Assessment of left ventricular volumes and function by real time three-dimensional echocardiography in a pediatric population: a TomTec versus QLAB comparison

Three-dimensional speckle tracking echocardiography for evaluation of ventricular function in patients with systemic lupus erythematosus: relationship between duration of lupus erythematosus and left ventricular dysfunction by using global longitudinal strain

BACKGROUND

Cardiovascular diseases are leading causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Cardiac involvement in SLE can often go undetected. Three-dimensional (3D) speckle tracking echocardiography (STE) is a noninvasive imaging technique that can assess the function of the heart's ventricles in an accurate and reproducible way. This makes it an attractive option for detecting early signs of heart disease in SLE patients. By identifying these subclinical cardiac abnormalities, 3D-STE may help reduce the negative impact of cardiovascular diseases in SLE population. Therefore, this study aimed to compare the left ventricular (LV) function between patients with SLE compared to age- and gender-matched controls using two-dimensional (2D) and 3D-STE.

RESULTS

The current study found no significant differences in left ventricle ejection fraction, left ventricle end-diastolic volume, left ventricle end-systolic volume, left ventricle end-diastolic mass, and left ventricle end-systolic mass between the two groups. However, the SLE group exhibited a significantly lower LV global longitudinal strain (GLS) compared to the control group according to all types of echocardiographic assessments, including 3D and 2D long-axis strain, apical 2-chamber, and apical 4-chamber assessments (all P values < 0.05). Furthermore, a good inter-rater reliability and intra-rater reliability were observed regarding the LVGLS measurement with 3D-STE. Additionally, the study identified a significant correlation between LVGLS and SLE duration (r (50) = 0.46, P < 0.001). The use of prednisolone and nephrology disorders was also found to impact LVGLS measurements.

CONCLUSIONS

Despite a normal LVEF in patients with SLE, LVGLS measurements indicated that LV systolic dysfunction was observed more frequently in SLE patients compared to their healthy counterparts. Therefore, advanced 3D-STE techniques may be useful in identifying subtle abnormalities in LV function in SLE patients.

A multicenter study of three-dimensional echocardiographic evaluation of normal pediatric left ventricular volumes and function

BACKGROUND

Three-dimensional echocardiography (3DE) evaluation of left ventricular (LV) volume and function in pediatrics compares favorably with cardiac magnetic resonance imaging. The aim of this study was to establish from a multicenter, normal pediatric z-score values of 3DE left ventricular volumes and function.

METHODS

Six hundred and ninety-eight healthy children (ages 0-18 years) were recruited from five centers. LV 3DE was acquired from the 4-chamber view. A vendor-independent software analyzed end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) using semi-automated quantification. Body surface area (BSA)-based z-scores were generated. Intraobserver and interobserver variability were calculated using intraclass correlation (ICC) and repeatability coefficient (RC).

RESULTS

Z-scores were generated for ESV, EDV, and SV. The ICC for intraobserver variability for EDV, ESV, and SV was 0.99, 0.99, and 0.99, respectively. The ICC for interobserver variability for EDV, ESV, and SV was 0.98, 0.94, and 0.98, respectively. The RC for intraobserver and interobserver variability for LV EF was 4.39% (95% CI: 3.01, 5.59) and interobserver was 7.08% (95%CI: 5.51, 8.42).

CONCLUSIONS

We report pediatric z-scores for normal LV volumes using the semi-automated method from five centers, enhancing its generalizability. 3DE evaluation of LV volumes and EF in pediatric patients is highly reproducible.

Usefulness of three-dimensional echocardiography for assessment of left and right ventricular volumes in children, verified by cardiac magnetic resonance. Can we overcome the discrepancy?

INTRODUCTION

The role of three-dimensional echocardiography (3D-ECHO) chamber quantification in children is still underestimated.

MATERIAL AND METHODS

In 43 children 3D-ECHO measurements of end-diastolic (EDV) and end-systolic ventricular volumes (ESV) were compared to cardiac magnetic resonance (CMR) using Bland-Altman analysis and linear regression. The values of left and right ventricular volumes calculated in 3D-ECHO were compared with each other and verified by CMR.

