Real-Time Three-Dimensional Echocardiographic Acquisition and Quantification of Left Ventricular Indices in Children and Young Adults with Congenital Heart Disease: Comparison with Magnetic Resonance Imaging

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.

ICE-Derived Left Atrial and Left Ventricular Endocardial and Myocardial Speckle Tracking Strain Patterns in Atrial Fibrillation at the Time of Radiofrequency Ablation

Objectives

Intracardiac echocardiography(ICE) has excellent imaging resolution and border recognition which increase strain measurement accuracy. We hypothesized that left atrial(LA) substrate and functional impairment can be detected by measuring LA strain deformation in patients with persistent and paroxysmal atrial fibrillation(AF), as compared to those with no AF. Strain deformation changes in LA and left ventricle(LV) can also be assessed post-ablation to determine its effect.

Methods

ICE-derived speckle tracking strain(STS) was prospectively performed in 96 patients, including 62 patients with AF(31 persistent and 31 paroxysmal AF) pre-/post-ablation, and 34 patients with no AF. We measured major strain parameters including longitudinal segmental(endo/myocardial) "average peak overall strain of all segments"(PkAll), peak strain rate(SR),and different time-to-peak strain in LA and LV images.

Results

At baseline, persistent AF patients had significantly lower(p<0.01) LA endocardial(4.3±2.5 vs. 20.3±8.9 and 25.5±12.9 %) and myocardial PkAll(4.4±2.6 vs. 15.7±7.2 and 20.9±9.2 %), endocardial(0.9±0.4 vs. 1.8±0.7 and 2.2±0.6 1/s) and myocardial peak SR(0.7±0.4 vs. 1.5±0.6 and 1.9±0.5 1/s), as compared to paroxysmal AF and no AF patients. After successful ablation, endo-/myocardial LA PkAll and peak SR were significantly improved, most dramatically in patients with persistent AF. LV endocardial/myocardial strain and SR also improved in AF patients post-ablation.

Conclusion

LA longitudinal strain(%)/SR(1/s) parameters in AF patients are more abnormal than those with no AF, suggesting LA substrate/functional damage. AF ablation improved LA strains/SR but with values in paroxysmal > persistent AF suggesting background LA damage in persistent AF.

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.

Echocardiographic Left Ventricular Mass Estimation: Two-Dimensional Area-Length Method is Superior to M-Mode Linear Method in Swine Models of Cardiac Diseases

Echocardiography offers rapid and cost-effective estimations of left ventricular (LV) mass, but its accuracy in patients with cardiac disease remains unclear. LV mass was measured by M-mode-based linear method and two-dimensional echocardiography (2DE)-based area-length method in pig models and correlation with actual LV weight was assessed. Twenty-six normal, 195 ischemic heart disease (IHD), and 33 non-IHD HF pigs were included. A strong positive linear relationship to the actual LV weight was found with 2DE-based area-length method (r = 0.82, p < 0.001), whereas a moderate relationship was found with M-mode method in the overall population (r = 0.68, p < 0.001). Two correlation coefficients were significantly different (p < 0.001), and were driven mainly by incremental overestimation of LV mass in heavier hearts using the M-mode method. IHD and LV dilation were the factors contributing to overestimation using M-mode method. 2DE-based area-length method provides a better estimation of LV weight in swine models of HF, particularly in those with IHD.

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.

