QLAB Version Research Articles

Efficacy of Artificial Intelligence Software in the Automated Analysis of Left Ventricular Function in Echocardiography in Central Vietnam.

In recent years, there has been a significant focus on the development of artificial intelligence (AI) applications in healthcare. However, current scientific evidence is still not convincing enough for the general public and the medical community to widely adopt AI in clinical practice. We conducted this study to investigate the correlation between left ventricular function indices assessed by AI and those evaluated by physicians. This cross-sectional descriptive study was conducted on 136 patients who attended and received treatment at Hue University of Medicine and Pharmacy Hospital from April 2022 to June 2023. Using QLAB version 15, Philips Healthcare. The AI software accurately identified 98.5% of the echocardiographic cine-loops. However, there were about 1.5% of cine-loops that the software failed to recognize. The sensitivity of Ejection Fraction (EF) calculated by AI was 73.3%, specificity was 81.3%, and accuracy stood at 78.6%. A strong positive correlation was observed between EF measured by AI and that assessed by physicians, r = 0.701, p < 0.01. The sensitivity of Global Longitudinal Strain (GLS) calculated by AI was 42.1%, specificity was 84.8%, and accuracy was 67.6%. A moderate positive correlation was found between GLS measured by AI and physician's assessment, r = 0.460, p < 0.01. The use of AI software for evaluating left ventricular function through ejection fraction and global longitudinal strain is rapid and yields results comparable to cardiologists' echocardiographic assessments. The AI-powered software holds a promising and feasible future in clinical practice.

Two-dimensional echocardiographic and strain values of the proximal thoracic aorta in a normal sub-Saharan African population

BackgroundThere is limited data regarding reference ranges for aortic dimensions in African populations. This study aims to establish normal reference ranges for echocardiographic dimensions and circumferential strain (CS) of the proximal thoracic aorta in a healthy sub-Saharan African population.MethodsThis was a secondary analysis of data from a prospective cross-sectional study of 88 participants conducted at Chris Hani Baragwanath Hospital (2017–2019). Aortic measurements were obtained as per the 2015 American Society of Echocardiography guidelines using a Philips iE33 system. Circumferential Strain was measured using Philips QLAB version 11.0 software offline semi-automated analysis of speckle-based strain 2-D speckle-tracking software (Amsterdam, The Netherlands).ResultsMean age was 37.22 ± 10.79 years (41% male). The mean diameter at the aortic annulus, sinuses, sino-tubular junction (STJ) and ascending aorta (AAO) were 19.11 ± 2.38 mm, 27.40 ± 6.11 mm, 25.32 ± 3.52 mm and 25.36 ± 3.38 mm, respectively. Males had larger absolute and indexed aortic diameters at all levels when compared to females. The mean aorta CS was 11.97 ± 5.05%. There was no significant difference in CS based on gender (12.19 ± 5.04% vs 11.51 ± 5.02%, P = 0.267). On multivariate linear regression analysis, male sex was the most significant predictor of increased diameter at the level of the aortic annulus (r = 0.17, P = 0.014), body surface area was the most significant predictor at the sinuses (r = 0.17, P = 0.014) and AAO (r = 0.30, P < 0.001), while age was the most significant predictor at the STJ (r = 0.27, P = 0.004). There was a negative correlation between age and aortic CS (r = − 0.12, P < 0.001). The most important predictor of aorta CS was age, on multivariate analysis (r = − 0.19, P = 0.024).ConclusionsThis study provides normal reference ranges for dimensions of the proximal aorta and circumferential strain (CS) in a sub-Saharan African population according to age, sex, and body habitus. It serves as a platform for future larger studies and allows for risk stratification of cardiovascular disease in an African population.

Effects of Preload Manipulation on Right Ventricular Contractility: Invasive Pressure-Area Loop versus Non-invasive Strain-Area Loop

Effects of Preload Manipulation on Right Ventricular Contractility: Invasive Pressure-Area Loop versus Non-invasive Strain-Area Loop

Advantage and validation of vendor-independent software for myocardial strain analysis compared to vendor-specific software.

