In vivo validation of a novel method for regional myocardial wall motion analysis based on echocardiographic tissue tracking.

The objective of this study was to validate a recently developed tissue tracking (TT) method for cardiac motion, by comparing it with precise invasive measurements of motion and to prove its capability to reflect moderate hemodynamic changes induced by asynchronous activation. In four open-chest sheep, sono-crystals measured the left ventricle(LV) equator's diameters simultaneously with 2D ultrasound acquisition. The LV was paced either from the posterior or from the lateral wall, just prior to the normal LV activation. Global functional indices were calculated based on the regional motions extracted by the TT method. The correlation coefficient between the shortening of the diameters and the global circumferential strain (GCS) was 0.99 +/- 0.004. The peak GCS differentiated between the pacing modes (paired t test, P < 0.05). The GCS, a measurement closely based on the TT method, followed the precise sono-crystals measurements and reflected moderate hemodynamic changes, thus providing a substantial proof of the TT method's accuracy and clinical value.

Effect of medical therapy for heart failure on segmental myocardial function in patients with ischemic cardiomyopathy.

The adjustment of medications and dosages to the needs of individual patients with heart failure is mostly intuitive, but even when their effect on global myocardial function is measured by classic indexes, their effect on segmental function is overlooked. This study was conducted to assess the feasibility of using echocardiographic myocardial strain imaging to evaluate the effect of medication on global and segmental function in 21 ambulatory patients with heart failure (mean age 65+/-11 years) who had echocardiographic studies performed before and 2 hours after ingesting their regular morning medications. The ejection fraction, global and regional strain, and time to regional peak strain were compared between the 2 examinations. Medication induced no significant changes in mean ejection fraction (28.6+/-7.8% to 27.5+/-9.9%) and mean global strain (-9.5+/-3.6% to -9.8+/-3.2%). Changes in segmental strain depended on baseline function: normal segments (peak strain more negative than -12%) deteriorated (-15.5+/-2.7% to -13.7+/-4.6%, p<0.0001), but dysfunctional segments (peak strain less negative than -8%) improved (-5.3+/-2.0% to -7.4+/-4.3%, p<0.0001). Medication also improved segmental synchronization: average time to peak strain of segments in which peak strain was attained before aortic valve closure increased (325+/-69 to 375+/-100 ms, p<0.0001), but that of segments with postsystolic shortening at baseline decreased (451+/-93 to 435+/-93 ms, p<0.006). Thus, the time interval between time to peak strain of segments with systolic and post-systolic shortening at baseline was halved after medication. In conclusion, medications for heart failure induced an increase in the echocardiographically determined peak strain of myocardial segments with impaired function at baseline but decreased the peak strain of normally contracting segments. Medications also improved the synchronization of myocardial contraction. Neither the global ejection fraction nor global strain reflected these changes. Thus, medication tended to improve the homogeneity of left ventricular contraction.

Detection of the cardiac activation sequence by novel echocardiographic tissue tracking method.

Asynchronous cardiac activation leads to decreased pumping efficiency. Quantifying the activation sequence may optimize both the selection of patients for cardiac resynchronization therapy (CRT) and its efficacy. The feasibility of assessing the directivity and the degree of synchronous activation with ultrasound was examined. A tissue tracking method (CEB, GE-Ultrasound, AFI, GE Healthcare Inc., Wauwatosa, WI, USA) provided the regional strain profiles. The first maxima in systole of the regional circumferential strains were considered as the activation times. An integrative vector (SDV) describes the activation synchrony and directivity. In six open-chest sheep, activation maps and SDV were calculated in short-axis planes of the left ventricle for normal activation and induced pacings from the anterior and lateral free walls. Both magnitude and angle of the SDV were statistically different (p < 0.05) for the different pacings. Localization of the pacing site was 3 degrees +/- 18 degrees from true position. Conclusions were that motion analysis in echocardiograms provides insightful information regarding the activation process and may enhance procedures such as CRT.

Real-time quantitative automatic assessment of left ventricular ejection fraction and regional wall motion by speckle imaging.