Left ventricular cardiac geometry and ambulatory blood pressure in children

Limited information is available regarding the relationship between ambulatory blood pressure monitoring (ABPM) and cardiac geometry in hypertensive children. ABPM and 2D-echocardiography were retrospectively reviewed in children and adolescents <21 years old with primary hypertension. A total of 119 participants (median age 15.0 [IQR 12, 16] years) with hypertension were included. Left ventricular hypertrophy was diagnosed in 39.5% of participants. Normal geometry was found in 47.1%, concentric remodeling (CR) in 13.4%, concentric hypertrophy (CH) in 15.1%, and eccentric hypertrophy (EH) in 24.4% of children. After adjustment for age, sex, and body mass index z-score, awake systolic blood pressure (BP) index (BPi) (OR 1.07, 95% CI: 1.001-1.14, P = 0.045), awake diastolic BPi (OR 1.04, 95% CI: 1.00-1.09, P = 0.048), awake systolic BP load (OR 1.02, 95% CI: 1.000-1.04, P = 0.047), and sleep systolic BP load (OR 1.02, 95% CI: 1.001-1.04, P = 0.03) were directly associated with CH. No ABPM parameters were significant predictors of EH. In conclusion, ABPM parameters were found to be independent predictors of cardiac geometry, specifically CH.

Quantification of ventricular unloading by 3D echocardiography in single ventricle of left ventricular morphology following superior cavo-pulmonary anastomosis and Fontan completion - a feasibility study

BACKGROUND

Three-dimensional echocardiography. (3DE) is comparable to cardiac magnetic resonance imaging for estimating ventricular volume in congenital heart diseases. However, there are limited data on estimation of ventricular volumes by 3DE in univentricular heart and change in ventricular volumes after surgical creation of cavopulmonary connection. We sought to quantify the unloading of the single ventricle of left ventricular. (LV) morphology by 3DE after superior cavopulmonary anastomosis. (SCPA) or Fontan operation over a period of 3 months and thereby derive a preliminary 3DE data set on this patient subset.

PATIENTS AND METHODS

Eighteen patients with functional single ventricle of LV morphology, who underwent SCPA or completion of Fontan circulation, were included in the study. Volume of the ventricle was estimated by 3DE before surgery and after surgery. (in the early postoperative phase and 3 months after surgery), and indexed end-diastolic volume. (EDV), end-systolic volume. (ESV), and ejection fraction. (EF) were derived.

RESULTS

Twelve patients underwent SCPA and six patients underwent staged completion of Fontan circulation. Before surgery, EDV was similar in both groups. There was a significant fall in EDV immediately after SCPA (from 48.3 ± 14.9 ml/m² to 39.5 ± 12.3 ml/m²). However, EDV increased at 3 months' follow-up to 41.3 ± 10.5 ml/m². There was no significant fall in EDV immediately after Fontan operation (47.2 ± 10.1 ml/m²-46.6 ± 14.2 ml/m²), but EDV continued to fall at 3 months of follow-up (44.7 ± 10. ml/m²). There was no significant change in ESV in either group, but EF fell significantly after SCPA.

CONCLUSIONS

We provide preliminary information on 3DE volume data of single ventricle of LV morphology and the pattern of unloading after SCPA and Fontan operation. Immediate significant volume unloading occurred after SCPA which tended to catch-up after 3 months, whereas continued fall in ventricular volume with time was noted after Fontan.

Usefulness of the maximum rate of pressure rise in the central and peripheral arteries after weaning from cardiopulmonary bypass in pediatric congenital heart surgery: A retrospective analysis

The maximum rate of pressure rise (dP/dtmax) in radial artery has been proposed as a noninvasive surrogate of aortic dp/dtmax, reflecting left ventricular (LV) contractility in children. The aim of this study was to investigate relationship between aortic and radial dp/dtmax at weaning from cardiopulmonary bypass (CPB) and usefulness of these indices for estimating postoperative outcomes in pediatric congenital heart surgery.Aortic and radial arterial pressure waveforms were analyzed simultaneously during weaning from CPB in 29 congenital heart surgery. The maximum first derivatives of aortic and radial arterial waveforms were calculated and averaged from 3 consecutive respiratory cycles. We obtained the maximum vasoactive inotropic score during the first 36 postoperative hours, LV ejection fraction, and fractional shortening on transthoracic echocardiography performed within postoperative day 7.A significant difference between aortic and radial dP/dtmax was observed (mean difference 356 mm Hg/s, 44% of averages), and radial dP/dtmax was weakly correlated with aortic dP/dtmax (r =0.373, P = 0.047). Aortic dP/dtmax was significantly associated with the maximum vasoactive inotropic score (P < 0.001), postoperative LV ejection fraction (P = 0.018), and fractional shortening (P = 0.015); however, radial dP/dtmax was not. On Receiver operating characteristic analysis, aortic dP/dtmax had a greater area under the curve than radial dP/dtmax in predicting higher vasoactive inotropic score (0.827 vs 0.673).Immediately after CPB in pediatric congenital heart surgery, radial dP/dtmax may not replace aortic dP/dtmax because of a discrepancy between central and peripheral arterial waveforms. In this critical period, aortic dP/dtmax can be useful to estimate postoperative ventricular function rather than peripherally derived dP/dtmax.

