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Chimura M, Ohtani T, Sera F, Higuchi R, Kajitani K, Nakajima K, Sakata Y. Novel indices representing heterogeneous distributions of myocardial perfusion imaging. Ann Nucl Med 2024; 38:468-474. [PMID: 38502462 PMCID: PMC11108922 DOI: 10.1007/s12149-024-01920-w] [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: 12/21/2023] [Accepted: 02/29/2024] [Indexed: 03/21/2024]
Abstract
INTRODUCTION Heterogeneous distribution in myocardial perfusion images (MPI) obtained by scintigraphy is often observed in cardiac diseases with normal myocardial perfusion. However, quantitative assessments of such heterogeneity have not been established. We hypothesized that the heterogeneity in MPI can be quantitatively evaluated through histogram analysis, calculating the standard deviation (SD), the 95% bandwidth (BW95%), and entropy. METHODS We examined resting 99mTc-MIBI images in 20 healthy subjects and 29 patients with cardiac disease who had none or very-mild reduced myocardial perfusion evaluated as a low summed rest score (0 to 4, the range of the studied healthy subjects). Two nuclear medicine specialists blindly divided them into two groups: non-heterogeneity or heterogeneity group, based solely on their visual assessments of heterogeneity on splash and polar maps generated from single-photon emission computed tomography (SPECT) images. The %uptake was determined by dividing the tracer count of each pixel by the tracer count of the pixel with the highest value in the LV myocardium. SD, BW95%, and entropy from histogram patterns were analyzed from the polar map data array of each %uptake. We investigated whether heterogeneity could be assessed using SD, BW95, and entropy in two groups classified by visual assessments. Additionally, we evaluated the area under the curve (AUC) to identify heterogeneity in the receiver operating characteristic curve analysis. RESULTS Based solely on visual assessments, 11 (22%) and 38 (78%) cases were classified into the non-heterogeneity and heterogeneity groups, respectively. The non-heterogeneity group consisted of only healthy subjects, and all patients with cardiac disease were classified into the heterogeneity group. The cases in the heterogeneity group had significantly higher values of heterogeneity indices (SD, BW95%, and entropy) in %uptake than those in the non-heterogeneity group (p < 0.05 for all). The AUCs of the heterogeneity indices were sufficiently high (AUCs > 0.90 for all) in distinguishing cases with visually heterogeneous distribution or patients with cardiac disease. CONCLUSIONS Heterogeneity in MPI can be evaluated using SD, BW95%, and entropy through histogram analysis. These novel indices may help identify patients with subtle myocardial changes, even in images that show preserved perfusion (345/350).
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Affiliation(s)
- Misato Chimura
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan
| | - Tomohito Ohtani
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan.
| | - Fusako Sera
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan
| | - Rie Higuchi
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan
| | - Kenji Kajitani
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan
| | - Kenichi Nakajima
- Department of Nuclear Medicine/Functional Imaging and Artificial Intelligence, Kanazawa University Graduate School of Medicine, Kanazawa, Japan
| | - Yasushi Sakata
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, 565-0871, Japan
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Hesse K, Khanji MY, Aung N, Dabbagh GS, Petersen SE, Chahal CAA. Assessing heterogeneity on cardiovascular magnetic resonance imaging: a novel approach to diagnosis and risk stratification in cardiac diseases. Eur Heart J Cardiovasc Imaging 2024; 25:437-445. [PMID: 37982176 DOI: 10.1093/ehjci/jead285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 10/13/2023] [Accepted: 10/16/2023] [Indexed: 11/21/2023] Open
Abstract
Cardiac disease affects the heart non-uniformly. Examples include focal septal or apical hypertrophy with reduced strain in hypertrophic cardiomyopathy, replacement fibrosis with akinesia in an infarct-related coronary artery territory, and a pattern of scarring in dilated cardiomyopathy. The detail and versatility of cardiovascular magnetic resonance (CMR) imaging mean it contains a wealth of information imperceptible to the naked eye and not captured by standard global measures. CMR-derived heterogeneity biomarkers could facilitate early diagnosis, better risk stratification, and a more comprehensive prediction of treatment response. Small cohort and case-control studies demonstrate the feasibility of proof-of-concept structural and functional heterogeneity measures. Detailed radiomic analyses of different CMR sequences using open-source software delineate unique voxel patterns as hallmarks of histopathological changes. Meanwhile, measures of dispersion applied to emerging CMR strain sequences describe variable longitudinal, circumferential, and radial function across the myocardium. Two of the most promising heterogeneity measures are the mean absolute deviation of regional standard deviations on native T1 and T2 and the standard deviation of time to maximum regional radial wall motion, termed the tissue synchronization index in a 16-segment left ventricle model. Real-world limitations include the non-standardization of CMR imaging protocols across different centres and the testing of large numbers of radiomic features in small, inadequately powered patient samples. We, therefore, propose a three-step roadmap to benchmark novel heterogeneity biomarkers, including defining normal reference ranges, statistical modelling against diagnosis and outcomes in large epidemiological studies, and finally, comprehensive internal and external validations.
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Affiliation(s)
- Kerrick Hesse
- Cardiology Department, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW, UK
- Centre for Advanced Cardiovascular Imaging, William Harvey Research Institute, NIHR Barts Biomedical Research Centre, Queen Mary University London, Charterhouse Square, London EC1M 6BQ, UK
| | - Mohammed Y Khanji
- Centre for Advanced Cardiovascular Imaging, William Harvey Research Institute, NIHR Barts Biomedical Research Centre, Queen Mary University London, Charterhouse Square, London EC1M 6BQ, UK
- Newham University Hospital, Barts Health NHS Trust, Geln Road, Plaistow, London E13 8SL, UK
- Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
| | - Nay Aung
- Centre for Advanced Cardiovascular Imaging, William Harvey Research Institute, NIHR Barts Biomedical Research Centre, Queen Mary University London, Charterhouse Square, London EC1M 6BQ, UK
- Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
| | - Ghaith Sharaf Dabbagh
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, MI, USA
- Center for Inherited Cardiovascular Diseases, WellSpan Health, 30 Monument Road, York, PA 17403, USA
| | - Steffen E Petersen
- Centre for Advanced Cardiovascular Imaging, William Harvey Research Institute, NIHR Barts Biomedical Research Centre, Queen Mary University London, Charterhouse Square, London EC1M 6BQ, UK
- Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
- Health Data Research UK, Gibbs Building, 215 Euston Road, London NW1 2BE, UK
- Alan Turing Institute, 96 Euston Road, London NW1 2DB, UK
| | - C Anwar A Chahal
- Barts Heart Centre, Barts Health NHS Trust, St Bartholomew's Hospital, West Smithfield, London EC1A 7BE, UK
- Center for Inherited Cardiovascular Diseases, WellSpan Health, 30 Monument Road, York, PA 17403, USA
- Department of Cardiovascular Medicine, Mayo Clinic, 200 First Str, SW Rochester, MN 55905, USA
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Morales MA, Snel GJH, van den Boomen M, Borra RJH, van Deursen VM, Slart RHJA, Izquierdo-Garcia D, Prakken NHJ, Catana C. DeepStrain Evidence of Asymptomatic Left Ventricular Diastolic and Systolic Dysfunction in Young Adults With Cardiac Risk Factors. Front Cardiovasc Med 2022; 9:831080. [PMID: 35479280 PMCID: PMC9035693 DOI: 10.3389/fcvm.2022.831080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 03/11/2022] [Indexed: 11/17/2022] Open
Abstract
Purpose To evaluate if a fully-automatic deep learning method for myocardial strain analysis based on magnetic resonance imaging (MRI) cine images can detect asymptomatic dysfunction in young adults with cardiac risk factors. Methods An automated workflow termed DeepStrain was implemented using two U-Net models for segmentation and motion tracking. DeepStrain was trained and tested using short-axis cine-MRI images from healthy subjects and patients with cardiac disease. Subsequently, subjects aged 18–45 years were prospectively recruited and classified among age- and gender-matched groups: risk factor group (RFG) 1 including overweight without hypertension or type 2 diabetes; RFG2 including hypertension without type 2 diabetes, regardless of overweight; RFG3 including type 2 diabetes, regardless of overweight or hypertension. Subjects underwent cardiac short-axis cine-MRI image acquisition. Differences in DeepStrain-based left ventricular global circumferential and radial strain and strain rate among groups were evaluated. Results The cohort consisted of 119 participants: 30 controls, 39 in RFG1, 30 in RFG2, and 20 in RFG3. Despite comparable (>0.05) left-ventricular mass, volumes, and ejection fraction, all groups (RFG1, RFG2, RFG3) showed signs of asymptomatic left ventricular diastolic and systolic dysfunction, evidenced by lower circumferential early-diastolic strain rate (<0.05, <0.001, <0.01), and lower septal circumferential end-systolic strain (<0.001, <0.05, <0.001) compared with controls. Multivariate linear regression showed that body surface area correlated negatively with all strain measures (<0.01), and mean arterial pressure correlated negatively with early-diastolic strain rate (<0.01). Conclusion DeepStrain fully-automatically provided evidence of asymptomatic left ventricular diastolic and systolic dysfunction in asymptomatic young adults with overweight, hypertension, and type 2 diabetes risk factors.