One of the main limitations incorporating strain imaging into widespread clinical practice is inter-vendor incompatibility. This poses a problem when serial strain measurements are required in a multi-vendor echocardiography laboratory. This study sought to compare the variability of two-dimensional speckle-tracking global and regional longitudinal strain using vendor-specific software and vendor-independent software from images acquired by two different commercially available ultrasound systems. Forty subjects underwent two sequential echocardiographic acquisitions using different ultrasound systems (GE Vivid E9 and Philips iE33). Global longitudinal strain and regional peak longitudinal strain were derived using vendor-specific software (EchoPAC BT 13 v201 and QLAB version 10.3) and vendor-independent software (TomTec Image Arena version 4.6). Agreement and reproducibility of global and regional strain between vendor-specific and vendor-independent software were assessed by independent blinded observers. Global longitudinal strain derived from vendor-independent software was comparable to global longitudinal strain derived from vendor-specific software, whilst regional strain was lower in agreement compared to global longitudinal strain. There was good overall agreement and high inter- and intra-observer reproducibility using vendor-independent software for global longitudinal strain and regional strain. Vendor-independent software provides good agreement with vendor-specific software for global longitudinal strain. However, minor variability exists for regional strain measurements between vendor-independent and vendor-specific software. Good agreement of strain measurements derived by vendor-independent software suggests vendor-independent software could potentially be useful for serial follow-up of global longitudinal strain.

VP34.13: Fetal 2D speckle‐tracking echocardiography: a comparison of two different software tools

The aim of the study was to compare Philips and TomTec 2D speckle-tracking echocardiography (2D-STE) software measurements of strain and dyssynchrony values in healthy fetuses. This was an explorative observational study in which the echocardiographic data of 93 healthy fetuses between the 20th and 38th week of gestation were determined from a four-chamber view using 2D speckle tracking. The global and segmental longitudinal strain values of both ventricles, interventricular and left intraventricular dyssynchrony were analysed using QLab version 10.8 (Philips Medical Systems, Andover, MA, USA) and TomTec-Arena version 2.30 (TomTec, Unterschleißheim, Germany). TomTec showed persistenly lower values for all of the assessed strain and dyssynchrony variables. For all variables, the bias between vendors tended to increase with gestational age, though not to a significant extent. Left ventricular dyssynchrony and longitudinal strain within the mid segment of the septum correlated best between vendors; however, the limits of agreement were wide in both cases. None of the variables assessed in the two-chamber view compared well between QLab and TomTec. Speckle-tracking software cannot be used interchangeably between vendors. Further investigations are necessary to standardize fetal 2D-STE.

Speckle tracking echocardiographically-based analysis of ventricular strain in children: an intervendor comparison

BackgroundStrain and synchrony can be calculated from a variety of software packages, but there is a paucity of data with inter-vendor comparisons in children. To test the hypothesis that different packages may affect results, independent of acquisition, we compared values obtained using two commercially available analysis tool (QLAB and TomTec), with several different settings.MethodsThe study population included 108 children; patients were divided into three groups: (1) normal cardiac structure and conduction; (2) ventricular paced rhythm; and (3) flattened ventricular septum (reflecting right ventricular pressure or volume load lesions). We analyzed the same image acquired from the apical 4-chamber (AP4) and short-axis at the mid-papillary level (SAXM) views in both QLAB (versions 10.5 and 10.8) and TomTec (version 1.2). In QLAB version 10.8, low, medium, and high quantification smoothness settings were employed. In TomTec, images were analyzed with both low and high frame rates. Tracking quality for each package was graded. AP4 and SAXM strain and synchrony values were recorded. A mixed-effects linear regression model was used, with main effect considered significant if the p-value was < 0.05.ResultsTracking scores were high for all packages except QLAB 10.5 in the SAXM view. AP4 and SAXM strain values varied significantly between QLAB 10.5 and the other packages. Synchrony values varied widely for all strain values (p < 0.001 for both) in all packages. Quantification smoothness changes in QLAB 10.8 did not impact strain significantly in any patient group; temporal resolution changes in TomTec resulted in strain differences in children with flat ventricular septums, but not those with normal or ventricular paced hearts.ConclusionSynchrony values varied substantially among all packages in children. Strain values varied widely between QLAB 10.5 and all other software packages, recommending avoidance of QLAB 10.5 for future studies. Quantification smoothness settings in QLAB 10.8 resulted in minimal strain differences. In TomTec, low and high frame rate strain values differed only in a subset of patients (flattened septum). These data suggest that reliable comparisons between strain values derived from QLAB and TomTec is possible in certain cases, but that caution should be used especially in different hemodynamics conditions.