RESULTS

The values of LV-EDV and LV-ESV measured in 3D-ECHO showed highly significant correlations with CMR (for LV-EDV r = 0.892, p < 0.00001; for LV-ESV r = 0.896, p < 0.00001). In the case of the right ventricle the correlation of 3D-ECHO results with CMR was still high (RV-EDV r = 0.848, p < 0.00001, RV-ESV r = 0.914, p < 0.00001), although mean RV-EDV and RV-ESV in 3D-ECHO were underestimated compared to CMR (by 38% for RV-EDV and 45% for RV-ESV). Correction of 3D-ECHO results using the coefficient of 1.38 and 1.45 for RV-EDV and RV-ESV, respectively, significantly improved the consistency of the results with CMR. 3D-ECHO offered lower mean values of right ventricular volumes compared to the left ventricle. The discrepancy was again reduced by the calculated coefficients.

CONCLUSIONS

3D-ECHO is a valuable tool for assessment of left ventricular volume, which strongly correlates and agrees with CMR. The right ventricular volumes calculated in 3D-ECHO tend to be significantly underestimated in comparison to CMR and corresponding left ventricular volumes obtained from 3D-ECHO. The use of coefficients developed by the study improves the consistency of right ventricular volumes measured by 3D-ECHO with results obtained by CMR and reduces the volumetric discrepancy between ventricles in 3D-ECHO.

Left ventricular mass estimation by real-time 3D echocardiography favourably competes with CMR in congenital left ventricular disease

Assessment of left ventricular mass (LVM) is important in the evaluation of patients with congenital heart disease (CHD) and cardiac magnetic resonance imaging (CMR) is the gold standard. Recent software allows LVM calculation by real-time 3-dimensional echocardiography (RT3DE). We investigated the impact of different software analysis tools on LVM determination by CMR or RT3DE in a cohort of patients with heterogeneous left ventricular (LV) disease. 37 subjects (17 patients, mean age 18.7 y; 20 controls, mean age 13.2 y) underwent CMR and RT3DE. CMR LVM and RT3DE calculations were done using two different LV-analysis software packages for each modality: CMR i) customized software “CMR HDZ”, CMR ii) “CMR ISP”; RT3DE i) “Toshiba”, RT3DE ii) “Tomtec”, 4D LV-Analysis Version 3.1 (built 3.1.0.258661). Intra- and interobserver variabilities were calculated. Only RT3DE-derived LVM showed significant software-dependent differences. RT3DE-derived LVM (both softwares) was significantly higher than CMR-derived LVM (both softwares). The two different methods and four evaluation software packages for LVM assessment were well correlated with each other. Intra- and interobserver variability of LVM as assessed by each single modality or software was low. Despite software dependency and overestimation of RT3DE-assessed LVM by 5 to 10%, RT3DE still competes with the gold standard, CMR, even in patients with various forms of LV disease. The use of optimized software, especially for RT3DE, should improve the accuracy of LVM assessment, overcoming LVM overestimation.

Normal Values and Growth-Related Changes of Left Ventricular Volumes, Stress, and Strain in Healthy Children Measured by 3-Dimensional Echocardiography

