1
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Sato Y, Maruyama A, Ichihashi K. Aging change of left ventricular function in children evaluated by acoustic quantification method. J Echocardiogr 2011; 9:97-102. [PMID: 27277176 DOI: 10.1007/s12574-011-0084-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 12/08/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND There are few reports about acoustic quantification (AQ) in the area of pediatrics. We aim to determine normal values of AQ analysis and investigate the aging change of left ventricular function in children. METHODS The subjects in this study included 137 patients (aged 29 days to 18 years) who had normal cardiac function and no cardiac load. None of the patients were receiving medical therapy. The instrument used was a PH-6500 (Philips, Andevor). Change of left ventricular area in short-axis view was detected by AQ analysis. From the mitral inflow, peak early (E) and peak late (A) diastolic velocities were measured, and E/A was calculated. RESULTS End-diastolic area (EDA) and end-systolic area (ESA) increased with age. Fractional area change (FAC) decreased with age. Peak ejection rate (PER) and peak rapid filling rate (PRFR) decreased with age up to 10 years. Atrial filling fraction (AFF) decreased and E/A increased with age up to 5 years. CONCLUSIONS Maturational or developmental alterations in LV diastolic properties were found up to 5 years old. AQ analysis is one of the useful indexes for investigating left ventricular diastolic function.
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Affiliation(s)
- Yuko Sato
- Department of Pediatrics, Saitama Medical Center Jichi Medical University, 1-847 Amanuma, Omiya, Saitama, 330-8503, Japan
| | - Asami Maruyama
- Department of Pediatrics, Saitama Medical Center Jichi Medical University, 1-847 Amanuma, Omiya, Saitama, 330-8503, Japan
| | - Ko Ichihashi
- Department of Pediatrics, Saitama Medical Center Jichi Medical University, 1-847 Amanuma, Omiya, Saitama, 330-8503, Japan.
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2
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Vilas-Boas F, Feitosa GS, Soares MBP, Pinho-Filho JA, Nascimento T, Barojas MM, Andrade MVS, Ribeiro-Dos-Santos R, Bocchi E. Invasive and noninvasive correlations of B-type natriuretic peptide in patients with heart failure due to Chagas cardiomyopathy. ACTA ACUST UNITED AC 2008; 14:121-6. [PMID: 18550922 DOI: 10.1111/j.1751-7133.2008.08166.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Heart failure due to Chagas cardiomyopathy (HFCC) differs from failure with other etiologies because of the occurrence of intense inflammatory infiltrate and right ventricle compromise. This article investigates correlations of B-type natriuretic peptide (BNP) levels with parameters of severity in HFCC. Twenty-eight patients and 8 normal controls underwent heart catheterization and clinical and laboratory analyses. BNP levels were higher in patients with HFCC (P<.0001) and correlated with New York Heart Association (NYHA) class; right atrial pressure; wedge pressure; cardiac output; levels of serum sodium, hemoglobin, urea, and tumor necrosis factor-alpha; and ejection fraction. Interferon-gamma and transforming growth factor-beta did not correlate with BNP level. The authors conclude that BNP levels are elevated in patients experiencing HFCC, irrespective of NYHA class, and that the occurrence of HFCC correlates with severity of disease.
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Affiliation(s)
- Fábio Vilas-Boas
- Heart Failure Clinics and Academic Research Department of Santa Izabel Hospital, Salvador, BA, Brazil.
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3
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Zamudio AC, Candia OA, Kong CW, Wu B, Gerometta R. Surface change of the mammalian lens during accommodation. Am J Physiol Cell Physiol 2008; 294:C1430-5. [PMID: 18385280 DOI: 10.1152/ajpcell.90623.2007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Classical theories suggest that the surface area of the crystalline lens changes during accommodation while the lens volume remains constant. Our recent work challenged this view by showing that the lens volume decreases as the lens flattens during unaccommodation. In this paper we investigate 1) the magnitude of changes in the surface of the in vitro isolated cow lens during simulated accommodation, as well as that of human lens models, determined from lateral photographs and the application of the first theorem of Pappus; and 2) the velocity of the equatorial diameter recovery of prestretched cow and rabbit lenses by using a custom-built software-controlled stretching apparatus synchronized to a digital camera. Our results showed that the in vitro cow lens surface changed in an unexpected manner during accommodation depending on how much tension was applied to flatten the lens. In this case, the anterior surface initially collapsed with a reduction in surface followed by an increase in surface, when the stretching was applied. In the human lens model, the surface increased when the lens unaccommodated. The lens volume always decreases as the lens flattens. An explanation for the unexpected surface change is presented and discussed. Furthermore, we determined that the changes in lens volume, as reflected by the speed of the equatorial diameter recovery in in vitro cow and rabbit lenses during simulated accommodation, occurred within a physiologically relevant time frame (200 ms), implying a rapid movement of fluid to and from the lens during accommodation.
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Affiliation(s)
- Aldo C Zamudio
- Department of Ophthalmology, Mount Sinai School of Medicine, New York, NY 10029, USA
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4
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Abstract
This article describes the obstacles to stress echocardiographic interpretation, and reviews the techniques currently available that offer a more objective approach to stress wall motion analysis than the conventional visual methodology. These techniques include Doppler-based methods, such as myocardial Doppler velocity and strain rate imaging, as well as automated border detection techniques, such as acoustic quantification and color kinesis.
