Seven infants with aortic valve atresia, seen since real-time echocardiography became available at Dayton Children's Medical Center in 1979, have had similar two-dimensional ultrasonograms. All have had mitral stenosis or atresia, diminutive, thick walled left ventricles, minute aortic valve rings, and ascending aortas with internal diameters of less than 4 mm extending into the suprasternal region. A large right atrium, right ventricle, and large pulmonary arteries were present in all cases. Table III summarizes our approach to the neonate with congestive heart failure and diminished pulses. When aortic valve atresia is demonstrated, medical management is instituted. Infants with abnormal real-time echocardiograms who do not have the characteristic findings of aortic valve atresia are referred for further cardiac evaluation and catheterization. When a normal real-time study is seen, immediate work-up for sepsis, central nervous system disease, and other medical abnormalities is initiated. Two-dimensional...