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Ho JE, Rahban Y, Sandhu H, Hiremath PG, Ayalon N, Qin F, Perez AJ, Downing J, Gopal DM, Cheng S, Colucci WS. Preclinical Alterations in Myocardial Microstructure in People with Metabolic Syndrome. Obesity (Silver Spring) 2017; 25:1516-1522. [PMID: 28737258 PMCID: PMC5578717 DOI: 10.1002/oby.21936] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/05/2017] [Accepted: 06/13/2017] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Metabolic syndrome (MetS) can lead to myocardial fibrosis, diastolic dysfunction, and eventual heart failure. This study evaluated alterations in myocardial microstructure in people with MetS by using a novel algorithm to characterize ultrasonic signal intensity variation. METHODS Among 254 participants without existing cardiovascular disease (mean age 42 ± 11 years, 75% women), there were 162 with MetS, 47 with obesity without MetS, and 45 nonobese controls. Standard echocardiography was performed, and a novel validated computational algorithm was used to investigate myocardial microstructure based on sonographic signal intensity and distribution. The signal intensity coefficient (SIC [left ventricular microstructure]) was examined. RESULTS The SIC was significantly higher in people with MetS compared with people with (P < 0.001) and without obesity (P = 0.04), even after adjustment for age, sex, body mass index, hypertension, diabetes mellitus, and the ratio of triglyceride (TG) to high-density lipoprotein (HDL) cholesterol (P < 0.05 for all). Clinical correlates of SIC included TG concentrations (r = 0.21, P = 0.0007) and the TG/HDL ratio (r = 0.2, P = 0.001). CONCLUSIONS This study's findings suggest that preclinical MetS and dyslipidemia in particular are associated with altered myocardial signal intensity variation. Future studies are needed to determine whether the SIC may help detect subclinical diseases in people with metabolic disease, with the ultimate goal of targeting preventive efforts.
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Affiliation(s)
- Jennifer E. Ho
- Cardiovascular Research Center and Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston, MA
| | | | - Harpaul Sandhu
- Temple Heart and Vascular Institute, Temple University, Philadelphia, PA
| | | | - Nir Ayalon
- Cardiovascular Medicine Section, Department of Medicine, Boston University, Boston, MA
| | | | - Alejandro J. Perez
- Cardiovascular Medicine Section, Department of Medicine, Boston University, Boston, MA
| | - Jill Downing
- Cardiovascular Medicine Section, Department of Medicine, Boston University, Boston, MA
| | - Deepa M. Gopal
- Cardiovascular Medicine Section, Department of Medicine, Boston University, Boston, MA
| | - Susan Cheng
- Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Wilson S. Colucci
- Cardiovascular Medicine Section, Department of Medicine, Boston University, Boston, MA
- Whitaker Cardiovascular Institute, Boston University, Boston, MA
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Hiremath P, Lawler PR, Ho JE, Correia AW, Abbasi SA, Kwong RY, Jerosch-Herold M, Ho CY, Cheng S. Ultrasonic Assessment of Myocardial Microstructure in Hypertrophic Cardiomyopathy Sarcomere Mutation Carriers With and Without Left Ventricular Hypertrophy. Circ Heart Fail 2017; 9:CIRCHEARTFAILURE.116.003026. [PMID: 27623770 DOI: 10.1161/circheartfailure.116.003026] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 08/10/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND The noninvasive assessment of altered myocardium in patients with genetic mutations that are associated with hypertrophic cardiomyopathy (HCM) remains challenging. In this pilot study, we evaluated whether a novel echocardiography-based assessment of myocardial microstructure, the signal intensity coefficient (SIC), could detect tissue-level alterations in HCM sarcomere mutation carriers with and without left ventricular hypertrophy. METHODS AND RESULTS We studied 3 groups of genotyped individuals: sarcomere mutation carriers with left ventricular hypertrophy (clinical HCM; n=36), mutation carriers with normal left ventricular wall thickness (subclinical HCM; n=28), and healthy controls (n=10). We compared measurements of echocardiographic SIC with validated assessments of cardiac microstructural alteration, including cardiac magnetic resonance measures of interstitial fibrosis (extracellular volume fraction), as well as serum biomarkers (NTproBNP, hs-cTnI, and PICP). In age-, sex-, and familial relation-adjusted analyses, the SIC was quantitatively different across subjects with overt HCM, subclinical HCM, and healthy controls (P<0.001). Compared with controls, the SIC was 61% higher in overt HCM and 47% higher in subclinical HCM (P<0.001 for both). The SIC was significantly correlated with extracellular volume (r=0.72; P<0.01), with left ventricular mass and E' velocity (r=0.45, -0.60, respectively; P<0.01 for both), and with serum NTproBNP levels (r=0.36; P<0.001). CONCLUSIONS Our findings suggest that the SIC could serve as a noninvasive quantitative tool for assessing altered myocardial tissue characteristics in patients with genetic mutations associated with HCM. Further studies are needed to determine whether the SIC could be used to identify subclinical changes in patients at risk for HCM and to evaluate the effects of interventions.