BACKGROUND: Echocardiographic assessment of left ventricular function includes calculation of ejection fraction and regional wall motion analysis. Recently, speckle imaging was introduced for quantification of left ventricular function. OBJECTIVES: To assess LVEF by speckle imaging and compare it with Simpson's method, and to assess the regional LV strain obtained by speckle imaging in relation to conventional echocardiographic scores. METHODS: Thirty consecutive patients, 28 with regional LV dysfunction, underwent standard echocardiographic evaluation. LV end-diastolic volume, LV end-systolic volume and EF were calculated independently by speckle imaging and Simpson's rule. The regional peak systolic strain presented by speckle imaging as a bull's-eye map was compared with the conventional visual estimate of echo score. RESULTS: Average EDV obtained by speckle imaging and by Simpson's method was 85.1 vs. 92.7 ml (P = 0.38), average ESV was 49.4 vs. 48.8 ml (P = 0.94), calculated EF was 43.9 vs. 50.5% (P = 0.08). The correlation rate with Simpson's rule was high: 0.92 for EDV, 0.96 for ESV, and 0.89 for EF. The peak systolic strain in two patients without wall motion abnormality was 17.3 +/- 4.7; in normal segments of patients with regional dysfunction, peak systolic strain (13.4 +/- 4.9) was significantly higher than in hypokinetic segments (10.5 +/- 4.5) (P < 0.000001). The strain in hypokinetic segments was significantly higher than in akinetic segments (6.2 +/- 3.6) (P < 0.000001). CONCLUSIONS: Speckle imaging can be successfully used for the assessment of LV volumes and EF. Bull's-eye strain map, created by speckle imaging, can achieve an accurate real-time segmental wall motion analysis.

Measurement of ventricular torsion by two-dimensional ultrasound speckle tracking imaging.

OBJECTIVES: We sought to examine the accuracy/consistency of a novel ultrasound speckle tracking imaging (STI) method for left ventricular torsion (LVtor) measurement in comparison with tagged magnetic resonance imaging (MRI) (a time-domain method similar to STI) and Doppler tissue imaging (DTI) (a velocity-based approach). BACKGROUND: Left ventricular torsion from helically oriented myofibers is a key parameter of cardiac performance but is difficult to measure. Ultrasound STI is potentially suitable for measurement of angular motion because of its angle-independence. METHODS: We acquired basal and apical short-axis left ventricular (LV) images in 15 patients to estimate LVtor by STI and compare it with tagged MRI and DTI. Left ventricular torsion was defined as the net difference of LV rotation at the basal and apical planes. For the STI analysis, we used high-frame (104 +/- 12 frames/s) second harmonic two-dimensional images. RESULTS: Data on 13 of 15 patients were usable for STI analysis, and LVtor profile estimated by STI strongly correlated with those by tagged MRI (y = 0.95x + 0.19, r = 0.93, p < 0.0001, analyzed by repeated-measures regression models). The STI torsional velocity profile also correlated well with that by the DTI method (y = 0.79x + 2.4, r = 0.76, p < 0.0001, by repeated-measures regression models) with acceptable bias. CONCLUSIONS: The STI estimation of LVtor is concordant with those analyzed by tagged MRI (data derived from tissue displacement) and also showed good agreement with those by DTI (data derived from tissue velocity). Ultrasound STI is a promising new method to assess LV torsional deformation and may make the assessment more available in clinical and research cardiology.

Assessment of myocardial regional strain and strain rate by tissue tracking in B-mode echocardiograms.

To date, established ultrasonic methods for myocardial regional deformation recovery are based on the Doppler effect, which has inherent limitations restricting its accuracy and use. The reported time domain methods show in vivo insufficient accuracy. A novel approach is elaborated mimicking the human observer who reaches robust diagnosis upon the B-mode data. In a region-of-interest (ROI), acoustic markers stable for tracking are selected. A weighting index presenting the quality of tracking of each marker is used for spatial polynomial fitting. For the feasibility study, a simple straight ROI was selected, which matches the septum. A thorough proof of concept is provided by comparing with a gold standard method and by applying the method to clinical datasets. The peak systolic longitudinal strains of 12 normals were -15% + -2.3% and, of 12 patients with a light-to-mild dysfunction of the apical-septal segment, they were -9% + -0.8% (p < 0.05). Enhancements of the method using spline fitting are introduced.