282 Advantage and Validation of Vendor-Independent Software for Global and Regional Strain Analysis

One of the main limitations for incorporating strain imaging into widespread clinical practice is inter-vendor incompatibility. This study sought to compare the variability of two-dimensional speckle-tracking derived global and regional longitudinal strain using vendor-specific software (VSS) and vendor-independent software (VIS) from images acquired by two different commercially available high-end ultrasound systems. 40 subjects underwent two sequential echocardiographic acquisitions using two different ultrasound systems (GE Vivid E9 and Philips iE33). Global longitudinal strain (GLS) and regional peak longitudinal strain were derived using VSS (EchoPAC BT 13 and QLAB version 10.3) and VIS (TomTec Image Arena version 4.6). Agreement (Blan-Altman Bias) and reproducibility of strain values between VSS and VIS were assessed using intraclass correlation coefficient (ICC). GLS values analysed by VIS on images acquired on different ultrasound systems showed no significant difference (TomTec strain analysis on GE images; -18.6±4.8 vs TomTec strain analysis on Philips images; -19.2±4.8, p=0.09). VIS GLS was comparable to VSS GLS, whilst regional strain was lower in agreement compared to GLS. There was good overall agreement using VIS for GLS (Bias: Philips images =-0.02, Bias: GE images =-0.91) and high inter- and intra-observer reproducibility (Interobserver ICC =0.92, Intraobserver ICC =0.96). VIS provides good agreement with VSS for GLS. Variability exists for regional strain between VIS and VSS. Good agreement for VIS strain values from images acquired using different ultrasound systems suggest VIS could potentially be useful for serial follow-up of GLS.

P306 Left ventricular volumes during 3D transesophageal echocardiography in comparison to those obtained by 3D transthoracic echocardiogram. A feasibility study

Abstract Background Three dimensional (3D) transthoracic echocardiogram (TTE) has been validated to have good agreement with cardiac magnetic resonance for the assessment of left ventricular ejection fraction (LVEF) with good interobserver reproducibility. Despite the increased use of perioperative transesophageal echocardiogram (TEE), TEE assessment of left ventricular (LV) function and volumes have never been validated against 3D TTE. Objective To evaluate whether 3D TEE measurement of LV function shows better agreement with 3DTTE, compared to 2DBiplane and X-plane TEE. Methods A total of 60 patients were included from a single large volume tertiary center, the mean age of 71.9 years, 40% were female; TTE and TEE studies were performed within one week. LV function parameters including LV EF, LV end-diastolic (LVEDV) and end systolic volumes (LVESV), stroke volumes (SV) were calculated with Qlab version 9, and 3DQ advanced software, with semi-automated endocardial contours for 3D TTE and 3D TEE. LV function parameters for 2D X-plane and Biplane TEE data sets were assessed using AGFA with manual endocardial contours. Mean differences were compared with paired, two-tail T-test, and limits of agreement were determined using the Bland-Altman analysis. Correlation between TTE and TEE values were tested using Pearson’s correlation test. Results 3D transthoracic LV EDV, ESV, SV, and EF respectively were 112± 46 ml, 57 ±32 ml, 55± 55 ml, and 51 ±11%. Comparisons and correlations between TTE and TEE for the four measures were: for EDV bias = 9.94 ml and 95% lower and upper limits of agreements being -68.7 and 88.5 ml, and r= 0.7; for ESV the bias was -0.3 ml with 95% lower and upper limits of agreements being -55 to 55 ml, and r = 0.7: for stroke volume bias= 0.2 with 95% lower and upper limits of agreements being -37 to 67 ml, and r = 0.2; for LVEF the bias was 2.7% with 95% lower and upper limits of agreements being -18.9% to 24.3%, and r= 0.7 (Fig) Conclusion Left ventricular volumetric assessments during 3D transesophageal echocardiography is not only feasible but also comparable to 3D transthoracic echocardiography obtained LV volumes and EF. Data from multicenter studies with a larger number of subjects are needed to corroborate our findings. Abstract P306 Figure. Fig. 3D LV volumes by 3D TEE vs. 3D TTE

P1546 Reproducibility of right atrial myocardial deformation by two-dimensional speckle tracking