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Affiliation(s)
- Manuel A. Morales
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States
- *Correspondence: Manuel A. Morales
| | - Gert J. H. Snel
- Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Maaike van den Boomen
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Cardiovascular Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
| | - Ronald J. H. Borra
- Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Nuclear Medicine and Molecular Imaging, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Vincent M. van Deursen
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Riemer H. J. A. Slart
- Department of Nuclear Medicine and Molecular Imaging, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Department of Biomedical Photonic Imaging, Faculty of Science and Technology, University of Twente, Enschede, Netherlands
| | - David Izquierdo-Garcia
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, United States
| | - Niek H. J. Prakken
- Department of Radiology, Medical Imaging Center, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Ciprian Catana
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Ciprian Catana
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4
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Berberoğlu E, Stoeck CT, Moireau P, Kozerke S, Genet M. In-silico study of accuracy and precision of left-ventricular strain quantification from 3D tagged MRI. PLoS One 2021; 16:e0258965. [PMID: 34739495 PMCID: PMC8570486 DOI: 10.1371/journal.pone.0258965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 10/08/2021] [Indexed: 11/18/2022] Open
Abstract
Cardiac Magnetic Resonance Imaging (MRI) allows quantifying myocardial tissue deformation and strain based on the tagging principle. In this work, we investigate accuracy and precision of strain quantification from synthetic 3D tagged MRI using equilibrated warping. To this end, synthetic biomechanical left-ventricular tagged MRI data with varying tag distance, spatial resolution and signal-to-noise ratio (SNR) were generated and processed to quantify errors in radial, circumferential and longitudinal strains relative to ground truth. Results reveal that radial strain is more sensitive to image resolution and noise than the other strain components. The study also shows robustness of quantifying circumferential and longitudinal strain in the presence of geometrical inconsistencies of 3D tagged data. In conclusion, our study points to the need for higher-resolution 3D tagged MRI than currently available in practice in order to achieve sufficient accuracy of radial strain quantification.
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Affiliation(s)
- Ezgi Berberoğlu
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Christian T. Stoeck
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Philippe Moireau
- MΞDISIM team, Inria, Palaiseau, France
- Laboratoire de Mécanique des Solides (LMS), École Polytechnique, C.N.R.S., Institut Polytechnique de Paris, Palaiseau, France
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Martin Genet
- MΞDISIM team, Inria, Palaiseau, France
- Laboratoire de Mécanique des Solides (LMS), École Polytechnique, C.N.R.S., Institut Polytechnique de Paris, Palaiseau, France
- * E-mail:
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Soon K, Mourad O, Nunes SS. Engineered human cardiac microtissues: The state-of-the-(he)art. STEM CELLS (DAYTON, OHIO) 2021; 39:1008-1016. [PMID: 33786918 DOI: 10.1002/stem.3376] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/05/2021] [Indexed: 11/06/2022]
Abstract
Due to the integration of recent advances in stem cell biology, materials science, and engineering, the field of cardiac tissue engineering has been rapidly progressing toward developing more accurate functional 3D cardiac microtissues from human cell sources. These engineered tissues enable screening of cardiotoxic drugs, disease modeling (eg, by using cells from specific genetic backgrounds or modifying environmental conditions) and can serve as novel drug development platforms. This concise review presents the most recent advances and improvements in cardiac tissue formation, including cardiomyocyte maturation and disease modeling.
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Affiliation(s)
- Kayla Soon
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Omar Mourad
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Sara S Nunes
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Heart & Stroke/Richard Lewar Centre of Excellence, University of Toronto, Toronto, Ontario, Canada
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6
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Miura M, Handoh T, Taguchi Y, Hasegawa T, Takahashi Y, Morita N, Matsumoto A, Shindoh C, Sato H. Transient Elevation of Glucose Increases Arrhythmia Susceptibility in Non-Diabetic Rat Trabeculae With Non-Uniform Contraction. Circ J 2020; 84:551-558. [PMID: 32092718 DOI: 10.1253/circj.cj-19-0715] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND In non-diabetic patients with acute coronary syndrome, stress hyperglycemia occasionally occurs and is related to their mortality. Whether transient elevation of glucose affects arrhythmia susceptibility in non-diabetic hearts with non-uniform contraction was examined.Methods and Results:Force, intracellular Ca2+([Ca2+]i), and membrane potential were measured in trabeculae from rat hearts. Non-uniform contraction was produced by a jet of paralyzing solution. Ca2+waves and arrhythmias were induced by electrical stimulation (2.0 mmol/L [Ca2+]o). The activity of Ca2+/calmodulin-dependent protein kinaseII (CaMKII) was measured. An elevation of glucose from 150 to 400 mg/dL increased the velocity of Ca2+waves and the number of spontaneous action potentials triggered by electrical stimulation. Besides, the elevation of glucose increased the CaMKII activity. In the presence of 1 μmol/L KN-93, the elevation of glucose did not increase the velocity of Ca2+waves and the number of triggered action potentials. In addition, in the presence of 1 μmol/L autocamtide-2 related inhibitory peptide or 50 μmol/L diazo-5-oxonorleucine, the elevation of glucose did not increase the number of triggered action potentials. Furthermore, the elevation of glucose by adding L-glucose did not increase their number. CONCLUSIONS In non-diabetic hearts with non-uniform contraction, transient elevation of glucose increases the velocity of Ca2+waves by activating CaMKII,probably through glycosylation with O-linked β-N-acetylglucosamine, thereby increasing arrhythmia susceptibility.
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Affiliation(s)
- Masahito Miura
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Tetsuya Handoh
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Yuhto Taguchi
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Taiki Hasegawa
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Yui Takahashi
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Natsuki Morita
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Ayana Matsumoto
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Chiyohiko Shindoh
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
| | - Haruka Sato
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine
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7
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Regional Myocardial Strain and Function: From Novel Techniques to Clinical Applications. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/978-1-4939-8841-9_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
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8
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Regional increase in ROS within stretched region exacerbates arrhythmias in rat trabeculae with nonuniform contraction. Pflugers Arch 2018; 470:1349-1357. [DOI: 10.1007/s00424-018-2152-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/28/2018] [Accepted: 05/01/2018] [Indexed: 12/29/2022]
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9
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Crossman DJ, Jayasinghe ID, Soeller C. Transverse tubule remodelling: a cellular pathology driven by both sides of the plasmalemma? Biophys Rev 2017; 9:919-929. [PMID: 28695473 DOI: 10.1007/s12551-017-0273-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 06/06/2017] [Indexed: 01/10/2023] Open
Abstract
Transverse (t)-tubules are invaginations of the plasma membrane that form a complex network of ducts, 200-400 nm in diameter depending on the animal species, that penetrates deep within the cardiac myocyte, where they facilitate a fast and synchronous contraction across the entire cell volume. There is now a large body of evidence in animal models and humans demonstrating that pathological distortion of the t-tubule structure has a causative role in the loss of myocyte contractility that underpins many forms of heart failure. Investigations into the molecular mechanisms of pathological t-tubule remodelling to date have focused on proteins residing in the intracellular aspect of t-tubule membrane that form linkages between the membrane and myocyte cytoskeleton. In this review, we shed light on the mechanisms of t-tubule remodelling which are not limited to the intracellular side. Our recent data have demonstrated that collagen is an integral part of the t-tubule network and that it increases within the tubules in heart failure, suggesting that a fibrotic mechanism could drive cardiac junctional remodelling. We examine the evidence that the linkages between the extracellular matrix, t-tubule membrane and cellular cytoskeleton should be considered as a whole when investigating the mechanisms of t-tubule pathology in the failing heart.
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Affiliation(s)
- David J Crossman
- Department of Physiology, University of Auckland, Auckland, New Zealand.
| | | | - Christian Soeller
- Department of Physiology, University of Auckland, Auckland, New Zealand
- Biomedical Physics, University of Exeter, Exeter, UK
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Schönleitner P, Schotten U, Antoons G. Mechanosensitivity of microdomain calcium signalling in the heart. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017. [PMID: 28648626 DOI: 10.1016/j.pbiomolbio.2017.06.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In cardiac myocytes, calcium (Ca2+) signalling is tightly controlled in dedicated microdomains. At the dyad, i.e. the narrow cleft between t-tubules and junctional sarcoplasmic reticulum (SR), many signalling pathways combine to control Ca2+-induced Ca2+ release during contraction. Local Ca2+ gradients also exist in regions where SR and mitochondria are in close contact to regulate energetic demands. Loss of microdomain structures, or dysregulation of local Ca2+ fluxes in cardiac disease, is often associated with oxidative stress, contractile dysfunction and arrhythmias. Ca2+ signalling at these microdomains is highly mechanosensitive. Recent work has demonstrated that increasing mechanical load triggers rapid local Ca2+ releases that are not reflected by changes in global Ca2+. Key mechanisms involve rapid mechanotransduction with reactive oxygen species or nitric oxide as primary signalling molecules targeting SR or mitochondria microdomains depending on the nature of the mechanical stimulus. This review summarizes the most recent insights in rapid Ca2+ microdomain mechanosensitivity and re-evaluates its (patho)physiological significance in the context of historical data on the macroscopic role of Ca2+ in acute force adaptation and mechanically-induced arrhythmias. We distinguish between preload and afterload mediated effects on local Ca2+ release, and highlight differences between atrial and ventricular myocytes. Finally, we provide an outlook for further investigation in chronic models of abnormal mechanics (eg post-myocardial infarction, atrial fibrillation), to identify the clinical significance of disturbed Ca2+ mechanosensitivity for arrhythmogenesis.