New Automatic Tools to Identify Responders to Cardiac Resynchronization Therapy.

BACKGROUND: New echocardiographic parameters (apical rocking [AR], septal flash [SF]) are intended to detect patterns specific to responders to cardiac resynchronization therapy (CRT). The patterns are visually recognized and qualitatively described, requiring experience and training. Speckle-tracking echocardiography can reflect SF and AR by using newly developed, dedicated parameters, such as start systolic index (SSI) and peak longitudinal displacement (PLD). The aim of this study was to investigate whether SSI and PLD can identify potential CRT responders. METHODS: In 125 patients, echocardiograms from before and 9 ± 3 months after CRT were retrospectively analyzed with dedicated EchoPAC prerelease software. From speckle-tracking baseline images, color-coded bull's-eye displays of SSI and PLD were generated. Cutoff values for both parameters were derived from 25 randomly selected patients and applied to the remaining 100 patients to identify CRT response, defined as a decrease in end-systolic volume of ≥15% during follow-up. The performance of SSI and PLD was compared with the visual assessment of AR and SF by expert and novice readers. RESULTS: Expert readers detected 77 patients with AR, identifying CRT responders with sensitivity and specificity of 85 ± 2% and 82 ± 2%, respectively. Novice readers reached 74 ± 7% sensitivity and 55 ± 11% specificity, while the sensitivity and specificity of the quantitative analysis were 72 ± 3% and 84 ± 4% for SSI and 80 ± 1% and 75 ± 2% for PLD, respectively. CONCLUSIONS: New speckle-tracking-based quantitative assessment of mechanical dyssynchrony by SSI and PLD performs comparably in identifying CRT responders as visual analysis by expert readers and performs significantly better than novice readers.

Two-dimensional speckle tracking echocardiography: standardization efforts based on synthetic ultrasound data.

AIMS: Speckle tracking echocardiography has already demonstrated its clinical potential. However, its use in routine practice is jeopardized by recent reports on high inter-vendor variability of the measurements. As such, the European Association of CardioVascular Imaging (EACVI) and the American Society of Echocardiography (ASE) set up a standardization task force, which was joined by all manufacturers of echocardiographic equipment as well as by companies offering software solutions only, with the ambition to tackle this problem by standardization and quality assurance (QA). METHODS AND RESULTS: In this study, a first step towards QA of all commercially available tracking solutions based on computer-generated ultrasound images is presented. The accuracy of the products was acceptable with relative errors below 10% and intra-vendor reproducibility within 5%. CONCLUSION: Whether these results can be extrapolated to the clinical setting is the topic of an ongoing study of the EACVI/ASE/Industry Task Force to standardize deformation imaging. This study was an important first step in the development of generally accepted tools for QA of speckle tracking echocardiography.

How to define end-diastole and end-systole?: Impact of timing on strain measurements.

OBJECTIVES: This study aimed to investigate to what extent timing definitions influence strain measurements and which surrogates are reliable and feasible to define end-diastole (ED) and end-systole (ES) during speckle-tracking (STI) analysis. BACKGROUND: Current STI-based strain measurements are highly automated. It remains unclear when a particular analysis software defines the zero baseline and the systolic strain measurement position. METHODS: A total of 60 subjects (20 healthy volunteers, 20 patients with coronary artery disease, and 20 patients with typical left bundle-branch block) underwent a complete echocardiographic examination. In one-half of them, a real M-mode through the mitral valve was acquired for each electrocardiographic (ECG) lead of the echo machine. Timing of peak R and automatic ECG trigger were compared with mitral valve closure for every electrode. Mitral and aortic valve closure, as observed in the apical 3-chamber view, served as reference for ED and ES. With the use of these references, end-systolic global longitudinal strain (ES-GLS) and end-systolic segmental longitudinal strain (ES-SLS) longitudinal end-systolic strain were measured at baseline and after changing the definition of either ED or ES by ±4 frames. Furthermore, strain and volume curves derived from the same tracking, as well as the Doppler interrogation of the valves, were compared with the references. RESULTS: Depending on the selected lead, timing of the ECG-derived time markers changed considerably compared with mitral valve closure. Changing the definition of ED and ES resulted in significantly different ES-GLS and ES-SLS values in all subjects. ES-SLS in dyssynchronous hearts showed the highest sensitivity to timing definition. From all methods, spectral Doppler was the most reliable time marker in all subjects (p > 0.05). CONCLUSIONS: Exact temporal definition of ED and ES has a major impact on the accuracy of strain measurements. After direct observation of the valves, Doppler evaluation is the best means for characterizing ED and ES for STI analysis.

