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Scott AD, Wen K, Luo Y, Huang J, Gover S, Soundarajan R, Ferreira PF, Pennell DJ, Nielles-Vallespin S. The effects of field strength on stimulated echo and motion compensated spin echo diffusion tensor cardiovascular magnetic resonance sequences. J Cardiovasc Magn Reson 2024:101052. [PMID: 38936803 DOI: 10.1016/j.jocmr.2024.101052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/03/2024] [Accepted: 06/19/2024] [Indexed: 06/29/2024] Open
Abstract
BACKGROUND In-vivo diffusion tensor CMR (DT-CMR) is an emerging technique for microstructural tissue characterisation in the myocardium. Most studies are performed at 3T, where higher signal to noise ratio (SNR) should benefit this signal starved method. However, a few studies have suggested that DT-CMR is possible at 1.5T, where EPI artefacts may be less severe and 1.5T hardware is more widely available. METHODS We recruited 20 healthy volunteers and performed mid-ventricular short axis DT-CMR at 1.5 T and 3 T. Acquisitions were performed at peak systole and end-diastole using both stimulated echo acquisition mode (STEAM) and motion compensated spin-echo (MCSE) sequences at matched spatial resolutions. DT-CMR parameters were averaged over the LV and compared between 1.5 T and 3 T sequences using both datasets with and without the blow reference data included. RESULTS Eleven (1.5T) and 12 (3T) diastolic MCSE acquisitions were rejected as the helix angle (HA) demonstrated <50% normal appearance circumferentially or the acquisition was abandoned due to poor image quality; a maximum of one acquisition was rejected for other datasets. Subjective HA map quality was significantly better at 3T than 1.5T for STEAM (p<0.05), but not for MCSE and other DT-CMR quality measures were consistent with improvements in STEAM at 3T over 1.5T. When blow data was excluded, no significant differences in mean diffusivity were observed between field strengths, but fractional anisotropy was significantly higher at 1.5T than 3T for STEAM systole (p<0.05). Absolute second eigenvector orientation (E2A, sheetlet angle) was significantly higher at 1.5T than 3T for MCSE systole and STEAM diastole, but significantly lower for STEAM systole (all p<0.05). Transmural HA distribution was less steep at 1.5T than 3T for STEAM diastole data (p<0.05). SNR in the blow images was higher at 3T than 1.5T for all acquisitions (p<0.05). CONCLUSION While 3T provides benefits in terms of SNR, both STEAM and MCSE can be performed at 1.5T. However, MCSE is unreliable in diastole at both field strengths and STEAM benefits from the improved SNR at 3T over 1.5T. Future clinical research studies may be able to leverage the wider availability of 1.5T CMR hardware where MCSE acquisitions are desirable.
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Affiliation(s)
- Andrew D Scott
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY.
| | - Ke Wen
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY; EPSRC Centre for Doctoral Training in Smart Medical Imaging. King's College London and Imperial College London, 5th Floor Beckett House, 1 Lambeth Palace Road, London, UK, SE1 7EU
| | - Yaqing Luo
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY; EPSRC Centre for Doctoral Training in Smart Medical Imaging. King's College London and Imperial College London, 5th Floor Beckett House, 1 Lambeth Palace Road, London, UK, SE1 7EU
| | - Jiahao Huang
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; Department of Bioengineering, Imperial College London, Royal School of Mines, Exhibition Road, London, UK SW7 2AZ
| | - Simon Gover
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP
| | - Rajkumar Soundarajan
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP
| | - Pedro F Ferreira
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY
| | - Dudley J Pennell
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY
| | - Sonia Nielles-Vallespin
- Cardiovascular Magnetic Resonance Unit, Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, Sydney Street, London, UK, SW3 6NP; National Heart and Lung Institute, Imperial College, Dovehouse Street, London, UK, SW3 6LY
