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Liu J, Li Y, Cui Y, Cao Y, Yao S, Zhou X, Wetzl J, Zeng W, Shi H. Quantification of myocardial strain in patients with isolated left ventricular non-compaction and healthy subjects using deformable registration algorithm: comparison with feature tracking. BMC Cardiovasc Disord 2020; 20:400. [PMID: 32883201 PMCID: PMC7469314 DOI: 10.1186/s12872-020-01668-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 08/13/2020] [Indexed: 11/20/2022] Open
Abstract
Background Systolic dysfunction of the left ventricle is frequently associated with isolated left ventricular non-compaction (iLVNC). Clinically, the ejection fraction (EF) is the primary index of cardiac function. However, changes of EF usually occur later in the disease course. Feature tracking (FT) and deformable registration algorithm (DRA) have become appealing techniques for myocardial strain assessment. Methods Thirty patients with iLVNC (36.7 ± 13.3 years old) and fifty healthy volunteers (42.3 ± 13.6 years old) underwent cardiovascular magnetic resonance (CMR) examination on a 1.5 T MR scanner. Strain values in the radial, circumferential, longitudinal directions were analyzed based on the short-axis and long-axis cine images using FT and DRA methods. The iLVNC patients were further divided based on the ejection fraction, into EF ≥ 50% group (n = 11) and EF < 50% group (n = 19). Receiver-operating-characteristic (ROC) analysis was performed to assess the diagnostic performance of the global strain values. Intraclass correlation coefficient (ICC) analysis was used to evaluate the intra- and inter-observer agreement. Results Global radial strain (GRS) was statistically lower in EF ≥ 50% group compared with control group [GRS (DRA)/% vs. controls: 34.6 ± 7.0 vs. 37.6 ± 7.2, P < 0.001; GRS (FT)/% vs. controls: 37.4 ± 13.2 vs. 56.9 ± 16.4, P < 0.01]. ROC analysis of global strain values derived from DRA and FT demonstrated high area under curve (range, 0.743–0.854). DRA showed excellent intra- and inter-observer agreement of global strain in both iLVNC patients (ICC: 0.995–0.999) and normal controls (ICC: 0.934–0.996). While for FT analysis, global radial strain of normal controls showed moderate intra-observer (ICC: 0.509) and poor inter-observer agreement (ICC: 0.394). Conclusions In patients with iLVNC, DRA can be used to quantitatively analyze the strain of left ventricle, with global radial strain being an earlier marker of LV systolic dysfunction. DRA has better reproducibility in evaluating both the global and segmental strain.
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Affiliation(s)
- Jia Liu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Yumin Li
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Yue Cui
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Yukun Cao
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China
| | - Sheng Yao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xiaoyue Zhou
- MR Collaboration, Siemens Healthineers Ltd., Shanghai, China
| | | | - Wenjuan Zeng
- Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
| | - Heshui Shi
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. .,Hubei Province Key Laboratory of Molecular Imaging, Wuhan, 430022, China.
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2
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Zhang X, Liu ZQ, Singh D, Powell DK, Chung CS, Campbell KS, Wenk JF. Differential Effects of Isoproterenol on Regional Myocardial Mechanics in Rat using 3D cine DENSE Cardiovascular Magnetic Resonance. J Biomech Eng 2018; 141:2696750. [PMID: 30098173 DOI: 10.1115/1.4041042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Indexed: 01/03/2023]
Abstract
The present study assessed the acute effects of isoproterenol on left ventricular (LV) mechanics in healthy rats with the hypothesis that ß-adrenergic stimulation influences the mechanics of different myocardial regions of the LV wall in different ways. To accomplish this, magnetic resonance images were obtained in the LV of healthy rats with or without isoproterenol infusion. The LV contours were divided into basal, mid-ventricular, and apical regions. Additionally, the mid-ventricular myocardium was divided into three transmural layers with each layer partitioned into four segments (i.e., septal, inferior, lateral, and anterior). Peak systolic strains and torsion were quantified for each region. Isoproterenol significantly increased peak systolic radial strain and circumferential-longitudinal shear strain, as well as ventricular torsion, throughout the basal, mid-ventricle, and apical regions. In the mid-ventricle, isoproterenol significantly increased peak systolic radial strain, and induced significant increases in peak systolic circumferential strain and longitudinal strain in the septum. Isoproterenol consistently increased peak systolic circumferential-longitudinal shear strain in all mid-ventricular segments. Ventricular torsion was significantly increased in nearly all segments except the inferior sub-endocardium. The effects of isoproterenol on LV systolic mechanics (i.e., 3D strains and torsion) in healthy rats depend on the region. This region-dependency is also strain component-specific. These results provide insight into the regional response of LV mechanics to ß-adrenergic stimulation in rats, and could act as a baseline for future studies on subclinical abnormalities associated with the inotropic response in heart disease.