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Affiliation(s)
- Jeanne M DeCara
- Noninvasive Cardiac Imaging Laboratories, Department of Medicine, University of Chicago Medical Center, Chicago, Illinois 60637, USA.
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5
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Sugioka K, Hozumi T, Yagi T, Yamamuro A, Akasaka T, Takeuchi K, Homma S, Yoshida K, Yoshikawa J. Automated quantification of left ventricular function by the automated contour tracking method. Echocardiography 2003; 20:313-8. [PMID: 12848874 DOI: 10.1046/j.1540-8175.2003.03036.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The automated contour tracking (ACT) method has been developed for the automated measurement of area volume using the energy minimization method without tracing a region of interest. The purpose of this study was to compare the ACT method and left ventriculography (LVG) for the measurement of left ventricular (LV) function in the clinical setting. An apical four-chamber view was visualized by two-dimensional echocardiography and recorded for off-line analysis in 14 patients with high-quality images who underwent LVG. The ACT method automatically traces the endocardial border from the recorded images and calculates LV volumes (end-diastole and end-systole) and ejection fraction (EF). Both ACT and LVG were compared by linear regression analysis for the measurement of EF. EF determined by the ACT method agreed well with that by LVG (r = 0.96, y = 0.94x + 4.6, standard error of the estimate = 3.9%). The mean difference between the ACT and LVG was -1.4%+/- 7.3%. In conclusion, the ACT method is reliable for noninvasive estimation of EF in high-quality images. This suggests that this new technique may be useful in the automated quantification of LV function.
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Affiliation(s)
- Kenichi Sugioka
- Division of Cardiology, Department of Medicine, Columbia University, New York, New York, USA
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6
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Caiani EG, Porta A, Baselli G, Turiel M, Muzzupappa S, Pagani M, Malliani A, Cerutti S. Analysis of cardiac left-ventricular volume based on time warping averaging. Med Biol Eng Comput 2002; 40:225-33. [PMID: 12043805 DOI: 10.1007/bf02348129] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cardiac left-ventricular (LV) volume signal, obtained by acoustic quantification, is affected by noise and respiratory modulation, resulting in a large beat-to-beat variability that affects the computation of LV function indices. A new method is proposed to improve the evaluation of LV indices by applying a signal averaging technique based on dynamic time warping to consecutive LV volume waveforms. Volume signals obtained from ten normal young (NY) subjects (mean age +/- SD: 25+/-5 years) were used to evaluate the performance of this algorithm. To evaluate its clinical utility, the effects of ageing and pharmacologically induced changes on LV function were assessed by studying, respectively, ten normal (N) adult subjects (age 64+/-8 years) and ten patients with dilated cardiomyopathy during a control and low-dose dobutamine (10 microg kg(-1) min(-1)) study. Indices of LV function were highly consistent, with a variability of less than 8%, even when only 16 beats were averaged, independently of their selection inside the whole recording. When compared with beat-to-beat measures, the averaging of 16 beats significantly reduced (by more than 50%) the interbeat variability of all indexes. Expected alterations in both diastolic and systolic function were evidenced both with ageing (peak filling atrial contraction and ejection rates: from 275+/-77 mls(-1), 76+/-30 ml s(-1) 230+/-70 mls(-1), respectively, in NY, to 160+/-33 mls(-1), 125+/-39 mls(-1), 163+/-54 mls(-1) in N) and with dobutamine (peak filling and ejection rates from 160+/-72 mls(-1) and 183+/-86 mls(-1) respectively, in control, to 253+/-75 mls(-1) and 251+/-105 mls(-1) with dobutamine). Signal averaging with time warping allows fast and improved assessment of LV function.
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Affiliation(s)
- E G Caiani
- Dipartimento di Bioingegneria, Politecnico di Milano, Milan, Italy.
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7
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Bashir M, Asher CR, Schaffer K, Murray RD, Apperson-Hansen C, Jasper SE, Thomas JD, Klein AL. Left atrial appendage spontaneous echo contrast in patients with atrial arrhythmias using integrated backscatter and transesophageal echocardiography. Am J Cardiol 2001; 88:923-7, A9. [PMID: 11676967 DOI: 10.1016/s0002-9149(01)01911-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- M Bashir
- Division of Cardiology, University of California, Irvine, USA
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8
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Mor-Avi V, Spencer K, Gorcsan J, Demaria A, Kimball T, Monaghan M, Perez J, Sun JP, Weinert L, Bednarz J, Collins K, Edelman K, Kwan OL, Glascock B, Hancock J, Baumann C, Thomas J, Lang R. Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 2000; 279:H2464-76. [PMID: 11045984 DOI: 10.1152/ajpheart.2000.279.5.h2464] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Our goal was to establish normal values for quantitative color kinesis indexes of left ventricular (LV) wall motion over a wide range of ages, which are required for objective diagnosis of regional systolic and diastolic dysfunction. Color-encoded images were obtained in 194 normal subjects (95 males, 99 females, age 2 mo to 79 yr) in four standard views. Quantitative indexes of magnitude and timing of systolic and diastolic function were studied for age- and gender-related differences. Normal limits of all ejection and filling indexes were in a narrow range (< or =25% of the mean), with no major gender-related differences. Despite invariable ejection fractions, both peak filling and ejection rates decreased with age (30 and 20%, correspondingly) with a concomitant increase in mean filling and ejection times, resulting in five- and twofold increases in the late to early filling and ejection ratios, correspondingly. Diastolic asynchrony increased with age (from 4.7 +/- 2.0 to 6.4 +/- 3.2 from the 2nd to 7th decade). The normal values of color kinesis indexes should allow objective detection of regional LV systolic and diastolic dysfunction.
