Potential pitfalls and methods of improving in utero diagnosis of transposition of the great arteries, including the baby bird's beak image.
OBJECTIVE
The goal of this study was to analyze our recent experience with fetuses with transposition of the great arteries (TGA) to identify potential pitfalls and possible methods to better detect conotruncal anomalies such as TGA.


METHODS
We analyzed all nonreferral obstetric ultrasound examinations in which we performed basic, targeted, or formal fetal echocardiography with a newborn diagnosis of TGA.


RESULTS
Nine neonates had TGA. Five of these cases were diagnosed prenatally, and 4 of these had complex congenital heart abnormalities. In these 4 cases, there were abnormalities in the cardiac axis (n = 3), abnormal valves or ventricular size (n = 2), and ventricular septal defects (n = 3) that were detected on the 4-chamber view of the heart. In all cases that were not detected prenatally, both prospective and retrospective reviews of the 4-chamber heart appeared normal. The prospective analyses of the outflow tracts were all interpreted as normal, whereas the retrospective review showed subtle abnormalities such as the "baby bird's beak" image. In review of these cases, there was failure to show the "crisscross" relationship of the outflow tracts. In 1 case, 5 short axis views of the heart, retrospectively showed the artery originating from the left ventricle and bifurcated, representing the pulmonary artery.


CONCLUSIONS
Transposition of the great arteries may be associated with complex cardiac disease that could be detected on the 4-chamber view of the heart. When the 4-chamber view is normal, it is important to identify the crisscross relationship of the outflow tracts. If this is not done, it is important to document that the pulmonary artery bifurcates and originates from the right ventricle. Five short axis views of the heart may be helpful to detect conotruncal abnormalities.
McGahan
John P
JP
Department of Radiology, University of California Davis Medical Center, 4860 Y St, Suite 3100, Sacramento, CA 95817, USA. john.mcgahan@ucdmc.ucdavis.edu
Moon-Grady
Anita J
AJ
Pahwa
Anokh
A
Towner
Dena
D
Rhee-Morris
Laila
L
Gerscovich
Eugenio O
EO
Fogata
Maria
M
D004452:Echocardiography / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014188:Transposition of Great Vessels / Q000000981:diagnostic imaging*; D016216:Ultrasonography, Prenatal / Q000379:methods*