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Sadighi M, Kara D, Mai D, Nguyen K, Chen S, Kwon D, Nguyen C. Cardiac DTI using short-axis PROPELLER: A feasibility study. Magn Reson Med 2024; 91:2546-2558. [PMID: 38376096 PMCID: PMC11102807 DOI: 10.1002/mrm.30020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 12/06/2023] [Accepted: 01/08/2024] [Indexed: 02/21/2024]
Abstract
PURPOSE We aimed to develop a free-breathing (FB) cardiac DTI (cDTI) method based on short-axis PROPELLER (SAP) and M2 motion compensated spin-echo EPI (SAP-M2-EPI) to mitigate geometric distortion and eliminate aliasing in acquired diffusion-weighted (DW) images, particularly in patients with a higher body mass index (BMI). THEORY AND METHODS The study involved 10 healthy volunteers whose BMI values fell into specific categories: BMI <25 (4 volunteers), 25< BMI <28 (5 volunteers), and BMI >30 (1 volunteer). We compared DTI parameters, including fractional anisotropy (FA), mean diffusivity (MD), and helix angle transmurality (HAT), between SAP-M2-EPI and M2-ssEPI. To evaluate the performance of SAP-M2-EPI in reducing geometric distortions in the left ventricle (LV) compared to CINE and M2-ssEPI, we utilized the DICE similarity coefficient (DSC) and assessed misregistration area. RESULTS In all volunteers, SAP-M2-EPI yielded high-quality LV DWIs without aliasing, demonstrating significantly reduced geometric distortion (with an average DSC of 0.92 and average misregistration area of 90 mm2) and diminished signal loss due to bulk motion when compared to M2-ssEPI. DTI parameter maps exhibited consistent patterns across slices without motion related artifacts. CONCLUSION SAP-M2-EPI facilitates free-breathing cDTI of the entire LV, effectively eliminating aliasing and minimizing geometric distortion compared to M2-ssEPI. Furthermore, it preserves accurate quantification of myocardial microstructure.
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Affiliation(s)
- Mehdi Sadighi
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Danielle Kara
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Dingheng Mai
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Case Western Reserve University, Cleveland, Ohio, USA
| | - Khoi Nguyen
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Shi Chen
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Deborah Kwon
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Imaging Institute,Cleveland Clinic, Cleveland, Ohio, USA
| | - Christopher Nguyen
- Cardiovascular Innovation Research Center (CIRC), Heart, Vascular, and Thoracic Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Case Western Reserve University, Cleveland, Ohio, USA
- Imaging Institute,Cleveland Clinic, Cleveland, Ohio, USA
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Rock CA, Chen YI, Wang R, Philip AL, Keil B, Weiner RB, Elmariah S, Mekkaoui C, Nguyen CT, Sosnovik DE. Diffusion Tensor Phenomapping of the Healthy and Pressure-Overloaded Human Heart. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.03.24306781. [PMID: 38746173 PMCID: PMC11092740 DOI: 10.1101/2024.05.03.24306781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Current techniques to image the microstructure of the heart with diffusion tensor MRI (DTI) are highly under-resolved. We present a technique to improve the spatial resolution of cardiac DTI by almost 10-fold and leverage this to measure local gradients in cardiomyocyte alignment or helix angle (HA). We further introduce a phenomapping approach based on voxel-wise hierarchical clustering of these gradients to identify distinct microstructural microenvironments in the heart. Initial development was performed in healthy volunteers (n=8). Thereader, subjects with severe but well-compensated aortic stenosis (AS, n=10) were compared to age-matched controls (CTL, n=10). Radial HA gradient was significantly reduced in AS (8.0±0.8°/mm vs. 10.2±1.8°/mm, p=0.001) but the other HA gradients did not change significantly. Four distinct microstructural clusters could be idenJfied in both the CTL and AS subjects and did not differ significantly in their properties or distribution. Despite marked hypertrophy, our data suggest that the myocardium in well-compensated AS can maintain its microstructural coherence. The described phenomapping approach can be used to characterize microstructural plasticity and perturbation in any organ system and disease.