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Affiliation(s)
- V Mor-Avi
- The University of Chicago, Chicago, Illinois 60637, USA.
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9
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Caiani EG, Turiel M, Muzzupappa S, Porta A, Baselli G, Pagani M, Cerutti S, Malliani A. Evaluation of respiratory influences on left ventricular function parameters extracted from echocardiographic acoustic quantification. Physiol Meas 2000; 21:175-86. [PMID: 10720013 DOI: 10.1088/0967-3334/21/1/321] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This study was designed to assess, using the echocardiographic acoustic quantification technique, the influence of respiration on left ventricular (LV) function and its modifications connected with the ageing process, quantifying in a non-invasive way the respiratory contribution to the LV volume variability. An automated algorithm is applied to extract the beat-to-beat measurements of LV function parameters from the LV volume signal, obtained from recordings lasting a few minutes. Mean values, amount of variability and spectral content were studied in a population of 17 normal young (mean age 25 +/- 1 years) and 12 normal old (mean age 64 +/- 2 years) subjects. Mean values of the beat-to-beat measurements of LV function parameters were able to point out alterations connected with the ageing process in peak filling rate, peak atrial filling rate and peak ejection rate. Spectral analysis, applied to the extracted variability series, displayed a predominance of the high-frequency (HF) component corresponding to respiration in all LV function parameters; moreover, age related changes of HF variability were observed in peak ejection rate. The HF power spectrum component of beat to beat series extracted from the LV signal can provide a non-invasive assessment of the fluctuations in ventricular parameters associated with respiration.
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Affiliation(s)
- E G Caiani
- Dipartimento di Bioingegneria, Politecnico di Milano, Milan, Italy
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10
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Chuang ML, Beaudin RA, Riley MF, Mooney MG, Manning WJ, Hibberd MG, Douglas PS. Impact of on-line endocardial border detection on determination of left ventricular volume and ejection fraction by transthoracic 3-dimensional echocardiography. J Am Soc Echocardiogr 1999; 12:551-8. [PMID: 10398913 DOI: 10.1016/s0894-7317(99)70002-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
This study was performed to determine whether use of on-line automated border detection (ABD) could reduce data analysis time for 3-dimensional echocardiography (3DE) while maintaining accuracy of 3DE in measures of left ventricular (LV) volumes and ejection fraction (EF). The study proceeded in 2 phases. In the validation phase, 20 subjects were examined with the use of 3DE and of monoplane 2-dimensional (2D) ABD. Results were compared with the reference standard of magnetic resonance imaging (MRI). In the test phase, 20 subjects underwent two 3DE studies (once with images optimized for visual border definition and once with images optimized for ABD border tracking) and a conventionally used 2D ABD study. For 3DE, volumes and EF were determined with the use of manually traced borders and ABD. Analysis times were recorded with a digital stopwatch. In the validation phase, 3DE and MRI results correlated very well (r = 0.99) without systematic differences. Comparison of 2D ABD with MRI showed good correlation for LV volumes (r >/= 0.90) and EF (r = 0.85) despite significant underestimation. For the test phase, Acoustic Quantification-optimized 3-dimensional datasets underestimated end-diastolic volume and EF relative to visually optimized 3-dimensional datasets regardless of whether borders were hand-traced or ABD was used. However, correlations ranged from r = 0.96 to r = 0.98 for LV volumes and 0.88 to 0.91 for LV EF and were superior to those for 2D ABD. Data analysis times decreased moderately with the use of ABD, but scan times increased; total study times were unchanged. Use of on-line ABD with 3DE reduces data analysis time and is more accurate than conventional monoplane 2D ABD but results in underestimation of LV volumes and EF. Additional automated postprocessing techniques may be required to obtain accurate measures, consistently using 3DE in conjunction with on-line ABD.
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Affiliation(s)
- M L Chuang
- Charles A. Dana Research Institute and the Harvard Thorndike Laboratory of the Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA
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11
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Pérez JE. Online Quantification of Left Ventricular Function: Correlation with Various Imaging Modalities. Echocardiography 1999; 16:43-49. [PMID: 11175122 DOI: 10.1111/j.1540-8175.1999.tb00785.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The need for more objectively quantifiable evaluation of the left ventricular function, obtainable on line with echocardiography, was fulfilled through modifications of integrated backscatter imaging to permit real-time differentiation of the endocardium and the blood pool area in every image frame. Operator-guided study of individual cardiac chambers permitted instantaneous measurement of chamber areas in either the systole or diastole, with resulting physiologically meaningful recordings that relate to cardiac function. Validation studies by various approaches suggest that the methodology is clinically relevant, and further improvements in design will sharpen its applicability in the future.
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Affiliation(s)
- Julio E. Pérez
- Cardiovascular Division, Washington University, 660 South Euclid, Box 8086, St. Louis, MO 63110
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12
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Abstract
We briefly review previously published work based on the uses of acoustic quantification (AQ) or validation of this technology. We also discuss the limitations of AQ in a critical review of the literature, including operator dependency, signal noise, and low temporal resolution. We describe some enhancements made to AQ software to address these limitations and improve the accuracy of this technique, including digital beam processing, harmonic imaging, and signal averaging. Several anticipated applications are also briefly described for those interested in the future development of this technology. These future applications include noninvasive long-term monitoring of ventricular function and objective assessment of regional ventricular wall motion in two and three dimensions.
