functions of the prolate spheroidal spatial variables. It was found that, on average, the myocardial fiber helix angle could be represented to 6.5° accuracy by the equivalence of a product of 10th-order polynomials of the radial and longitudinal variables, and 17th-order Fourier series of the circumferential variable. Similarly, the fiber imbrication angle could be described by 10th-order polynomials and 24th-order Fourier series, to 5.6° accuracy. The representations, while relatively concise, did not adversely affect the information commonly derived from DTI datasets including the whole-ventricle mean fiber helix angle transmural span and atlases constructed for the group. The unique ability of parametric models for predicting the 3D myocardial fiber structure from finite number of 2D slices was also demonstrated. These findings strongly support the principle of parametric modeling for characterizing myocardial structures in the mouse and beyond.
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Affiliation(s)
- Samer S Merchant
- Department of Bioengineering, University of Utah, 36 S Wasatch Dr Rm 3100, Salt Lake City, UT, 84112, USA.
| | - Arnold David Gomez
- Department of Bioengineering, University of Utah, 36 S Wasatch Dr Rm 3100, Salt Lake City, UT, 84112, USA
- Division of Cardiothoracic Surgery, University of Utah, Salt Lake City, UT, USA
| | - James L Morgan
- Department of Bioengineering, University of Utah, 36 S Wasatch Dr Rm 3100, Salt Lake City, UT, 84112, USA
| | - Edward W Hsu
- Department of Bioengineering, University of Utah, 36 S Wasatch Dr Rm 3100, Salt Lake City, UT, 84112, USA
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33
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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] [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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Nguyen C, Lu M, Fan Z, Bi X, Kellman P, Zhao S, Li D. Contrast-free detection of myocardial fibrosis in hypertrophic cardiomyopathy patients with diffusion-weighted cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2015; 17:107. [PMID: 26631061 PMCID: PMC4668676 DOI: 10.1186/s12968-015-0214-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 11/24/2015] [Indexed: 11/12/2022] Open
Abstract
BACKGROUNDS Previous studies have shown that diffusion-weighted cardiovascular magnetic resonance (DW-CMR) is highly sensitive to replacement fibrosis of chronic myocardial infarction. Despite this sensitivity to myocardial infarction, DW-CMR has not been established as a method to detect diffuse myocardial fibrosis. We propose the application of a recently developed DW-CMR technique to detect diffuse myocardial fibrosis in hypertrophic cardiomyopathy (HCM) patients and compare its performance with established CMR techniques. METHODS HCM patients (N = 23) were recruited and scanned with the following protocol: standard morphological localizers, DW-CMR, extracellular volume (ECV) CMR, and late gadolinium enhanced (LGE) imaging for reference. Apparent diffusion coefficient (ADC) and ECV maps were segmented into 6 American Heart Association (AHA) segments. Positive regions for myocardial fibrosis were defined as: ADC > 2.0 μm(2)/ms and ECV > 30%. Fibrotic and non-fibrotic mean ADC and ECV values were compared as well as ADC-derived and ECV-derived fibrosis burden. In addition, fibrosis regional detection was compared between ADC and ECV calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) using ECV as the gold-standard reference. RESULTS ADC (2.4 ± 0.2 μm(2)/ms) of fibrotic regions (ADC > 2.0 μm(2)/ms) was significantly (p < 0.01) higher than ADC (1.5 ± 0.2 μm(2)/ms) of non-fibrotic regions. Similarly, ECV (35 ± 4%) of fibrotic regions (ECV > 30%) was significantly (p < 0.01) higher than ECV (26 ± 2%) of non-fibrotic regions. In fibrotic regions defined by ECV, ADC (2.2 ± 0.3 μm(2)/ms) was again significantly (p < 0.05) higher than ADC (1.6 ± 0.3 μm(2)/ms) of non-fibrotic regions. In fibrotic regions defined by ADC criterion, ECV (34 ± 5%) was significantly (p < 0.01) higher than ECV (28 ± 3%) in non-fibrotic regions. ADC-derived and ECV-derived fibrosis burdens were in substantial agreement (intra-class correlation = 0.83). Regional detection between ADC and ECV of diffuse fibrosis yielded substantial agreement (κ = 0.66) with high sensitivity, specificity, PPV, NPV, and accuracy (0.80, 0.85, 0.81, 0.85, and 0.83, respectively). CONCLUSION DW-CMR is sensitive to diffuse myocardial fibrosis and is capable of characterizing the extent of fibrosis in HCM patients.
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Affiliation(s)
- Christopher Nguyen
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA, USA.
| | - Minjie Lu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Beijing, China.
