Double-outlet right ventricle: an antenatal diagnostic dilemma

Objective The purpose of this study was to describe the antenatal ultrasono graphic findings of fetuses with double-outlet right ventricle (DORV). Design The records were reviewed of all fetuses scanned in our ultrasound u nit which were suspected of having DORV during a 6-year period ending in Ap ril 1996. A medical record search for all infants with a postnatal diagnosi s of DORV was also undertaken to identify cases that were not detected ante natally. Records were examined to determine the accuracy of antenatal diagn osis and the reasons for diagnostic errors. Fetuses without: follow-up were excluded. Results There were 20 fetuses with antenatally detected conotruncal defects that had DORV included in the differential diagnosis. Three fetuses were e xcluded seven did not have DORV and ten were confirmed postnatally as havin g DORV. Two additional infants were found to have DORV from the medical rec ord search, producing a total of 12 cases. Antenatal sonographic cardiac fi ndings included malpositioned (overriding or transposed) great arteries (n = 11), ventricular septal defect (n = 11) and small pulmonary artery sugges ting stenosis (n = 4). Confirmed Post natal cardiac findings that were miss ed antenatally included aortic coarctation (n = 2), right-sided aortic arch (n = 2) and pulmonary stenosis (n = 1). Seven of the 12 fetuses had extrac ardiac findings. Nine of the 12 fetuses tested had a normal karyotype. Elev en of the 12 infants were liveborn. Nine of these 11 survived the neonatal Period and underwent surgical repair within the first year of life; two sub sequently died. In total, seven fetuses survived and five did not. Conclusions Most fetuses with DORV can be identified antenatally as having an abnormal heart. However it is very difficult to distinguish this particu lar defect from other conotruncal abnormalities.