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Affiliation(s)
- Victor Mor-Avi
- The University of Chicago Medical Center, 5841 S. Maryland Ave., M.C. 5084, Chicago, IL 60637
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13
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Vandenberg BF, Cardona H, Miller JG, Burns TL, Skorton DJ, Pérez JE. Estimation of Left Ventricular Ejection Fraction by Semiautomated Edge Detection. Echocardiography 1998; 15:713-720. [PMID: 11175103 DOI: 10.1111/j.1540-8175.1998.tb00671.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Left ventricular (LV) volume and ejection fraction estimation from two-dimensional echocardiograms requires off-line analysis and time-consuming manual tracing. LV volumes may be estimated on-line with a semiautomated edge detection echocardiographic system [also known as acoustic quantification (AQ)], but there are few data that compare volumes obtained from the AQ method with volumes derived from off-line manual tracing of conventional two-dimensional echocardiograms. Echocardiograms were performed in 48 patients at two medical centers. LV volumes were measured from the apical view with the method of discs and area-length formulae and from the parasternal short-axis view with the modified ellipsoid model. Based on the criterion of >/=75% endocardial visualization, 25 (52%) of the short-axis views and 14 (29%) of the apical views were analyzed by a single investigator. End-diastolic and end-systolic LV volumes derived on line with the AQ system showed a very strong linear association with off-line, manually traced volumes (r = 0.96-0.99). Correlations for ejection fraction also were strong (r = 0.90-0.96). End-diastolic and end-systolic LV volumes, measured from the apical views, were underestimated by the AQ method. However, because the error was in the same direction, ejection fractions measured with the AQ system and by manual tracing of conventional echocardiograms were similar. Estimation of ejection fraction using a semiautomated edge detection echocardiographic system is a promising method for noninvasive evaluation of systolic function in carefully selected patients.
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14
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Mor-Avi V, Vignon P, Bales AC, Spencer KT, Lang RM. Acoustic quantification indexes of left ventricular size and function: effects of signal averaging. J Am Soc Echocardiogr 1998; 11:792-802. [PMID: 9719091 DOI: 10.1016/s0894-7317(98)70054-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The aim of this study was to evaluate the clinical utility of using signal-averaged acoustic quantification (SAAQ) waveforms for improved assessment of left ventricular (LV) size and function. METHODS AND RESULTS Four separate protocols were performed in 47 subjects. SAAQ waveforms were used to assess alterations in LV function induced by dobutamine (15 microg/kg per minute) and esmolol (200 microg/kg per minute) in eight normal subjects. Subsequently, we analyzed SAAQ waveforms obtained in 12 patients with LV dysfunction secondary to dilated cardiomyopathy and 12 age-matched normal subjects. Finally, we developed computer software for monitoring of LV function on the basis of continuous acquisition and repeated analysis of SAAQ waveforms. We compared the interbeat variability in indexes of LV function obtained from raw AQ and SAAQ during 10 minutes of steady-state monitoring in eight patients undergoing transesophageal echocardiography. The feasibility of long-term monitoring in the intensive care setting was then studied in seven patients undergoing abdominal surgery. Our analysis tracked variations in LV function induced by dobutamine and esmolol. Significant differences in all measured indexes were found between normal subjects and patients with dilated cadiomyopathy. Signal averaging during steady-state monitoring significantly reduced the interbeat variability of all indexes (21% to 42%). In the operating room, the SAAQ monitoring system tracked hemodynamic changes in close agreement with invasive measurements. CONCLUSIONS SAAQ allows fast and easy quantification of LV function and can track hemodynamic trends in the operating room setting.
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Affiliation(s)
- V Mor-Avi
- Department of Medicine, The University of Chicago Medical Center, Illinois 60637, USA
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15
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Cheesman MG, Leech G, Chambers J, Monaghan MJ, Nihoyannopoulos P. Central role of echocardiography in the diagnosis and assessment of heart failure. British Society of Echocardiography. HEART (BRITISH CARDIAC SOCIETY) 1998; 80 Suppl 1:S1-5. [PMID: 10078068 PMCID: PMC1766493 DOI: 10.1136/hrt.80.2008.1s] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- M G Cheesman
- Department of Medicine for the Elderly, Southmead Hospital, Westbury-on-Trym, Bristol, UK
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16
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Sapra R, Singh B, Thatai D, Prabhakaran D, Malhotra A, Manchanda SC. Critical appraisal of left ventricular function assessment by the automated border detection method on echocardiography. Is it good enough? Int J Cardiol 1998; 65:193-9. [PMID: 9706816 DOI: 10.1016/s0167-5273(98)00111-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Many studies have attempted to validate the echocardiographic automated border detection (ABD) method for assessing left ventricular ejection fraction (LVEF) by comparing it with various echocardiographic and non-echocardiographic standards. The main basis of assessing its accuracy has been the coefficient of correlation. The fallacy of using coefficient of correlation for assessing agreement between two methods of measurement has been well emphasized in the literature. In the present study we used the Bland and Altman test for testing the accuracy of the ABD method. We compared the ABD method for LVEF assessment with the manual edge detection technique on echocardiography and with radionuclide ventriculography in 34 patients. The majority of patients (76%) had regional wall motion abnormality. The ABD method could be adequately performed in 25 (74%) patients. LVEF was significantly underestimated by the ABD method with very wide limits of agreement when compared with radionuclide ventriculography and the manual edge detection technique (-9.2+/-21.7 and -2.7+/-18.4 respectively, mean error+/-2 standard deviations). Stated simply, the ABD method could overestimate LVEF by 12.5 and 15.7 or underestimate by 30.9 and 21.1 when compared with radionuclide ventriculography and manual edge detection technique, respectively. This large error is by no means acceptable for clinical purposes. It is concluded that at the present stage, the ABD method cannot replace radionuclide ventriculography and manual edge detection technique for assessing LVEF.
