We report the rare two cases of interrupted aortic arch (IAA) with right descending aorta
(RDA). Case 1, 23-days old boy presented with cyanotic episode. His face was like a conotruncal anomaly face and he had chromosome 22 q 11.2 (D 22 S 75) deletion. The echocardiogram showed IAA, a large perimenbranous venticular septal defect (VSD) with posterior malaligment, RDA continuous with a right ductus arteriosus (PDA). CT scan showed that the right PDA was over the right main bronchus.He was diagnosed IAA type B with right aortic arch and at the age of 2 months, he underwent surgical repair under cardiopulmonary bypass consisting of right arch repair, patch closure of VSD and ligated PDA. He was discharged postoperatively and is doing well. Case 2, 1-month old girl presented with heart murmur.She did not have chromosome 22 q 11.2 (D 22 S 75) deletion. The echocardiogram showed IAA, superoinferior ventricles , double outlet right ventricle, remote type VSD and bicuspid aortic valve.Angiocardiography showed taht the left brachiocephalic artery and right common carotid artery arose from ascending aorta, and right subclavian artery arose from the RDA.PDA arose from left pulmonary artery continuous to the RDA, and was over the left main bronchus. She was diagnosed IAA type A of left aortic arch with aberrant origin of right subclavian artery and at the age of 2 months, she underwent surgical repair under cardiopulmonary bypass consisting of left arch repair, patch closure of VSD and ligated PDA. She is doing well.