Abstract 9578: Normal Ranges of Right Ventricular Strain in Children: A Systematic Review and Meta-Analysis
Background: Establishment of the range of normal values and associated variations of two-dimensional speckle-tracking echocardiography (2DSTE) derived right ventricular (RV) strain is a prerequisite for its routine clinical application in children. The objectives of this study were to perform a meta-analysis of normal ranges of RV longitudinal strain measurements derived by 2DSTE in children and identify confounders that may contribute to differences in reported measures.[[Unable to Display Character:
Methods: A systematic review was launched in PubMed, Embase, Scopus, and Cochrane. Search hedges were created to cover the concepts of pediatrics, speckle-tracking, and right ventricle. Two investigators independently identified and included studies if they reported the 2DSTE derived RV strain measures: RV global longitudinal strain (GS), systolic strain rate (GSRs), early diastolic strain rate (GRSe), late diastolic strain rate (GSRa), or segmental LS at the apical, mid, and basal ventricular levels in healthy children. The weighted mean was estimated by using random-effects with 95% confidence intervals (CI), heterogeneity was assessed by the Cochran’s Q statistic and the inconsistency index (I2), and publication bias was evaluated by funnel plots and the Egger test. Effects of demographic, clinical, and equipment/software variables were assessed in a meta-regression.[[Unable to Display Character:
Results: The search identified 229 children from 10 studies. Normal values varied for GS from -21% to -34% (mean -29%, CI, -32% to -27%), GSRs from -1.3 to -2.4 (mean -1.9, CI, -2.1 to -1.6), GSRe from 1.7 to 2.7 (mean, 2.3, CI, 2.0 to 2.7), and GSRa from 1.0 to 1.3 (mean, 1.2, CI, 1.04 to 1.3). A significant base-to-apex segmental strain gradient (p <0.05) was observed in the RV free wall. There was significant between-study heterogeneity and inconsistency (I2>89% and p<0.01 for each strain measure), which was not explained by age, gender, body surface area, heart rate, frame rate or equipment/software. The meta-regression showed that these effects were not significant determinants of variations among normal ranges of strain values. There was no evidence of publication bias (Egger, p=0.6).[[Unable to Display Character:
Conclusions: This study is the first to define normal values of RV strain in children on the basis of a meta-analysis.
- © 2013 by American Heart Association, Inc.