Summary:A double aortic arch is usually an isolated abnormality. We describe a case with a previously undescribed combination of tetralogy of Fallot with pulnion a y atresia, complete atrioventricular septal defect, and left patent arterial duct in association with a double aortic arch. A complete diagnosis was made by echocardiography . Meticulous suprasternal echocardiography must be employed to avoid overlooking an unsuspected aortic arch abnomiality .Key words: double aortic arch, tetralogy of Fallot, atrioventricular septal defect Case ReportA male infant weighing 3.29 kg was bom at term after an uncomplicated delivery to a 21-year-old mother. The infant had clinical features of Down syndrome, which was later confirmed by chromosomal analysis. He was noted to be cyanosed shortly after birth. Cardiac examination confinned central cyanosis and moderate tachypnea, with no signs of upper airway obstruction. The second heart sound was single and there was a short, grade I W I e,:jection systolic mumiur localized to the upper left stcmal edge.Chest x-ray demonstrated cardiomegaly (cardiothoracic ratio 0.58) and normal pulmonary vascular markings. The tracheal air shadow appeared normal. Electrocardiogram revealed a superior axis of -100" with no atrial enlargement and nonnal precordial voltages for age.Echocardiography showed a large ostium primum atrial septal defect, a large ventricular septal defect, and connion atrioventricular valve. The ventricular septal defect extended from the inlet to outlet muscular septum with deviation of the outlet septum and override of a dilated aortic root (Fig. IA). The pulmonary valve was atretic with hypoplastic but confluent pulmonary arteries (Fig. 1 B). There was severe infundibular hypertrophy. Suprastemal views outlined a double aortic arch with ii larger dominant right arch and smaller left arch. The right arch had four branches and the left arch had two ( Fig. 2A, B). A patent arterial duct passed from the underside of the left aortic arch to the left pulmonary artery but n o right patent duct was demonstrated. These echocardiographic findings were consistent with tetralogy of Fallot with pulmonary atresia, complete atrioventricular septal defect, and double aortic arch with left patent arterial duct.The parents declined surgical intervention. The infant has survived and is now 12 months of age. He has not developed stridor, respiratory or swallowing difficulties, but remains severely cyanosed with poor physical growth and markedly delayed developmental milestones. DiscussionA double aortic arch is a rare congenital cardiac abnormality. In 20% of cases, it has been described with other cardiac abnormalities' including ventricular septal defect, aortic coarctation, left patent arterial duct, tetralogy of Fallot,2 complete transposition, and common arterial trunk. l We describe a combination of tetralogy of Fallot with pul-