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Affiliation(s)
- Patrick Schönleitner
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands
| | - Uli Schotten
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands
| | - Gudrun Antoons
- Dept of Physiology, Cardiovascular Research Institute Maastricht, Maastricht University, The Netherlands.
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11
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Chen-Izu Y, Izu LT. Mechano-chemo-transduction in cardiac myocytes. J Physiol 2017; 595:3949-3958. [PMID: 28098356 DOI: 10.1113/jp273101] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/15/2016] [Indexed: 12/31/2022] Open
Abstract
The heart has the ability to adjust to changing mechanical loads. The Frank-Starling law and the Anrep effect describe exquisite intrinsic mechanisms the heart has for autoregulating the force of contraction to maintain cardiac output under changes of preload and afterload. Although these mechanisms have been known for more than a century, their cellular and molecular underpinnings are still debated. How does the cardiac myocyte sense changes in preload or afterload? How does the myocyte adjust its response to compensate for such changes? In cardiac myocytes Ca2+ is a crucial regulator of contractile force and in this review we compare and contrast recent studies from different labs that address these two important questions. The 'dimensionality' of the mechanical milieu under which experiments are carried out provide important clues to the location of the mechanosensors and the kinds of mechanical forces they can sense and respond to. As a first approximation, sensors inside the myocyte appear to modulate reactive oxygen species while sensors on the cell surface appear to also modulate nitric oxide signalling; both signalling pathways affect Ca2+ handling. Undoubtedly, further studies will add layers to this simplified picture. Clarifying the intimate links from cellular mechanics to reactive oxygen species and nitric oxide signalling and to Ca2+ handling will deepen our understanding of the Frank-Starling law and the Anrep effect, and also provide a unified view on how arrhythmias may arise in seemingly disparate diseases that have in common altered myocyte mechanics.
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Affiliation(s)
- Ye Chen-Izu
- Department of Pharmacology, University of California, Davis, CA, 95616, USA.,Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA.,Department of Internal Medicine/Division of Cardiology, University of California, Davis, CA, 95616, USA
| | - Leighton T Izu
- Department of Pharmacology, University of California, Davis, CA, 95616, USA
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12
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Neonatal dilated cardiomyopathy. Rev Port Cardiol 2017; 36:201-214. [DOI: 10.1016/j.repc.2016.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 09/25/2016] [Accepted: 10/06/2016] [Indexed: 01/09/2023] Open
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13
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Neonatal dilated cardiomyopathy. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2017. [DOI: 10.1016/j.repce.2016.10.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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14
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Lalude OO, Lerakis S. Cardiovascular Magnetic Resonance Imaging. Interv Cardiol 2016. [DOI: 10.1002/9781118983652.ch10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
| | - Stamatios Lerakis
- Emory University School of Medicine and Georgia Institute of Technology; Atlanta GA USA
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15
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Kar J, Cupps B, Zhong X, Koerner D, Kulshrestha K, Neudecker S, Bell J, Craddock H, Pasque M. Preliminary investigation of multiparametric strain Z-score (MPZS) computation using displacement encoding with simulated echoes (DENSE) and radial point interpretation method (RPIM). J Magn Reson Imaging 2016; 44:993-1002. [PMID: 27038246 PMCID: PMC5028227 DOI: 10.1002/jmri.25239] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 02/28/2016] [Accepted: 02/29/2016] [Indexed: 01/19/2023] Open
Abstract
PURPOSE To describe and assess an automated normalization method for identifying sentinel (septal) regions of myocardial dysfunction in nonischemic, nonvalvular dilated cardiomyopathy (DCM), using an unprecedented combination of the navigator-gated 3D spiral displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI), radial point interpolation (RPIM) and multiparametric strain z-score (MPZS). MATERIALS AND METHODS Navigator-gated 3D spiral DENSE, in a 1.5T MRI machine, was used for acquiring the displacement encoded complex images, MR Analytical Software System (MASS) for automated boundary detection and automated meshfree RPIM for left-ventricular (LV) myocardial strain computation to analyze MPZS in 36 subjects (with n = 17 DCM patients). Pearson's r correlation established relations between global/sentinel MPZS and ejection fraction (EF). The time taken for combined RPIM-MPZS computations was recorded. RESULTS Maximum MPZS differences were seen between anteroseptal and posterolateral regions in the base (2.0 ± 0.3 vs. 0.9 ± 0.5) and the mid-wall (2.1 ± 0.4 vs. 1.0 ± 0.4). These regional differences were found to be consistent with historically documented septal injury in nonischemic DCM. Correlations were 0.6 between global MPZS and EF, and 0.7 between sentinel MPZS and EF. The time taken for combined RPIM-MPZS computations per subject was 18.9 ± 5.9 seconds. CONCLUSION Heterogeneous contractility found in the sentinel regions with the current automated MPZS computation scheme and the correlation found between MPZS and EF may lead to the creation of a new clinical metric in LV DCM surveillance. J. MAGN. RESON. IMAGING 2016;44:993-1002.
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MESH Headings
- Aged
- Algorithms
- Cardiomyopathy, Dilated/complications
- Cardiomyopathy, Dilated/diagnostic imaging
- Cardiomyopathy, Dilated/physiopathology
- Computer Simulation
- Elastic Modulus
- Elasticity Imaging Techniques/methods
- Female
- Humans
- Image Enhancement/methods
- Image Interpretation, Computer-Assisted/methods
- Imaging, Three-Dimensional/methods
- Magnetic Resonance Imaging/methods
- Male
- Middle Aged
- Models, Cardiovascular
- Pattern Recognition, Automated/methods
- Pilot Projects
- Reproducibility of Results
- Sensitivity and Specificity
- Signal Processing, Computer-Assisted
- Stress, Mechanical
- Stroke Volume
- Tensile Strength
- Ventricular Dysfunction, Left/diagnostic imaging
- Ventricular Dysfunction, Left/etiology
- Ventricular Dysfunction, Left/physiopathology
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Affiliation(s)
- Julia Kar
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA.
| | - Brian Cupps
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Xiaodong Zhong
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Danielle Koerner
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Kevin Kulshrestha
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Samuel Neudecker
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Jennifer Bell
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Heidi Craddock
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
| | - Michael Pasque
- Department of Surgery, School of Medicine, Washington University, St. Louis, Missouri, USA
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Hadjicharalambous M, Asner L, Chabiniok R, Sammut E, Wong J, Peressutti D, Kerfoot E, King A, Lee J, Razavi R, Smith N, Carr-White G, Nordsletten D. Non-invasive Model-Based Assessment of Passive Left-Ventricular Myocardial Stiffness in Healthy Subjects and in Patients with Non-ischemic Dilated Cardiomyopathy. Ann Biomed Eng 2016. [PMID: 27605213 DOI: 10.1007/s10439‐016‐1721‐4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Patient-specific modelling has emerged as a tool for studying heart function, demonstrating the potential to provide non-invasive estimates of tissue passive stiffness. However, reliable use of model-derived stiffness requires sufficient model accuracy and unique estimation of model parameters. In this paper we present personalised models of cardiac mechanics, focusing on improving model accuracy, while ensuring unique parametrisation. The influence of principal model uncertainties on accuracy and parameter identifiability was systematically assessed in a group of patients with dilated cardiomyopathy ([Formula: see text]) and healthy volunteers ([Formula: see text]). For all cases, we examined three circumferentially symmetric fibre distributions and two epicardial boundary conditions. Our results demonstrated the ability of data-derived boundary conditions to improve model accuracy and highlighted the influence of the assumed fibre distribution on both model fidelity and stiffness estimates. The model personalisation pipeline-based strictly on non-invasive data-produced unique parameter estimates and satisfactory model errors for all cases, supporting the selected model assumptions. The thorough analysis performed enabled the comparison of passive parameters between volunteers and dilated cardiomyopathy patients, illustrating elevated stiffness in diseased hearts.
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Affiliation(s)
- Myrianthi Hadjicharalambous
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.
| | - Liya Asner
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Radomir Chabiniok
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.,Inria and Paris-Saclay University, Bâtiment Alan Turing, 1 rue Honoré d'Estienne d'Orves, Campus de l'Ecole Polytechnique, 91120, Palaiseau, France
| | - Eva Sammut
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - James Wong
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Devis Peressutti
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Eric Kerfoot
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Andrew King
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Jack Lee
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Reza Razavi
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Nicolas Smith
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.,Department of Engineering Science, University of Auckland, 20 Symonds St, Auckland, 1010, New Zealand
| | - Gerald Carr-White
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - David Nordsletten
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
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Hadjicharalambous M, Asner L, Chabiniok R, Sammut E, Wong J, Peressutti D, Kerfoot E, King A, Lee J, Razavi R, Smith N, Carr-White G, Nordsletten D. Non-invasive Model-Based Assessment of Passive Left-Ventricular Myocardial Stiffness in Healthy Subjects and in Patients with Non-ischemic Dilated Cardiomyopathy. Ann Biomed Eng 2016; 45:605-618. [PMID: 27605213 PMCID: PMC5479360 DOI: 10.1007/s10439-016-1721-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 08/24/2016] [Indexed: 11/29/2022]
Abstract
Patient-specific modelling has emerged as a tool for studying heart function, demonstrating the potential to provide non-invasive estimates of tissue passive stiffness. However, reliable use of model-derived stiffness requires sufficient model accuracy and unique estimation of model parameters. In this paper we present personalised models of cardiac mechanics, focusing on improving model accuracy, while ensuring unique parametrisation. The influence of principal model uncertainties on accuracy and parameter identifiability was systematically assessed in a group of patients with dilated cardiomyopathy (\documentclass[12pt]{minimal}
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\begin{document}$$n=3$$\end{document}n=3) and healthy volunteers (\documentclass[12pt]{minimal}
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\begin{document}$$n=5$$\end{document}n=5). For all cases, we examined three circumferentially symmetric fibre distributions and two epicardial boundary conditions. Our results demonstrated the ability of data-derived boundary conditions to improve model accuracy and highlighted the influence of the assumed fibre distribution on both model fidelity and stiffness estimates. The model personalisation pipeline—based strictly on non-invasive data—produced unique parameter estimates and satisfactory model errors for all cases, supporting the selected model assumptions. The thorough analysis performed enabled the comparison of passive parameters between volunteers and dilated cardiomyopathy patients, illustrating elevated stiffness in diseased hearts.