Normal pediatric values of three-dimensional (3D) left ventricular (LV) volumes and strain are not well established; moreover, no reports exist of the stress-strain relation and the heart rate-corrected velocity of circumferential fiber shortening (VCFc) based upon 3D imaging in children. Three-dimensional LV datasets were obtained in pediatric patients (≤18 years of age) with structurally normal hearts. Ventricular volumes and strain components (longitudinal, GLS; circumferential, GCS; and 3D strain, 3DS) were analyzed using a commercial 3D speckle-tracking analysis package. LV mid-wall global average end-systolic fiber stress was calculated from 3D LV volumes. A total of 238 patients were included in the analysis with a median age of 13.1 years (range 0.4 to 17.9 years). Regression equations were derived for 3D volume parameters, permitting body surface area-based Z score calculation. Overall, 3DS values were more negative than GLS and GCS (mean ± SD = -33.8 ± 2.8; -27.8 ± 2.9; and -21.7 ± 3.1, respectively); only GLS varied significantly with age (r = 0.22; p <0.001). Both global average end-systolic fiber stress and 3D VCFc increased significantly with age (p <0.001 for both). Stress-adjusted 3DS and VCFc both varied with age (p <0.001 for both), consistent with increased contractility. In conclusion, 3D echocardiography may be used to calculate LV stress, strain, and volumes in pediatric patients with strong reproducibility. Among strain parameters, significant age-related changes were seen only in GLS. Both indexes of contractility investigated (3DS and VCFc indexed to wall stress) improved with age. Future studies of the 3D echocardiography stress-strain relation may yield new insights into maturational changes in myocardial contractility.

Evaluation of longitudinal and radial left ventricular functions on 2-D and 3-D echocardiography before and after intravenous immunoglobulin in acute Kawasaki disease

BACKGROUND

The relationship between left ventricular (LV) function and longitudinal or radial contraction has not yet been elucidated in acute Kawasaki disease (KD), especially before and after treatment with intravenous immunoglobulin (IVIG).

METHODS

We studied 28 KD patients without coronary aneurysms (average age, 3.2 years). The LV end-diastolic volume (LVEDV), end-systolic volume (LVESV), stroke volume (LVSV), and ejection fraction (LVEF) were assessed on 3-D echocardiography before IVIG, after IVIG, and in the convalescent phase. LV fractional shortening (LVFS) and the mitral annular plane systolic excursion (MAPSE) z-score were measured as surrogates for radial and longitudinal LV wall motions, respectively. Serum brain natriuretic peptide (BNP) was also assessed as a heart failure indicator in acute KD patients.

RESULTS

In all KD patients, LVEDV decreased in the acute phase with preservation of LVESV. Both LVSV and MAPSE z-score were lowest before IVIG and increased after IVIG. MAPSE z-score was highly correlated with LVEF before and after IVIG treatment. Although there was a good correlation between logBNP and LVEF before IVIG, it was lost after IVIG.

CONCLUSIONS

LVEDV decreased longitudinally during the acute phase of KD with preservation of LVESV, reducing both LVSV and LVEF. Serum BNP is a useful marker for evaluating LV function only prior to IVIG treatment.

Left ventricular remodeling during and after 60 days of sedentary head-down bed rest

Short periods of weightlessness are associated with reduced stroke volume and left ventricular (LV) mass that appear rapidly and are thought to be largely dependent on plasma volume. The magnitude of these cardiac adaptations are even greater after prolonged periods of simulated weightlessness, but the time course during and the recovery from bed rest has not been previously described. We collected serial measures of plasma volume (PV, carbon monoxide rebreathing) and LV structure and function [tissue Doppler imaging, three-dimensional (3-D) and 2-D echocardiography] before, during, and up to 2 wk after 60 days of 6° head down tilt bed rest (HDTBR) in seven healthy subjects (four men, three women). By 60 days of HDTBR, PV was markedly reduced (2.7 ± 0.3 vs. 2.3 ± 0.3 liters,P< 0.001). Resting measures of LV volume and mass were ∼15% (P< 0.001) and ∼14% lower (P< 0.001), respectively, compared with pre-HDTBR values. After 3 days of reambulation, both PV and LV volumes were not different than pre-HDTBR values. However, LV mass did not recover with normalization of PV and remained 12 ± 4% lower than pre-bed rest values (P< 0.001). As previously reported, decreased PV and LV volume precede and likely contribute to cardiac atrophy during prolonged LV unloading. Although PV and LV volume recover rapidly after HDTBR, there is no concomitant normalization of LV mass. These results demonstrate that reduced LV mass in response to prolonged simulated weightlessness is not a simple effect of tissue dehydration, but rather true LV muscle atrophy that persists well into recovery.