Three-dimensional Echocardiography in Congenital Heart Disease: An Expert Consensus Document from the European Association of Cardiovascular Imaging and the American Society of Echocardiography

Three-dimensional echocardiography (3DE) has become important in the management of patients with congenital heart disease (CHD), particularly with pre-surgical planning, guidance of catheter intervention, and functional assessment of the heart. 3DE is increasingly used in children because of good acoustic windows and the non-invasive nature of the technique. The aim of this paper is to provide a review of the optimal application of 3DE in CHD including technical considerations, image orientation, application to different lesions, procedural guidance, and functional assessment.

Assessment of Left Ventricular Volume and Function Using Real-Time 3D Echocardiography versus Angiocardiography in Children with Tetralogy of Fallot

BACKGROUND

Evaluation of left ventricular (LV) size and function is one of the important reasons for performing echocardiography. Real time three dimensional echocardiography (RT3DE) is now available for a precise non-invasive ventricular volumetry. Aim of work was to validate RT3DE as a non-invasive cardiac imaging method for measurement of LV volumes using cardiac angiography as the reference technique.

METHODS

Prospective study on 40 consecutive patients with tetralogy of Fallot (TOF) referred for cardiac catheterization for preoperative assessment. Biplane cineangiography, conventional 2 dimensional echocardiography (2DE) and RT3DE were performed for the patients. A control group of 18 age and sex matched children was included and 2DE and RT3DE were performed for them.

RESULTS

The mean LV end diastolic volume (LVEDV) and LVEDV index (LVEDVI) measured by RT3DE of patients were lower than controls (p value = 0.004, 0.01, respectively). There was strong correlation between the mean value of the LVEDV and the LVEDVI measured by RT3DE and angiography (r = 0.97, p < 0.001). The mean value of LV ejection fraction measured by RT3DE was lower than that assessed by 2DE (50 ± 6.2%, 65 ± 4.6%, respectively, p value < 0.001) in the studied TOF cases. There was good intra- and inter-observer reliability for all measurements.

CONCLUSION

RT3DE is a noninvasive and feasible tool for measurement of LV volumes that strongly correlates with LV volumetry done by angiography in very young infants and children, and further studies needed.

Comparison of stroke volumes assessed by three-dimensional echocardiography and transpulmonary thermodilution in a pediatric animal model

To compare stroke volumes (SV) in small hearts assessed by real-time three-dimensional echocardiography (3DE) with SV measured by transpulmonary thermodilution (TPTD) and continuous pulse contour analysis (PC) under various hemodynamic conditions. In thirteen anesthetized piglets (range 3.6-7.1 kg) SV were measured by 3DE, TPTD and PC at baseline and during phenylephrine and esmolol administration. 3DE and TPTD measurements were done successively while SV calculated by PC was documented at the time of 3DE. 3DE and TPTD showed a good correlation (r² = 0.74) and a bias of -1.3 ml (limits of agreement -4.1 to 1.5 ml). While TPTD measured higher SV than 3DE, both methods tracked SV changes with a concordance rate of 91 %. PC and 3DE showed a lower correlation coefficient of r² = 0.57 and a bias of -2.1 ml (limits of agreement -5.9 to 1.8 ml). Inter- and intra-observer variability of SV measured by 3DE was good with a mean bias <5 %. SV_3DE showed a small variance and tracked acute small changes in SV in acceptable concordance with TPTD. PC measured SV with a higher variance and mean difference compared to 3DE. In an experimental setting 3DE has the possibility to offer non-invasive assessments of ventricular volumes volume changes. To determine whether 3DE could be used for SV assessment in a clinical routine our results need confirmation in a clinical setting.