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Affiliation(s)
- Myrianthi Hadjicharalambous
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.
| | - Liya Asner
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Radomir Chabiniok
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.,Inria and Paris-Saclay University, Bâtiment Alan Turing, 1 rue Honoré d'Estienne d'Orves, Campus de l'Ecole Polytechnique, 91120, Palaiseau, France
| | - Eva Sammut
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - James Wong
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Devis Peressutti
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Eric Kerfoot
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Andrew King
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Jack Lee
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Reza Razavi
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - Nicolas Smith
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK.,Department of Engineering Science, University of Auckland, 20 Symonds St, Auckland, 1010, New Zealand
| | - Gerald Carr-White
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
| | - David Nordsletten
- Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas' Hospital, London, SE1 7EH, UK
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Beta-Adrenoceptor Stimulation Reveals Ca2+ Waves and Sarcoplasmic Reticulum Ca2+ Depletion in Left Ventricular Cardiomyocytes from Post-Infarction Rats with and without Heart Failure. PLoS One 2016; 11:e0153887. [PMID: 27096943 PMCID: PMC4838269 DOI: 10.1371/journal.pone.0153887] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 04/05/2016] [Indexed: 11/25/2022] Open
Abstract
Abnormal cellular Ca2+ handling contributes to both contractile dysfunction and arrhythmias in heart failure. Reduced Ca2+ transient amplitude due to decreased sarcoplasmic reticulum Ca2+ content is a common finding in heart failure models. However, heart failure models also show increased propensity for diastolic Ca2+ release events which occur when sarcoplasmic reticulum Ca2+ content exceeds a certain threshold level. Such Ca2+ release events can initiate arrhythmias. In this study we aimed to investigate if both of these aspects of altered Ca2+ homeostasis could be found in left ventricular cardiomyocytes from rats with different states of cardiac function six weeks after myocardial infarction when compared to sham-operated controls. Video edge-detection, whole-cell Ca2+ imaging and confocal line-scan imaging were used to investigate cardiomyocyte contractile properties, Ca2+ transients and Ca2+ waves. In baseline conditions, i.e. without beta-adrenoceptor stimulation, cardiomyocytes from rats with large myocardial infarction, but without heart failure, did not differ from sham-operated animals in any of these aspects of cellular function. However, when exposed to beta-adrenoceptor stimulation, cardiomyocytes from both non-failing and failing rat hearts showed decreased sarcoplasmic reticulum Ca2+ content, decreased Ca2+ transient amplitude, and increased frequency of Ca2+ waves. These results are in line with a decreased threshold for diastolic Ca2+ release established by other studies. In the present study, factors that might contribute to a lower threshold for diastolic Ca2+ release were increased THR286 phosphorylation of Ca2+/calmodulin-dependent protein kinase II and increased protein phosphatase 1 abundance. In conclusion, this study demonstrates both decreased sarcoplasmic reticulum Ca2+ content and increased propensity for diastolic Ca2+ release events in ventricular cardiomyocytes from rats with heart failure after myocardial infarction, and that these phenomena are also found in rats with large myocardial infarctions without heart failure development. Importantly, beta-adrenoceptor stimulation is necessary to reveal these perturbations in Ca2+ handling after a myocardial infarction.
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19
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Dilated Cardiomyopathy: Normalized Multiparametric Myocardial Strain Predicts Contractile Recovery. Ann Thorac Surg 2015; 100:1284-91. [PMID: 26228597 DOI: 10.1016/j.athoracsur.2015.04.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/30/2015] [Accepted: 04/01/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND Left ventricular contractile injury in dilated cardiomyopathy (DCM) may occur in a consistently heterogeneous distribution, suggesting that early-injury sentinel regions may have prognostic significance. Heightened surveillance of these regions with high-resolution contractile metrics may predict recovery in DCM. METHODS Multiple three-dimensional strain parameters were calculated at each of 15,300 left ventricular grid points from systolic displacement data obtained from cardiac magnetic resonance imaging in 124 test subjects. In 24 DCM patients, Z-scores for two strain parameters at each grid point were calculated by comparison of patient-specific strain values to respective point-specific mean and standard deviation values from a normal human strain database (n = 100). Multiparametric strain Z-scores were averaged over six left ventricular regions at basilar, mid, and apical levels (18 subregions). Patients with DCM were stratified into three groups on the basis of a blinded review of clinical contractile recovery (complete, n = 7; incomplete, n = 7; none, n = 10). RESULTS Basilar-septal subregions were consistently heavily injured. Basilar-septal Z-scores were significantly larger (worse) than those for the rest of the left ventricle (2.73 ± 1.27 versus 2.22 ± 0.83; p = 0.011) and lateral wall (2.73 ± 1.27 versus 1.44 ± 0.72; p < 0.001). All patients with sentinel region average multiparametric strain Z-scores less than two standard deviations (n = 6) experienced complete recovery, whereas 17 of 18 DCM patients with Z-scores greater than two standard deviations experienced incomplete or no contractile recovery. CONCLUSIONS Contractile injury in DCM is heterogeneous, with basilar-septal regions injured more than lateral regions. The targeting of early-injury sentinel regions for heightened surveillance with high-resolution metrics of microregional contractile function may accurately predict recovery on medical therapy. A two standard deviation Z-score threshold may predict contractile recovery.
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20
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Henn MC, Cupps BP, Kar J, Kulshrestha K, Koerner D, Braverman AC, Pasque MK. Quantifying "normalized" regional left ventricular contractile function in ischemic coronary artery disease. J Thorac Cardiovasc Surg 2015; 150:240-6. [PMID: 25940418 PMCID: PMC4490013 DOI: 10.1016/j.jtcvs.2015.03.049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 03/18/2015] [Accepted: 03/30/2015] [Indexed: 11/21/2022]
Abstract
OBJECTIVE When significant coronary lesions are identified by angiography, regional left ventricular (LV) contractile function often plays a role in determining candidacy for revascularization. To improve on current subjective and nonquantitative metrics of regional LV function, we tested a z-score "normalization" of regional strain information quantified from clinically acquired high-resolution LV geometric datasets. METHODS Test subjects (n = 120) underwent cardiac MRI with multiple 3-dimensional strain parameters calculated from tissue tag-plane displacement data. Sixty healthy volunteers contributed strain parameter data at each of 15,300 LV grid points, to form a normal human strain database. Point-specific database comparisons were made in 60 patients who had documented coronary artery disease (CAD), by angiography. Patient-specific, color-coded 3-dimensional LV maps of z-score-normalized contractile function were generated. RESULTS Blinded clinical review indicated that 55% (33 of 60) of the patients with CAD had significant regional contractile abnormalities by 1 of 3 "gold-standard" criteria: (1) Q waves on electrocardiography (ECG); (2) infarct on radionuclide single-photon emission computed tomography (SPECT); or (3) akinesia or dyskinesia on echocardiography. Consistency among all gold-standard metrics was found for only 19% (6 of 31) of patients with CAD who had ≥2 available metrics. Blinded MRI-based, multiparametric, strain z-score localization of contractile abnormalities was accurate in 89% (ECG), 97% (SPECT), and 95% (echocardiography). CONCLUSIONS Nonsubjective normalization of regional LV contractile function by z-score calculation from a normal human strain database can localize and quantitatively display regional wall motion abnormalities in patients with CAD. This high-resolution localization of regional wall motion abnormalities may help improve the accuracy of therapeutic intervention in patients who have CAD.
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Affiliation(s)
- Matthew C Henn
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo
| | - Brian P Cupps
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo
| | - Julia Kar
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo
| | - Kevin Kulshrestha
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo
| | - Danielle Koerner
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo
| | - Alan C Braverman
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St Louis, Mo
| | - Michael K Pasque
- Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, Mo.
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Jackson T, Claridge S, Behar J, Sammut E, Webb J, Carr-White G, Razavi R, Rinaldi CA. Narrow QRS systolic heart failure: is there a target for cardiac resynchronization? Expert Rev Cardiovasc Ther 2015; 13:783-97. [PMID: 26048215 DOI: 10.1586/14779072.2015.1049945] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cardiac resynchronization therapy has revolutionized the management of systolic heart failure in patients with prolonged QRS during the past 20 years. Initially, the use of this treatment in patients with shorter QRS durations showed promising results, which have since been opposed by larger randomized controlled trials. Despite this, some questions remain, such as, whether correction of mechanical dyssynchrony is the therapeutic target by which biventricular pacing may confer benefit in this group, or are there other mechanisms that need consideration? In addition, novel techniques of cardiac resynchronization therapy delivery such as endocardial and multisite pacing may reduce potential detrimental effects of biventricular pacing, thereby improving the benefit/harm balance of this therapy in some patients.