Definitions for a common standard for 2D speckle tracking echocardiography: consensus document of the EACVI/ASE/Industry Task Force to standardize deformation imaging.

Recognizing the critical need for standardization in strain imaging, in 2010, the European Association of Echocardiography (now the European Association of Cardiovascular Imaging, EACVI) and the American Society of Echocardiography (ASE) invited technical representatives from all interested vendors to participate in a concerted effort to reduce intervendor variability of strain measurement. As an initial product of the work of the EACVI/ASE/Industry initiative to standardize deformation imaging, we prepared this technical document which is intended to provide definitions, names, abbreviations, formulas, and procedures for calculation of physical quantities derived from speckle tracking echocardiography and thus create a common standard.

Definitions for a common standard for 2D speckle tracking echocardiography: consensus document of the EACVI/ASE/Industry Task Force to standardize deformation imaging.

Recognizing the critical need for standardization in strain imaging, in 2010, the European Association of Echocardiography (now the European Association of Cardiovascular Imaging, EACVI) and the American Society of Echocardiography (ASE) invited technical representatives from all interested vendors to participate in a concerted effort to reduce intervendor variability of strain measurement. As an initial product of the work of the EACVI/ASE/Industry initiative to standardize deformation imaging, we prepared this technical document which is intended to provide definitions, names, abbreviations, formulas, and procedures for calculation of physical quantities derived from speckle tracking echocardiography and thus create a common standard.

Global longitudinal strain: a novel index of left ventricular systolic function.

BACKGROUND: Echocardiographic estimation of global left ventricular (LV) function is subjective and time consuming. Our aim was to develop a novel approach for assessment of global LV function from 2-dimensional echocardiographic images METHODS: Novel computer software for tissue tracking was developed and applied as follows: digital loops were acquired from apical 2-, 3-, and 4-chamber views and a line was loosely traced along the LV endocardium at the frame wherein it was best defined. Around this line, the software selected natural acoustic markers moving with the tissue. Automatic frame-by-frame tracking of these markers during the heart cycle yielded a measure of contractility along the selected region of interest. Global longitudinal strain (GLS) and GLS rate (GLSR) were calculated for the entire U-shaped length of LV myocardium (basal, mid, and apical segments of 2 opposite walls in each view). To test this software, computer-derived GLS and GLSR were analyzed by a nonechocardiographer, blinded to the echocardiographic interpretation, in 27 consecutive patients after myocardial infarction (MI) (age 64.4 +/- 12.9 years; 19 men; mean wall-motion score index of 1.79 +/- 0.44) and compared with those obtained in 12 consecutive control patients (age 59.0 +/- 9.7 years; 8 women), with a normal echocardiographic study. RESULTS: GLS and GLSR, averaged from the 3 apical views, differed significantly in patients post-MI compared with control patients (GLS -14.7 +/- 5.1% vs -24.1 +/- 2.9% and GLSR -0.57 +/- 0.21/s vs -1.02 +/- 0.09/s for patients post-MI vs control patients, respectively; both P <.0001). There was a good linear correlation between the wall-motion score index and the GLS and GLSR (R = 0.68 and R = 0.67, respectively; both P <.0001). A cut-off value for GLS of -21% had 92% sensitivity and 89% specificity and a cut-off value for GLSR -0.9/s had 92% sensitivity and 96% specificity for the detection of patients post-MI. CONCLUSIONS: GLS and GLSR are novel indices for assessment of global LV function from 2-dimensional echocardiographic images. Early validation studies with the method are suggestive of high sensitivity and specificity in the detection of LV systolic dysfunction in patients post-MI.