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Tous C, Jodoin A, Pontré B, Grabs D, Begon M, Bureau NJ, Van Houten E. Characterizing the Myoarchitecture of the Supraspinatus and Infraspinatus Muscles With MRI Using Diffusion Tensor Imaging. J Magn Reson Imaging 2024; 59:851-862. [PMID: 37316960 DOI: 10.1002/jmri.28840] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/16/2023] Open
Abstract
BACKGROUND The societal cost of shoulder disabilities in our aging society keeps rising. Providing biomarkers of early changes in the microstructure of rotator cuff (RC) muscles might improve surgical planning. Elevation angle (E1A) and pennation angle (PA) assessed by ultrasound change with RC tears. Furthermore, ultrasounds lack repeatability. PURPOSE To propose a repeatable framework to quantify the myocyte angulation in RC muscles. STUDY TYPE Prospective. SUBJECTS Six asymptomatic healthy volunteers (1 female aged 30 years; 5 males, mean age 35 years, range 25-49 years), who underwent three repositioned scanning sessions (10 minutes apart) of the right infraspinatus muscle (ISPM) and supraspinatus muscle (SSPM). FIELD STRENGTH/SEQUENCE 3-T, T1-weighted and diffusion tensor imaging (DTI; 12 gradient encoding directions, b-values of 500 and 800 s/mm2 ). ASSESSMENT Each voxel was binned in percentage of depth defined by the shortest distance in the antero-posterior direction (manual delineation), i.e. the radial axis. A second order polynomial fit for PA across the muscle depth was used, while E1A described a sigmoid across depth: E 1 A sig = E 1 A range × sigmf 1 : 100 % depth , - EA 1 grad , E 1 A asym + E 1 A shift . STATISTICAL TESTS Repeatability was assessed with the nonparametric Wilcoxon's rank-sum test for paired comparisons across repeated scans in each volunteer for each anatomical muscle region and across repeated measures of the radial axis. A P-value <0.05 was considered statistically significant. RESULTS In the ISPM, E1A was constantly negative, became helicoidal, then mainly positive across the antero-posterior depth, respective at the caudal, central and cranial regions. In the SSPM, posterior myocytes ran more parallel to the intramuscular tendon ( PA ≈ 0 ° ), while anterior myocytes inserted with a pennation angle ( PA ≈ - 20 ° ). E1A and PA were repeatable in each volunteer (error < 10%). Intra-repeatability of the radial axis was achieved (error < 5%). DATA CONCLUSION ElA and PA in the proposed framework of the ISPM and SSPM are repeatable with DTI. Variations of myocyte angulation in the ISPM and SSPM can be quantified across volunteers. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Cyril Tous
- Research Center, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
| | - Alexandre Jodoin
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, Canada
| | - Beau Pontré
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
| | - Detlev Grabs
- Department of Anatomy, Université du Québec à Trois-Rivières, Trois-Rivières, Quebec, Canada
| | - Mikael Begon
- École de kinésiologie et des sciences de l'activité physique, Centre d'éducation physique et des sports de l'Université de Montréal, Montréal, Québec, Canada
| | - Nathalie J Bureau
- Research Center, Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada
- Department of Radiology, Centre hospitalier de l'Université de Montréal (CHUM), Montreal, Quebec, Canada
| | - Elijah Van Houten
- Department of Mechanical Engineering, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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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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Dejea H, Schlepütz CM, Méndez-Carmona N, Arnold M, Garcia-Canadilla P, Longnus SL, Stampanoni M, Bijnens B, Bonnin A. A tomographic microscopy-compatible Langendorff system for the dynamic structural characterization of the cardiac cycle. Front Cardiovasc Med 2022; 9:1023483. [PMID: 36620622 PMCID: PMC9815149 DOI: 10.3389/fcvm.2022.1023483] [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: 08/19/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022] Open
Abstract
Introduction Cardiac architecture has been extensively investigated ex vivo using a broad spectrum of imaging techniques. Nevertheless, the heart is a dynamic system and the structural mechanisms governing the cardiac cycle can only be unveiled when investigating it as such. Methods This work presents the customization of an isolated, perfused heart system compatible with synchrotron-based X-ray phase contrast imaging (X-PCI). Results Thanks to the capabilities of the developed setup, it was possible to visualize a beating isolated, perfused rat heart for the very first time in 4D at an unprecedented 2.75 μm pixel size (10.6 μm spatial resolution), and 1 ms temporal resolution. Discussion The customized setup allows high-spatial resolution studies of heart architecture along the cardiac cycle and has thus the potential to serve as a tool for the characterization of the structural dynamics of the heart, including the effects of drugs and other substances able to modify the cardiac cycle.