Quantification of left ventricular volumes and function in anesthetized beagles using real-time three-dimensional echocardiography: 4D-TomTec™ analysis versus 4D-AutLVQ™ analysis in comparison with cardiac magnetic resonance imaging

Backround

Real-time three-dimensional echocardiography (RT3DE) enables accurate volume determination of the left ventricle (LV), since measurements in foreshortened depicted views are avertable. Different analyzing programs are available for this RT3DE. The commonly used semi-automatic software 4D-AutLVQ™ showed underestimation of LV volumes in comparison with CMRI in healthy anesthetized dogs (Am J Vet Res 74(9):1223–1230, 2013). TomTec 4D LV-Function™ is an offline analysis program for morphological and functional analyses of the left ventricle by using manual measurement optimization, showing excellent agreement with CMRI in human medicine (Echocardiography 27(10):1263–1273, 2010; Eur J Echocardiogr 11(4):359–368, 2010; Echocardiography 24(9):967–974, 2007). The aim of the present study was to compare these different RT3DE analyzing software programs to test the possibility of one performing better than the other by assessing accuracy and reproducibility in comparison with the reference method cardiac magnetic resonance imaging (CMRI) by determining the left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF).

RT3DE and CMRI were performed during anesthesia in 10 healthy beagles. The analyzing programs 4D-AutLVQ™ (based on semi-automated border detection) and TomTec 4D LV-Function™ (primary manual tracking with semi-automated border detection) were used for RT3DE volume analysis of the left ventricle. Left ventricular EDV, ESV, SV and EF were measured and compared to those measured by the reference method CMRI. Repeated measurements were performed to determine inter- and intra-observer variability.

Results

Both, 4D-AutLVQ™ and 4D-TomTec™ showed small but significant underestimation for EDV and ESV with quite good correlation (r = 0.34–0.69) in comparison with CMRI, without significant difference between each of them. Ejection fraction (EF) measured by 4D-TomTec™ showed no significant differences compared to CMRI (p = 0.12), while 4D-AutLVQ™ significantly underestimated LV-EF (p = 0.03). Analyzing time was shorter using 4D-AutLVQ™ compared to 4D-TomTec™. The inter-observer variability was higher using 4D-TomTec™ than with 4D-AutLVQ™, whereas both methods present excellent intra-observer variability.

Conclusion

4D-TomTec™ and 4D-AutLVQ™ are feasible RT3DE analyzing programs, allowing accurate volume quantification of the left ventricle, albeit with significant underestimation of ventricular volumes in comparison with the gold standard CMRI. 4D-AutLVQ™ is performed faster with less inter-observer variability than 4D-TomTec™. Therefore, 4D-AutLVQ™ is the more practicable measurement method when comparing the different analyzing programs.

Reference Values for Real Time Three-Dimensional Echocardiography-Derived Left Ventricular Volumes and Ejection Fraction: Review and Meta-Analysis of Currently Available Studies

INTRODUCTION

Current guidelines recommend three-dimensional echocardiography (3DE) as the reference technique to assess left ventricular (LV) volumes and ejection fraction (EF). We performed a meta-analysis to identify normative reference values by real time 3DE in healthy subjects.

METHODS

We searched MEDLINE and the Cochrane Library databases using the key search terms three-dimensional echocardiography, volumes, and healthy. Data were pooled using random-effects meta-analysis, and source of variation was investigated using meta-regression. After selection, 13 articles were included (2806 subjects). Four studies were conducted in children and young adolescents; one study provided data in an independent pediatric subgroup.

