Determination of Reference Values for Fetal Cardiac Dimensions in the Third Trimester of Pregnancy

Abstract

INTRODUCTION: The prognosis of congenital heart diseases improves with prenatal detection. Alterations in fetal cardiac dimensions are a common finding in the presence of cardiac abnormalities. OBJECTIVE: To determine reference values for ventricular cavities and diameter of great arteries during the third trimester of pregnancy, in views used in obstetric ultrasound. METHODS: A descriptive cross-sectional study was conducted, determining the distribution of reference values for fetal cardiac dimensions. It took into account sonographic measurements in fetuses between 25 and 41 weeks of pregnant women treated during one year in two private hospitals from Buenos Aires city and one private diagnostic center in Buenos Aires province. RESULTS: Clinical data and fetal cardiac measurements of 577 patients were collected and analyzed. Reference values were determined in terms of mean, standard deviation and percentile curves of ventricular widths, diameters of great arteries, and relationships between these structures (between ventricles and between arteries). CONCLUSIONS: Reference values for fetal heart measurements obtained in sonographic heart views used in obstetric scanning are presented for third trimester fetuses.