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Affiliation(s)
- Hector Dejea
- Paul Scherrer Institute, Villigen, Switzerland,Institute for Biomedical Engineering, University and ETH Zürich, Zurich, Switzerland,*Correspondence: Hector Dejea ✉
| | | | - Natalia Méndez-Carmona
- Department of Cardiac Surgery, Inselspital, Bern University Hospital, Bern, Switzerland,Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Maria Arnold
- Department of Cardiac Surgery, Inselspital, Bern University Hospital, Bern, Switzerland,Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Patricia Garcia-Canadilla
- BCNatal-Barcelona Center for Maternal-Fetal and Neonatal Medicine, Hospital Sant Joan de Déu and Hospital Clínic, University of Barcelona, Barcelona, Spain,Cardiovascular Diseases and Child Development, Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
| | - Sarah L. Longnus
- Department of Cardiac Surgery, Inselspital, Bern University Hospital, Bern, Switzerland,Department for BioMedical Research, University of Bern, Bern, Switzerland
| | - Marco Stampanoni
- Paul Scherrer Institute, Villigen, Switzerland,Institute for Biomedical Engineering, University and ETH Zürich, Zurich, Switzerland
| | - Bart Bijnens
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain,Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Anne Bonnin
- Paul Scherrer Institute, Villigen, Switzerland
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Wilson AJ, Sands GB, LeGrice IJ, Young AA, Ennis DB. Myocardial mesostructure and mesofunction. Am J Physiol Heart Circ Physiol 2022; 323:H257-H275. [PMID: 35657613 PMCID: PMC9273275 DOI: 10.1152/ajpheart.00059.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/22/2022]
Abstract
The complex and highly organized structural arrangement of some five billion cardiomyocytes directs the coordinated electrical activity and mechanical contraction of the human heart. The characteristic transmural change in cardiomyocyte orientation underlies base-to-apex shortening, circumferential shortening, and left ventricular torsion during contraction. Individual cardiomyocytes shorten ∼15% and increase in diameter ∼8%. Remarkably, however, the left ventricular wall thickens by up to 30-40%. To accommodate this, the myocardium must undergo significant structural rearrangement during contraction. At the mesoscale, collections of cardiomyocytes are organized into sheetlets, and sheetlet shear is the fundamental mechanism of rearrangement that produces wall thickening. Herein, we review the histological and physiological studies of myocardial mesostructure that have established the sheetlet shear model of wall thickening. Recent developments in tissue clearing techniques allow for imaging of whole hearts at the cellular scale, whereas magnetic resonance imaging (MRI) and computed tomography (CT) can image the myocardium at the mesoscale (100 µm to 1 mm) to resolve cardiomyocyte orientation and organization. Through histology, cardiac diffusion tensor imaging (DTI), and other modalities, mesostructural sheetlets have been confirmed in both animal and human hearts. Recent in vivo cardiac DTI methods have measured reorientation of sheetlets during the cardiac cycle. We also examine the role of pathological cardiac remodeling on sheetlet organization and reorientation, and the impact this has on ventricular function and dysfunction. We also review the unresolved mesostructural questions and challenges that may direct future work in the field.
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Affiliation(s)
- Alexander J Wilson
- Department of Radiology, Stanford University, Stanford, California
- Stanford Cardiovascular Institute, Stanford University, Stanford, California
| | - Gregory B Sands
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Ian J LeGrice
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Alistair A Young
- Department of Anatomy and Medical Imaging, University of Auckland, Auckland, New Zealand
- Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Daniel B Ennis
- Department of Radiology, Stanford University, Stanford, California
- Veterans Administration Palo Alto Health Care System, Palo Alto, California
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8
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Magat J, Yon M, Bihan-Poudec Y, Ozenne V. A groupwise registration and tractography framework for cardiac myofiber architecture description by diffusion MRI: An application to the ventricular junctions. PLoS One 2022; 17:e0271279. [PMID: 35849598 PMCID: PMC9292118 DOI: 10.1371/journal.pone.0271279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 06/27/2022] [Indexed: 11/19/2022] Open
Abstract