RESULTS

In adults, pooled mean value for LV EDV was 98.4 mL (95%CI, 87-110 mL), while LV ESV mean value was 37.0 mL (95%CI, 32-42 mL). LV EF mean value was 62.9% (95%CI 61.7-64.2%). Male subjects showed a significant increase in both LV EDV index (mean difference 5.3 mL/m(2) ; P < 0.001) and LV ESV index (mean difference 3.3 mL/m(2) ; P < 0.001). LV EF was significantly higher in female subjects (P = 0.003). In pediatric studies, LV EDV pooled mean value was 53.1 mL (95%CI, 38.1-68 mL), while for LV ESV, it was 19.8 mL (95%CI, 14.8-24.8 mL); LV EF mean value was 63.3% (95%CI, 61.6-65%). Significant heterogeneity and inconsistency were noted among studies. Age, systolic blood pressure, and heart rate were identified as a source of between-studies variation for LV volumes. Body surface area was a predictor of nonindexed LV volumes.

CONCLUSIONS

Data from available studies of normative values for 3DE were summarized. Our findings may increase the generalizability of LV normative data by 3DE.

Fully automatic detection of salient features in 3-d transesophageal images

Most automated segmentation approaches to the mitral valve and left ventricle in 3-D echocardiography require a manual initialization. In this article, we propose a fully automatic scheme to initialize a multicavity segmentation approach in 3-D transesophageal echocardiography by detecting the left ventricle long axis, the mitral valve and the aortic valve location. Our approach uses a probabilistic and structural tissue classification to find structures such as the mitral and aortic valves; the Hough transform for circles to find the center of the left ventricle; and multidimensional dynamic programming to find the best position for the left ventricle long axis. For accuracy and agreement assessment, the proposed method was evaluated in 19 patients with respect to manual landmarks and as initialization of a multicavity segmentation approach for the left ventricle, the right ventricle, the left atrium, the right atrium and the aorta. The segmentation results revealed no statistically significant differences between manual and automated initialization in a paired t-test (p > 0.05). Additionally, small biases between manual and automated initialization were detected in the Bland-Altman analysis (bias, variance) for the left ventricle (-0.04, 0.10); right ventricle (-0.07, 0.18); left atrium (-0.01, 0.03); right atrium (-0.04, 0.13); and aorta (-0.05, 0.14). These results indicate that the proposed approach provides robust and accurate detection to initialize a multicavity segmentation approach without any user interaction.

Comparison of changes in cerebral and systemic perfusion between appropriate- and small-for-gestational-age infants during the first three days after birth

PURPOSE

The aims of the current study were to compare changes in cerebral and systemic perfusion in appropriate-for-gestational-age (AGA) and small-for-gestational-age (SGA) infants immediately after birth.

METHODS

Cerebral blood volume (CBV), cerebral Hb oxygen saturation (cSO2) and cerebral fractional tissue oxygen extraction (cFTOE) among 57 AGA infants and 30 SGA infants were monitored using a newly developed time-resolved spectroscopy system during the first 3days of life. The left ventricular ejection fraction (LVEF), left ventricular cardiac output (LVCO) and E/e' values were determined by three-dimensional echocardiography and tissue Doppler imaging performed simultaneously.

RESULTS

There were significant differences between the body weights of both the AGA and SGA infants, but not between the gestational age and head circumferences in both groups. Although CBV showed no significant difference between the groups, cSO2 was significantly higher and cFTOE was lower in SGA infants than in AGA infants. Hematocrit (Ht) levels were significantly higher and LVEF and LVCO were lower in SGA infants than in AGA infants. Negative correlation was observed between CBV and Ht levels in AGA infants, but not in SGA infants.

CONCLUSIONS

The high Ht levels and vasoreactivity in SGA infants might be a compensatory mechanism in order to maintain oxygen delivery to the brain, which reflects the condition of chronic hypoxia during the fetal period and also reflects the weak contraction and low cardiac output of the left ventricle sustaining the relatively large brain from the fetal period to after birth.

Advanced echocardiographic imaging of the congenitally malformed heart

There have been significant advancements in the ability of echocardiography to provide both morphological and functional information in children with congenitally malformed hearts. This progress has come through the development of improved technology such as matrix array probes and software which allows for the off line analysis of images to a high standard. This article focuses on these developments and discusses some newer concepts in advanced echocardiography such is multi-planar reformatting [MPR] and tissue motion annular displacement [TMAD].