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Affiliation(s)
- Tom Jackson
- Department of Cardiovascular Imaging, 4th Floor Lambeth Wing, St Thomas' Hospital, London, SE1 7EH, UK
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Measuring the metrics: Correlating t-tubule structure and muscle contraction in the intact heart. J Mol Cell Cardiol 2015; 85:153-4. [PMID: 26031703 DOI: 10.1016/j.yjmcc.2015.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 05/22/2015] [Indexed: 11/20/2022]
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Crossman DJ, Young AA, Ruygrok PN, Nason GP, Baddelely D, Soeller C, Cannell MB. T-tubule disease: Relationship between t-tubule organization and regional contractile performance in human dilated cardiomyopathy. J Mol Cell Cardiol 2015; 84:170-8. [PMID: 25953258 DOI: 10.1016/j.yjmcc.2015.04.022] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 04/27/2015] [Accepted: 04/28/2015] [Indexed: 11/30/2022]
Abstract
Evidence from animal models suggest that t-tubule changes may play an important role in the contractile deficit associated with heart failure. However samples are usually taken at random with no regard as to regional variability present in failing hearts which leads to uncertainty in the relationship between contractile performance and possible t-tubule derangement. Regional contraction in human hearts was measured by tagged cine MRI and model fitting. At transplant, failing hearts were biopsy sampled in identified regions and immunocytochemistry was used to label t-tubules and sarcomeric z-lines. Computer image analysis was used to assess 5 different unbiased measures of t-tubule structure/organization. In regions of failing hearts that showed good contractile performance, t-tubule organization was similar to that seen in normal hearts, with worsening structure correlating with the loss of regional contractile performance. Statistical analysis showed that t-tubule direction was most highly correlated with local contractile performance, followed by the amplitude of the sarcomeric peak in the Fourier transform of the t-tubule image. Other area based measures were less well correlated. We conclude that regional contractile performance in failing human hearts is strongly correlated with the local t-tubule organization. Cluster tree analysis with a functional definition of failing contraction strength allowed a pathological definition of 't-tubule disease'. The regional variability in contractile performance and cellular structure is a confounding issue for analysis of samples taken from failing human hearts, although this may be overcome with regional analysis by using tagged cMRI and biopsy mapping.
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Affiliation(s)
| | - Alistair A Young
- Department of Anatomy with Radiology, University of Auckland, New Zealand
| | - Peter N Ruygrok
- Department of Cardiology, Auckland City Hospital, New Zealand
| | - Guy P Nason
- School of Mathematics, University of Bristol, UK
| | - David Baddelely
- Department of Physiology, University of Auckland, New Zealand
| | | | - Mark B Cannell
- Department of Physiology, University of Auckland, New Zealand; School of Physiology and Pharmacology, University of Bristol, UK.
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Jahanzad Z, Liew YM, Bilgen M, McLaughlin RA, Leong CO, Chee KH, Aziz YFA, Ung NM, Lai KW, Ng SC, Lim E. Regional assessment of LV wall in infarcted heart using tagged MRI and cardiac modelling. Phys Med Biol 2015; 60:4015-31. [DOI: 10.1088/0031-9155/60/10/4015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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Kono AK, Croisille P, Nishii T, Nishiyama K, Kyotani K, Shigeru M, Takamine S, Fujiwara S, Sugimura K. Cardiovascular magnetic resonance tagging imaging correlates with myocardial dysfunction and T2 mapping in idiopathic dilated cardiomyopathy. Int J Cardiovasc Imaging 2014; 30 Suppl 2:145-52. [DOI: 10.1007/s10554-014-0523-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 08/15/2014] [Indexed: 11/28/2022]
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26
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Alter P, Rupp H, Adams P, Stoll F, Figiel JH, Klose KJ, Rominger MB, Maisch B. Occurrence of late gadolinium enhancement is associated with increased left ventricular wall stress and mass in patients with non-ischaemic dilated cardiomyopathy. Eur J Heart Fail 2014; 13:937-44. [DOI: 10.1093/eurjhf/hfr082] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Peter Alter
- Department of Internal Medicine-Cardiology; Philipps University; Marburg Germany
| | - Heinz Rupp
- Department of Internal Medicine-Cardiology; Philipps University; Marburg Germany
| | - Philipp Adams
- Department of Internal Medicine-Cardiology; Philipps University; Marburg Germany
| | - Florian Stoll
- Department of Internal Medicine-Cardiology; Philipps University; Marburg Germany
| | - Jens H. Figiel
- Department of Radiology; Philipps University; Marburg Germany
| | - Klaus J. Klose
- Department of Radiology; Philipps University; Marburg Germany
| | | | - Bernhard Maisch
- Department of Internal Medicine-Cardiology; Philipps University; Marburg Germany
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Kar J, Knutsen AK, Cupps BP, Zhong X, Pasque MK. Three-dimensional regional strain computation method with displacement encoding with stimulated echoes (DENSE) in non-ischemic, non-valvular dilated cardiomyopathy patients and healthy subjects validated by tagged MRI. J Magn Reson Imaging 2014; 41:386-96. [PMID: 24753028 DOI: 10.1002/jmri.24576] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 01/03/2014] [Indexed: 11/11/2022] Open
Abstract
PURPOSE Fast cine displacement encoding with stimulated echoes (DENSE) MR has higher spatial resolution and enables rapid postprocessing. Thus we compared the accuracy of regional strains computation by DENSE with tagged MR in healthy and non-ischemic, non-valvular dilated cardiomyopathy (DCM) subjects. MATERIALS AND METHODS Validation of three-dimensional regional strains computed with DENSE was conducted in reference to standard tagged MRI (TMRI) in healthy subjects and patients with DCM. Additional repeatability studies in healthy subjects were conducted to increase confidence in DENSE. A meshfree multiquadrics radial point interpolation method (RPIM) was used for computing Lagrange strains in sixteen left ventricular segments. Bland-Altman analysis and Student's t-tests were conducted to observe similarities in regional strains between sequences and in DENSE repeatability studies. RESULTS Regional circumferential strains ranged from -0.21 ± 0.07 (Lateral-Apex) to -0.11 ± 0.05 (Posterorseptal-Base) in healthy subjects and -0.15 ± 0.04 (Anterior-Apex) to -0.02 ± 0.08 (Posterorseptal-Base) in DCM patients. Computed mean differences in regional circumferential strain from the DENSE-TMRI comparison study was 0.01 ± 0.03 (95% limits of agreement) in normal subjects, -0.01 ± 0.06 in DCM patients and 0.0 ± 0.02 in repeatability studies, with similar agreements in longitudinal and radial strains. CONCLUSION We found agreement between DENSE and tagged MR in patients and volunteers in terms of evaluation of regional strains.
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Affiliation(s)
- Julia Kar
- Department of Surgery School of Medicine, Washington University, St Louis, Missouri, USA
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Kubota S, Wakasa S, Shingu Y, Ooka T, Tachibana T, Matsui Y. Preoperative regional left ventricular wall thickening determined by quantitative gated SPECT as a predictor of mid-term surgical results for ischemic and nonischemic cardiomyopathy. Circ J 2013; 77:2936-41. [PMID: 23995760 DOI: 10.1253/circj.cj-13-0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND This study aimed to elucidate whether regional left ventricular wall thickening (LVWT) determined by quantitative gated SPECT (QGS) is useful in predicting surgical outcomes for ischemic (ICM) and nonischemic cardiomyopathy (NICM). METHODS AND RESULTS The study group comprised 53 patients with either ICM (n=30, left ventricular ejection fraction (LVEF)=24.7±7.1%) or NICM (n=23, LVEF=24.0±6.3%) scheduled for surgical repair underwent preoperative QGS to evaluate regional LV function. LVWT of 20 segments derived from QGS was normalized by being divided by the normal value of each LV level. Normalized values of the segments were summed to be representative of each area. For 16 of the 30 patients with ICM and 17 of the 23 patients with NICM, surgical ventricular restoration and papillary muscle approximation (PMA) were performed for surgical repair and, for the rest, PMA alone was done for both ICM and NICM patients. Adjunctive coronary artery bypass grafting for ICM patients was added when necessary. Mean follow-up periods were 2.5±1.8 years for ICM and 2.2±2.4 years for NICM. Posterior regional LVWT in NICM (normalized sum value <0.61 n=7, ROC: AUC=0.80) predicted cardiac events (chronic heart failure and cardiac-caused death). The one-year cardiac event-free rates were 22.2% and 85.1% and the 2 years rates were 11.1% and 48.6% for the lower posterior WT group and higher posterior WT group respectively (P=0.003). CONCLUSIONS Posterior LVWT can be a predictor for postoperative cardiac events in patients with NICM.