Background Knowledge of the normal myocardial–myocyte orientation could theoretically allow the definition of relevant quantitative biomarkers in clinical routine to diagnose heart pathologies. A whole heart diffusion tensor template representative of the global myofiber organization over species is therefore crucial for comparisons across populations. In this study, we developed a groupwise registration and tractography framework to resolve the global myofiber arrangement of large mammalian sheep hearts. To demonstrate the potential application of the proposed method, a novel description of sub-regions in the intraventricular septum is presented. Methods Three explanted sheep (ovine) hearts (size ~12×8×6 cm3, heart weight ~ 150 g) were perfused with contrast agent and fixative and imaged in a 9.4T magnet. A group-wise registration of high-resolution anatomical and diffusion-weighted images were performed to generate anatomical and diffusion tensor templates. Diffusion tensor metrics (eigenvalues, eigenvectors, fractional anisotropy …) were computed to provide a quantitative and spatially-resolved analysis of cardiac microstructure. Then tractography was performed using deterministic and probabilistic algorithms and used for different purposes: i) Visualization of myofiber architecture, ii) Segmentation of sub-area depicting the same fiber organization, iii) Seeding and Tract Editing. Finally, dissection was performed to confirm the existence of macroscopic structures identified in the diffusion tensor template. Results The template creation takes advantage of high-resolution anatomical and diffusion-weighted images obtained at an isotropic resolution of 150 μm and 600 μm respectively, covering ventricles and atria and providing information on the normal myocardial architecture. The diffusion metric distributions from the template were found close to the one of the individual samples validating the registration procedure. Small new sub-regions exhibiting spatially sharp variations in fiber orientation close to the junctions of the septum and ventricles were identified. Each substructure was defined and represented using streamlines. The existence of a fiber-bundles in the posterior junction was validated by anatomical dissection. A complex structural organization of the anterior junction in comparison to the posterior junction was evidenced by the high-resolution acquisition. Conclusions A new framework combining cardiac template generation and tractography was applied on the whole sheep heart. The framework can be used for anatomical investigation, characterization of microstructure and visualization of myofiber orientation across samples. Finally, a novel description of the ventricular junction in large mammalian sheep hearts was proposed.
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Affiliation(s)
- Julie Magat
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Univ. Bordeaux, U1045, Bordeaux, France
- INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Maxime Yon
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Univ. Bordeaux, U1045, Bordeaux, France
- INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
| | - Yann Bihan-Poudec
- Institut des Sciences Cognitives Marc Jeannerod, CNRS UMR 5229, Université Claude Bernard Lyon I, Bron, France
| | - Valéry Ozenne
- IHU Liryc, Electrophysiology and Heart Modeling Institute, Foundation Bordeaux Université, Bordeaux, France
- Centre de recherche Cardio-Thoracique de Bordeaux, Univ. Bordeaux, U1045, Bordeaux, France
- INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France
- Centre de Résonance Magnétique des Systèmes Biologiques, UMR 5536, CNRS/Université de Bordeaux, Bordeaux, France
- * E-mail:
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9
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Stimm J, Guenthner C, Kozerke S, Stoeck CT. Comparison of interpolation methods of predominant cardiomyocyte orientation from in vivo and ex vivo cardiac diffusion tensor imaging data. NMR IN BIOMEDICINE 2022; 35:e4667. [PMID: 34964179 PMCID: PMC9285076 DOI: 10.1002/nbm.4667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/25/2021] [Accepted: 11/26/2021] [Indexed: 06/14/2023]
Abstract
Cardiac electrophysiology and cardiac mechanics both depend on the average cardiomyocyte long-axis orientation. In the realm of personalized medicine, knowledge of the patient-specific changes in cardiac microstructure plays a crucial role. Patient-specific computational modelling has emerged as a tool to better understand disease progression. In vivo cardiac diffusion tensor imaging (cDTI) is a vital tool to non-destructively measure the average cardiomyocyte long-axis orientation in the heart. However, cDTI suffers from long scan times, rendering volumetric, high-resolution acquisitions challenging. Consequently, interpolation techniques are needed to populate bio-mechanical models with patient-specific average cardiomyocyte long-axis orientations. In this work, we compare five interpolation techniques applied to in vivo and ex vivo porcine input data. We compare two tensor interpolation approaches, one rule-based approximation, and two data-driven, low-rank models. We demonstrate the advantage of tensor interpolation techniques, resulting in lower interpolation errors than do low-rank models and rule-based methods adapted to cDTI data. In an ex vivo comparison, we study the influence of three imaging parameters that can be traded off against acquisition time: in-plane resolution, signal to noise ratio, and number of acquired short-axis imaging slices.