Our aim is to discuss important aspects related to the quality and reproducibility of data, to review the most recent published data regarding advanced echocardiography in the malformed heart and to guide the reader to appropriate text for overcoming the technical challenges of using these methods. Many of the technical aspects of image acquisition and post processing have been discussed in recent reviews by the authors and we would urge readers to study these texts to gain a greater understanding [1]. The quality of the two dimensional image is paramount in both strain analysis and three dimensional echocardiography. An awareness of how to improve image quality is vital to acquiring accurate and usable data.

Three dimensional echocardiography (3DE) is an attempt to visualise the dynamic morphology of the heart. Although published media is the basis for theoretical knowledge of how to practically acquire images, electronic media [eg.www.3dechocardiography.com] is the only way of visualising the advantages of this technology in real time.

It is important to be aware of the limitations of this technology and that much of the data gleaned from using these methods is at a research stage and not yet in regular clinical practice.

Inter-vendor variability of left ventricular volumes and strains determined by three-dimensional speckle tracking echocardiography

BACKGROUND

Inter-vendor discordance in three-dimensional speckle-tracking echocardiography (3DS) remains uncharacterized. We aimed to examine inter-vendor discordance of left ventricular (LV) volumes, and functional parameters and their reproducibilities between two commercially available 3DS systems.

METHODS

Echocardiographic examinations with 3DS were performed in 26 healthy subjects (age 34 ± 13 years, 85% men) using a Vivid E9 system (V1) with 4V probe (GE Health Care) and Artida (V2) with PST-25SX probe (Toshiba Medical Systems) on the same day. LV variables and global LV longitudinal, circumferential, radial, and area strains were measured by vendor-specific softwares, 4D strain EchoPAC BT11 (for V1) and 3D WMT (for V2), respectively. Reproducibility of data was assessed by an intra-class correlation coefficient (ICC).

RESULTS

The mean time required for 3DS analysis was 5.4 ± 1.5 min for V1, being 21% less than that for V2 (6.8 ± 1.9 min, P < 0.01). Reproducibilities of all LV strains were comparable between V1 (ICC 0.50-0.82) and V2 (ICC 0.51-0.76), except for intra-observer and inter-observer reproducibilities of radial strain being lower in V2 (ICC for V1 0.82 and 0.82 and ICC for V2 0.44 and 0.40, respectively). LV strains in all directions and area were significantly different between V1 and V2, though LV volumes and ejection fraction were comparable.

CONCLUSIONS

Global longitudinal, circumferential, and area LV strains are reproducible in both 3DS vendors. However, values of three-dimensional LV strains by 3DS are highly vendor-dependent.

Platelet-rich plasma for the treatment of lateral epicondylitis: sonographic assessment of tendon morphology and vascularity (pilot study)

OBJECTIVE

To investigate the efficacy of using contrast-enhanced ultrasound to assess the relationship of altered vascularity and tendon morphology following injection of platelet-rich plasma (PRP) for lateral epicondylitis.

MATERIALS AND METHODS

This study prospectively evaluated six patients who had a baseline ultrasound confirming tendinosis of the common extensor tendon. Patients received a single 3-ml PRP injection under ultrasound guidance. Grayscale images of the injected elbow were obtained at baseline and were repeated at 1 and 6 months after injection. DEFINITY® contrast was also injected after by 2 sets of wrist-extension exercises in order to obtain contrast-enhanced images of the elbow. Qualitative and quantitative analyses of the level of enhancement to the regions of interest were performed using off-line quantitative analysis software.

RESULTS

All patients had either moderate or severe common extensor tendinosis as determined on clinical examination and baseline imaging. Five patients demonstrated improved tendon morphology using ultrasound imaging 6 months after PRP injection (one patient was lost to follow-up). At baseline, there was evidence of increased vascularity at the myotendinous junction (MT) of the common extensor tendon when compared to its footprint (FP). There was a trend towards no change in FP vascularity between baseline and 6 months (p = 0.062) and between 1 and 6 months (p = 0.288). There was a trend for increased vascularity to the MT region from baseline to 6 months (p = 0.433) and from 1 to 6 months (p = 0.783).