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Affiliation(s)
- Pranoti Hiremath
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Patrick R Lawler
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Jennifer E Ho
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Andrew W Correia
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Siddique A Abbasi
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Raymond Y Kwong
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Michael Jerosch-Herold
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.)
| | - Carolyn Y Ho
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.).
| | - Susan Cheng
- From the Cardiovascular Division, Department of Medicine (P.H., P.R.L., R.Y.K., C.Y.H., S.C.) and Department of Radiology (M.J.-H.), Brigham and Women's Hospital, Harvard Medical School, Boston, MA; Cardiology Division, Department of Medicine, Massachusetts General Hospital, Boston (J.E.H.); SessionM, Boston, MA (A.W.C.); and Division of Cardiology, Department of Medicine, Warren Alpert Medical School of Brown University, Providence, RI (S.A.A.).
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Oelze ML, Mamou J. Review of Quantitative Ultrasound: Envelope Statistics and Backscatter Coefficient Imaging and Contributions to Diagnostic Ultrasound. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2016; 63:336-51. [PMID: 26761606 PMCID: PMC5551399 DOI: 10.1109/tuffc.2015.2513958] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Conventional medical imaging technologies, including ultrasound, have continued to improve over the years. For example, in oncology, medical imaging is characterized by high sensitivity, i.e., the ability to detect anomalous tissue features, but the ability to classify these tissue features from images often lacks specificity. As a result, a large number of biopsies of tissues with suspicious image findings are performed each year with a vast majority of these biopsies resulting in a negative finding. To improve specificity of cancer imaging, quantitative imaging techniques can play an important role. Conventional ultrasound B-mode imaging is mainly qualitative in nature. However, quantitative ultrasound (QUS) imaging can provide specific numbers related to tissue features that can increase the specificity of image findings leading to improvements in diagnostic ultrasound. QUS imaging can encompass a wide variety of techniques including spectral-based parameterization, elastography, shear wave imaging, flow estimation, and envelope statistics. Currently, spectral-based parameterization and envelope statistics are not available on most conventional clinical ultrasound machines. However, in recent years, QUS techniques involving spectral-based parameterization and envelope statistics have demonstrated success in many applications, providing additional diagnostic capabilities. Spectral-based techniques include the estimation of the backscatter coefficient (BSC), estimation of attenuation, and estimation of scatterer properties such as the correlation length associated with an effective scatterer diameter (ESD) and the effective acoustic concentration (EAC) of scatterers. Envelope statistics include the estimation of the number density of scatterers and quantification of coherent to incoherent signals produced from the tissue. Challenges for clinical application include correctly accounting for attenuation effects and transmission losses and implementation of QUS on clinical devices. Successful clinical and preclinical applications demonstrating the ability of QUS to improve medical diagnostics include characterization of the myocardium during the cardiac cycle, cancer detection, classification of solid tumors and lymph nodes, detection and quantification of fatty liver disease, and monitoring and assessment of therapy.