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Affiliation(s)
- Xiaoyan Zhang
- Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA
| | - Zhan-Qiu Liu
- Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA
| | - Dara Singh
- Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA
| | - David K Powell
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY, USA
| | - Charles S Chung
- Department of Physiology, Wayne State University, Detroit, MI, USA; Department of Physiology, University of Kentucky, Lexington, KY, USA
| | | | - Jonathan F Wenk
- Department of Surgery, University of Kentucky, Lexington, KY, USA
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3
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Keller EJ, Fang S, Lin K, Freed BH, Smith PM, Spottiswoode BS, Davids R, Carr M, Jolly MP, Markl M, Carr JC, Collins JD. The consistency of myocardial strain derived from heart deformation analysis. Int J Cardiovasc Imaging 2017; 33:1169-1177. [DOI: 10.1007/s10554-017-1090-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 02/02/2017] [Indexed: 11/24/2022]
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Vanhoutte L, Gerber BL, Gallez B, Po C, Magat J, Balligand JL, Feron O, Moniotte S. High field magnetic resonance imaging of rodents in cardiovascular research. Basic Res Cardiol 2016; 111:46. [PMID: 27287250 DOI: 10.1007/s00395-016-0565-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 06/01/2016] [Indexed: 02/07/2023]
Abstract
Transgenic and gene knockout rodent models are primordial to study pathophysiological processes in cardiovascular research. Over time, cardiac MRI has become a gold standard for in vivo evaluation of such models. Technical advances have led to the development of magnets with increasingly high field strength, allowing specific investigation of cardiac anatomy, global and regional function, viability, perfusion or vascular parameters. The aim of this report is to provide a review of the various sequences and techniques available to image mice on 7-11.7 T magnets and relevant to the clinical setting in humans. Specific technical aspects due to the rise of the magnetic field are also discussed.
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Affiliation(s)
- Laetitia Vanhoutte
- Department of Paediatric Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium. .,Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium.
| | - Bernhard L Gerber
- Division of Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium.,Pole of Cardiovascular Research (CARD), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Bernard Gallez
- Biomedical Magnetic Resonance Unit (REMA), Louvain Drug Research Institute (LDRI), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Chrystelle Po
- CNRS, ICube, FMTS, Institut de Physique Biologique, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Julie Magat
- L'Institut de RYthmologie et de Modélisation Cardiaque (LIRYC), Inserm U1045, Bordeaux, France
| | - Jean-Luc Balligand
- Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Olivier Feron
- Pole of Pharmacology and Therapeutics (FATH), Institute of Experimental and Clinical Research (IREC), Université Catholique de Louvain (UCL), Brussels, Belgium
| | - Stéphane Moniotte
- Department of Paediatric Cardiology, Cliniques universitaires Saint Luc, Université Catholique de Louvain (UCL), Brussels, Belgium
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Jiang K, Jiao S, Vitko M, Darrah R, Flask CA, Hodges CA, Yu X. The impact of Cystic Fibrosis Transmembrane Regulator Disruption on cardiac function and stress response. J Cyst Fibros 2016; 15:34-42. [PMID: 26119592 PMCID: PMC4691219 DOI: 10.1016/j.jcf.2015.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2015] [Revised: 06/10/2015] [Accepted: 06/10/2015] [Indexed: 01/05/2023]
Abstract
BACKGROUND Altered cardiac function has been observed in cystic fibrosis transmembrane regulator (CFTR) knockout mice. However, whether this alteration is a direct effect of CFTR disruption in the heart, or is secondary due to systemic loss of CFTR, remains to be elucidated. METHODS Cardiac function of mice with muscle-specific or global knockout of CFTR was evaluated at baseline and under β-stimulation by MRI in vivo. Myocyte contractility and Ca2+ transients were measured in vitro. RESULTS Both CFTR knockout models showed increased twist and torsion at baseline. Response to β-stimulation was unaltered in muscle-specific CFTR knockout mice and was slightly decreased in global CFTR knockout mice. Aortic diameter was also decreased in both mouse models. No difference was observed in myocyte contractility and Ca2+ transients. CONCLUSIONS CFTR disruption leads to increased myocardial contractility at baseline, which may trigger untoward myocardial remodeling in CF patients that is independent of lung diseases.