Advanced functional echocardiographic imaging of the failing heart in children

Over the past decade, new echocardiographic techniques such as three-dimensional echocardiography and the imaging of myocardial deformation (strain) have been developed, and are increasingly used in clinical practice. In this article, we describe the rationale and methodology, review available guidelines for practice, and discuss the advantages and limitations of each of these modalities. When available, we have also summarised the scientific evidence for the clinical application of these techniques to detect heart failure in children.

Trends in pediatric imaging: ultrasound

For the last three decades, two-dimensional (2D) echocardiography and Doppler echocardiography have been the primary imaging modalities for the diagnosis and management of heart disease in infants, children, and adolescents. These methods are non-invasive, highly sensitive, and cost-effective, and widely available, making them very useful in clinical work. During this period, the anatomic and hemodynamic abnormalities associated with different congenital and acquired pediatric heart diseases have been well outlined by echocardiography. Recent advances in computer technology, signal processing, and transducer design have allowed the capabilities of pediatric echocardiography to be expanded beyond qualitative 2D imaging and blood flow Doppler analysis. New modalities such as three-dimensional echocardiography, tissue Doppler imaging and speckle tracking echocardiography have been used to evaluate parameters such as ventricular volume, myocardial velocity, regional strain, and strain rate, providing new insight into cardiovascular morphology and ventricular systolic and diastolic function. Accordingly, a comprehensive and sophisticated quantification of ventricular function is now part of most echocardiography protocols. Use of measurements adjusted for body size and age is common practice today. These developments have further strengthened the position of echocardiography in pediatric cardiology.

Comparison of three-dimensional echocardiographic findings to those of magnetic resonance imaging for determination of left ventricular mass in patients with ischemic and non-ischemic cardiomyopathy

The standard echocardiographic evaluation of left ventricular (LV) mass, particularly in ischemic cardiomyopathy (IC) is challenging because it is based on geometric assumptions. The aim of this study was to assess the accuracy of LV mass calculation using echocardiographic modalities compared with cardiac magnetic resonance (CMR) in IC and in nonischemic cardiomyopathy (non-IC). Echocardiography was performed in 104 patients (mean age 55 ± 15 years) referred for CMR: 63 with IC and 41 with non-IC. CMR, M-mode echocardiography, 2-dimensional echocardiography, and 3-dimensional echocardiography (3DE) were analyzed using standard commercial tools to obtain LV mass. LV mass on 3DE showed a higher correlation with CMR than 2-dimensional echocardiography (r = 0.87 vs r = 0.70, p <0.001). M-mode echocardiography overestimated LV mass (bias +30%) and 2-dimensional echocardiography underestimated LV mass (bias -11%), whereas measurements on 3DE showed only minimal bias (-2%). LV mass on 3DE in non-IC showed a significantly higher correlation with CMR than in IC (r = 0.92 vs r = 0.84, z = 2.3, p <0.05). In non-IC, the mean difference was -2 g (-1% of the mean), with 95% limits of agreement of ±33 g (±19% of the mean). In IC, the mean difference was -7 g (-4% of the mean), with limits of agreement of ±56 g (±31% of the mean). There was a correlation between the absolute LV mass differences (3DE derived and CMR derived) and scar percentage (infarcted mass/total LV mass) using delayed-hyperenhancement images (r = 0.40, p <0.05). The net reclassification index with 3DE was +16% for concentric LV hypertrophy. In conclusion, the most accurate and reliable echocardiographic measurement of LV mass is 3DE, but underestimation and variability remain challenges in IC.