CONCLUSIONS

Contrast-enhanced ultrasound provides a sensitive method the display alterations in vascularity in the common extensor tendon of the elbow. PRP therapy for lateral epicondylitis can improve extensor tendon morphology. Corresponding increased extensor tendon FP vascularity, however, was not seen. There is a trend for increased vascularity at the MT up to 6 months following PRP injection, based on limited pilot data.

[State of the art: new developments in cardiac imaging]

Cardiac imaging continues to reveal new anatomical and functional insights into heart disease. In echocardiography, both transesophageal and transthoracic three-dimensional imaging have been fully developed and optimized, and the value of the techniques that have increased our understanding of cardiac mechanics and ventricular function is well established. At the same time, the healthcare industry has released new devices onto the market which, although they are easier to use, have limitations that restrict their use for routine assessment. Tomography's diagnostic and prognostic value in coronary artery disease continues to increase while radiation exposure becomes progressively lower. With cardiac magnetic resonance imaging, myocardial injury and recovery in ischemic heart disease and following acute coronary syndrome can be monitored in exquisite detail. The emergence of new combined tomographic and gamma camera techniques, exclusively developed for nuclear cardiology, have improved the quality of investigations and reduced radiation exposure. The hybrid or fusion images produced by combining different techniques, such as nuclear cardiology techniques and tomography, promise an exciting future.

Comparison between direct volumetric and speckle tracking methodologies for left ventricular and left atrial chamber quantification by three-dimensional echocardiography

In an era of rapidly expanding and evolving 3-dimensional echocardiographic (3DE) technology, 1 of the issues facing the 3DE quantification of chamber volumes and function is that different software vendors use different methodologies and algorithms. The aim of this study was to evaluate the comparability and reproducibility of 3DE direct volumetric and speckle-tracking methods for left ventricular (LV) and left atrial (LA) chamber quantification. A total of 120 subjects (mean age 53 ± 17 years, 65% men), including 88 unselected patients and 32 healthy volunteers, underwent 3DE acquisitions and analysis using direct volumetric and speckle-tracking methods successively. Measurements of LV and LA volumes and LV function were compared between the 2 3DE methods. Additionally, intraobserver and interobserver reproducibility was assessed in 40 randomly selected patients. Measurements of LV end-diastolic volume, end-systolic volume, and ejection fraction by 3DE direct volumetric and 3DE speckle-tracking methods were comparable, with good correlations (r = 0.98, r = 0.98, and r = 0.87, respectively), small biases, and narrow limits of agreement (-1 ± 8 ml, -1 ± 8 ml, and 0 ± 6%, respectively). For measurements of LA end-systolic volume and end-diastolic volume, similar correlations (r = 0.96 for both), small biases, and narrow limits of agreement (-2 ± 6 and -1 ± 5 ml, respectively) were found between the 2 methods. Intraobserver and interobserver reproducibility for LV and LA quantification were comparable for the 2 methods. In conclusion, 3DE direct volumetric and speckle-tracking methods give comparable and reproducible quantification of LV and LA volumes and function, making interchangeable application a viable option in daily clinical practice.

Ultrasonic image analysis and image-guided interventions

The fields of medical image analysis and computer-aided interventions deal with reducing the large volume of digital images (X-ray, computed tomography, magnetic resonance imaging (MRI), positron emission tomography and ultrasound (US)) to more meaningful clinical information using software algorithms. US is a core imaging modality employed in these areas, both in its own right and used in conjunction with the other imaging modalities. It is receiving increased interest owing to the recent introduction of three-dimensional US, significant improvements in US image quality, and better understanding of how to design algorithms which exploit the unique strengths and properties of this real-time imaging modality. This article reviews the current state of art in US image analysis and its application in image-guided interventions. The article concludes by giving a perspective from clinical cardiology which is one of the most advanced areas of clinical application of US image analysis and describing some probable future trends in this important area of ultrasonic imaging research.