Measurement of the great vessels in the mediastinum could help distinguish true from false-positive coarctation of the aorta in the third trimester.
OBJECTIVE
We investigated the utility of analyzing prenatal mediastinal measures of the great arteries in distinguishing true coarctation of the aorta (CoA) from false-positive CoA.


METHODS
All fetuses in this study had suspicion of CoA based on the presence of right-left heart disproportion. We defined 3 study groups: group 1, true fetal CoA; group 2, false-positive fetal CoA with a narrow aortic arch; and group 3, false-positive fetal CoA without a narrow aortic arch.


RESULTS
In group 1, the mean mediastinal pulmonary artery (PA) to ascending aorta (Ao) diameter ratio +/- SD was 2.03 +/- 0.48, and in group 2, the ratio was 1.60 +/- 0.23. The difference was statistically significant (P = .0018, t test). In group 3, the mean PA:Ao ratio was 1.35 +/- 0.14. The difference between groups 1 and 3 was statistically significant (P = .0002, t test). In our study group, for a PA:Ao ratio of 1.60, sensitivity was 83.0%; specificity, 85.0%; positive predictive value, 62.5%; and negative predictive value, 94.0%.


CONCLUSIONS
In the third trimester, the main PA:Ao ratio as measured in the fetal mediastinum can be a helpful tool in distinguishing true CoA requiring neonatal cardiac surgery from false-positive CoA and simple disproportion requiring medical attention but no surgery in the first month of postnatal life.
Department of Diagnosis and Prevention of Congenital Malformations, Medical University of Lodz, Polish Mother's Memorial Hospital, Lodz, Poland.
Maciej
M
Slodki
Jack
J
Rychik
Tomasz
T
Moszura
Katarzyna
K
Janiak
Maria
M
Respondek-Liberska
D001017:Aortic Coarctation / Q000000981:diagnostic imaging*; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008482:Mediastinum / Q000002:abnormalities* / Q000098:blood supply / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging*; D016216:Ultrasonography, Prenatal / Q000379:methods*