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Affiliation(s)
- Johanna Stimm
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - Christian Guenthner
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - Sebastian Kozerke
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
| | - Christian T. Stoeck
- Institute for Biomedical EngineeringUniversity and ETH ZurichZurichSwitzerland
- Division of Surgical ResearchUniversity Hospital ZurichUniversity ZurichSwitzerland
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10
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Rahman T, Moulin K, Perotti LE. Cardiac Diffusion Tensor Biomarkers of Chronic Infarction Based on In Vivo Data. APPLIED SCIENCES-BASEL 2022; 12. [PMID: 36032414 PMCID: PMC9408809 DOI: 10.3390/app12073512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
In vivo cardiac diffusion tensor imaging (cDTI) data were acquired in
swine subjects six to ten weeks post-myocardial infarction (MI) to identify
microstructural-based biomarkers of MI. Diffusion tensor invariants, diffusion
tensor eigenvalues, and radial diffusivity (RD) are evaluated in the infarct,
border, and remote myocardium, and compared with extracellular volume fraction
(ECV) and native T1 values. Additionally, to aid the interpretation of the
experimental results, the diffusion of water molecules was numerically simulated
as a function of ECV. Finally, findings based on in vivo measures were confirmed
using higher-resolution and higher signal-to-noise data acquired ex vivo in the
same subjects. Mean diffusivity, diffusion tensor eigenvalues, and RD increased
in the infarct and border regions compared to remote myocardium, while
fractional anisotropy decreased. Secondary (e2) and tertiary
(e3) eigenvalues increased more significantly than the primary
eigenvalue in the infarct and border regions. These findings were confirmed by
the diffusion simulations. Although ECV presented the largest increase in
infarct and border regions, e2, e3, and RD increased the
most among non-contrast-based biomarkers. RD is of special interest as it
summarizes the changes occurring in the radial direction and may be more robust
than e2 or e3 alone.
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Affiliation(s)
- Tanjib Rahman
- Department of Mechanical and Aerospace Engineering,
University of Central Florida, Orlando, FL 32816, USA
| | - Kévin Moulin
- CREATIS Laboratory, Univ. Lyon, UJM-Saint-Etienne, INSA,
CNRS UMR 5520, INSERM, 69100 Villeurbanne, France
- Department of Radiology, University Hospital Saint-Etienne,
42270 Saint-Priest-en-Jarez, France
| | - Luigi E. Perotti
- Department of Mechanical and Aerospace Engineering,
University of Central Florida, Orlando, FL 32816, USA
- Correspondence:
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11
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Rodriguez Padilla J, Petras A, Magat J, Bayer J, Bihan-Poudec Y, El-Hamrani D, Ramlugun G, Neic A, Augustin C, Vaillant F, Constantin M, Benoist D, Pourtau L, Dubes V, Rogier J, Labrousse L, Bernus O, Quesson B, Haissaguerre M, Gsell M, Plank G, Ozenne V, Vigmond E. Impact of Intraventricular Septal Fiber Orientation on Cardiac Electromechanical Function. Am J Physiol Heart Circ Physiol 2022; 322:H936-H952. [PMID: 35302879 PMCID: PMC9109800 DOI: 10.1152/ajpheart.00050.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cardiac fiber direction is an important factor determining the propagation of electrical activity, as well as the development of mechanical force. In this article, we imaged the ventricles of several species with special attention to the intraventricular septum to determine the functional consequences of septal fiber organization. First, we identified a dual-layer organization of the fiber orientation in the intraventricular septum of ex vivo sheep hearts using diffusion tensor imaging at high field MRI. To expand the scope of the results, we investigated the presence of a similar fiber organization in five mammalian species (rat, canine, pig, sheep, and human) and highlighted the continuity of the layer with the moderator band in large mammalian species. We implemented the measured septal fiber fields in three-dimensional electromechanical computer models to assess the impact of the fiber orientation. The downward fibers produced a diamond activation pattern superficially in the right ventricle. Electromechanically, there was very little change in pressure volume loops although the stress distribution was altered. In conclusion, we clarified that the right ventricular septum has a downwardly directed superficial layer in larger mammalian species, which can have modest effects on stress distribution. NEW & NOTEWORTHY A dual-layer organization of the fiber orientation in the intraventricular septum was identified in ex vivo hearts of large mammals. The RV septum has a downwardly directed superficial layer that is continuous with the moderator band. Electrically, it produced a diamond activation pattern. Electromechanically, little change in pressure volume loops were noticed but stress distribution was altered. Fiber distribution derived from diffusion tensor imaging should be considered for an accurate strain and stress analysis.