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Affiliation(s)
- Suguru Kubota
- Department of Cardiovascular Surgery, Hokkaido University Hospital
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New insights in LV torsion for the selection of cardiac resynchronisation therapy candidates. Neth Heart J 2013; 19:386-91. [PMID: 21562790 DOI: 10.1007/s12471-011-0136-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Recent literature indicates that torsion of the left ventricle (LV) is a promising predictor for response to cardiac resynchronisation therapy (CRT). Among patients with severe heart failure, 45 to 75% of patients show rigid body rotation, where the base and apex rotate in the same direction, instead of normal, opposite rotation. The occurrence of this phenomenon seems to be a good indicator for response to CRT. From this review, it can be concluded that LV torsion might be a welcome addition to current selection criteria.
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Matsumoto K, Tanaka H, Tatsumi K, Kaneko A, Tsuji T, Ryo K, Kawai H, Hirata KI. Regional Heterogeneity of Systolic Dysfunction Is Associated with Ventricular Dyssynchrony in Patients with Idiopathic Dilated Cardiomyopathy and Narrow QRS Complex. Echocardiography 2012; 29:1201-10. [DOI: 10.1111/j.1540-8175.2012.01791.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Kensuke Matsumoto
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Hidekazu Tanaka
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Kazuhiro Tatsumi
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Akihiro Kaneko
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Takayuki Tsuji
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Keiko Ryo
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Hiroya Kawai
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
| | - Ken-ichi Hirata
- Division of Cardiovascular Medicine; Department of Internal Medicine; Kobe University Graduate School of Medicine; Kobe; Japan
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Simpson RM, Keegan J, Firmin DN. MR assessment of regional myocardial mechanics. J Magn Reson Imaging 2012; 37:576-99. [PMID: 22826177 DOI: 10.1002/jmri.23756] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 06/15/2012] [Indexed: 12/30/2022] Open
Abstract
Regional myocardial function can be measured by several MR techniques including tissue tagging, phase velocity mapping, and more recently, displacement encoding with stimulated echoes (DENSE) and strain encoding (SENC). Each of these techniques was developed separately and has undergone significant change since its original implementation. As a result, in the current literature, the common features and the differences between the techniques and what they measure are often unclear and confusing. This review article delivers an extensively referenced introductory text which clarifies the current methodology from the starting point of the Bloch equations. By doing this in a consistent way for each method, the similarities and differences between them are highlighted. In addition, their capabilities and limitations are discussed, together with their relative advantages and disadvantages. While the focus is on sequence design and development, the principal parameters measured by each technique are also summarized, together with brief results, with the reader being directed to the extensive literature on data processing and clinical applications for more detail.
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Affiliation(s)
- Robin M Simpson
- Cardiovascular Magnetic Resonance Unit, Royal Brompton and Harefield NHS Hospital Trust, London, United Kingdom.
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Brady BD, Knutsen AK, Ma N, Gardner R, Taggar AK, Cupps BP, Kouchoukos NT, Pasque MK. MRI-based multiparametric strain analysis predicts contractile recovery after aortic valve replacement for aortic insufficiency. J Card Surg 2012; 27:415-22. [PMID: 22612862 DOI: 10.1111/j.1540-8191.2012.01477.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Guidelines for referral of chronic aortic insufficiency (AI) patients for aortic valve replacement (AVR) suggest that surgery can be delayed until symptoms or reduction in left ventricular (LV) contractile function occur. The frequent occurrence of reduced LV contractile function after AVR for chronic AI suggests that new contractile metrics for surgical referral are needed. METHODS In 16 chronic AI patients, cardiac MRI tagged images were analyzed before and 21.5 ± 13.8 months after AVR to calculate LV systolic strain. Average measurements of three strain parameters were obtained for each of 72 LV regions, normalized using a normal human strain database (n = 63), and combined into a composite index (multiparametric strain z score [MSZ]) representing standard deviation from the normal regional average. RESULTS Preoperative global MSZ (72-region average) correlated with post-AVR global MSZ (R(2) = 0.825, p < 0.001). Preoperative global MSZ also predicts improvement of impaired regions (N = 271 regions from 14 AI patients, R(2) = 0.392, p < 0.001). Preoperative MRI-based LV ejection fraction (LVEF) is also predictive (r = 0.410, p < 0.001). Although global preoperative MSZ had a significantly higher correlation than preoperative LVEF with improvement of injured regions (p < 0.001), both measures convey the same phenomenon. CONCLUSIONS Global preoperative MRI-based multiparametric strain predicts global strain postoperatively, as well as improvement of regions (n = 72 per LV) with impaired contractile function. Global contractile function is an important correlate with improvement in regionally impaired contractile function, perhaps reflecting total AI volume-overload burden (severity/duration of AI).
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Affiliation(s)
- Beckah D Brady
- Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
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Knutsen AK, Ma N, Taggar AK, Brady BD, Cupps BP, Pasque MK. Heterogeneous distribution of left ventricular contractile injury in chronic aortic insufficiency. Ann Thorac Surg 2012; 93:1121-7. [PMID: 22381452 DOI: 10.1016/j.athoracsur.2011.12.067] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 12/22/2011] [Accepted: 12/28/2011] [Indexed: 11/26/2022]
Abstract
BACKGROUND Global systolic strain has been described previously in patients with chronic aortic insufficiency (AI). This study explored regional differences in contractile injury. METHODS Tagged magnetic resonance images of the left ventricle (LV) were acquired and analyzed to calculate systolic strain in 42 patients with chronic AI. Multiparametric systolic strain analysis was applied to relate cardiac function in AI patients to a normal strain database (N = 60). AI patients were classified as having normal or poor function based on their results. A two-way repeated-measures analysis of variance was applied to analyze regional differences in injury. RESULTS The mean and standard deviation of raw strain values (circumferential strain, longitudinal strain, and minimum principal strain angle) are presented over the entire LV in our normal strain database. Of the 42 patients with AI, 15 could be defined as having poor function by multiparametric systolic strain analysis. In AI patients with poor function, statistical analysis showed significant differences in injury between standard LV regions (F(3.69,44.33) = 3.47, p = 0.017) and levels (F(1.49,17.88) = 4.41, p = 0.037) of the LV, whereas no significant differences were seen in the group with normal cardiac function. CONCLUSIONS Patients with poor function, as defined by multiparametric systolic strain z scores, exhibit a consistent, heterogeneous pattern of contractile injury in which the septum and posterior regions at the base are most injured.
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Affiliation(s)
- Andrew K Knutsen
- Department of Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Young AA, Crossman DJ, Ruygrok PN, Cannell MB. Mapping system for coregistration of cardiac mri and ex vivo tissue sampling. J Magn Reson Imaging 2011; 34:1065-71. [DOI: 10.1002/jmri.22714] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 06/08/2011] [Indexed: 11/11/2022] Open
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Ibrahim ESH. Myocardial tagging by cardiovascular magnetic resonance: evolution of techniques--pulse sequences, analysis algorithms, and applications. J Cardiovasc Magn Reson 2011; 13:36. [PMID: 21798021 PMCID: PMC3166900 DOI: 10.1186/1532-429x-13-36] [Citation(s) in RCA: 203] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 07/28/2011] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular magnetic resonance (CMR) tagging has been established as an essential technique for measuring regional myocardial function. It allows quantification of local intramyocardial motion measures, e.g. strain and strain rate. The invention of CMR tagging came in the late eighties, where the technique allowed for the first time for visualizing transmural myocardial movement without having to implant physical markers. This new idea opened the door for a series of developments and improvements that continue up to the present time. Different tagging techniques are currently available that are more extensive, improved, and sophisticated than they were twenty years ago. Each of these techniques has different versions for improved resolution, signal-to-noise ratio (SNR), scan time, anatomical coverage, three-dimensional capability, and image quality. The tagging techniques covered in this article can be broadly divided into two main categories: 1) Basic techniques, which include magnetization saturation, spatial modulation of magnetization (SPAMM), delay alternating with nutations for tailored excitation (DANTE), and complementary SPAMM (CSPAMM); and 2) Advanced techniques, which include harmonic phase (HARP), displacement encoding with stimulated echoes (DENSE), and strain encoding (SENC). Although most of these techniques were developed by separate groups and evolved from different backgrounds, they are in fact closely related to each other, and they can be interpreted from more than one perspective. Some of these techniques even followed parallel paths of developments, as illustrated in the article. As each technique has its own advantages, some efforts have been made to combine different techniques together for improved image quality or composite information acquisition. In this review, different developments in pulse sequences and related image processing techniques are described along with the necessities that led to their invention, which makes this article easy to read and the covered techniques easy to follow. Major studies that applied CMR tagging for studying myocardial mechanics are also summarized. Finally, the current article includes a plethora of ideas and techniques with over 300 references that motivate the reader to think about the future of CMR tagging.