Assessment of right ventricular volumes in hypoplastic left heart syndrome by real-time three-dimensional echocardiography: comparison with cardiac magnetic resonance imaging

BACKGROUND

Accurate assessment of right ventricular (RV) volumes and function is important in patients with hypoplastic left heart syndrome (HLHS). We prospectively sought to determine the reproducibility of three-dimensional (3D) echocardiography and its agreement with cardiac magnetic resonance imaging (CMR) in HLHS.

METHODS AND RESULTS

Twenty-eight patients underwent CMR followed immediately by transthoracic 3D echocardiography under general anaesthesia. Semi-automated border detection software was used to determine echocardiographic RV volumes. Inter- and intra-observer variability, correlation and levels of agreement between techniques were determined. The median age was 0.37 years (0.18-9.28 years) and weight 6.24 kg (3.42-32.50 kg). Intra- and inter-observer variability was excellent for both techniques. Median (range) measurements for 3D echocardiography and CMR were; end-diastolic volume (EDV) 23.6 mL (6.5-63.2) and 30.6 mL (11.8-87.9), end-systolic volume (ESV) 12.6 mL (3.7-37.0) and 14.9 mL (5.8-33.9), stroke volume (SV) 11.2 mL (2.8-33.0) and 17.1 mL (6.0-54.1), ejection fraction (EF) 48.2% (31.2-64.9), and 56.5% (42.7-72.2). Correlation coefficients were r = 0.85, 0.84, 0.83, and 0.74, respectively (P < 0.01 for all). Volumetric data were expressed as a percentage of the echocardiographic volume to CMR volume. When compared with CMR, 3D echocardiography underestimated EDV, ESV and SV by 26.7% (SD ± 20.2), 10.6% (±28.1), and 37.5% (±20.1), respectively. The difference in volume appeared largest at low ventricular volumes. EF was 8.3% (±7.3) lower by 3D echocardiography compared with CMR.

CONCLUSION

Both 3D echocardiography and CMR volumes appear highly reproducible. Measurements obtained by 3D echocardiography are significantly lower than those obtained by CMR, with wide limits of agreement such that these two methods cannot be used interchangeably.

5/6 Area length method for left-ventricular ejection-fraction measurement in adults with repaired tetralogy of Fallot: comparison with cardiovascular magnetic resonance

In patients with repaired tetralogy of Fallot (rTOF), left-ventricular ejection fraction (LVEF) predicts adverse outcomes. Two-dimensional echocardiographic (2DE) methods of measuring LVEF require geometric assumptions and may be limited in this population due to altered ventricular geometry. This study evaluated the performance of the 5/6 area × length (AL) method in this population as well as which factors limit agreement with the results of cardiovascular magnetic resonance (CMR). In 20 patients with rTOF (28.5 ± 14.7 years old) and CMR and 2DE within 3 months, two investigators blinded to CMR measured LVEF from 2DE by the AL method, biplane Simpson's (BiS) method, and visual estimate. Two investigators blinded to 2DE measured LVEF from CMR by Simpson's and AL methods. The AL method on 2DE more closely approximated LVEF by CMR (r = 0.73, p = 0.0003) than BiS method (r = 0.53, p = 0.02). AL method was not limited by geometric assumptions, as AL method on CMR closely approximated Simpson's method on CMR (r = 0.90, p < 0.0001) despite median left-ventricular diastolic eccentricity index of 1.24. AL method on 2DE was primarily limited by short-axis area measurement rather than foreshortening of the ventricle. In conclusion, in adults with rTOF, AL method on 2DE moderately approximates LVEF by CMR, even in the context of altered left-ventricular geometry. Although the AL method may be the most appropriate 2DE method in this population, significant limitations remain for LVEF assessment by 2DE, and strategies to optimize image position and border detection are essential.

