Reference ranges for the size of the fetal cardiac outflow tracts from 13 to 36 weeks gestation: a single-center study of over 7000 cases

Journal article


Vigneswaran, T.V., Akolekar, R., Syngelaki, A., Charakida, M., Allan, L.D., Nicolaides, K.H., Zidere, V. and Simpson, J.M. 2018. Reference ranges for the size of the fetal cardiac outflow tracts from 13 to 36 weeks gestation: a single-center study of over 7000 cases. Circulation Cardiovascular Imaging. 11 (7), p. e007575. https://doi.org/10.1161/CIRCIMAGING.118.007575
AuthorsVigneswaran, T.V., Akolekar, R., Syngelaki, A., Charakida, M., Allan, L.D., Nicolaides, K.H., Zidere, V. and Simpson, J.M.
Abstract

BACKGROUND: Assessment of the outflow tract views is an integral part of routine fetal cardiac scanning. For some congenital heart defects, notably coarctation of the aorta, pulmonary valve stenosis, and aortic valve stenosis, the size of vessels is important both for diagnosis and prognosis. Existing reference ranges of fetal outflow tracts are derived from a small number of cases.

METHODS AND RESULTS: The study population comprised 7945 fetuses at 13 to 36 weeks’ gestation with no detectable abnormalities from pregnancies resulting in normal live births. Prospective measurements were taken of (1) the aortic and pulmonary valves in diastole at the largest diameter with the valve closed, (2) the distal transverse aortic arch on the 3 vessel and trachea view beyond the trachea at the distal point at its widest systolic diameter, and (3) the arterial duct on the 3 vessel and trachea view at its widest systolic diameter. Regression analysis, with polynomial terms to assess for linear and nonlinear contributors, was used to establish the relationship between each measurement and gestational age. The measurement for each cardiac diameter was expressed as a z score (difference between observed and expected value divided by the fitted SD corrected for gestational age) and percentile. Analysis included calculation of gestation-specific SDs. Regression equations are provided for the cardiac outflow tracts and for the distal transverse aortic arch:arterial duct ratio.

CONCLUSIONS: The study established reference ranges for fetal outflow tract measurements at 13 to 36 weeks’ gestation that are useful in clinical practice.

KeywordsValve; Arterial duct; Fetus; Gestational age; Pulmonary valve
Year2018
JournalCirculation Cardiovascular Imaging
Journal citation11 (7), p. e007575
PublisherAmerican Heart Association
ISSN1942-0080
Digital Object Identifier (DOI)https://doi.org/10.1161/CIRCIMAGING.118.007575
Official URLhttp://doi.org/10.1161/CIRCIMAGING.118.007575
Publication dates
Online13 Jul 2018
Publication process dates
Deposited03 Jun 2020
Accepted author manuscript
Output statusPublished
References

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