Complete Atrioventricular Septal Defect with Truncus Arteriosus and Interrupted Aortic Arch in the Fetus.

Complete atrioventricular septal defect is generally diagnosed on the four-chamber view of the fetal heart. This defect can be accompanied by additional outflow tract lesions, including truncus arteriosus. Although truncus arteriosus in isolation can be associated with interrupted aortic arch, we describe a fetal case with the rare association of all three diagnoses: complete atrioventricular septal defect with truncus arteriosus and interrupted aortic arch. This case points to the importance of evaluating the complete fetal heart even after one congenital cardiac abnormality is noted. The complexity of heart disease has implications for prenatal counseling and postnatal management.