Imaging Findings
AV canal defect on 4-chamber view of heart. Fetal karyotyping was performed
by cordocentesis for Trisomy 21, and was negative. Though stomach bubble
was not seen on the first scan (Fig 2), it was detected on a subsequent
re-scan. Patient after counseling decided to terminate the pregnancy. Autopsy
confirmed all the findings. Additional truncus arteriosus was found on autopsy.
Situs inversus totalis was found on autopsy (suspected on antenatal scan,
in view of the fact that in a cephalic presentation, apex was pointing away
from transducer).
Final Diagnosis
Atrioventricular septal defect.
Discussion
A common atrioventricular valve is found when there is a defect in both
the atrial and ventricular septa at the crux of the heart, at the normal
point of insertion of the two atrio-ventricular valves. The appearance
is of a single valve opening astride the crest of the ventricular septum.
This is one of the commonest forms of heart disease seen in prenatal
life, accounting for about 17% of cardiac anomalies, and is found usually
in 2 situations: associated with complex cardiac anomalies or associated
with Trisomy 21. When a diagnosis is made, fetal karyotyping should be
performed; prognosis depends on presence of associated cardiac or extra-cardiac
anomalies.
References
Ultrasound
in Obstetrics and Gynaecology. David Cosgrove, 1994. PG 370
Dr.
L Raghunath, Hemavathi Hospital, Hassan, Karnataka
Dr Ramamurthy, Srinivasa Scan Center, Bangalore
|