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Affiliation(s)
- Kai Jiang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA
| | - Sen Jiao
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA
| | - Megan Vitko
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Rebecca Darrah
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Chris A Flask
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; Department of Radiology, Case Western Reserve University, Cleveland, OH, USA; Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA; Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA
| | - Craig A Hodges
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA; Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; Department of Radiology, Case Western Reserve University, Cleveland, OH, USA; Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA; Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, USA.
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Kowallick JT, Morton G, Lamata P, Jogiya R, Kutty S, Lotz J, Hasenfuß G, Nagel E, Chiribiri A, Schuster A. Inter-study reproducibility of left ventricular torsion and torsion rate quantification using MR myocardial feature tracking. J Magn Reson Imaging 2015; 43:128-37. [PMID: 26114731 DOI: 10.1002/jmri.24979] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 06/02/2015] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND To determine the inter-study reproducibility of MR feature tracking (MR-FT) derived left ventricular (LV) torsion and torsion rates for a combined assessment of systolic and diastolic myocardial function. METHODS Steady-state free precession (SSFP) cine LV short-axis stacks were acquired at 9:00 (Exam A), 9:30 (Exam B), and 14:00 (Exam C) in 16 healthy volunteers at 3 Tesla. SSFP images were analyzed offline using MR-FT to assess rotational displacement in apical and basal slices. Global peak torsion, peak systolic and peak diastolic torsion rates were calculated using different definitions ("twist", "normalized twist" and "circumferential-longitudinal (CL) shear angle"). Exam A and B were compared to assess the inter-study reproducibility. Morning and afternoon scans were compared to address possible diurnal variation. RESULTS The different methods showed good inter-study reproducibility for global peak torsion (intraclass correlation coefficient [ICC]: 0.90-0.92; coefficient of variation [CoV]: 19.0-20.3%) and global peak systolic torsion rate (ICC: 0.82-0.84; CoV: 25.9-29.0%). Conversely, global peak diastolic torsion rate showed little inter-study reproducibility (ICC: 0.34-0.47; CoV: 40.8-45.5%). Global peak torsion as determined by the CL shear angle showed the best inter-study reproducibility (ICC: 0.90;CoV: 19.0%). MR-FT results were not measurably affected by diurnal variation between morning and afternoon scans (CL shear angle: 4.8 ± 1.4°, 4.8 ± 1.5°, and 4.1 ± 1.6° for Exam A, B, and C, respectively; P = 0.21). CONCLUSION MR-FT based derivation of myocardial peak torsion and peak systolic torsion rate has high inter-study reproducibility as opposed to peak diastolic torsion rate. The CL shear angle was the most reproducible parameter independently of cardiac anatomy and may develop into a robust tool to quantify cardiac rotational mechanics in longitudinal MR-FT patient studies.
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Affiliation(s)
- Johannes T Kowallick
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom.,Institute for Diagnostic and Interventional Radiology, Georg-August-University Göttingen, Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Germany
| | - Geraint Morton
- Portsmouth Hospitals NHS Trust, Portsmouth, United Kingdom
| | - Pablo Lamata
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom.,Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Roy Jogiya
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom
| | - Shelby Kutty
- Children's Hospital and Medical Center, University of Nebraska College of Medicine, Omaha, Nebraska, USA
| | - Joachim Lotz
- Institute for Diagnostic and Interventional Radiology, Georg-August-University Göttingen, Göttingen, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Germany
| | - Gerd Hasenfuß
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Germany.,Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
| | - Eike Nagel
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom
| | - Amedeo Chiribiri
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom
| | - Andreas Schuster
- Division of Imaging Sciences and Biomedical Engineering, The Rayne Institute, St Thomas' Hospital, King's College London, London, United Kingdom.,DZHK (German Centre for Cardiovascular Research), partner site Göttingen, Germany.,Department of Cardiology and Pneumology, Georg-August-University Göttingen, Göttingen, Germany
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7
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Sampath S, Klimas M, Feng D, Baumgartner R, Manigbas E, Liang AL, Evelhoch JL, Chin CL. Characterization of regional left ventricular function in nonhuman primates using magnetic resonance imaging biomarkers: a test-retest repeatability and inter-subject variability study. PLoS One 2015; 10:e0127947. [PMID: 26010607 PMCID: PMC4444127 DOI: 10.1371/journal.pone.0127947] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/20/2015] [Indexed: 12/22/2022] Open
Abstract