Abstract Background Right atrial (RA) deformation by two-dimensional speckle tracking echocardiography has a relatively new technique to evaluate right heart function with pulmonary hypertension and cardiomyopathy. Reproducibility between observers of this technique is important to develop into a robust and reliable tool. Experience may pose significant challenges. Purpose The aim of this study is to evaluate reproducibility of RA strain (global and regional) between novice and expert. Methods One hundred thirty-three patients (n = 133) underwent 2D-Speckle tracking derived RA strain analysis by 3 independent blinded readers (expert and 2 novices). The novice observers were medical interns with no prior experience in performing strain analysis. Echocardiographic images were acquired from iE33 (Philips Medical System) but were analysed offline using single vendor dependent software (QLAB version 11.0; Philips Medical System). The result of novice observer was calculated by the average of novice observers. RA strain parameters were assessed: global RA strain and segmental (Basal, Mid, Roof). Intraobserver and interobserver analyses were performed using intra class correlation coefficients (ICC) between expert and novice. Results Expert and novice observer demonstrated good interobserver reproducibility of global RA strain (ICC 0.88) and segmental parameters (Basal: ICC 0.89, Mid: ICC 0.87, Roof: ICC 0.84). Of all parameters, the basal segment of RA strain showed the greatest interobserver agreement. Intraobserver agreement for novice observer was excellent for global RA strain and segmental parameters (ICC &amp;gt; 0.88). Conclusions Global RA strain and segmental parameters were highly reproducible by novice and expert strain observer.

Studying of morphology and left ventricular function by conventional and speckle tracking echocardiography in football players

Objective: Recent studies have showed that Tissue Doppler Imaging and Speckle Tracking Echocardiography can discover these changes at functional and structural cardiac in athletes at early stage, especially at the footballers. The purpose of this research was evaluated the structural and functional adaption of left ventricular in footballer by conventional and advanced echocardiography. Materials and methods: We performed a cross-sectional study of 30 footballers who have been trained over 2 years compared to 30 healthy candidate with the same ages. We carried out TM, 2D, STE. Echo machine was Philips Affinity 50CV with QLAB version 10.04 which can analyze online or offline. Result: In comparison with control group, IVSd, LVEDd, PWTd, LVM, LVMI (p = 0.001) was different from athlete group. Left ventricular adaption trended to eccentric hypertrophy and increased left ventricular mass index. A wave was decrease velocity and increased E/A, E/El’, E/E’s ratio. Base circumferential strain, apex circumferential strain, rotation and twist (10.12 ± 1.2) (°) athletes (7.42 ± 2.6) (°) control group with (p = 0.05), were more than control group. Conclusion: Conventional and advanced echocardiography can evaluate structural and functional left ventricular adaption in athletes. Especially, STE provided more data in myocardial deformation, rotation and twist so that it can discover these changes at athlete heart in early stages Key words: Athletes heart, Speckle Tracking Echocardiography, Tissue Doppler Imaging

Comparison of Longitudinal and Apical Foetal Speckle Tracking Echocardiography Using Tissue Motion Annular Displacement and Segmental Longitudinal Strain

The aim of our prospective pilot study with exploratory analysis was to compare longitudinal and apical foetal speckle tracking echocardiography (STE) using tissue motion annular displacement (TMAD) and segmental longitudinal strain (SLS). We compared two different STE quantification tools in a longitudinal and apical four-chamber view in 57 normal foetuses between 20 and 40 wk of gestation. Myocardial mechanical dyssynchrony and strain were assessed using offline quantification software (QLab Version 10.3, Philips Medical Systems, Andover, MA, USA). We compared the dyssynchrony measurements with TMAD and SLS in longitudinal and apical four-chamber views. Furthermore, we examined the segmental strain values of both ventricles with SLS and compared the differences between longitudinal and apical measurements. Dyssynchrony measurements with TMAD and SLS and strain measurements with SLS were feasible in all cases. In the apical view, the dyssynchrony measurements with TMAD were systematically greater than those achieved with SLS (p < 0.001). For the longitudinal view, no differences were observed between tools (p = 0.153). The application of SLS provided similar results for dyssynchrony in both views (intra-class correlation coefficient [ICC] = 0.281, p = 0.623), but the strain measurements in the left and right ventricles differed significantly between views (ICC = –0.082, p = 0.011, and ICC = –0.061, p = 0.024, respectively). For TMAD, we found large differences in the dyssynchrony values between longitudinal and apical assessment (ICC = –0.060, p = 0.03). Furthermore, TMAD exhibited reduced accuracy in the system's automatic tracking algorithm, limiting the data quality. The dyssynchrony assessment is affected less by the foetal position in SLS than in TMAD. The strain readings in SLS varied depending on the view in which they were assessed. The application of TMAD cannot be recommended for foetal STE.