[Current value of 3D echocardiography in international guidelines]

Real-time 3D echocardiography is one of the most important developments in the field of non-invasive cardiac imaging within the last years. To investigate whether this new technology can be considered as a standard method the current guidelines and recommendations were reviewed. In the field of left ventricular function assessment, evaluation of mitral valve pathologies and peri-interventional monitoring of percutaneous valve repair procedures 3D echocardiography plays a major role. For other clinical applications, such as right heart assessment, congenital heart disease and stress echocardiography, a high potential is seen but evidence is currently too weak for general recommendations. However, in the near future no echo laboratory will be working without 3D modalities.

Meta-analysis of accuracy of left ventricular mass measurement by three-dimensional echocardiography

Left ventricular (LV) hypertrophy is a fundamental prognostic factor in a variety of cardiac diseases. Three-dimensional echocardiography (3DE) has achieved better estimation of LV mass than 2-dimensional echocardiography. However, significant underestimation has often been reported, and no previous study has synthesized these data. The aim of this meta-analysis was to investigate if there has been improvement in the accuracy in LV mass measurement by 3DE over time. Studies comparing LV mass between 3DE and magnetic resonance imaging were eligible. A cumulative meta-analysis was performed to investigate improvement in accuracy, followed by subgroup and meta-regression analysis to reveal factors affecting the bias. A total of 25 studies including 671 comparisons were analyzed. Studies published in or before 2004 showed high heterogeneity (I(2) = 69%) and significant underestimation of LV mass by 3DE (-5.7 g, 95% confidence interval -11.3 to -0.2, p = 0.04). Studies published from 2005 to 2007 were still heterogenous (I(2) = 60%) but showed less systematic bias (-0.5 g, 95% confidence interval -2.5 to 1.5, p = 0.63). In contrast, studies published in or after 2008 were highly homogenous (I(2) = 3%) and showed excellent accuracy (-0.1 g, 95% confidence interval -2.2 to 1.9, p = 0.90). Investigation of factors affecting the bias revealed that evaluation of cardiac patients compared to healthy volunteers led to larger bias (p <0.05). In conclusion, this meta-analysis elucidates the underestimation of LV mass by 3DE, its improvement over the past decade, and factors affecting the bias. These data provide a more detailed basis for improving the accuracy of 3DE, an indispensable step toward further clinical application.

Echocardiography as a hemodynamic monitor in critically ill children

Echocardiography is a widely used modality to assess myocardial structure and function in pediatric intensive care settings. While the use of echocardiography for diagnostic purposes remains important, its use as a hemodynamic monitoring tool has not been well established. The benefits of echocardiography are in its widespread availability, relative ease of use, and importance in diagnosing structural disease and simple changes in myocardial function. However, echocardiography in pediatric critical care is limited in its use because it requires the acquisition of quality images and the accurate interpretation of the study. To date, the literature on echocardiography in pediatric critical care is limited. The purpose of this review is to examine the scientific evidence for the usefulness of echocardiography as a hemodynamic monitoring tool in pediatric critical care.

A meta-analysis and investigation for the source of bias of left ventricular volumes and function by three-dimensional echocardiography in comparison with magnetic resonance imaging

Determining accurate left ventricular (LV) function is clinically important. Three-dimensional echocardiography (3DE) achieves better estimation than 2-dimensional echocardiography. However, underestimation of LV volumes has often been reported without a systematic attempt to synthesize these data. This meta-analysis aimed to assess the bias of 3DE in evaluating LV volumes and ejection fraction (EF) and to investigate factors affecting that bias. Studies that compared LV volumes and/or EF between 3DE and magnetic resonance imaging were eligible. Meta-analysis of 95 studies including 3,055 subjects revealed significant underestimation of LV end-systolic volume (-4.7 ml, p <0.0001) and end-diastolic volume (-9.9 ml, p <0.0001), whereas measurement for EF revealed excellent accuracy (-0.13%, p = 0.41). Meta-regression analysis for factors of systematic bias in volumetry revealed that female gender and existence of cardiac disease were associated with more underestimation, whereas use of semiautomatic tracking and matrix-array transducers counteracted the underestimation. In conclusion, by meta-analysis synthesizing many small studies, we found underestimation of LV volumes and factors affecting the systematic bias by 3DE. These data provide a more detailed basis for analyzing and improving the accuracy of 3DE, an indispensable step toward further clinical application in LV assessment.

