Real-Time Transthoracic Three Dimensional Echocardiography: Normal Reference Data for Left Ventricular Dyssynchrony in Adolescents

Echocardiographic reference ranges in older children and adolescents in sub-Saharan Africa

BACKGROUND

Echocardiographic reference ranges are important to identify abnormalities of cardiac dimensions. Reference ranges for children in sub-Saharan Africa have not been established. The aim of this study was to establish echocardiographic z-score references for Black children in sub-Saharan Africa.

METHODS

282 healthy subjects aged 6-16years (143 [51%] males) with no known history of cardiac disease were enrolled in the study in Harare, Zimbabwe between 2014 and 2016. Standard M-mode echocardiography was performed and nine cardiac chamber dimensions were obtained. Two non-linear statistical models (gamma weighted model and cubic polynomial model) were tested on the data and the best fitting model was used to calculate z-scores of these cardiac chamber measures. The reference ranges are presented on scatter plots against BSA.

RESULTS

Normative data for the following cardiac measures were obtained and z-scores calculated: right ventricular diameter at end diastole (RVEDD); left ventricular diameter at end diastole (LVEDD) and systole (LVESD); interventricular septal wall thickness at end diastole (IVSd) and systole (IVSs); left ventricular posterior wall thickness at end diastole (LVPWd) and systole (LVPWs); left atrium diameter at end systole (LA) and tricuspid annular plane systolic excursion (TAPSE). Girls had higher values for BMI and heart rate than boys (p=0.048 and p=0.001, respectively). Mean interventricular septal and left ventricular posterior walls thickness was higher than published normal values in predominantly Caucasian populations.

CONCLUSION

These are the first echocardiographic reference ranges for children from sub Saharan Africa and will allow accurate assessment of cardiac dimensions in clinical practice.

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.

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.

Three-dimensional echocardiography and cardiac magnetic resonance imaging in the screening of long-term survivors of childhood cancer after cardiotoxic therapy

The left ventricular (LV) volumes, ejection fraction (EF), and dyssynchrony indexes for the 16 and 12 cardiac segments (Tmsv16-SD and Tmsv12-SD, respectively) were analyzed among nonadult, anthracycline-exposed long-term survivors of childhood cancer and compared with those of healthy controls using conventional and real-time 3-dimensional echocardiography (RT-3DE) with cardiac magnetic resonance (CMR) imaging in a prospective, cross-sectional, single tertiary center setting. Seventy-one survivors and gender-, body surface area-, and age-matched healthy controls were studied by conventional echocardiography and RT-3DE. Fifty-eight of the 71 survivors underwent also CMR. The survivors were evaluated in 2 groups. Group I consisted of 63 exposed to anthracyclines and group II consisted of 8 also exposed to cardiac irradiation. By RT-3DE, the group I survivors had a lower LVEF (57% vs 60%, respectively, p = 0.003) and larger body surface area-indexed LV end-systolic volume (31 vs 28 ml/m(2), respectively, p = 0.001) than controls. The Tmsv16-SD was higher in group II than in I (1.93% vs 1.39%, respectively, p = 0.003). None of the survivors had an abnormal fractional shortening (<28%), but 10% had an LVEF <50% by RT-3DE. An LVEF <55% was detected in 45 of 58 (78%) of those imaged with CMR. In conclusion, RT-3DE seems to detect more abnormalities in cardiac function than conventional echocardiography following childhood cancer therapy. The LV dyssynchrony indexes derived from RT-3DE appear potentially useful in assessing the early signs of cardiotoxicity between anthracycline and cardiac irradiation exposed long-term survivors of childhood cancer.