Improvement in Strain Concordance between Two Major Vendors after the Strain Standardization Initiative

Disagreement of strain measurements among different vendors has provided an obstacle to the clinical use of strain. A joint standardization task force between professional societies and industry was initiated to reduce intervendor variability of strain. Although feedback from this process has been used in software upgrades, little is known about the effects of efforts to improve conformity. The aim of this study was to assess whether intervendor agreement for global longitudinal strain (GLS) has improved after standardization initiatives. Eighty-two subjects (mean age, 52±21years; 55% men) prospectively underwent two sequential examinations using two most common ultrasound systems (Vivid E9 and iE33). GLS was calculated using proprietary software (EchoPAC-PC BT12 [E12] and BT13 [E13] vs QLAB version 8.0 [Q8], QLAB version 9.0 [Q9], and QLAB version 10.0 [Q10]). Agreements in GLS were evaluated with Bland-Altman plots. Coefficients of variation (CVs) were compared using the Friedman test and compared with CVs of left ventricular volumes and ejection fraction (LVEF). Median GLS using E12 was -19.2% (interquartile range [IQR], -15.2% to -23.2%), compared with -19.3% (IQR, -14.9% to -23.7%) for E13, -15.7% (IQR, -11.4% to -20%) for Q8, -19% (IQR, -15.7% to -22.3%) for Q9, and -18.7% (IQR, -15.7% to -21.7%) for Q10. The CVs of prestandardization GLS (12 ± 8% [E12/Q8] and 14±8 [E13/Q8]) were significantly larger than that of LVEF (5±5) (P<.001). Since standardization, the CVs of GLS have shown improvement (6±4 [E12/Q9], 7±4 [E12/Q10], 6±4 [E13/Q9], and 7±4 [E13/Q10]) and are similar to those of LVEF. Subsequent to the joint standardization task force, there has been improvement in between-vendor concordance in GLS between two leading ultrasound manufactures, the variability of which is now analogous to that of LVEF. The removal of concerns about measurement variability should allow wider use of GLS.

O055 The effect of right ventricular pacing site on left ventricular myocardial deformation

Introduction: Previous studies have suggested that long-term right ventricular apex (RVA) pacing causes dyssynchronous left ventricular (LV) contraction, promoting heart failure and increasing mortality. Placing a lead against the right ventricular high septum (RVHS) allows closer proximity to the His-Purkinje system and therefore may allow more physiological depolarisation of the left ventricle. However, recent clinical studies regarding the influence of pacing sites on LV function have produced conflicting results. Objectives: We hypothesized that RVA pacing would worsen myocardial deformation more than than RVHS pacing. Methods: In this multicenter, randomized controlled trial of 240 pts (74 11yrs, 67% males) with preserved LVEF and implanted pacemaker due to high grade atrioventricular block, deformation imaging was possible in 148 pts, of whom 78 were randomized to RVA and 70 to RVHS. We measured LVEF and global longitudinal strain (GLS) using speckle tracking (EchoPAC PC BT11: GE Healthcare, QLAB version 9.1: Philips Medical Systems) at baseline (post pacemaker implantation) and at two years. Results: In the RVA group, the mean LVEF at baseline was 56.8 8.5% and at two years was 53.6 9.6 (p1⁄40.002) and in the RVHS baseline LVEF was 55.8 10.1 and at two years 53.2 10.4 (p1⁄40.013). In the RVA group, the mean GLS at baseline was -15.9 4.0% and at two years was -13.9 4.0 (p<0.001) and in the RVHS baseline LVEF was -16.5 4.8 and at two years -15.6 4.6 (p1⁄40.050). There was no significant change in LVEF between RVA and RVHS lead position for two years (5.2 17.9 vs 4.4 23.5 %, p1⁄40.871), but the change in GLS was significantly larger in RVA than that in RVHS (10.7 23.6 vs 3.4 23.2 %, p1⁄40.045) (Figure).