Pre-clinical animal models are important to study the fundamental biological and functional mechanisms involved in the longitudinal evolution of heart failure (HF). Particularly, large animal models, like nonhuman primates (NHPs), that possess greater physiological, biochemical, and phylogenetic similarity to humans are gaining interest. To assess the translatability of these models into human diseases, imaging biomarkers play a significant role in non-invasive phenotyping, prediction of downstream remodeling, and evaluation of novel experimental therapeutics. This paper sheds insight into NHP cardiac function through the quantification of magnetic resonance (MR) imaging biomarkers that comprehensively characterize the spatiotemporal dynamics of left ventricular (LV) systolic pumping and LV diastolic relaxation. MR tagging and phase contrast (PC) imaging were used to quantify NHP cardiac strain and flow. Temporal inter-relationships between rotational mechanics, myocardial strain and LV chamber flow are presented, and functional biomarkers are evaluated through test-retest repeatability and inter subject variability analyses. The temporal trends observed in strain and flow was similar to published data in humans. Our results indicate a dominant dimension based pumping during early systole, followed by a torsion dominant pumping action during late systole. Early diastole is characterized by close to 65% of untwist, the remainder of which likely contributes to efficient filling during atrial kick. Our data reveal that moderate to good intra-subject repeatability was observed for peak strain, strain-rates, E/circumferential strain-rate (CSR) ratio, E/longitudinal strain-rate (LSR) ratio, and deceleration time. The inter-subject variability was high for strain dyssynchrony, diastolic strain-rates, peak torsion and peak untwist rate. We have successfully characterized cardiac function in NHPs using MR imaging. Peak strain, average systolic strain-rate, diastolic E/CSR and E/LSR ratios, and deceleration time were identified as robust biomarkers that could potentially be applied to future pre-clinical drug studies.
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Affiliation(s)
- Smita Sampath
- Imaging, Merck Research Laboratories, Merck Sharp & Dohme, Singapore, Singapore
- * E-mail:
| | - Michael Klimas
- Imaging, Merck Research Laboratories, Merck & Co. Inc., West Point, Pennsylvania, United States of America
| | - Dai Feng
- Biometric Research, Merck Research Laboratories, Biostatistics and Research Decision Sciences, Merck & Co. Inc., Rahway, New Jersey, United States of America
| | - Richard Baumgartner
- Biometric Research, Merck Research Laboratories, Biostatistics and Research Decision Sciences, Merck & Co. Inc., Rahway, New Jersey, United States of America
| | | | - Ai-Leng Liang
- Imaging, Merck Research Laboratories, Merck Sharp & Dohme, Singapore, Singapore
| | - Jeffrey L. Evelhoch
- Imaging, Merck Research Laboratories, Merck & Co. Inc., West Point, Pennsylvania, United States of America
| | - Chih-Liang Chin
- Imaging, Merck Research Laboratories, Merck Sharp & Dohme, Singapore, Singapore
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8
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Collins JD. Global and regional functional assessment of ischemic heart disease with cardiac MR imaging. Radiol Clin North Am 2015; 53:369-95. [PMID: 25727001 DOI: 10.1016/j.rcl.2014.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cardiac MR imaging (CMR) combines assessment of myocardial function and tissue characterization, and is therefore ideally suited to evaluating patients with ischemic heart disease (IHD). This article discusses evaluation of left ventricular global function at CMR, reviewing the literature supporting global parameters in risk stratification and assessment of treatment response in IHD. Techniques for assessment of regional myocardial function are reviewed, and normal myocardial motion and fiber arrangement discussed. Despite barriers to clinical adoption, integration of this assessment into clinical routine should improve the ability to detect functional consequences of early myocardial structural alterations in patients with IHD.
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Affiliation(s)
- Jeremy D Collins
- Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 North Michigan Avenue, Suite 1600, Chicago, IL 60611, USA.
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9
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Jiang K, Yu X. Quantification of regional myocardial wall motion by cardiovascular magnetic resonance. Quant Imaging Med Surg 2014; 4:345-57. [PMID: 25392821 DOI: 10.3978/j.issn.2223-4292.2014.09.01] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 09/12/2014] [Indexed: 12/12/2022]
Abstract
Cardiovascular magnetic resonance (CMR) is a versatile tool that also allows comprehensive and accurate measurement of both global and regional myocardial contraction. Quantification of regional wall motion parameters, such as strain, strain rate, twist and torsion, has been shown to be more sensitive to early-stage functional alterations. Since the invention of CMR tagging by magnetization saturation in 1988, several CMR techniques have been developed to enable the measurement of regional myocardial wall motion, including myocardial tissue tagging, phase contrast mapping, displacement encoding with stimulated echoes (DENSE), and strain encoded (SENC) imaging. These techniques have been developed with their own advantages and limitations. In this review, two widely used and closely related CMR techniques, i.e., tissue tagging and DENSE, will be discussed from the perspective of pulse sequence development and image-processing techniques. The clinical and preclinical applications of tissue tagging and DENSE in assessing wall motion mechanics in both normal and diseased hearts, including coronary artery diseases, hypertrophic cardiomyopathy, aortic stenosis, and Duchenne muscular dystrophies, will be discussed.