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Affiliation(s)
- R Sapra
- Department of Cardiology Cardiothoracic Centre, All India Institute of Medical Sciences, New Delhi
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17
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Bednarz J, Vignon P, Mor-Avi V, Weinert L, Koch R, Spencer K, Lang RM. Color Kinesis: Principles of Operation and Technical Guidelines. Echocardiography 1998; 15:21-34. [PMID: 11175007 DOI: 10.1111/j.1540-8175.1998.tb00574.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Color kinesis is a new echocardiographic technique that aids in the assessment of global and regional left ventricular performance during either systole or diastole. Color kinesis uses automated border detection technology based on backscatter data to display both the magnitude and timing of endocardial motion in real time. The color kinesis display superimposes a color overlay on the two-dimensional echocardiographic image; the number of color pixels represents the magnitude of endocardial motion, while the different colors represent the timing of endocardial motion according to a predefined color scheme. Because color kinesis is an operator-dependent technique, the steps involved in performing a technically adequate study will be reviewed as well as the pitfalls and technical limitations. The potential clinical applications of color kinesis will also be discussed.
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Affiliation(s)
- James Bednarz
- Noninvasive Cardiac Imaging Laboratory, Section of Cardiology, University of Chicago Hospitals, 5841 S. Maryland Avenue, MC5084, Chicago, IL 60637. ,
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18
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Rumberger JA, Behrenbeck T, Bell MR, Breen JF, Johnston DL, Holmes DR, Enriquez-Sarano M. Determination of ventricular ejection fraction: a comparison of available imaging methods. The Cardiovascular Imaging Working Group. Mayo Clin Proc 1997; 72:860-70. [PMID: 9294535 DOI: 10.4065/72.9.860] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Knowledge of left ventricular ejection fraction has been shown to provide diagnostic and prognostic information in patients with known or suspected heart disease. In clinical practice, the ejection fraction can be determined by using one of the five currently available imaging techniques: contrast angiography, echocardiography, radionuclide techniques of blood pool and first pass imaging, electron beam computed tomography, and magnetic resonance imaging. In this review, we discuss the clinical application as well as the advantages and disadvantages of each of these methods as it relates to determination of ventricular ejection fraction.
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Affiliation(s)
- J A Rumberger
- Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic Rochester, Minnesota 55905, USA
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19
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Devereux RB, Pini R, Aurigemma GP, Roman MJ. Measurement of left ventricular mass: methodology and expertise. J Hypertens 1997; 15:801-9. [PMID: 9280201 DOI: 10.1097/00004872-199715080-00002] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The strong relation between increased left ventricular mass and cardiovascular events makes accurate measurement of left ventricular mass a high priority, especially in patients with hypertension. M-mode echocardiography is used most widely to measure left ventricular mass because of its wide availability, moderate expense, anatomic and prognostic validation and lack of radiation or claustrophobia; however, this technique is expertise-dependent and may give erroneous results in distorted ventricles. Two-dimensional and especially three-dimensional echocardiography increase the precision with which left ventricular mass is measured but they are more time-consuming and difficult to perform on a large scale. Magnetic resonance imaging provides highly accurate left ventricular mass measurements and permits tissue imaging but its use is limited by expensive, fixed facilities and claustrophobia. Cine computed X-ray tomography also measures left ventricular mass accurately and permits perfusion assessment with contrast injection but it involves radiation and the use of fixed facilities of limited availability. Understanding the strengths and limitations of available techniques can facilitate selection of the most appropriate method to measure left ventricular mass in a particular setting.
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Kraut EJ, Owings JT, Anderson JT, Hanowell L, Moore P. Right ventricular volumes overestimate left ventricular preload in critically ill patients. THE JOURNAL OF TRAUMA 1997; 42:839-45; discussion 845-6. [PMID: 9191665 DOI: 10.1097/00005373-199705000-00014] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Studies have shown right ventricular end-diastolic volume (RVEDV) to be a more accurate estimate of left ventricular preload than pulmonary artery wedge pressure. We prospectively evaluated the ability of RVEDV to predict left ventricular end-diastolic volume (LVEDV) in critically ill patients. METHODS Thirty critically ill patients in the surgical intensive care unit underwent concurrent measurement of RVEDV and LVEDV. RVEDV was measured using a residual fraction Swan-Ganz catheter (RF Swan). LVEDV was measured using transesophageal echocardiography with acoustic quantification. Intracardiac, intra-abdominal, and ventilatory pressures were also measured. RESULTS RVEDV as measured by the RF Swan was significantly larger (by a factor of 2) than LVEDV (p < 0.0001 analysis of variance). However, the RVEDV and LVEDV were strongly correlated (r = 0.71, p < 0.0001, Pearson's correlation). CONCLUSIONS RVEDV from the RF Swan markedly overestimated left ventricular preload. If RVEDV is used as an absolute value for determining preload, patients may be underresuscitated. Transesophageal echocardiography in conjunction with RF Swan can be used to more accurately determine preload and cardiac performance than RF Swan alone in critically ill patients.