Identifying same-cell contours in image stacks: a key step in making 3D reconstructions

Identification of contours belonging to the same cell is a crucial step in the analysis of confocal stacks and other image sets in which cell outlines are visible, and it is central to the making of 3D cell reconstructions. When the cells are close packed, the contour grouping problem is more complex than that found in medical imaging, for example, because there are multiple regions of interest, the regions are not separable from each other by an identifiable background and regions cannot be distinguished by intensity differences. Here, we present an algorithm that uses three primary metrics-overlap of contour areas in adjacent images, co-linearity of the centroids of these areas across three images in a stack, and cell taper-to assign cells to groups. Decreasing thresholds are used to successively assign contours whose membership is less obvious. In a final step, remaining contours are assigned to existing groups by setting all thresholds to zero and groups having strong hour-glass shapes are partitioned. When applied to synthetic data from isotropic model aggregates, a curved model epithelium in which the long axes of the cells lie at all possible angles to the transection plane, and a confocal image stack, algorithm assignments were between 97 and 100% accurate in sets having at least four contours per cell. The algorithm is not particularly sensitive to the thresholds used, and a single set of parameters was used for all of the tests. The algorithm, which could be extended to time-lapse data, solves a key problem in the translation of image data into cell information.

Validation of 3D echocardiographic assessment of left ventricular volumes, mass, and ejection fraction in neonates and infants with congenital heart disease: a comparison study with cardiac MRI

BACKGROUND

quantitative assessment and validation of left ventricular (LV) volumes and mass in neonates and infants with complex congenital heart disease (CHD) is important for clinical management but has not been undertaken. We compared matrix-array 3D echocardiography (3D echo) measurements of volumes, mass, and ejection fraction (EF) with those measured by cardiac MRI in young patients with CHD and small LVs because of either young age or LV hypoplasia.

METHODS AND RESULTS

thirty-five patients aged <4 years (median, 0.8 years) undergoing MRI were prospectively enrolled. Three-dimensional echo was acquired immediately after MRI, and volume, mass, and EF measurements, using summation of discs methodology, were compared with MRI. Three-dimensional echo end-diastolic volume (24.4±15.7 versus 24.8±46.4 mL; P=0.01; intraclass correlation coefficient [ICC], 0.96) and end-systolic volume (12.3±8.6 versus 9.6±6.8 mL; P<0.001; ICC, 0.90) correlated with MRI with small mean differences (-0.49 mL [P=0.6] and 2.7 mL [P=0.001], respectively). Three-dimensional echo EF was smaller than MRI by 9.3% (P<0.001), and 3D echo LV mass measurements were comparable to MRI (17.3±10.3 versus 17.6±12 g; P<0.77; ICC, 0.93), with a small mean difference (1.1 g; P=0.28). There was good intra- and interobserver reliability for all measurements.

CONCLUSIONS

in neonates and infants with CHD and small LVs (age appropriate or hypoplastic), matrix-array 3D echo measurements of mass and volumes compare well with MRI, providing an important modality for ventricular size and performance analysis in these patients, particularly in those with left-side heart obstructive lesions.

Current cardiac imaging techniques for detection of left ventricular mass

Estimation of left ventricular (LV) mass has both prognostic and therapeutic value independent of traditional risk factors. Unfortunately, LV mass evaluation has been underestimated in clinical practice. Assessment of LV mass can be performed by a number of imaging modalities. Despite inherent limitations, conventional echocardiography has fundamentally been established as most widely used diagnostic tool. 3-dimensional echocardiography (3DE) is now feasible, fast and accurate for LV mass evaluation. 3DE is also superior to conventional echocardiography in terms of LV mass assessment, especially in patients with abnormal LV geometry. Cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) are currently performed for LV mass assessment and also do not depend on cardiac geometry and display 3-dimensional data, as well. Therefore, CMR is being increasingly employed and is at the present standard of reference in the clinical setting. Although each method demonstrates advantages over another, there are also disadvantages to receive attention. Diagnostic accuracy of methods will also be increased with the introduction of more advanced systems. It is also likely that in the coming years new and more accurate diagnostic tests will become available. In particular, CMR and CCT have been intersecting hot topic between cardiology and radiology clinics. Thus, good communication and collaboration between two specialties is required for selection of an appropriate test.