O056 Left ventricular geometry and function assessed by three-dimensional echocardiography immediately refer to volume overload in patients on hemodialysis

Introduction: Previous studies have suggested that long-term right ventricular apex (RVA) pacing causes dyssynchronous left ventricular (LV) contraction, promoting heart failure and increasing mortality. Placing a lead against the right ventricular high septum (RVHS) allows closer proximity to the His-Purkinje system and therefore may allow more physiological depolarisation of the left ventricle. However, recent clinical studies regarding the influence of pacing sites on LV function have produced conflicting results. Objectives: We hypothesized that RVA pacing would worsen myocardial deformation more than than RVHS pacing. Methods: In this multicenter, randomized controlled trial of 240 pts (74 11yrs, 67% males) with preserved LVEF and implanted pacemaker due to high grade atrioventricular block, deformation imaging was possible in 148 pts, of whom 78 were randomized to RVA and 70 to RVHS. We measured LVEF and global longitudinal strain (GLS) using speckle tracking (EchoPAC PC BT11: GE Healthcare, QLAB version 9.1: Philips Medical Systems) at baseline (post pacemaker implantation) and at two years. Results: In the RVA group, the mean LVEF at baseline was 56.8 8.5% and at two years was 53.6 9.6 (p1⁄40.002) and in the RVHS baseline LVEF was 55.8 10.1 and at two years 53.2 10.4 (p1⁄40.013). In the RVA group, the mean GLS at baseline was -15.9 4.0% and at two years was -13.9 4.0 (p<0.001) and in the RVHS baseline LVEF was -16.5 4.8 and at two years -15.6 4.6 (p1⁄40.050). There was no significant change in LVEF between RVA and RVHS lead position for two years (5.2 17.9 vs 4.4 23.5 %, p1⁄40.871), but the change in GLS was significantly larger in RVA than that in RVHS (10.7 23.6 vs 3.4 23.2 %, p1⁄40.045) (Figure).

Quantitative Evaluation of Contrast-Enhanced Ultrasonography in the Diagnosis of Chronic Ischemic Renal Disease in a Dog Model

ObjectivesThe aim of this feasibility study was to prospectively explore in a dog model of chronic ischemic renal disease (CIRD) the hypothesis that real-time contrast-enhanced ultrasonography (CEUS) can quantitatively evaluate the early perfusion changes of renal cortex.Materials and MethodsIn this animal care and use committee-approved study, the model of CIRD was carried out in healthy dogs (10.0∼12.0 kg, n = 5), by placing the Ameroid ring constrictors on the distal portion of right renal artery through operation. CEUS monitoring of right kidney perfusion was performed by intravenous bolus injection of 0.6 ml Sulfur hexafluoride filled microbubbles (SonoVue; Bracco S.P.A., Milan, Italy) every week after operation. The slope rate of ascending curve (A) and descending curve (α), area under curve (AUC), derived peak intensity (DPI), and time to peak (TTP) were measured in renal cortex using commercial quantification software (Q-LAB version 6; Philips Medical Systems, Bothell,WA,USA). The sensitivity of CEUS was compared with blood serum urea nitrogen (BUN) and serum creatinine (SCr) level.ResultsWith the progression of CIRD, dogs showed delayed enhancement and perfusion in renal CEUS curve. Earliest significant changes happened 4 weeks after operation on DPI and TTP which changed from 13.04±2.71 to 15.58±4.75 dB and 9.03±2.01 to 10.62±6.04 sec, respectively (P<.05).ConclusionsCEUS can display the perfusion changes of CIRD in the early period.

Tissue motion annular displacement of the mitral valve using two-dimensional speckle tracking echocardiography predicts the left ventricular ejection fraction in normal children

The gold standard for determining the left ventricular ejection fraction is cardiac magnetic resonance imaging. Other parameters for determining the ejection fraction such as M-mode echocardiography are operator-dependant and often inaccurate. Assessment of the displacement of the mitral valve annulus using two-dimensional speckle tracking echocardiography may provide an accurate and simple method of determining the left ventricular ejection fraction in children. We retrospectively studied 70 healthy 9-year-old children with no history of cardiovascular disease who had been assessed using cardiac magnetic resonance imaging and two-dimensional transthoracic echocardiography. Mitral displacement was determined using the tissue motion annular displacement (TMAD) feature of Philips QLAB version 9. The midpoint displacement of the mitral valve was calculated, and the predicted left ventricular ejection fraction was compared with magnetic resonance imaging-derived and M-mode-derived ejection fractions. The mean ejection fraction derived from magnetic resonance imaging (64.5 (4.6)) was similar to that derived from the TMAD midpoint (60.9 (2.7), p = 0.001) and the M-mode (61.9 (7), p = 0.012). The TMAD midpoint correlated strongly with the magnetic resonance imaging-derived ejection fraction (r = 0.69, p < 0.001), as did the predicted fraction (r = 0.67, p < 0.001). The M-mode ejection fraction showed a poor linear correlation with both magnetic resonance imaging-derived and TMAD-derived fractions (r = 0.33 and 0.04, respectively). TMAD of the mitral valve is a simple, effective, and highly reproducible method of assessing the ejection fraction in normal children. It shows a strong linear correlation with magnetic resonance imaging-derived ejection fraction and is superior to M-mode-derived ejection fractions.

