Down syndrome with tandem 21;21 rearrangement and Ebstein's anomaly--a case report.

Ebstein's anomaly is a rare congenital heart defect (CHD) that occurs approximately once in 20,000 live births and is characterized by significant apical displacement of septal tricuspid leaflet. An increased risk of CHDs, about 40-50%, has been reported among children with Down syndrome. However, an association of Down syndrome with Ebstein's malformation is extremely unusual. Only four cases, to the best of our knowledge, have been previously reported. Tandem translocation 21;21 is rare in Down syndrome in comparison to Robertsonian translocations. A Down infant having a tandem 21;21 translocation trisomy 21 with Ebstein's anomaly is described in this report.