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Affiliation(s)
- Kai Jiang
- 1 Departments of Biomedical Engineering, 2 Case Center for Imaging Research, 3 Radiology, and 4 Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio, USA
| | - Xin Yu
- 1 Departments of Biomedical Engineering, 2 Case Center for Imaging Research, 3 Radiology, and 4 Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio, USA
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10
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Chen Y, Ye L, Zhong J, Li X, Yan C, Chandler MP, Calvin S, Xiao F, Negia M, Low WC, Zhang J, Yu X. The Structural Basis of Functional Improvement in Response to Human Umbilical Cord Blood Stem Cell Transplantation in Hearts With Postinfarct LV Remodeling. Cell Transplant 2013; 24:971-83. [PMID: 24332083 DOI: 10.3727/096368913x675746] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cellular therapy for myocardial repair has been one of the most intensely investigated interventional strategies for acute myocardial infarction. Although the therapeutic potential of stem cells has been demonstrated in various studies, the underlying mechanisms for such improvements are poorly understood. In the present study, we investigated the long-term effects of stem cell therapy on both myocardial fiber organization and regional contractile function using a rat model of postinfarct remodeling. Human nonhematopoietic umbilical cord blood stem cells (nh-UCBSCs) were administered via tail vein to rats 2 days after infarct surgery. Animals were maintained without immunosuppressive therapy. In vivo and ex vivo MR imaging was performed on infarct hearts 10 months after cell transplantation. Compared to the age-matched rats exposed to the identical surgery, both global and regional cardiac functions of the nh-UCBSC-treated hearts, such as ejection fraction, ventricular strain, and torsion, were significantly improved. More importantly, the treated hearts exhibited preserved fiber orientation and water diffusivities that were similar to those in sham-operated control hearts. These data provide the first evidence that nh-UCBSC treatment may prevent/delay untoward structural remodeling in postinfarct hearts, which supports the improved LV function observed in vivo in the absence of immunosuppression, suggesting a beneficial paracrine effect occurred with the cellular therapy.
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Affiliation(s)
- Yong Chen
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
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11
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Montano MM, Desjardins CL, Doughman YQ, Hsieh YH, Hu Y, Bensinger HM, Wang C, Stelzer JE, Dick TE, Hoit BD, Chandler MP, Yu X, Watanabe M. Inducible re-expression of HEXIM1 causes physiological cardiac hypertrophy in the adult mouse. Cardiovasc Res 2013; 99:74-82. [PMID: 23585471 PMCID: PMC3687752 DOI: 10.1093/cvr/cvt086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 03/28/2013] [Accepted: 04/01/2013] [Indexed: 01/06/2023] Open
Abstract
AIMS The transcription factor hexamethylene-bis-acetamide-inducible protein 1 (HEXIM1) regulates myocardial vascularization and growth during cardiogenesis. Our aim was to determine whether HEXIM1 also has a beneficial role in modulating vascularization, myocardial growth, and function within the adult heart. METHODS AND RESULTS To achieve our objective, we created and investigated a mouse line wherein HEXIM1 was re-expressed in adult cardiomyocytes to levels found in the foetal heart. Our findings support a beneficial role for HEXIM1 through increased vascularization, myocardial growth, and increased ejection fraction within the adult heart. HEXIM1 re-expression induces angiogenesis, that is, essential for physiological hypertrophy and maintenance of cardiac function. The ability of HEXIM1 to co-ordinate processes associated with physiological hypertrophy may be attributed to HEXIM1 regulation of other transcription factors (HIF-1-α, c-Myc, GATA4, and PPAR-α) that, in turn, control many genes involved in myocardial vascularization, growth, and metabolism. Moreover, the mechanism for HEXIM1-induced physiological hypertrophy appears to be distinct from that involving the PI3K/AKT pathway. CONCLUSION HEXIM1 re-expression results in the induction of angiogenesis that allows for the co-ordination of tissue growth and angiogenesis during physiological hypertrophy.