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Milne ML, Singh GK, Miller JG, Wallace KD, Holland MR. Toward 3-D Echocardiographic Determination of Regional Myofiber Structure. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:607-18. [PMID: 26589530 PMCID: PMC4711925 DOI: 10.1016/j.ultrasmedbio.2015.09.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 09/15/2015] [Accepted: 09/27/2015] [Indexed: 05/10/2023]
Abstract
As a step toward the goal of relating changes in underlying myocardial structure to observed altered cardiac function in the hearts of individual patients, this study addresses the feasibility of creating echocardiography-derived maps of regional myocardial fiber structure for entire, intact, excised sheep hearts. Backscatter data were obtained from apical echocardiographic images acquired with a clinical ultrasonic imaging system and used to determine local fiber orientations in each of seven hearts. Systematic acquisition across the entire heart volume provided information sufficient to give a complete map for each heart. Results from the echocardiography-derived fiber maps compare favorably with corresponding results derived from diffusion tensor magnetic resonance imaging. The results of this study provide evidence of the feasibility of using echocardiographic methods to generate individualized whole heart fiber maps for patients.
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Affiliation(s)
- Michelle L Milne
- Department of Physics, St. Mary's College of Maryland, St. Mary's City, Maryland, USA.
| | - Gautam K Singh
- Department of Pediatrics, Washington University in St. Louis, Saint Louis, Missouri, USA
| | - James G Miller
- Department of Physics, Washington University in St. Louis, Saint Louis, Missouri, USA
| | | | - Mark R Holland
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, IUPUI, Indianapolis, Indiana, USA
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Zaidman CM, Holland MR, Hughes MS. Quantitative ultrasound of skeletal muscle: reliable measurements of calibrated muscle backscatter from different ultrasound systems. ULTRASOUND IN MEDICINE & BIOLOGY 2012; 38:1618-1625. [PMID: 22763008 PMCID: PMC3632310 DOI: 10.1016/j.ultrasmedbio.2012.04.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 02/27/2012] [Accepted: 04/25/2012] [Indexed: 06/01/2023]
Abstract
Widespread implementation of quantitative muscle ultrasonography in assessing skeletal muscle pathology is limited by an inability to replicate results between different ultrasound systems. We have developed a measurement of skeletal muscle pathology, calibrated muscle backscatter (cMB), which should be reproducible between different ultrasound systems. We compared the reliability of grayscale and cMB measurements between different ultrasound systems, configurations and region-of-interest (ROI) sizes. cMB of skeletal muscle was reliably measured (intraclass correlation coefficient [ICC] ≤0.98) despite very dissimilar grayscale levels (ICC ≤0.54). cMB reliability was highest between systems using similar settings (ICC: 0.82-0.98) and was lowest when transducer type varied (ICC: 0.47-0.71). Reliability was better from ROIs spanning a narrow range of depths compared with larger ranges. cMB measurements are more reliable than grayscale between different ultrasound systems and configurations. Measuring cMB could improve widespread implementation of quantitative ultrasound in assessments of skeletal muscle pathology.
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Affiliation(s)
- Craig M Zaidman
- Department of Neurology, Neuromuscular Division, Washington University School of Medicine, St. Louis, MO, USA.
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Milne ML, Singh GK, Miller JG, Holland MR. Echocardiographic-based assessment of myocardial fiber structure in individual, excised hearts. ULTRASONIC IMAGING 2012; 34:129-141. [PMID: 22972911 DOI: 10.1177/0161734612455580] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The objective of this study was to assess the feasibility of using echocardiographic imaging as an approach for determining the myocardial fiber structure of intact, individual hearts. Seven formalin-fixed, ex vivo sheep hearts were imaged using a commercially available echocardiographic imaging system, and the intrinsic fiber structure for the reconstructed short-axis cross section was determined for a specific distance from the apex of each heart. Diffusion tensor magnetic resonance (DT-MR) images of each heart were acquired and fiber maps were created for comparison with the fiber structure obtained from the corresponding reconstructed echocardiographic images. These two methods of obtaining the fiber structure showed relatively good agreement, suggesting that measurements of fiber orientation for individual hearts can be derived from echocardiographic images. Further development of this method may provide a clinically useful approach for mapping the fiber orientation in individual patients over the heart cycle.