Automated border detection in three-dimensional echocardiography: principles and promises

Several automated border detection approaches for three-dimensional echocardiography have been developed in recent years, allowing quantification of a range of clinically important parameters. In this review, the background and principles of these approaches and the different classes of methods are described from a practical perspective, as well as the research trends to achieve a robust method.

The gold standard for noninvasive imaging in congenital heart disease: echocardiography

PURPOSE OF REVIEW

Echocardiography in pediatric and congenital heart disease is a key diagnostic technique in patients with congenital heart disease. Due to new technological developments, it has become a rapidly evolving field.

RECENT FINDINGS

In this review, we focus on recent developments in standardization and validation of standard techniques in pediatric and congenital echocardiography. This is mainly related to standardization of image acquisition and normalization of measurements for body size. The rest of the review is focused on the application of three-dimensional echocardiography, tissue Doppler imaging and Speqle tracking techniques to pediatric heart disease.

SUMMARY

New developments in standardization of echocardiography, the introduction of three-dimensional echocardiography and new functional techniques such as tissue Doppler and Speqle tracking strengthen the position of pediatric echocardiography as the most important diagnostic tool for patients with congenital heart disease.

[Update on pediatric cardiology and congenital heart disease]

The fields of pediatric cardiology and congenital heart disease have experienced considerable progress in the last few years, with advances in new diagnostic and therapeutic techniques that can be applied at all stages of life from the fetus to the adult. This article reviews scientific publications in a number of areas that appeared between August 2007 and September 2008. In developed countries, congenital heart disease is becoming increasingly prevalent in nonpediatric patients, including pregnant women. Actions aimed at preventing coronary heart disease must be started early in infancy and should involve the promotion of a healthy diet and lifestyle. Recent developments in echocardiography include the introduction of three-dimensional echocardiography and of new techniques such as two-dimensional speckle tracking imaging, which can be used for both anatomical and functional investigations in patients with complex heart disease, including a univentricular heart. Progress has also occurred in fetal cardiology, with new data on prognosis and prognostic factors and developments in intrauterine interventions, though indications for these interventions have still to be established. Heart transplantation has become a routine procedure, supplemented in some cases by circulatory support devices. In catheter interventions, new devices have become available for the closure of atrial or ventricular septal defects and patent ductus arteriosus as well as for percutaneous pulmonary valve implantation. Surgery is also advancing, in some cases with hybrid techniques, particularly for the treatment of hypoplastic left heart syndrome. The article ends with a review of publications on cardiomyopathy, myocarditis and the treatment of bacterial endocarditis.

[Update on cardiac imaging techniques: echocardiography, cardiac magnetic resonance, and multidetector computed tomography]

This article contains a review of the most important publications on cardiac imaging that have appeared during 2008. During the year, we assisted with the clinical implementation of three-dimensional real-time transesophageal echocardiography, with the use of echocardiography for selecting patients for and monitoring those who underwent percutaneous aortic valve replacement (the majority of centers performing the technique were still in the learning phase), and with the emergence in the clinic of techniques for studying myocardial deformation. Also reviewed are the most significant developments in the application of echocardiography to coronary heart disease and cardiac resynchronization therapy and in 2 other techniques whose use is constantly increasing: cardiac magnetic resonance and multidetector cardiac computed tomography. The review ends with a description of the current state of the art in contrast echocardiography, with particular emphasis on safety in the context of recommendations made by the US Food and Drug Administration at the end of 2007.