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Miura M, Hirose M, Endoh H, Wakayama Y, Sugai Y, Nakano M, Fukuda K, Shindoh C, Shirato K, Shimokawa H. Acceleration of Ca2+ waves in monocrotaline-induced right ventricular hypertrophy in the rat. Circ J 2011; 75:1343-9. [PMID: 21467666 DOI: 10.1253/circj.cj-10-1050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Triggered arrhythmias arise from delayed afterdepolarizations (DADs), with Ca(2+) waves playing an important role in their formation. In ventricular hypertrophy, however, it remains unclear how Ca(2+) waves change their propagation features and affect arrhythmogenesis. We addressed this important issue in a rat model of hypertrophy. METHODS AND RESULTS Rats were given a subcutaneous injection of 60 mg/kg monocrotaline (MCT-rats) or solvent (Ctr-rats). After 4 weeks, MCT-rats showed high right ventricular (RV) pressure and RV hypertrophy. Trabeculae were dissected from 36 right ventricles. The force was measured using a silicon strain gauge and regional intracellular Ca(2+) ([Ca(2+)](i)) was determined using microinjected fura-2. Reproducible Ca(2+) waves were induced by stimulus trains (2 Hz, 7.5s). MCT-rats showed a higher diastolic [Ca(2+)](i) and faster and larger Ca(2+) waves (P<0.01). The velocity and amplitude of Ca(2+) waves were correlated with the diastolic [Ca(2+)](i) both in the Ctr- and MCT-rats. The velocity of Ca(2+) waves in the MCT-rats was larger at the given amplitude of Ca(2+) waves than that in the Ctr-rats (P < 0.01). The amplitude of DADs was correlated with the velocity and amplitude of Ca(2+) waves in the Ctr- and MCT-rats. CONCLUSIONS The results suggest that an increase in diastolic [Ca(2+)](i) and an increase in Ca(2+) sensitivity of the sarcoplasmic reticulum Ca(2+) release channel accelerate Ca(2+) waves in ventricular hypertrophy, thereby causing arrhythmogenesis.
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Affiliation(s)
- Masahito Miura
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, Japan.
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Chuang JS, Zemljic-Harpf A, Ross RS, Frank LR, McCulloch AD, Omens JH. Determination of three-dimensional ventricular strain distributions in gene-targeted mice using tagged MRI. Magn Reson Med 2011; 64:1281-8. [PMID: 20981782 DOI: 10.1002/mrm.22547] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A model-based method for calculating three-dimensional (3D) cardiac wall strain distributions in the mouse has been developed and tested in a genetically engineered mouse model of dilated cardiomyopathy. Data from MR tagging and harmonic phase (HARP) tracking were used to measure material point displacements, and 3D Lagrangian strains were calculated throughout the entire left ventricle (LV) with a deformable parametric model. A mouse model where cardiomyocytes are specifically made deficient in vinculin (VclKO) were compared to wild-type (WT) littermates. 3D strain analysis revealed differences in LV wall mechanics between WT and VclKO mice at 8 weeks of age when systolic function had just begun to decline. Most notably, end-systolic radial strain and torsional shear were reduced in VclKO hearts which contributed to regional mechanical dysfunction. This study demonstrates the feasibility of using MRI tagging methods to detect alterations in 3D myocardial strain distributions in genetically engineered mouse models of cardiovascular disease.
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Affiliation(s)
- Joyce S Chuang
- Department of Bioengineering, University of California-San Diego, La Jolla, California, USA
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Chai JW, Chen WH, Chen HM, Chiang CM, Huang JL, Fu J, Chi-Chang Chen C, Lee SK. Correction of left ventricular wall thickening from short-axis cine MRI for basal-descent through-plane motion. J Magn Reson Imaging 2011; 33:464-73. [DOI: 10.1002/jmri.22462] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Sobajima M, Nozawa T, Suzuki T, Ohori T, Shida T, Matsuki A, Inoue H. Impact of myocardial perfusion abnormality on prognosis in patients with non-ischemic dilated cardiomyopathy. J Cardiol 2010; 56:280-6. [DOI: 10.1016/j.jjcc.2010.06.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 06/10/2010] [Accepted: 06/14/2010] [Indexed: 11/29/2022]
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Miura M, Nishio T, Hattori T, Murai N, Stuyvers BD, Shindoh C, Boyden PA. Effect of nonuniform muscle contraction on sustainability and frequency of triggered arrhythmias in rat cardiac muscle. Circulation 2010; 121:2711-7. [PMID: 20547931 DOI: 10.1161/circulationaha.109.907717] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Arrhythmias are benign or lethal, depending on their sustainability and frequency. To determine why lethal arrhythmias are prone to occur in diseased hearts, usually characterized by nonuniform muscle contraction, we investigated the effect of nonuniformity on sustainability and frequency of triggered arrhythmias. METHODS AND RESULTS Force, membrane potential, and intracellular Ca(2+) concentration ([Ca(2+)](i)) were measured in 51 rat ventricular trabeculae. Nonuniform contraction was produced by exposing a restricted region of muscle to a jet of 20 mmol/L 2,3-butanedione monoxime (BDM) or 20 mumol/L blebbistatin. Sustained arrhythmias (>10 seconds) could be induced by stimulus trains for 7.5 seconds only with the BDM or blebbistatin jet (100 nmol/L isoproterenol, 1.0 mmol/L [Ca(2+)](o), 24 degrees C). During sustained arrhythmias, Ca(2+) surges preceded synchronous increases in [Ca(2+)](i), whereas the stoppage of the BDM jet made the Ca(2+) surges unclear and arrested sustained arrhythmias (n=6). With 200 nmol/L isoproterenol, 2.5 mmol/L [Ca(2+)](o), and the BDM jet, lengthening or shortening of the muscle during sustained arrhythmias accelerated or decelerated their cycle in both the absence (n=10) and presence (n=10) of 100 mumol/L streptomycin, a stretch-activated channel blocker, respectively. The maximum rate of force relaxation correlated inversely with the change in cycle lengths (n=14; P<0.01). Sustained arrhythmias with the BDM jet were significantly accelerated by 30 mumol/L SCH00013, a Ca(2+) sensitizer of myofilaments (n=10). CONCLUSIONS These results suggest that nonuniformity of muscle contraction is an important determinant of the sustainability and frequency of triggered arrhythmias caused by the surge of Ca(2+) dissociated from myofilaments in cardiac muscle.
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Affiliation(s)
- Masahito Miura
- Department of Clinical Physiology, Health Science, Tohoku University Graduate School of Medicine, Sendai, Japan.
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Cupps BP, Taggar AK, Reynolds LM, Lawton JS, Pasque MK. Regional myocardial contractile function: multiparametric strain mapping. Interact Cardiovasc Thorac Surg 2010; 10:953-7. [PMID: 20233804 DOI: 10.1510/icvts.2009.220384] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Magnetic resonance imaging (MRI) with tissue tagging enables the quantification of multiple strain indices that can be combined through normalization into a single multiparametric index of regional myocardial contractile function. The aim of this study was to test the ability of multiparametric strain analysis to quantify regional differences in contractile function in an ovine model of myocardial injury. Regional variance in myocardial contractile function was induced in eight sheep by the ligation of the blood supply to the anterior and apical left ventricular (LV) myocardial walls. LV systolic strain was obtained from tissue tagged MRI images. A normal strain database (n=50) defines all parameters of systolic strain and allows normalization of regional function at 15,300 LV points by calculation of a z-score. Multiparametric systolic strain z-scores were therefore determined for 15,300 points in each injured sheep left ventricle. Multiparametric z-scores were found to vary significantly by region (P<0.001). z-Scores in regions remote to the infarct were found to be significantly smaller than those in the regions most likely to include infarcted myocardium. In this pre-clinical evaluation of MRI-based multiparametric strain analysis, it accurately quantified and visually defined regional differences in myocardial contractile function.
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Affiliation(s)
- Brian P Cupps
- Department of Surgery, Washington University School of Medicine, 660 South Euclid, Campus Box 8234, St. Louis, MO 63110, USA.
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ter Keurs HEDJ, Diao N, Deis NP. Nonuniform activation and the mechanics of myocardial trabeculae with fast or slow myosin. Ann N Y Acad Sci 2010; 1188:165-76. [PMID: 20201900 DOI: 10.1111/j.1749-6632.2009.05097.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Left ventricular (LV) wall motion abnormalities reflect regional nonuniform contraction which may be arrhythmogenic. We studied sarcomere mechanics and force development (F) in uniform and nonuniform trabeculae using a model in which half of the muscle can be rendered weak by exposure to low [Ca2+]o. Stretch allowed the weak muscle segment to generate a force that was four-fold higher than force when the whole muscle was exposed to low [Ca2+]o. The sarcomere force-velocity relationships (FSVR) and the force-sarcomere-length relationships (FSLR) explained the force increase in the weak segment and the decrease of force in the strong segment such that both carried the same force. Correction for muscle stiffness converted the FSVR into a [Ca2+]o-independent linear FVRXB for "the single cross-bridge (XB)." Stretch increased XB force<10% above FXB-max, but recruited more XBs by feedback of V to the rate of XB, weakening (g=g0+g1V). The g1 here was indistinguishable from g1 of XBs in slow myosin of aged animals. The mechanics of nonuniform muscle can be explained by a linear FVRXB combined with the effect of V on the XB weakening rate.
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Affiliation(s)
- Henk E D J ter Keurs
- Department of Cardiac Sciences of the Libin Institute at the Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
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Shehata ML, Cheng S, Osman NF, Bluemke DA, Lima JAC. Myocardial tissue tagging with cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2009; 11:55. [PMID: 20025732 PMCID: PMC2809051 DOI: 10.1186/1532-429x-11-55] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Accepted: 12/21/2009] [Indexed: 12/23/2022] Open
Abstract
Cardiovascular magnetic resonance (CMR) is currently the gold standard for assessing both global and regional myocardial function. New tools for quantifying regional function have been recently developed to characterize early myocardial dysfunction in order to improve the identification and management of individuals at risk for heart failure. Of particular interest is CMR myocardial tagging, a non-invasive technique for assessing regional function that provides a detailed and comprehensive examination of intra-myocardial motion and deformation. Given the current advances in gradient technology, image reconstruction techniques, and data analysis algorithms, CMR myocardial tagging has become the reference modality for evaluating multidimensional strain evolution in the human heart. This review presents an in depth discussion on the current clinical applications of CMR myocardial tagging and the increasingly important role of this technique for assessing subclinical myocardial dysfunction in the setting of a wide variety of myocardial disease processes.