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Affiliation(s)
- Michelle L Milne
- Department of Physics, Washington University, St. Louis, MO, USA
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7
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Lloyd CW, Shmuylovich L, Holland MR, Miller JG, Kovács SJ. The diastolic function to cyclic variation of myocardial ultrasonic backscatter relation: the influence of parameterized diastolic filling (PDF) formalism determined chamber properties. ULTRASOUND IN MEDICINE & BIOLOGY 2011; 37:1185-95. [PMID: 21683506 PMCID: PMC3129365 DOI: 10.1016/j.ultrasmedbio.2011.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 04/30/2011] [Accepted: 05/05/2011] [Indexed: 05/30/2023]
Abstract
Myocardial tissue characterization represents an extension of currently available echocardiographic imaging. The systematic variation of backscattered energy during the cardiac cycle (the "cyclic variation" of backscatter) has been employed to characterize cardiac function in a wide range of investigations. However, the mechanisms responsible for observed cyclic variation remain incompletely understood. As a step toward determining the features of cardiac structure and function that are responsible for the observed cyclic variation, the present study makes use of a kinematic approach of diastolic function quantitation to identify diastolic function determinants that influence the magnitude and timing of cyclic variation. Echocardiographic measurements of 32 subjects provided data for determination of the cyclic variation of backscatter to diastolic function relation characterized in terms of E-wave determined, kinematic model-based parameters of chamber stiffness, viscosity/relaxation and load. The normalized time delay of cyclic variation appears to be related to the relative viscoelasticity of the chamber and predictive of the kinematic filling dynamics as determined using the parameterized diastolic filling formalism (with r-values ranging from .44 to .59). The magnitude of cyclic variation does not appear to be strongly related to the kinematic parameters.
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Affiliation(s)
- Christopher W. Lloyd
- Department of Physics, Washington University in Saint Louis, Saint Louis, Missouri
| | - Leonid Shmuylovich
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, Saint Louis, Missouri
| | - Mark R. Holland
- Department of Physics, Washington University in Saint Louis, Saint Louis, Missouri
| | - James G. Miller
- Department of Physics, Washington University in Saint Louis, Saint Louis, Missouri
| | - Sándor J. Kovács
- Cardiovascular Biophysics Laboratory, Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, Saint Louis, Missouri
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Anderson CC, Gibson AA, Schaffer JE, Peterson LR, Holland MR, Miller JG. Bayesian parameter estimation for characterizing the cyclic variation of echocardiographic backscatter to assess the hearts of asymptomatic type 2 diabetes mellitus subjects. ULTRASOUND IN MEDICINE & BIOLOGY 2011; 37:805-12. [PMID: 21439721 PMCID: PMC3078972 DOI: 10.1016/j.ultrasmedbio.2011.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 02/01/2011] [Accepted: 02/01/2011] [Indexed: 05/05/2023]
Abstract
Previous studies have shown that effective quantification of the cyclic variation of myocardial ultrasonic backscatter over the heart cycle might provide a non-invasive technique for identifying the early onset of cardiac abnormalities. These studies have demonstrated the potential for measurements of the magnitude and time delay of cyclic variation for identifying early onset of disease. The goal of this study was to extend this approach by extracting additional parameters characterizing the cyclic variation in an effort to better assess subtle changes in myocardial properties in asymptomatic subjects with type 2 diabetes. Echocardiographic images were obtained on a total of 43 age-matched normal control subjects and 100 type 2 diabetics. Cyclic variation data were generated by measuring the average level of ultrasonic backscatter over the heart cycle within a region of interest placed in the posterior wall of the left ventricle. Cyclic variation waveforms were modeled as piecewise linear functions, and quantified using a novel Bayesian parameter estimation method. Magnitude, rise time and slew rate parameters were extracted from models of the data. The ability of each of these parameters to distinguish between normal and type 2 diabetic subjects, and between subjects grouped by glycated hemoglobin (HbA1c) was compared. Results suggest a significant improvement in using measurements of the rise time and slew rate parameters of cyclic variation to differentiate (P < 0.001) the hearts of patients segregated based on widely employed indices of diabetic control compared to differentiation based on the magnitude of cyclic variation.