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Affiliation(s)
- E J Kraut
- Department of Surgery, University of California, Davis Medical Center, Sacramento 95817-2214, USA
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21
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Boppart SA, Tearney GJ, Bouma BE, Southern JF, Brezinski ME, Fujimoto JG. Noninvasive assessment of the developing Xenopus cardiovascular system using optical coherence tomography. Proc Natl Acad Sci U S A 1997; 94:4256-61. [PMID: 9113976 PMCID: PMC20709 DOI: 10.1073/pnas.94.9.4256] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Studies investigating normal and abnormal cardiac development are frequently limited by an inability to assess cardiovascular function within the intact organism. In this work, optical coherence tomography (OCT), a new method of micron-scale, noninvasive imaging based on the measurement of backscattered infrared light, was introduced for the high resolution assessment of structure and function in the developing Xenopus laevis cardiovascular system. Microstructural details, such as ventricular size and wall positions, were delineated with OCT at 16-microm resolution and correlated with histology. Three-dimensional representation of the cardiovascular system also was achieved by repeated cross-sectional imaging at intervals of 25 microm. In addition to structural information, OCT provides high speed in vivo axial ranging and imaging, allowing quantitative dynamic activity, such as ventricular ejection fraction, to be assessed. The sensitivity of OCT for dynamic assessment was demonstrated with an inotropic agent that altered cardiac function and dimensions. Optical coherence tomography is an attractive new technology for assessing cardiovascular development because of its high resolution, its ability to image through nontransparent structures, and its inexpensive portable design. In vivo and in vitro imaging are performed at a resolution approaching that of histopathology without the need for animal killing.
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Affiliation(s)
- S A Boppart
- Department of Electrical Engineering and Computer Science, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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22
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Vandenberg BF, Oren RM, Lewis J, Aeschilman S, Burns TL, Kerber RE. Evaluation of color kinesis, a new echocardiographic method for analyzing regional wall motion in patients with dilated left ventricles. Am J Cardiol 1997; 79:645-50. [PMID: 9068525 DOI: 10.1016/s0002-9149(96)00832-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The recently developed echocardiographic technology of color kinesis (CK) displays endocardial motion in color layers on a single end-systolic 2-dimensional echocardiographic frame. Previous work using this method is promising for quantitation of regional function, but there is limited experience in patients with severely reduced left ventricular function. Twenty patients (age 59 +/- 10 years) with dilated cardiomyopathy (left ventricular ejection fraction 22 +/- 8%) underwent CK imaging. Endocardial motion was quantitated by measuring the distance of endocardial motion during the systolic interval and also by calculating the endocardial velocity. CK measurements were compared among 4 wall motion grades (i.e., normal, hypokinetic, akinetic, and dyskinetic) assessed by qualitative wall motion scoring. There was a significant overall difference (p < 0.0001) in the mean systolic endocardial inward motion (i.e., contraction) and outward motion (i.e., expansion) among wall motion grades. The mean endocardial outward distance was significantly greater for the dyskinetic segments than for the other grades (p < 0.001). There were also differences in the mean velocity of endocardial motion among the wall motion grades. In the presence of left bundle branch block, there was no difference in the mean endocardial inward distance of the hypokinetic, akinetic, and dyskinetic septal segments. We conclude that in the absence of left bundle branch block, normal, hypokinetic, akinetic, and dyskinetic ventricular wall segments may be distinguished in patients with dilated cardiomyopathy on the basis of endocardial motion measured with CK.
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MESH Headings
- Bundle-Branch Block/diagnostic imaging
- Bundle-Branch Block/physiopathology
- Cardiac Output, Low/diagnostic imaging
- Cardiac Output, Low/physiopathology
- Cardiomyopathy, Dilated/diagnostic imaging
- Cardiomyopathy, Dilated/physiopathology
- Dilatation, Pathologic/diagnostic imaging
- Dilatation, Pathologic/physiopathology
- Echocardiography, Doppler, Color/methods
- Endocardium/diagnostic imaging
- Endocardium/physiopathology
- Evaluation Studies as Topic
- Female
- Heart Diseases/diagnostic imaging
- Heart Diseases/physiopathology
- Heart Septum/diagnostic imaging
- Heart Septum/physiopathology
- Heart Ventricles/diagnostic imaging
- Heart Ventricles/physiopathology
- Humans
- Male
- Middle Aged
- Myocardial Contraction
- Stroke Volume
- Systole
- Ventricular Dysfunction, Left/diagnostic imaging
- Ventricular Dysfunction, Left/physiopathology
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Affiliation(s)
- B F Vandenberg
- University of Iowa College of Medicine, Department of Internal Medicine, Iowa City 52242, USA
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23
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Chandra S, Bahl VK, Reddy SC, Bhargava B, Malhotra A, Wasir HS. Comparison of echocardiographic acoustic quantification system and radionuclide ventriculography for estimating left ventricular ejection fraction: validation in patients without regional wall motion abnormalities. Am Heart J 1997; 133:359-63. [PMID: 9060807 DOI: 10.1016/s0002-8703(97)70233-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Echocardiographic automated border detection of blood-endocardium interface is made on the basis of the principle of acoustic quantification. The automated border system is capable of providing on-line left ventricular (LV) cavity area and function. Recently, ABD algorithms have been devised to estimate LV volume on line from a long-axis image, calculated by established area-length method or Simpson's formula. To test the clinical validity of this newly developed echocardiographic method, LV volumes and ejection fraction measured by real-time acoustic quantification were compared with radionuclide ejection fraction in 24 subjects on the same day. Patients were included in the study if > or = 75% of their endocardium was visualized with conventional two-dimensional echocardiography. Sixteen (66%) of 24 patients had a technically adequate conventional echocardiogram with a broad range of ventricular dimensions and systolic function. None of the study patients had regional wall motion abnormalities. Echocardiographic measurements were obtained from the LV apical four-chamber, long-axis view. Ejection fraction, determined by the acoustic quantification and by radionuclide ventriculography, showed a strong linear relation (r = 0.92, standard error of the estimate = 4.4, p < 0.05). However, acoustic quantification overestimated the radionuclide ejection fraction with rather wide limits of agreement (3.8% +/- 16.4%; bias +/- 2 SD). Thus echocardiographic automated border detection technique is a reasonably accurate method for on-line assessment of LV function.