Two-dimensional strain-a novel software for real-time quantitative echocardiographic assessment of myocardial function.

OBJECTIVES: We sought to assess the feasibility of 2-dimensional strain, a novel software for real-time quantitative echocardiographic assessment of myocardial function. METHODS: Conventional and a novel non-Doppler-based echocardiography technique for advanced wall-motion analysis were performed in 20 patients with myocardial infarction and 10 healthy volunteers from the apical views. Two-dimensional strain is on the basis of the estimation that a discrete set of tissue velocities are present per each of many small elements on the ultrasound image. This software permits real-time assessment of myocardial velocities, strain, and strain rate. These parameters were also compared with Doppler tissue imaging measurements in 10 additional patients. RESULTS: In all, 80.3% of infarct and 97.8% of normal segments could be adequately tracked by the software. Peak systolic strain, strain rate, and peak systolic myocardial velocities, calculated from the software, were significantly higher in the normal than in the infarct segments. In the 10 additional patients, velocities, strain, and strain rate obtained with the novel software were not significantly different from those obtained with Doppler tissue imaging. CONCLUSION: Two-dimensional strain can accomplish real-time wall-motion analysis, and has the potential to become a standard for real-time automatic echocardiographic assessment of cardiac function.

Improving motion estimation by accounting for local image distortion.

Cardiac elastography is a useful diagnostic technique for detection of heart function abnormalities, based on analysis of echocardiograms. The analysis of the regional heart motion allows assessing the extent of myocardial ischemia and infarction. In this paper, a new two-stage algorithm for cardiac motion estimation is proposed, where the data is taken from a sequence of 2D echocardiograms. The method combines the advantages of block-matching and optical flow techniques. The first stage employs a standard block-matching algorithm (sum of absolute differences) to provide a displacement estimate with accuracy of up to one pixel. At the second stage, this estimate is corrected by estimating the parameters of a local image transform within a test window. The parameters of the image transform are estimated in the least-square sense. In order to account for typical heart motions, like contraction/expansion, translation and rotation, a local affine model is assumed within the test window. The accuracy of the new algorithm is evaluated using a sequence of 500 grayscale B-mode images, which are generated as distorted, but known copies of an original ROI, taken from a real echocardiogram. The accuracy of the motion estimation is expressed in terms of errors: maximum absolute error, root-mean-square error, average error and standard deviation. The errors of the proposed algorithm are compared with these of the known block-matching technique with cross-correlation and interpolation in the sub-pixel space. Statistical analysis of the errors shows that the proposed algorithm provides more accurate estimates of the heart motion than the cross-correlation technique with interpolation in the sub-pixel space.

The combined effect of nonlinear filtration and window size on the accuracy of tissue displacement estimation using detected echo signals.

In cardiac elastography, the regional strain and strain rate imaging is based on displacement estimation of tissue sections within the heart muscle carried out with various block-matching techniques (cross-correlation, sum of absolute differences, sum of squared differences, etc.). The accuracy of these techniques depends on a combination of ultrasonic imaging parameters such as ultrasonic frequency of interrogation, signal-to-noise ratio, size of a kernel used in a block-matching algorithm, type of data and speckle decorrelation. In this paper, we discuss the possibility to enhance the accuracy of the displacement estimation via nonlinear filtering of B-mode images before block-matching operation. The combined effect of a filter algorithm and a kernel size on the accuracy of the displacement estimation is analyzed using a 36-frame sequence of grayscale B-mode images of a human heart acquired by an ultrasound system operating at 1.77 MHz. It is shown that the nonlinear filtering of images enables to obtain the desired accuracy (less than one pixel) of the displacement estimation with smaller kernels than without filtering. These results are obtained for two filters--an adaptive anisotropic diffusion filter and a nonlinear Gaussian filter chain.