Abstract 9346: Left Ventricular Dyssynchrony Estimated by Real time 3D Echocardiography Acutely Onset after ST-Elevation Myocardial Infarction Predicts Left Ventricular Remodeling

Background: Left ventricular dyssynchrony, estimated by speckle-tracking radial strain immediately after AMI, has been recognized as a predictor of LV remodeling. Methods: The study included 119 consecutive patients (99men, 64years, maxCPK=3138±3642IU/l) presenting with a first ST-elevation AMI (STEMI) who underwent primary PCI within 12 hours of onset. Within 24 h of intervention, 2D echocardiography, including tissue Doppler, speckle-tracking strains, and 3D echocardiography, was performed by iE33 and Q-lab version 8.1 (CMQ and 3DQ ADV, Philips inc). Echocardiography was repeated 12 months later and LV remodeling was defined as an absolute increase in LVEDV of at least 20%. The absolute difference (Tmsv-16dif) and standard deviation (SD) of the time to regional LV minimum systolic volume (Tmsv-16SD) for all 16 segments were assessed by 3D echocardiography. The absolute differences in time-to-peak radial (Tm-rad), circumferential (Tm-cir), and longitudinal (Tm-lon) strains were assessed for the earliest versus the latest activated segments. Longitudinal images were obtained by their apical 4-, 2-, long axis view and longitudianal strain was calculated from these images. Results: In total, 37 patients had LV remodeling at the 12-month follow-up. Each dyssynchronous index was a significant predictor for LV remodeling. Table shows univariate and multivariate analysis for predicting LV remodeling. Multivariable analysis demonstrated that Tmsv-16SD was the independent predictor among these indexes (Odds ratio=1.183, CI : 1.039-1.441, p=0.0046). We corrected Tmsv-16SD by the R-R interval to give Tmsv-16SD%. The Tmsv-16SD% value strongly predicted LV remodeling (Odds ratio = 1.609, CI : 1.336-2.029, p&lt;0.0001). Conclusions: In patients with a first STEMI, LV dyssynchrony assessed by 3D echocardiography immediately after reperfusion therapy can predict LV remodeling within 12 months.

Abstract 9116: In Patients with Preserved Ejection Fraction, Newer Measures of Systolic Function Have Better Correlation with Functional Status Than Do Traditional Measures of Diastolic Function

Introduction: Multiple abnormalities in left ventricular (LV) systolic and diastolic function have been demonstrated in patients with heart failure and preserved ejection fraction. We aimed to determine which echocardiographic measures of LV systolic or diastolic function best correlate with functional status in patients with preserved ejection fraction (EF). Methods: Patients referred for clinically indicated echos who had images adequate for evaluation of regional myocardial function were approached for enrollment. Functional status was determined by the Duke Activity Status Index (DASI), which correlates with peak oxygen uptake. Echos were analyzed by investigators blinded to DASI scores. EF was determined with Simpson's biplane method. Speckle tracking echo (STE) (QLab version 7.1 Philips, The Netherlands) was used to determine peak circumferential, radial, and longitudinal strain for each LV segment. Torsion was defined as the maximal difference between apical and basal twist. Standard Doppler techniques were used to measure peak early (E) and atrial (A) filling velocities as well as peak early velocity (E') of the medial mitral annulus. Results: 34 patients with an EF ≥ 45% were enrolled. There was no correlation between E/E' and DASI scores (r=0.008, p=0.97, n=24). Whereas, there was a relatively strong correlation between DASI scores and radial strain (r=0.703, p=0.003, n=15). There were moderate correlations between DASI scores and global longitudinal strain (r=-0.54, p=0.038, n=15), global circumferential strain (r=-0.392, p=0.087, n=20) and torsion (r=0.462, p=0.054, n=18). Using a backwards fit technique, a model including global radial strain and torsion provides the best prediction of DASI scores, [DASI score = -9.039 + (2.141×torion) + (1.083× radial strain)], (r= 0.731, p=0.003 n=14). Conclusions: In our cohort of patients with preserved EF, traditional measures of diastolic function (E/E') had no correlation with functional status. Systolic measures, such as radial strain, correlated the best with functional status. STE derived measures of LV systolic events may be a more appropriate variable than traditional diastolic measures in studies investigating patients with preserved EF.