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Affiliation(s)
- S Chandra
- Department of Cardiology, All India Institute of Medical Sciences, New Delhi, India
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24
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25
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Schwartz SL, Cao QL, Vannan MA, Pandian NG. Automatic backscatter analysis of regional left ventricular systolic function using color kinesis. Am J Cardiol 1996; 77:1345-50. [PMID: 8677877 DOI: 10.1016/s0002-9149(96)00203-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Assessment of regional wall motion by 2-dimensional echocardiography can be performed by either semiquantitative wall motion scoring or by quantitative analysis. The former is subjective and requires expertise. Quantitative methods are too time-consuming for routine use in a busy clinical laboratory. Color kinesis is a new algorithm utilizing acoustic backscatter analysis. It provides a color encoded map of endocardial motion in real time. In each frame a new color layer is added; the thickness of the color beam represents endocardial motion during that frame. The end-systolic image has multiple color layers, representing regional and temporal heterogeneity of segmental motion. The purpose of this study was to validate the use of color kinesis for semiquantitative analysis of regional left ventricular systolic function and quantitatively in measurement of endocardial excursion. Semiquantitative wall motion scoring was performed in 18 patients using both 2-dimensional echo and color kinesis. Scoring was identical in 74% of segments; there was 84% agreement in definition of normal vs. abnormal. There was less interobserver variability in wall motion scoring using color kinesis. Endocardial excursion was quantified in 21 patients. 70% of the imaged segments were suitable for analysis. Correlation between 2-dimensional echocardiographic measurements and color kinesis was excellent, r = 0.87. The mean difference in excursion as measured by the 2 methods was -0.05 +/- 2.0 mm. In conclusion, color kinesis is a useful method for assessing regional contraction by displaying a color map of systolic endocardial excursion. This algorithm may improve the confidence and accuracy of assessment of segmental ventricular function by echocardiographic methods.
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Affiliation(s)
- S L Schwartz
- Department of Medicine, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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26
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Keren A, DeAnda A, Komeda M, Tye T, Handen CR, Daughters GT, Ingels NB, Miller C, Popp RL, Nikolic SD. Pitfalls in creation of left atrial pressure-area relationships with automated border detection. J Am Soc Echocardiogr 1995; 8:669-78. [PMID: 9417210 DOI: 10.1016/s0894-7317(05)80381-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Creation of pressure-area relationships (loops) with automated border detection (ABD) involves correction for the variable inherent delay in the ABD signal relative to the pressure recording. This article summarizes (1) the results of in vitro experiments performed to define the range of, and factors that might influence, the ABD delay; (2) the difficulties encountered in evaluating a thin-walled structure like the left atrium in the dog model; and (3) the solutions to some of the difficulties found. The in vitro experiments showed that the ABD delay relative to high-fidelity pressure recordings ranges from 20 to 34 msec and 35 to 57 msec at echocardiographic frame rates of 60/sec and 33/sec, respectively. The delay was not influenced significantly by the type of transducer used, distance from the target area, or size of the target area. The delay in the ABD signal, relative to the echocardiographic image, ranges from nil to less than one frame duration, whereas it is delayed one to two frame durations relative to the electrocardiogram processed by the imaging system. In the dog model, inclusion of even small areas outside the left atrium rendered curves with apparent physiologic contour but inappropriately long delays of 90 to 130 msec. To exclude areas outside the left atrial cavity, time-gain compensation and lateral gain compensation were used much more extensively than during left ventricular ABD recording. By changing the type of sonomicrometers used in our experiments, we were able to record simultaneously ABD and ultrasonic crystal data. However, both spontaneous contrast originating from a right-sided heart bypass pump and electronic noise from the eletrocautery severely interferred with ABD recording.
