October 27, 2005Ultrasound in Obstetrics and Gynecology312 citations
View Full PaperDevelopment of Z‐scores for fetal cardiac dimensions from echocardiography
Key Result
Fetal echocardiography in 130 pregnancies allowed the development of regression equations and nomograms to compute Z-scores for 17 fetal cardiac dimensions based on femur length, BPD, or GA.
Study Design
Type
Observational (n=130)
Multicenter
Yes
Structured PICO
P
Population
130 pregnant women with singleton fetuses of gestational age 15-39 weeks undergoing fetal echocardiography.
E
Exposure
Fetal echocardiography to measure 17 cardiac dimensions
O
Outcome
Development of formulae and nomograms allowing computation of Z-scores for fetal cardiac dimensions from knowledge of femur length (FL), biparietal diameter (BPD) or gestational age (GA)surrogate
This study provides formulae and nomograms to calculate Z-scores for 17 fetal cardiac dimensions, enabling quantitative assessment of fetal heart growth in normal and congenitally abnormal hearts.
Abstract
OBJECTIVES: Z-scores for cardiac dimensions are well established in postnatal life, but have yet to be developed for fetal cardiac dimensions. These would be of real advantage to the clinician in accurately quantifying size and growth of cardiac dimensions and to the researcher by allowing mathematical comparison of growth in differing subgroups of a disease. The purpose of this observational study, conducted at tertiary fetal medicine and cardiology units, was to produce formulae and nomograms allowing computation of Z-scores for fetal cardiac dimensions from knowledge of femur length (FL), biparietal diameter (BPD) or gestational age (GA) using fetal echocardiography. METHODS: Seventeen fetal cardiac dimensions were measured in 130 pregnant women with singleton fetuses of gestational age 15-39 weeks. Regression equations were derived relating all dimensions to FL, BPD and GA. From the calculations, formulae were then developed allowing fetal cardiac Z-score computation. RESULTS: The relationships between cardiac dimensions and FL, BPD or GA were described following natural log transformation. From this analysis, FL (taken as an expression of fetal size) had the highest correlation to fetal cardiac dimensions. From the developed nomograms, Z-scores of specific fetal cardiac structures could be estimated from knowledge of the FL, BPD or GA and echocardiographically derived measurements. CONCLUSIONS: This study allowed computation of Z-scores in fetal life for 17 cardiac dimensions from FL, BPD or GA. Previous studies of normal data allowed qualitative assessment of where abnormal cardiac dimensions lay with regard to the normal range. Z-scores from this study allow quantitative analysis of where such dimensions lie relative to the mean. This permits exact assessment of growth of fetal cardiac structures in normal hearts and particularly in congenitally abnormal hearts where quantitative assessment of the growth of cardiac structures is important in analyzing and planning treatment strategies.
Cite This Study
Schneider et al. (Thu,) conducted a observational in Singleton fetuses (n=130). Fetal echocardiography was evaluated on Development of formulae and nomograms for Z-scores of 17 fetal cardiac dimensions. Fetal echocardiography in 130 pregnancies allowed the development of regression equations and nomograms to compute Z-scores for 17 fetal cardiac dimensions based on femur length, BPD, or GA.