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Affiliation(s)
| | - Argyrios Petras
- Johann Radon Institute for Computational and Applied Mathematics (RICAM), Austrian Academy of Sciences, Linz, Austria
| | - Julie Magat
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Jason Bayer
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, IMB, UMR 5251, Talence, France
| | - Yann Bihan-Poudec
- Centre de Neuroscience Cognitive, CNRS UMR 5229, Université Claude Bernard Lyon I, France
| | - Dounia El-Hamrani
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Girish Ramlugun
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Aurel Neic
- Gottfried Schatz Research Center, Division of Biophysics, Medical University of Graz, Graz, Austria
| | - Christoph Augustin
- Gottfried Schatz Research Center, Division of Biophysics, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Fanny Vaillant
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Marion Constantin
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - David Benoist
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Line Pourtau
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Virginie Dubes
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | | | | | - Olivier Bernus
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | - Bruno Quesson
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, Bordeaux, France
| | | | - Matthias Gsell
- Gottfried Schatz Research Center, Division of Biophysics, Medical University of Graz, Graz, Austria
| | - Gernot Plank
- Gottfried Schatz Research Center, Division of Biophysics, Medical University of Graz, Graz, Austria.,BioTechMed-Graz, Graz, Austria
| | - Valéry Ozenne
- Centre de Résonance Magnétique des Systèmes Biologiques, UMR 5536, CNRS/Université de Bordeaux, Bordeaux, France
| | - Edward Vigmond
- Liryc, Electrophysiology and Heart Modeling Institute, Fondation Bordeaux Université, Pessac-Bordeaux, France.,Univ. Bordeaux, IMB, UMR 5251, Talence, France
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12
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Stimm J, Nordsletten DA, Jilberto J, Miller R, Berberoğlu E, Kozerke S, Stoeck CT. Personalization of biomechanical simulations of the left ventricle by in-vivo cardiac DTI data: Impact of fiber interpolation methods. Front Physiol 2022; 13:1042537. [PMID: 36518106 PMCID: PMC9742433 DOI: 10.3389/fphys.2022.1042537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 11/14/2022] [Indexed: 11/29/2022] Open
Abstract
Simulations of cardiac electrophysiology and mechanics have been reported to be sensitive to the microstructural anisotropy of the myocardium. Consequently, a personalized representation of cardiac microstructure is a crucial component of accurate, personalized cardiac biomechanical models. In-vivo cardiac Diffusion Tensor Imaging (cDTI) is a non-invasive magnetic resonance imaging technique capable of probing the heart's microstructure. Being a rather novel technique, issues such as low resolution, signal-to noise ratio, and spatial coverage are currently limiting factors. We outline four interpolation techniques with varying degrees of data fidelity, different amounts of smoothing strength, and varying representation error to bridge the gap between the sparse in-vivo data and the model, requiring a 3D representation of microstructure across the myocardium. We provide a workflow to incorporate in-vivo myofiber orientation into a left ventricular model and demonstrate that personalized modelling based on fiber orientations from in-vivo cDTI data is feasible. The interpolation error is correlated with a trend in personalized parameters and simulated physiological parameters, strains, and ventricular twist. This trend in simulation results is consistent across material parameter settings and therefore corresponds to a bias introduced by the interpolation method. This study suggests that using a tensor interpolation approach to personalize microstructure with in-vivo cDTI data, reduces the fiber uncertainty and thereby the bias in the simulation results.
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Affiliation(s)
- Johanna Stimm
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - David A Nordsletten
- Department of Biomedical Engineering and Cardiac Surgery, University of Michigan, Ann Arbor, MI, United States.,School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Javiera Jilberto
- Department of Biomedical Engineering and Cardiac Surgery, University of Michigan, Ann Arbor, MI, United States
| | - Renee Miller
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Ezgi Berberoğlu
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Christian T Stoeck
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.,Division of Surgical Research, University Hospital Zurich, University Zurich, Zurich, Switzerland
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