- National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China.
| | - Zhaoyang Fan
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Xiaoming Bi
- MR R&D, Siemens Healthcare, Los Angeles, CA, USA.
| | - Peter Kellman
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Shihua Zhao
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, Beijing, China.
- National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, China.
| | - Debiao Li
- Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Department of Bioengineering, University of California Los Angeles, Los Angeles, CA, USA.
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35
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Abdullah OM, Gomez AD, Merchant S, Heidinger M, Poelzing S, Hsu EW. Orientation dependence of microcirculation-induced diffusion signal in anisotropic tissues. Magn Reson Med 2015; 76:1252-62. [PMID: 26511215 DOI: 10.1002/mrm.25980] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/17/2015] [Accepted: 08/20/2015] [Indexed: 12/12/2022]
Abstract
PURPOSE To seek a better understanding of the effect of organized capillary flow on the MR diffusion-weighted signal. METHODS A theoretical framework was proposed to describe the diffusion-weighted MR signal, which was then validated both numerically using a realistic model of capillary network and experimentally in an animal model of isolated perfused heart preparation with myocardial blood flow verified by means of direct arterial spin labeling measurements. RESULTS Microcirculation in organized tissues gave rise to an MR signal that could be described as a combination of the bi-exponential behavior of conventional intravoxel incoherent motion (IVIM) theory and diffusion tensor imaging (DTI) -like anisotropy of the vascular signal, with the flow-related pseudo diffusivity represented as the linear algebraic product between the encoding directional unit vector and an appropriate tensor entity. Very good agreement between theoretical predictions and both numerical and experimental observations were found. CONCLUSION These findings suggest that the DTI formalism of anisotropic spin motion can be incorporated into the classical IVIM theory to describe the MR signal arising from diffusion and microcirculation in organized tissues. Magn Reson Med 76:1252-1262, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Osama M Abdullah
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA.
| | - Arnold David Gomez
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA.,Division of Cardiothoracic Surgery, University of Utah, Salt Lake City, Utah, USA
| | - Samer Merchant
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA
| | - Michael Heidinger
- Nora Eccles Harrison Cardiovascular Research and Training Institute (CVRTI), University of Utah, Salt Lake City, Utah, USA
| | - Steven Poelzing
- Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences, Blacksburg, Virginia, USA
| | - Edward W Hsu
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA
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36
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Siu AG, Ramadeen A, Hu X, Morikawa L, Zhang L, Lau JYC, Liu G, Pop M, Connelly KA, Dorian P, Wright GA. Characterization of the ultrashort-TE (UTE) MR collagen signal. NMR IN BIOMEDICINE 2015; 28:1236-1244. [PMID: 26268158 DOI: 10.1002/nbm.3372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 06/26/2015] [Accepted: 07/16/2015] [Indexed: 06/04/2023]
Abstract
Although current cardiovascular MR (CMR) techniques for the detection of myocardial fibrosis have shown promise, they nevertheless depend on gadolinium-based contrast agents and are not specific to collagen. In particular, the diagnosis of diffuse myocardial fibrosis, a precursor of heart failure, would benefit from a non-invasive imaging technique that can detect collagen directly. Such a method could potentially replace the need for endomyocardial biopsy, the gold standard for the diagnosis of the disease. The objective of this study was to measure the MR properties of collagen using ultrashort TE (UTE), a technique that can detect short T2* species. Experiments were performed in collagen solutions. Via a model of bi-exponential T2* with oscillation, a linear relationship (slope = 0.40 ± 0.01, R(2) = 0.99696) was determined between the UTE collagen signal fraction associated with these properties and the measured collagen concentration in solution. The UTE signal of protons in the collagen molecule was characterized as having a mean T2* of 0.75 ± 0.05 ms and a mean chemical shift of -3.56 ± 0.01 ppm relative to water at 7 T. The results indicated that collagen can be detected and quantified using UTE. A knowledge of the collagen signal properties could potentially be beneficial for the endogenous detection of myocardial fibrosis.
