Racial Variation in Echocardiographic Reference Ranges for Left Chamber Dimensions in Children and Adolescents: A Systematic Review

Abstract

Echocardiography plays a critical role in the assessment of cardiac disease. Important differences in echocardiographically derived cardiac chamber dimensions have been previously highlighted in different population groups in adult studies, but this has not been systematically studied in children, whose body size changes throughout childhood. The aim of this study was to review the distribution of available reference ranges for the left cardiac chamber dimensions in older children and adolescents. The following electronic data bases were searched: Medline, Embase and Web of Science were searched to identify studies which have established echocardiographic reference ranges of left heart parameters in children and adolescents from 1975 to December 2017. There was no geographical limitation. All results were imported into Endnote. Retrieved articles were screened and data extracted by two independent reviewers. A total of 4398 studies were retrieved, with 36 studies finally included in this review. 29 (81%) references were from North America and European (Caucasians) populations, with only one study each from Africa and South America. Two-dimensional and M-mode techniques were the most commonly used echocardiography techniques. There were methodological variations in techniques and normalisation of references. Comparison of selected cardiac measures showed significant differences for interventricular septal thickness among Black African, Indian, German and US American children. Available echocardiographic references cannot be generalised to all settings and therefore, there is need for locally relevant reference ranges. Africa and South America are particularly under-represented. Future studies should focus on developing comprehensive echocardiographic reference ranges for children from different racial backgrounds and should use standardised techniques.Electronic supplementary materialThe online version of this article (10.1007/s00246-018-1873-0) contains supplementary material, which is available to authorized users.

Normal percentile curves for left atrial size in healthy children and adolescents

“…It has been demonstrated that ethnicity and genetic factors contribute to explain the variability in LA dimensions. A recent systematic review based on 36 studies (only one with data from South America) including 30 607 children and adolescents underlined the importance of using race‐specific reference ranges for left cardiac chamber dimensions, as well as the need for standardizing echocardiographic methods in deriving the reference ranges . Then, the value of developing percentile curves for children and adolescents from the Southern Cone of Latin America results easily comprehensible to adequately interpret LA dimensions and early detect LA enlargement.…”

“…Despite the technological advances in cardiovascular imaging, jointly considering accuracy, availability, safety, and versatility, measurement of cardiac structures by 2DE is the preferred modality for the initial evaluation of cardiac structure and function . Moreover, 2DE remains a fundamental tool for evaluation, diagnosis, and decision‐making in children with congenital or acquired heart disease …”

“…In this regard, it is to note that the body changes related with growth and development could include changes in LA structure and function. Hence, the normal and/or reference values for LA dimension could vary according to age, sex, and body surface area (BSA) . However, available data about the relationship between LA size and sex or age are controversial.…”

“…Then, at least in theory, differences in LA could be observed between South American subjects and those from other continents. However, data from South American populations are scarce and unfortunately; in general terms, subjects from South America have been particularly underrepresented when evaluating cardiac (ie, LA) structure and function to define reference values . The above is true not only for adults, but also when considering children and adolescents.…”

“…In this context, our research main purpose was to obtain percentiles for LA diameter (LA D ), volume (LA VOL ) and LA VOL indexed to BSA (LA VOL/BSA ) data obtained from 2DE and M‐mode echocardiography in a cohort of healthy children, adolescents, and young adults nonexposed to cardiovascular risk factors (CRFs) from an Argentinean population …”