Two-dimensional echocardiographic features of interruption of the aortic arch.

The 2-dimensional echocardiographic features of interruption of the aortic arch are presented based on analysis of the echocardiograms and angiograms from 8 infants: 2 with type A and 6 with type B interruption. Each infant had a patent ductus arteriosus, 6 had a conoventricular septal defect with leftward deviation of the conal septum, 1 had truncus arteriosus with truncal valve stenosis, and 1 had a distal aortopulmonary septal defect with an intact ventricular septum. Echocardiographic images obtained from the suprasternal notch or from a high parasternal approach demonstrated the interruption of the aortic arch and continuation of the patent ductus arteriosus into the descending aorta. These findings were compared with those in infants with aortic atresia and a hypoplastic ascending aorta or discrete coarctation of the aorta with tubular hypoplasia of the aortic arch. Types A and B interruption of the aortic arch were easily differentiated and the caliber of the patent ductus arteriosus was assessed. The characteristic conoventricular septal defect was readily visualized froma an apex 2-chamber view or from a subcostal sagittal plane view. With this information subsequent angiography can be more expeditiously performed in this group of critically ill infants.