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Affiliation(s)
- Monica M. Montano
- Department of Pharmacology, Case Western Reserve University School of Medicine, H.G. Wood Bldg. W307, 2109 Adelbert Road, Cleveland, OH 44106, USA
| | - Candida L. Desjardins
- Department of Biomedical Engineering, Case Western Reserve University School of Engineering, Cleveland, OH 44106, USA
| | - Yong Qui Doughman
- Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Genetics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Anatomy, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
| | - Yee-Hsee Hsieh
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Yanduan Hu
- Department of Pharmacology, Case Western Reserve University School of Medicine, H.G. Wood Bldg. W307, 2109 Adelbert Road, Cleveland, OH 44106, USA
| | - Heather M. Bensinger
- Department of Pharmacology, Case Western Reserve University School of Medicine, H.G. Wood Bldg. W307, 2109 Adelbert Road, Cleveland, OH 44106, USA
| | - Connie Wang
- Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Genetics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Anatomy, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
| | - Julian E. Stelzer
- Department of Physiology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Thomas E. Dick
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Brian D. Hoit
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Margaret P. Chandler
- Department of Physiology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Xin Yu
- Department of Biomedical Engineering, Case Western Reserve University School of Engineering, Cleveland, OH 44106, USA
| | - Michiko Watanabe
- Department of Pediatrics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Genetics, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
- Department of Anatomy, Case Western Reserve University School of Medicine, Rainbow Babies and Children's Hospital, 11100 Euclid Avenue, Cleveland, OH 44106, USA
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12
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Azam S, Desjardins CL, Schluchter M, Liner A, Stelzer JE, Yu X, Hoit BD. Comparison of velocity vector imaging echocardiography with magnetic resonance imaging in mouse models of cardiomyopathy. Circ Cardiovasc Imaging 2012; 5:776-81. [PMID: 22977126 DOI: 10.1161/circimaging.111.972406] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Myocardial strain imaging using echocardiography can be a cost-effective method to quantify ventricular wall motion objectively, but few studies have compared strain measured with echocardiography against magnetic resonance imaging (MRI) in small animals. METHODS AND RESULTS We compared circumferential strain (CS) and radial strain (RS) measured with echocardiography (velocity vector imaging [VVI]) to displacement encoding with stimulated-echo MRI in 2 mouse models of cardiomyopathy. In 3-month-old mice with gene targeted deficiency of cardiac myosin-binding protein-C (cMyBP-C(-/-), n=6) or muscle LIM protein (MLP(-/-), n=6), and wild-type mice (n=8), myocardial strains were measured at 3 cross-sectional levels and averaged to obtain global strains. There was modest correlation between VVI and MRI measured strains, with global CS yielding stronger correlation compared with global RS (CS R(2)=0.4452 versus RS R(2)=0.2794, both P<0.05). Overall, strain measured by VVI was more variable than MRI (P<0.05) and the limits of agreement were slightly, but not significantly (P=0.14), closer for global CS than RS. Both VVI and MRI strain measurements showed significantly lower global CS strain in the knockout groups compared with the wild type. The VVI (but not MRI) CS strain measurements were different between the 2 knockout groups (-14.5±3.8% versus -6.6±4.0%, cMyBP-C(-/-) versus MLP(-/-) respectively, P<0.05). CONCLUSIONS Measurements of left ventricular CS and RS are feasible in small animals using 2-dimensional echocardiography. VVI and MRI strain measurements correlated modestly and the agreement between the modalities tended to be greater for CS than RS. Although VVI and MRI strains were able to differentiate between wild-type and knockout mice, only global CS VVI differentiated between the 2 models of cardiomyopathy.