Pattern and Impact of Altered Regional Myocardial Excursion on Global Ventricular Performance After First-Time Acute Anterior Wall Myocardial Infarction by Real-Time Three-Dimensional Echocardiography

The regional wall motion score index obtained by two-dimensional echocardiography in myocardial infarction (MI) has a significant impact on left ventricular (LV) global contractility and is of extraordinary prognostic value, whereas data regarding real-time three-dimensional echocardiography (RT-3DE) are lacking. We sought to clarify the relationship between RT-3DE and LV contractility in patients after MI. RT-3DE was performed in 50 patients with anterior wall acute myocardial infarction and 30 normal controls. Global (16 segments) and regional ring-based LV systolic excursions were analyzed offline using the commercially available software Q-Lab version 5.0. The correlations between the LV global and regional systolic excursions and the global LV contractile performance were examined in the MI patients, and further compared with the control group. The global and regional (basal and middle ring-based) LV systolic excursions were lower in the MI patients (age, 61.8 ± 13.1 years) than in the normal controls (age, 40.0 ± 15.4 years). Global excursion showed inverse linear relationships with LV end-systolic volume ( r =-0.26, p < 0.05) and end-diastolic volume ( r =-0.22, p < 0.05) but no significant relationships with LV ejection fraction ( p = 0.08) and stroke volume ( p = 0.49). Regional wall motion abnormalities quantified by RT-3DE are clinically convenient and feasible in both MI patients and the normal population. This rapid and objective quantification may also help discriminate abnormal from normal regional and global functions after infarction and, therefore, has the potential to be an attractive solution for clinical diagnosis.

Accuracy and Reproducibility of Quantitation of Left Ventricular Function by Real-Time Three-Dimensional Echocardiography Versus Cardiac Magnetic Resonance

The aim of this study was to investigate the accuracy and reproducibility of the quantification of left ventricular (LV) function by real-time 3-dimensional echocardiography (RT3DE) using current state-of-the-art hardware and software. Compared with cardiac magnetic resonance (CMR), previous generations of hardware and software for RT3DE significantly underestimated LV volumes partly because of inherent factors such as limited spatial and temporal resolution. Also, RT3DE volumes were compared with short-axis CMR data, whereas a combined short-axis and long-axis analysis is known to be superior. Twenty-four subjects (mean age 51 +/- 12 years, 17 men) in sinus rhythm and with good to excellent 2-dimensional image quality underwent RT3DE and CMR within 1 day. The acquisition of RT3DE data was done with current state-of-the-art hardware and software. Two blinded experts performed off-line LV volume analysis. Global LV volumes were determined from semiautomated border detection on the basis of endocardial speckle tracking with biplane projections using QLAB version 6.0. Volumes derived by magnetic resonance imaging were quantified from combined short-axis and long-axis series. The volume-rate on RT3DE was 33 +/- 8 Hz (range 19 to 42). Excellent correlations were found (R2 > or = 0.97) between CMR and RT3DE for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes (24 phases/cardiac cycle). Bland-Altman analyses showed mean differences of -7.1 ml, -4.2 ml, 0.2%, and -5.8 ml and 95% limits of agreement of +/-19.7 ml, +/-8.3 ml, +/-6.2%, and +/-15.4 ml for global LV end-diastolic volume, LV end-systolic volume, the LV ejection fraction, and LV phase volumes, respectively. Interobserver variability was 5.2% for global LV end-diastolic volume, 6.4% for LV end-systolic volume, and 7.6% for the LV ejection fraction. In conclusion, in patients with good acoustic windows, RT3DE using state-of-the-art technology provides accurate and reproducible measurements of global LV volumes, LV volume changes over time, and the LV ejection fraction.