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Affiliation(s)
- Monda L Shehata
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Susan Cheng
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nael F Osman
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David A Bluemke
- Department of Radiology, National Institutes of Health, Bethesda, MD, USA
| | - João AC Lima
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Sueyoshi E, Sakamoto I, Hayashida T, Uetani M. Quantification of enhancement of left ventricular myocardium in patients with dilated cardiomyopathy using delayed enhanced MR imaging. Comput Med Imaging Graph 2009; 33:547-52. [DOI: 10.1016/j.compmedimag.2009.05.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 02/24/2009] [Accepted: 05/15/2009] [Indexed: 10/20/2022]
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Plewka M, Krzemińska-Pakuła M, Drozdz J, Ciesielczyk M, Wierzbowska K, Kasprzak JD. Tissue Doppler echocardiographic identification of ischemic etiology in patients with dilated cardiomyopathy. SCAND CARDIOVASC J 2009; 39:334-41. [PMID: 16352485 DOI: 10.1080/14017430510035970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To compare the left ventricular function in patients with ischemic and nonischemic cardiomyopathy using tissue Doppler echocardiography (TDE). METHODS We studied 30 patients after myocardial infarction (MI group), 30 patients with dilated cardiomyopathy (DCM group) and 60 healthy volunteers in corresponding control groups. TDE velocities, time intervals of cardiac cycle were measured and dispersion index of TDE parameters was calculated. RESULTS Early diastolic velocities were lower in MI group than in DCM group, with similar systolic and late diastolic velocities. The dispersion index of systolic velocities was significantly higher in MI than in DCM group and in controls (respectively 33.1+/-6.0% vs 12.6+/-3.7% vs 15.9+/-5.6%; p < 0.001) and differentiated ischemic from idiopathic dilated cardiomyopathy. In MI group, preejection period was shorter and isovolumic relaxation and diastasis time were longer than in DCM group, with no differences in dispersion index of time intervals between the groups. CONCLUSIONS TDE parameters: early diastolic velocity, preejection period, isovolumic relaxation time and the dispersion index of systolic velocities differentiate ischemic and nonischemic etiology of dilated cardiomyopathy.
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Affiliation(s)
- Michał Plewka
- II Chair and Department of Cardiology, Medical University of Lodz, Bieganski Hospital, Kniaziewicza 115, 9A-347 Lodz, Poland.
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Joseph S, Moazami N, Cupps BP, Howells A, Craddock H, Ewald G, Rogers J, Pasque MK. Magnetic resonance imaging-based multiparametric systolic strain analysis and regional contractile heterogeneity in patients with dilated cardiomyopathy. J Heart Lung Transplant 2009; 28:388-94. [PMID: 19332267 DOI: 10.1016/j.healun.2008.12.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 10/17/2008] [Accepted: 12/16/2008] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Myocardial systolic strain patterns in dilated cardiomyopathy are considered non-homogeneous but have not been investigated with magnetic resonance imaging (MRI)-based multiparametric systolic strain analysis. Left ventricular (LV) 3-dimensional (3D) multiparametric systolic strain analysis is sensitive to regional contractility and is generated from sequential MRI of tissue-tagging gridline-point displacements. METHODS Sixty normal human volunteers underwent MRI-based 3D systolic strain analysis to supply normal average and standard deviation values for each of three strain parameters at each of 15,300 individual LV grid-points. Patient-specific multiparametric systolic strain data from each dilated cardiomyopathy patient (n = 10) were then subjected to a point-by-point comparison (n = 15,300 LV points) to the normal strain database for three individual strain components (45,900 database comparisons per patient). The resulting composite multiparametric Z-score values (standard deviation from normal average) were color contour mapped over patient-specific 3D LV geometry to detect the normalized regional contractile patterns associated with dilated cardiomyopathy. RESULTS Average multiparametric strain Z-score values varied significantly according to ventricular level (p = 0.001) and region (p = 0.003). Apical Z-scores were significantly less than those in both the base (p = 0.037) and mid-ventricle (p = 0.002), whereas anterolateral wall Z-scores were less than those in the anteroseptal (p = 0.023) and posteroseptal walls (p = 0.028). CONCLUSIONS MRI-based multiparametric systolic strain analysis suggests that myocardial systolic strain in patients with dilated cardiomyopathy has a heterogeneous regional distribution and, on average, falls almost 2 standard deviations from normal.
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Affiliation(s)
- Susan Joseph
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Koikkalainen JR, Antila M, Lötjönen JMP, Heliö T, Lauerma K, Kivistö SM, Sipola P, Kaartinen MA, Kärkkäinen STJ, Reissell E, Kuusisto J, Laakso M, Orešič M, Nieminen MS, Peuhkurinen KJ. Early Familial Dilated Cardiomyopathy: Identification with Determination of Disease State Parameter from Cine MR Image Data. Radiology 2008; 249:88-96. [DOI: 10.1148/radiol.2491071584] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Ter Keurs HEDJ, Shinozaki T, Zhang YM, Wakayama Y, Sugai Y, Kagaya Y, Miura M, Boyden PA, Stuyvers BDM, Landesberg A. Sarcomere mechanics in uniform and nonuniform cardiac muscle: a link between pump function and arrhythmias. Ann N Y Acad Sci 2008; 1123:79-95. [PMID: 18375580 DOI: 10.1196/annals.1420.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Starling's law and the end-systolic pressure-volume relationship (ESPVR) reflect the effect of sarcomere length (SL) on the development of stress (sigma) and shortening by myocytes in the uniform ventricle. We show here that tetanic contractions of rat cardiac trabeculae exhibit a sigma-SL relationship at saturating [Ca2+] that depends on sarcomere geometry in a manner similar to that of skeletal sarcomeres and the existence of opposing forces in cardiac muscle shortened below slack length. The sigma-SL -[Ca2+](free) relationships (sigma-SL-Ca relationships) at submaximal [Ca2+] in intact and skinned trabeculae were similar, although the sensitivity for Ca2+ of intact muscle was higher. We analyzed the mechanisms underlying the sigma-SL-Ca relationship by using a kinetic model assuming that the rates of Tn-C Ca2+ binding and/or cross-bridge (XB) cycling are determined by either the SL, [Ca2+], or sigma. We analyzed the correlation between the model results and steady-state sigma measurements at varied SL at [Ca2+] from skinned rat cardiac trabeculae to test the hypotheses that the dominant feedback mechanism is SL-, sigma-, or [Ca2+]-dependent, and that the feedback mechanism regulates Tn-C Ca2+ affinity, XB kinetics, or the unitary XB force. The analysis strongly suggests that the feedback of the number of strong XBs to cardiac Tn-C Ca2+ affinity is the dominant mechanism regulating XB recruitment. Using this concept in a model of twitch-sigma accurately reproduced the sigma-SL-Ca relationship and the time courses of twitch sigma and the intracellular [Ca2+]i. The foregoing concept has equally important repercussions for the nonuniformly contracting heart, in which arrhythmogenic Ca2+ waves arise from weakened areas in the cardiac muscle. These Ca2+ waves can reversibly be induced with nonuniform excitation-contraction coupling (ECC) by the cycle of stretch and release in the border zone between the damaged and intact regions. Stimulus trains induced propagating Ca2+ waves and reversibly induced arrhythmias. We hypothesize that rapid force loss by the sarcomeres in the border zone during relaxation causes Ca2+ release from Tn-C and initiates Ca2+ waves propagated by the sarcoplasmic reticulum (SR). Modeling of the response of the cardiac twitch to rapid force changes using the feedback concept uniquely predicts the occurrence of [Ca2+]i transients as a result of accelerated Ca2+ dissociation from Tn-C. These results are consistent with the hypothesis that a force feedback to Ca2+ binding by Tn-C is responsible for Starling's law and the ESPVR in the uniform myocardium and leads to a surge of Ca2+ released by the myofilaments during relaxation in the nonuniform myocardium, which initiates arrhythmogenic propagating Ca2+ release by the SR.
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Affiliation(s)
- Henk E D J Ter Keurs
- Department of Physiology, School of Medicine, University of Calgary, 3330 Hospital Dr., N.W., Calgary, Alberta T2N 4N1, Canada.
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Miura M, Wakayama Y, Endoh H, Nakano M, Sugai Y, Hirose M, ter Keurs HE, Shimokawa H. Spatial non-uniformity of excitation-contraction coupling can enhance arrhythmogenic-delayed afterdepolarizations in rat cardiac muscle. Cardiovasc Res 2008; 80:55-61. [DOI: 10.1093/cvr/cvn162] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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ter Keurs HE, Shinozaki T, Zhang YM, Zhang ML, Wakayama Y, Sugai Y, Kagaya Y, Miura M, Boyden PA, Stuyvers BD, Landesberg A. Sarcomere mechanics in uniform and non-uniform cardiac muscle: A link between pump function and arrhythmias. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2008; 97:312-31. [DOI: 10.1016/j.pbiomolbio.2008.02.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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