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Affiliation(s)
- Salman Azam
- Harrington Heart and Vascular Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH 44106-5038, USA
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13
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Ernande L, Thibault H, Bergerot C, Moulin P, Wen H, Derumeaux G, Croisille P. Systolic myocardial dysfunction in patients with type 2 diabetes mellitus: identification at MR imaging with cine displacement encoding with stimulated echoes. Radiology 2012; 265:402-9. [PMID: 22929334 DOI: 10.1148/radiol.12112571] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
PURPOSE To determine if cine displacement encoding with stimulated echoes (DENSE) can help to identify and determine the patterns of subclinical myocardial systolic dysfunction in patients with type 2 diabetes mellitus (DM) when compared with cine DENSE in control patients. MATERIALS AND METHODS After obtaining approval from the institutional ethics committee and written informed consent from the patients, 37 patients with type 2 DM without overt heart disease and 23 age-matched control patients were prospectively included in the study. The patients underwent standard cine magnetic resonance (MR) imaging with two-dimensional cine DENSE acquisitions. Circumferential (Ecc) and radial (Err) systolic strains were measured on short-axis views at basal, mid, and apical left ventricular levels. Longitudinal strain (Ell) was measured on four- and two-chamber views. Statistical testing included the intraclass correlation coefficient and multiple linear regression analysis. RESULTS The intraobserver intraclass correlation coefficient values were 0.85, 0.95, and 0.90, and the interobserver intraclass correlation coefficient values were 0.79, 0.91 and 0.80 for Ecc, Err, and Ell, respectively. The left ventricular ejection fraction was in the reference range and similar between the groups, and the patients with DM showed a decrease in Ecc (-14.4%±1.6 vs -17.0%±1.6, P<.001), Err (36.2%±10.9 vs 44.4%±9.9, P=.006) and Ell (-12.9%±2.1 vs -15.5%±1.6, P<.001) compared with the control patients. Finally, DM was independently associated with Ecc (P<.001), Err (P=.05) and Ell (P=.01) after adjustment for age, sex, hypertension, body mass index, and left ventricular mass. CONCLUSION Cine DENSE, a motion-encoding MR imaging technique for myocardial strain assessment with high spatial resolution, appears to be useful in the identification of subclinical myocardial dysfunction in patients with DM.
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Affiliation(s)
- Laura Ernande
- Service des Explorations Fonctionnelles Cardiovasculaires, Department of Endocrinology, Louis Pradel Hospital, CarMeN INSERM Unit 1060, Université de Lyon, Lyon, France
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14
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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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15
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Constantinesco A, Choquet P, Goetz C, Monassier L. PET, SPECT, CT, and MRI in Mouse Cardiac Phenotyping: An Overview. ACTA ACUST UNITED AC 2012; 2:129-44. [DOI: 10.1002/9780470942390.mo110225] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- André Constantinesco
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Philippe Choquet
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Christian Goetz
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Laurent Monassier
- Laboratoire de Neurobiologie et Pharmacologie Cardiovasculaire, Université de Strasbourg; Strasbourg France
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16
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Velocity Vector Imaging Fails to Quantify Regional Myocardial Dysfunction in a Mouse Model of Isoprenaline-Induced Cardiotoxicity. Echocardiography 2012; 29:818-26. [DOI: 10.1111/j.1540-8175.2012.01705.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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17
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Dall'Armellina E, Jung BA, Lygate CA, Neubauer S, Markl M, Schneider JE. Improved method for quantification of regional cardiac function in mice using phase-contrast MRI. Magn Reson Med 2012; 67:541-51. [PMID: 21674616 PMCID: PMC3378699 DOI: 10.1002/mrm.23022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 04/04/2011] [Accepted: 05/05/2011] [Indexed: 11/08/2022]
Abstract
Phase-contrast magnetic resonance imaging is a technique that allows for characterization of regional cardiac function and for measuring transmural myocardial velocities in human hearts with high temporal and spatial resolution. The application of this technique (also known as tissue phase mapping) to murine hearts has been very limited so far. The aim of our study was to implement and to optimize tissue phase mapping for a comprehensive assessment of murine transmural wall motion. Baseline values for regional motion patterns in mouse hearts, based on the clinically used American Heart Association's 17-segment model, were established, and a detailed motion analysis of mouse heart for the entire cardiac cycle (including epicardial and endocardial motion patterns) is provided. Black-blood contrast was found to be essential to obtain reproducible velocity encoding. Tissue phase mapping of the mouse heart permits the detailed assessment of regional myocardial velocities. While a proof-of-principle application in a murine ischemia-reperfusion model was performed, future studies are warranted to assess its potential for the investigation of systolic and diastolic functions in genetically and surgically manipulated mouse models of human heart disease.