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Affiliation(s)
- Christian C Anderson
- Laboratory for Ultrasonics, Department of Physics, Washington University, St. Louis, MO, USA
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Zaidman CM, Connolly AM, Malkus EC, Florence JM, Pestronk A. Quantitative ultrasound using backscatter analysis in Duchenne and Becker muscular dystrophy. Neuromuscul Disord 2011; 20:805-9. [PMID: 20817454 DOI: 10.1016/j.nmd.2010.06.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Revised: 06/07/2010] [Accepted: 06/25/2010] [Indexed: 11/15/2022]
Abstract
Evaluation of ultrasound images of muscle with calibrated muscle backscatter (cMB) provides reproducible quantitative measurements of muscle pathology. Increased cMB is associated with greater muscle pathology. We used cMB to evaluate the severity of muscle pathology in 55 patients with Duchenne and Becker Muscular Dystrophy (D/BMD) compared to 77 controls. cMB was also compared to measurements of strength and function. cMB in DMD and BMD increased linearly with age and was higher than in controls when groups are compared. cMB increased twice as fast with age in DMD than in BMD. In DMD, cMB was higher with reduced function and strength. Ultrasound measurement of muscle pathology using cMB is a sensitive and objective quantitative technique for determining the severity of muscle pathology in dystrophinopathies. Longitudinal studies are required to determine the sensitivity of this measure to changes in pathology over time.
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Affiliation(s)
- Craig M Zaidman
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Lloyd CW, Holland MR, Miller JG. Improving the reproducibility of the cyclic variation of myocardial backscatter. ULTRASONIC IMAGING 2010; 32:243-254. [PMID: 21213569 DOI: 10.1177/016173461003200404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The goal of myocardial tissue characterization is to augment information provided by two- and three-dimensional echocardiographic imaging, Doppler blood flow and speckle- or Doppler-derived tissue motion. Tissue characterization based on the systematic variation ofbackscattered ultrasound during the cardiac cycle ('cyclic variation') appears to be effective in characterizing both focal and diffuse myocardial pathologies. Unfortunately, comparison ofresults from different laboratories is difficult because of a lack of consistency among the several reported methods of analyzing the cyclic variation data. The goals of the present work are to present an improved method of analysis and to demonstrate that apparent disagreements are attributable primarily to the distinct approaches employed by different investigators. The improved automated method for determining the magnitude of cyclic variation utilizes binomial smoothing and an average deviation method and was validated using data acquired from 23 patients. This method illustrates a systematic means for resolving differences between laboratories. This resolution facilitates future comparisons between the cyclic variation of myocardial backscatter and measurements derived, for example, from strain-related approaches.
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Affiliation(s)
- Christopher W Lloyd
- Department of Physics, Washington University in Saint Louis, Saint Louis, MO 63130, USA
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Holland MR, Gibson AA, Bauer AQ, Peterson LR, Schaffer JE, Bach RG, Cresci S, Miller JG. Echocardiographic tissue characterization demonstrates differences in the left and right sides of the ventricular septum. ULTRASOUND IN MEDICINE & BIOLOGY 2010; 36:1653-1661. [PMID: 20800946 PMCID: PMC2942980 DOI: 10.1016/j.ultrasmedbio.2010.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 06/30/2010] [Accepted: 07/06/2010] [Indexed: 05/29/2023]
Abstract
The left and right ventricular function of the heart are influenced by the complex structure of the ventricular septum. The cyclic variation of ultrasonic backscatter over the cardiac cycle is known to be sensitive to both structural and functional characteristics of the myocardium. The objective of this study was to investigate differences in the measured magnitude and normalized delay of cyclic variation between the left and right sides of the ventricular septum in normal adult subjects (N = 31). The measured mean magnitudes of cyclic variation were found to be 4.9 ± 0.4 dB and 2.4 ± 0.3 dB (mean ± SE; p < 0.0001) and the corresponding normalized delay values were found to be 0.94 ± 0.05 and 1.59 ± 0.12 (mean ± SE; p < 0.0001) for the left and right sides, respectively. These results show significant differences in the measured magnitude and normalized delay of cyclic variation between the left and right sides of the ventricular septum in normal subjects that appear consistent with predictions based on previously described models of cyclic variation of backscatter and reported measurements of transmural differences in strain properties of the septum.