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Affiliation(s)
- A Keren
- Division of Cardiovascular Medicine, Stanford University School of Medicine, California, USA
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27
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Bednarz JE, Marcus RH, Lang RM. Technical guidelines for performing automated border detection studies. J Am Soc Echocardiogr 1995; 8:293-305. [PMID: 7640023 DOI: 10.1016/s0894-7317(05)80040-9] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- J E Bednarz
- Department of Medicine, University of Chicago Hospitals, IL 60637, USA
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28
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Sun JP, Stewart WJ, Yang XS, Lee KS, Sheldon WS, Thomas JD. Automated echocardiographic quantification of left ventricular volumes and ejection fraction: validation in the intensive care setting. J Am Soc Echocardiogr 1995; 8:29-36. [PMID: 7710748 DOI: 10.1016/s0894-7317(05)80355-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To validate automated boundary detection measurements of left ventricular volumes, cardiac output, and ejection fraction, we studied 50 patients in the intensive care unit. End-diastolic volume, end-systolic volume, and ejection fraction were calculated by automated boundary detection and compared with two-dimensional echocardiographic images. Automated boundary detection-derived cardiac output was compared with thermodilution measurements and Doppler calculations of flow through the aortic and pulmonic valves. Automated boundary detection agreed well with two-dimensional measurements for end-diastolic volume (r = 0.98), end-systolic volume (r = 0.98), and ejection fraction (r = 0.91). Cardiac output derived from automated boundary detection correlated with two-dimensional echocardiographic measurements (r = 0.84), thermodilution (r = 0.83), aortic valve Doppler (r = 0.75), and pulmonic valve Doppler (r = 0.60). Automated boundary detection measurements of left ventricular volumes, ejection fraction, and derived cardiac output are feasible in patients in intensive care units. This method yields rapid, accurate result compared with thermodilution, two-dimensional images, and Doppler measurements.
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Affiliation(s)
- J P Sun
- Department of Cardiology, Cleveland Clinic Foundation, OH 44195, USA
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29
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Yvorchuk KJ, Davies RA, Chan KL. Measurement of left ventricular ejection fraction by acoustic quantification and comparison with radionuclide angiography. Am J Cardiol 1994; 74:1052-6. [PMID: 7977046 DOI: 10.1016/0002-9149(94)90858-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Left ventricular (LV) ejection fraction (EF) is an important measure of systolic function, with radionuclide angiography being the accepted standard for its determination. Echocardiography is ideal for repeated measurements of EF, but most methods are either subject to error in the presence of regional wall abnormalities or require cumbersome off-line analysis. Acoustic quantification is a recently introduced method that allows for the continuous on-line display of LV cavity dimensions, but the on-line algorithm for the measurement of EF has not been validated against an independent standard in the clinical setting. This study attempted to validate acoustic quantification in the determination of EF by comparison with off-line echocardiographic analysis and radionuclide angiography in 54 patients referred for this latter procedure. Acoustic quantification correlated well with off-line analysis in both the apical 4-chamber (r = 0.89, n = 43) and 2-chamber (r = 0.86, n = 26) views. Similarly, it also correlated well with radionuclide angiography in the 4-chamber (r = 0.81, n = 44) and 2-chamber (r = 0.83, n = 26) views. The correlation between the 2 methods was further improved when only the last 30 patients were assessed (r = 0.91, n = 25 for 4-chamber views; r = 0.86, n = 16 for 2-chamber views). The correlation was worse in patients with regional asynergy (r = 0.69, n = 17 for 4-chamber views; r = 0.76, n = 10 for 2-chamber views). Moreover, acoustic quantification tended to underestimate EF when compared with radionuclide angiography.(ABSTRACT TRUNCATED AT 250 WORDS)
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30
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Tardif JC, Cao QL, Pandian NG, Esakof DD, Pollard H. Determination of cardiac output using acoustic quantification in critically ill patients. Am J Cardiol 1994; 74:810-3. [PMID: 7942556 DOI: 10.1016/0002-9149(94)90441-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The reliability of automated acoustic quantification (AQ) in yielding real-time left ventricular (LV) area, volume, and ejection fraction has been validated. The purpose of this study was to explore the potential of AQ in providing accurate immediate determination of cardiac output in critically ill patients. A total of 48 patients were studied. One group consisted of 37 critically ill patients with indwelling Swan-Ganz catheters. In these patients, cardiac output by AQ, manual tracing of end-diastolic and end-systolic frames of 2-dimensional images, and thermodilution were measured. AQ was also compared with Doppler calculation of flow through the left and right ventricles in 11 additional patients. Adequate data for calculation of cardiac output with AQ were obtained in 78% of critically ill patients. There was an excellent correlation between AQ and off-line manual analysis for LV volumes (r = 0.94 and 0.91 for end-diastole and end-systole), ejection fraction (r = 0.85), and cardiac output (r = 0.93). AQ also correlated well with Doppler analysis (r = 0.97) and thermodilution technique (r = 0.95) in the determination of cardiac output. However, AQ slightly underestimated thermodilution measurements, with rather wide limits of agreement (-0.3 +/- 1.1 liter/min). There was a similar underestimation of cardiac output with manual analysis when compared with thermodilution. Given the absence of significant differences between AQ and manual analysis, this observation suggests that the bias is related to the echocardiographic determination of stroke volume, and not to errors from the automated border detection. It is concluded that AQ, besides providing information on LV volumes and ejection fraction, also can yield rapid measurements of cardiac output in most patients who are acutely ill.
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Affiliation(s)
- J C Tardif
- Cardiovascular Imaging and Hemodynamic Laboratory, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02111
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