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Affiliation(s)
- Adrienne G Siu
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Cardiovascular Sciences Collaborative Program, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Andrew Ramadeen
- Keenan Research Center, Li Ka Shing Knowledge Institute, Toronto, ON, Canada
| | - Xudong Hu
- Keenan Research Center, Li Ka Shing Knowledge Institute, Toronto, ON, Canada
| | - Lily Morikawa
- Center for Modeling Human Disease, Toronto Center for Phenogenomics, Toronto, ON, Canada
| | - Li Zhang
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Justin Y C Lau
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Garry Liu
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Mihaela Pop
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Kim A Connelly
- Cardiovascular Sciences Collaborative Program, University of Toronto, Toronto, ON, Canada
- Keenan Research Center, Li Ka Shing Knowledge Institute, Toronto, ON, Canada
- Division of Cardiology, St. Michael's Hospital, Toronto, ON, Canada
| | - Paul Dorian
- Cardiovascular Sciences Collaborative Program, University of Toronto, Toronto, ON, Canada
- Keenan Research Center, Li Ka Shing Knowledge Institute, Toronto, ON, Canada
- Division of Cardiology, St. Michael's Hospital, Toronto, ON, Canada
| | - Graham A Wright
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
- Cardiovascular Sciences Collaborative Program, University of Toronto, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
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37
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David Gomez A, Bull DA, Hsu EW. Finite-Element Extrapolation of Myocardial Structure Alterations Across the Cardiac Cycle in Rats. J Biomech Eng 2015; 137:101010. [PMID: 26299478 DOI: 10.1115/1.4031419] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Indexed: 11/08/2022]
Abstract
Myocardial microstructures are responsible for key aspects of cardiac mechanical function. Natural myocardial deformation across the cardiac cycle induces measurable structural alteration, which varies across disease states. Diffusion tensor magnetic resonance imaging (DT-MRI) has become the tool of choice for myocardial structural analysis. Yet, obtaining the comprehensive structural information of the whole organ, in 3D and time, for subject-specific examination is fundamentally limited by scan time. Therefore, subject-specific finite-element (FE) analysis of a group of rat hearts was implemented for extrapolating a set of initial DT-MRI to the rest of the cardiac cycle. The effect of material symmetry (isotropy, transverse isotropy, and orthotropy), structural input, and warping approach was observed by comparing simulated predictions against in vivo MRI displacement measurements and DT-MRI of an isolated heart preparation at relaxed, inflated, and contracture states. Overall, the results indicate that, while ventricular volume and circumferential strain are largely independent of the simulation strategy, structural alteration predictions are generally improved with the sophistication of the material model, which also enhances torsion and radial strain predictions. Moreover, whereas subject-specific transversely isotropic models produced the most accurate descriptions of fiber structural alterations, the orthotropic models best captured changes in sheet structure. These findings underscore the need for subject-specific input data, including structure, to extrapolate DT-MRI measurements across the cardiac cycle.
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38
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Beliveau P, Cheriet F, Anderson SA, Taylor JL, Arai AE, Hsu LY. Quantitative assessment of myocardial fibrosis in an age-related rat model by ex vivo late gadolinium enhancement magnetic resonance imaging with histopathological correlation. Comput Biol Med 2015; 65:103-13. [PMID: 26313531 DOI: 10.1016/j.compbiomed.2015.07.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 07/28/2015] [Accepted: 07/29/2015] [Indexed: 10/23/2022]
Abstract
Late gadolinium enhanced (LGE) cardiac magnetic resonance (CMR) imaging can detect the presence of myocardial infarction from ischemic cardiomyopathies (ICM). However, it is more challenging to detect diffuse myocardial fibrosis from non-ischemic cardiomyopathy (NICM) with this technique due to more subtle and heterogeneous enhancement of the myocardium. This study investigates whether high-resolution LGE CMR can detect age-related myocardial fibrosis using quantitative texture analysis with histological validation. LGE CMR of twenty-four rat hearts (twelve 6-week-old and twelve 2-year-old) was performed using a 7T MRI scanner. Picrosirius red was used as the histopathology reference for collagen staining. Fibrosis in the myocardium was quantified with standard deviation (SD) threshold methods from the LGE CMR images and 3D contrast texture maps that were computed from gray level co-occurrence matrix of the CMR images. There was a significant increase of collagen fibers in the aged compared to the young rat histology slices (2.60±0.27 %LV vs. 1.24±0.29 %LV, p<0.01). Both LGE CMR and texture images showed a significant increase of myocardial fibrosis in the elderly compared to the young rats. Fibrosis in the LGE CMR images correlated strongly with histology with the 3 SD threshold (r=0.84, y=0.99x+0.00). Similarly, fibrosis in the contrast texture maps correlated with the histology using the 4 SD threshold (r=0.89, y=1.01x+0.00). High resolution ex-vivo LGE CMR can detect the presence of diffuse fibrosis that naturally developed in elderly rat hearts. Our results suggest that texture analysis may improve the assessment of myocardial fibrosis in LGE CMR images.
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Affiliation(s)
- Pascale Beliveau
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA; Institute of Biomedical Engineering, Ecole Polytechnique of Montreal, Montreal, Canada
| | - Farida Cheriet
- Institute of Biomedical Engineering, Ecole Polytechnique of Montreal, Montreal, Canada
| | - Stasia A Anderson
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Joni L Taylor
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Andrew E Arai
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Li-Yueh Hsu
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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