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Gibson AA, Schaffer JE, Peterson LR, Bilhorn KR, Robert KM, Haider TA, Farmer MS, Holland MR, Miller JG. Quantitative analysis of the magnitude and time delay of cyclic variation of myocardial backscatter from asymptomatic type 2 diabetes mellitus subjects. ULTRASOUND IN MEDICINE & BIOLOGY 2009; 35:1458-67. [PMID: 19616360 PMCID: PMC2731824 DOI: 10.1016/j.ultrasmedbio.2009.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Revised: 02/06/2009] [Accepted: 04/10/2009] [Indexed: 05/05/2023]
Abstract
Early detection of diabetic patients at high risk for developing diabetic cardiomyopathy may permit effective intervention. The goal of this work is to determine whether measurements of the magnitude and time delay of cyclic variation of myocardial backscatter, individually and in combination, can be used to discriminate between subgroups of individuals including normal controls and asymptomatic type 2 diabetes subjects. Two-dimensional parasternal long-axis echocardiographic images of 104 type 2 diabetic patients and 44 normal volunteers were acquired. Cyclic variation data were produced by measuring the mean myocardial backscatter level within a region-of-interest in the posterior wall, and characterized in terms of the magnitude and normalized time delay. The cyclic variation parameters were analyzed using Bayes classification and a nonparametric estimate of the area under the receiver operating characteristic (ROC) curve to illustrate the relative effectiveness of using one or two features to segregate subgroups of individuals. The subjects were grouped based on glycated hemoglobin (HbA1c), the homeostasis model assessment for insulin resistance (HOMA-IR) and the ratio of triglyceride to high-density lipoprotein cholesterol (TG/HDL-C). Analyses comparing the cyclic variation measurements of subjects in the highest and lowest quartiles of HbA1c, HOMA-IR and TG/HDL-C showed substantial differences in the mean magnitude and normalized time delay of cyclic variation. Results show that analyses of the cyclic variation of backscatter in young asymptomatic type 2 diabetics may be an early indicator for the development of diabetic cardiomyopathy.
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Holland MR, Gibson AA, Kirschner CA, Hicks D, Ludomirsky A, Singh GK. Intrinsic myoarchitectural differences between the left and right ventricles of fetal human hearts: an ultrasonic backscatter feasibility study. J Am Soc Echocardiogr 2009; 22:170-6. [PMID: 19131208 DOI: 10.1016/j.echo.2008.11.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Embryologically, cardiac chambers differ in their morphologic and contractile properties from the beginning. We hypothesized that a noninvasive ultrasonic backscatter investigation might illustrate the fundamental differences in myocardial morphologic properties of the 2 ventricles during heart development. The goals of this investigation were to 1) explore the feasibility of measuring the magnitude of cyclic variation of ultrasonic backscatter from the left and right ventricular free walls of fetal hearts; 2) compare measurements of the magnitude of cyclic variation from the left and right sides of the heart; and 3) determine if the observed results are consistent with predictions relating the overall backscatter level and the magnitude of cyclic variation. METHODS Cyclic variation data from the left and right ventricular free walls were generated from analyses of the backscatter from echocardiographic images of 16 structurally normal fetal hearts at mid-gestation. RESULTS The magnitude of cyclic variation was found to be greater for the left ventricular free wall than for the right ventricular free wall (4.5 +/- 1.1 dB vs 2.3 +/- 0.9 dB, respectively; mean +/- standard deviation; P < .0001, paired t test). CONCLUSION Measurements of the cyclic variation of backscatter can be obtained from both the left and right sides of fetal hearts demonstrating a significant difference between the measured magnitude of cyclic variation in the left and right ventricular myocardium. This observation is consistent with predictions relating the overall backscatter level and the magnitude of cyclic variation. The results of this study suggest cyclic variation measurements may offer a useful approach for characterizing intrinsic differences in myocardial properties of the 2 ventricles in assessing fetal heart development.
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Zaidman CM, Holland MR, Anderson CC, Pestronk A. Calibrated quantitative ultrasound imaging of skeletal muscle using backscatter analysis. Muscle Nerve 2008; 38:893-8. [DOI: 10.1002/mus.21052] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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