Use of an automatic application for wall motion classification based on longitudinal strain: is it affected by operator expertise in echocardiography? A multicentre study by the Israeli Echocardiography Research Group.

AIMS: Assessing the quality of wall motion (WM) on echocardiograms remains a challenge. Previously, we validated an automated application used by experienced echocardiographers for WM classification based on longitudinal two-dimensional (2D) strain. The aim of this study was to show that the use of this automatic application was independent of the user's experience. METHODS AND RESULTS: We compared the WM classifications obtained by the application when used by 12 highly experienced readers (Exp-R) vs. 11 inexperienced readers (InExp-R). Both classifications were compared with expert consensus classifications using the standard visual method. Digitized clips of cardiac cycles from three apical views in 105 patients were used for these analyses. Reproducibility of both groups was high (overall intra-class correlation coefficient: InExp-R = 0.89, Exp-R = 0.83); the lowest was noted for hypokinetic segments (InExp-R = 0.79, Exp-R = 0.72). InExp-R scores were concordant with Exp-R mode scores in 88.8% of segments; they were overestimated in 5.8% and underestimated in 3.2%. The sensitivity, specificity, and accuracy of InExp-R vs. Exp-R for classifying segments as normal/abnormal were identical (87, 85, and 86%, respectively). CONCLUSION: Classification of WM from apical views with an automatic application based on longitudinal 2D strain by InExp-R vs. Exp-R was similar to visual classification by Exp-R. This application may be useful for inexperienced echocardiographers/technicians and may serve as an automated 'second opinion' for experienced echocardiographers.

Differential effects of coronary artery stenosis on myocardial function: the value of myocardial strain analysis for the detection of coronary artery disease.

BACKGROUND: Speckle-tracking imaging is a novel method for assessing left ventricular (LV) function and ischemic changes. The aim of this study was to assess the predictive value of two-dimensional longitudinal strain in the detection of longitudinal LV dysfunction and the identification of coronary artery disease (CAD) in patients hospitalized with angina. METHODS: Two-dimensional strain software was extended to allow the analysis of numerous longitudinal strain traces in the entire left ventricle and generate a histogram of peak systolic strain (PSS) values for the left ventricle and for each coronary territory. In each histogram, the value of the 10% worst strain values (PSS(10%)) was determined. Global strain, segmental PSS, and PSS(10%) were analyzed in 97 patients hospitalized with angina and had normal LV function, who underwent coronary angiography, and 51 patients with low probability of CAD. Echocardiography was performed 2.9 ± 2 days after admission. RESULTS: Sixty-nine patients had significant CAD on coronary angiography. Significant differences were observed in all strain parameters between patients with and without CAD. PSS(10%) showed the best accuracy in detecting CAD, with an area under the receiver operating characteristic curve of 0.85. The areas under the curve for global strain and segmental PSS were 0.80 and 0.76, respectively. The optimal cutoff for PSS(10%) was -13.9%, with sensitivity and specificity of 86% and 75%, respectively. PSS(10%) was better than segmental PSS in the detection of CAD in each coronary territory. CONCLUSIONS: In patients hospitalized with angina who have significant CAD on coronary angiography, longitudinal systolic function is impaired. Histogram analysis improved the accuracy of longitudinal strain analysis in detecting global and regional impaired function.

Circumferential and longitudinal strain in 3 myocardial layers in normal subjects and in patients with regional left ventricular dysfunction.