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Affiliation(s)
- Erica Dall'Armellina
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Bernd A Jung
- Department of Radiology, Medical Physics, University Hospital FreiburgGermany
| | - Craig A Lygate
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Stefan Neubauer
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
| | - Michael Markl
- Department of Radiology, Medical Physics, University Hospital FreiburgGermany
| | - Jürgen E Schneider
- Department of Cardiovascular Medicine, University of OxfordOxford, United Kingdom
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18
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Cardiovascular Magnetic Resonance of Myocardial Structure, Function, and Perfusion in Mouse and Rat Models. CURRENT CARDIOVASCULAR IMAGING REPORTS 2012. [DOI: 10.1007/s12410-012-9122-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Zhong X, Gibberman LB, Spottiswoode BS, Gilliam AD, Meyer CH, French BA, Epstein FH. Comprehensive cardiovascular magnetic resonance of myocardial mechanics in mice using three-dimensional cine DENSE. J Cardiovasc Magn Reson 2011; 13:83. [PMID: 22208954 PMCID: PMC3278394 DOI: 10.1186/1532-429x-13-83] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 12/30/2011] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Quantitative noninvasive imaging of myocardial mechanics in mice enables studies of the roles of individual genes in cardiac function. We sought to develop comprehensive three-dimensional methods for imaging myocardial mechanics in mice. METHODS A 3D cine DENSE pulse sequence was implemented on a 7T small-bore scanner. The sequence used three-point phase cycling for artifact suppression and a stack-of-spirals k-space trajectory for efficient data acquisition. A semi-automatic 2D method was adapted for 3D image segmentation, and automated 3D methods to calculate strain, twist, and torsion were employed. A scan protocol that covered the majority of the left ventricle in a scan time of less than 25 minutes was developed, and seven healthy C57Bl/6 mice were studied. RESULTS Using these methods, multiphase normal and shear strains were measured, as were myocardial twist and torsion. Peak end-systolic values for the normal strains at the mid-ventricular level were 0.29 ± 0.17, -0.13 ± 0.03, and -0.18 ± 0.14 for E(rr), E(cc), and E(ll), respectively. Peak end-systolic values for the shear strains were 0.00 ± 0.08, 0.04 ± 0.12, and 0.03 ± 0.07 for E(rc), E(rl), and E(cl), respectively. The peak end-systolic normalized torsion was 5.6 ± 0.9°. CONCLUSIONS Using a 3D cine DENSE sequence tailored for cardiac imaging in mice at 7 T, a comprehensive assessment of 3D myocardial mechanics can be achieved with a scan time of less than 25 minutes and an image analysis time of approximately 1 hour.
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Affiliation(s)
| | | | - Bruce S Spottiswoode
- MRC/UCT Medical Imaging Research Unit, University of Cape Town, Cape Town, South Africa
| | | | - Craig H Meyer
- Radiology Department, University of Virginia, Charlottesville, USA
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
| | - Brent A French
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
| | - Frederick H Epstein
- Radiology Department, University of Virginia, Charlottesville, USA
- Biomedical Engineering Department, University of Virginia, Charlottesville, USA
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20
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Vandsburger MH, French BA, Kramer CM, Zhong X, Epstein FH. Displacement-encoded and manganese-enhanced cardiac MRI reveal that nNOS, not eNOS, plays a dominant role in modulating contraction and calcium influx in the mammalian heart. Am J Physiol Heart Circ Physiol 2011; 302:H412-9. [PMID: 22058155 DOI: 10.1152/ajpheart.00705.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Within cardiomyocytes, endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) are thought to modulate L-type calcium channel (LTCC) function and sarcoplasmic reticulum calcium cycling, respectively. However, divergent results from mostly invasive prior studies suggest more complex roles. To elucidate the roles of nNOS and eNOS in vivo, we applied noninvasive cardiac MRI to study wild-type (WT), eNOS(-/-), and nNOS(-/-) mice. An in vivo index of LTCC flux (LTCCI) was measured at baseline (Bsl), dobutamine (Dob), and dobutamine + carbacholamine (Dob + CCh) using manganese-enhanced MRI. Displacement-encoded MRI assessed contractile function by measuring circumferential strain (E(cc)) and systolic (dE(cc)/dt) and diastolic (dE(cc)/dt(diastolic)) strain rates at Bsl, Dob, and Dob + CCh. Bsl LTCCI was highest in nNOS(-/-) mice (P < 0.05 vs. WT and eNOS(-/-)) and increased only in WT and eNOS(-/-) mice with Dob (P < 0.05 vs. Bsl). LTCCI decreased significantly from Dob levels with Dob + CCh in all mice. Contractile function, as assessed by E(cc), was similar in all mice at Bsl. With Dob, E(cc) increased significantly in WT and eNOS(-/-) but not nNOS(-/-) mice (P < 0.05 vs. WT and eNOS(-/-)). With Dob + CCh, E(cc) returned to baseline levels in all mice. Systolic blood pressure, measured via tail plethysmography, was highest in eNOS(-/-) mice (P < 0.05 vs. WT and nNOS(-/-)). Mice deficient in nNOS demonstrate increased Bsl LTCC function and an attenuated contractile reserve to Dob, whereas eNOS(-/-) mice demonstrate normal LTCC and contractile function under all conditions. These results suggest that nNOS, not eNOS, plays the dominant role in modulating Ca(2+) cycling in the heart.
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Affiliation(s)
- Moriel H Vandsburger
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
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21
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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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