BACKGROUND: The left ventricle is not homogenous and is composed of 3 myocardial layers. Until recently, magnetic resonance imaging has been the only noninvasive technique for detailed evaluation of the left ventricular (LV) wall. The aim of this study was to analyze strain in 3 myocardial layers using speckle-tracking echocardiography. METHODS: Twenty normal subjects and 21 patients with LV dysfunction underwent echocardiography. Short-axis (for circumferential) and apical (for longitudinal strain) views were analyzed using modified speckle-tracking software enabling the analysis of strain in 3 myocardial layers. RESULTS: In normal subjects, longitudinal and circumferential strain was highest in the endocardium and lowest in the epicardium. Longitudinal endocardial and mid layer strain was highest in the apex and lowest in the base. Epicardial longitudinal strain was homogenous over the left ventricle. Circumferential 3-layer strain was highest in the apex and lowest in the base. In patients with LV dysfunction, strain was lower, with late diastolic or double peak. CONCLUSIONS: Three-layer analysis of circumferential and longitudinal strain using speckle-tracking imaging can be performed on a clinical basis and may become an important method for the assessment of real-time, quantitative global and regional LV function.

A new tool for automatic assessment of segmental wall motion based on longitudinal 2D strain: a multicenter study by the Israeli Echocardiography Research Group.

BACKGROUND: Identification and quantification of segmental left ventricular wall motion abnormalities on echocardiograms is of paramount clinical importance but is still performed by a subjective visual method. We constructed an automatic tool for assessment of wall motion based on longitudinal strain. METHODS AND RESULTS: Echocardiograms of 105 patients (3 apical views) were blindly analyzed by 12 experienced readers. Visual segmental scores (VSS) and peak systolic longitudinal strain were assigned to each of 18 segments per patient. Ranges of peak systolic longitudinal strain that best fit VSS (by receiver operating characteristic analysis) were used to generate automatic segmental scores (ASS). Comparisons of ASS and VSS were performed on 1952 analyzable segments. There was agreement of wall motion scores between both methods in 89.6% of normal, 39.5% of hypokinetic, and 69.4% of akinetic segments. Correlation between methods was r=0.63 (P<0.0001). Interobserver and intraobserver reliability using interclass correlation for scoring segmental wall motion into 3 scores by ASS was 0.82 and 0.83 and by VSS 0.70 and 0.69, respectively. Compared with VSS (majority rule), ASS had a sensitivity, specificity, and accuracy of 87%, 85%, and 86%, respectively. ASS and VSS had similar success rates for correct identification of wall motion abnormalities in territories supplied by culprit arteries. VSS had greater specificity and positive predictive values, whereas ASS had higher sensitivity and negative predictive values for identifying the culprit artery. CONCLUSIONS: Automatic quantification of wall motion on echocardiograms by this tool performs as well as visual analysis by experienced echocardiographers, with a greater reliability and similar agreement to angiographic findings.

Reliability of visual assessment of global and segmental left ventricular function: a multicenter study by the Israeli Echocardiography Research Group.

BACKGROUND: The purpose of this multicenter study was to determine the reliability of visual assessments of segmental wall motion (WM) abnormalities and global left ventricular function among highly experienced echocardiographers using contemporary echocardiographic technology in patients with a variety of cardiac conditions. METHODS: The reliability of visual determinations of left ventricular WM and global function was calculated from assessments made by 12 experienced echocardiographers on 105 echocardiograms recorded using contemporary echocardiographic equipment. Ten studies were reread independently to determine intraobserver reliability. RESULTS: Interobserver reliability for visual differentiation between normal, hypokinetic, and akinetic segments had an intraclass correlation coefficient of 0.70. The intraclass correlation coefficient for dichotomizing segments into normal versus other abnormal was 0.63, for hypokinetic versus other scores was 0.26, and for akinetic versus other scores was 0.58. Similar results were found for intraobserver reliability. Interobserver reliability for WM score index was 0.84 and for left ventricular ejection fraction was 0.78. Similar values were obtained for the intraobserver reliability of WM score index and ejection fraction. Compared to angiographic data, the accuracy of segmental WM assessments was 85%, and correct determination of the culprit artery was achieved in 59% of patients with myocardial infarctions. CONCLUSION: Among experienced readers using contemporary echocardiographic equipment, interobserver and intraobserver reliability was reasonable for the visual quantification of normal and akinetic segments but poor for hypokinetic segments. Reliability was good for the visual assessment of global left ventricular function by WM score index and ejection fraction.