Conotruncal malformations: diagnosis in infancy using subxiphoid 2-dimensional echocardiography.

Subxiphoid 2-dimensional echocardiography was performed and interpreted before the first cardiac catheterization of 109 of 113 infants less than 1 year of age with conotruncal malformations, situs solitus of the atria, and d-ventricular loop. The 4 remaining infants could not be examined using this technique for technical reasons. In 104 of 109 patients successfully examined a correct diagnosis was obtained with the use of subxiphoid 2-dimensional echocardiography. All patients with d-transposition of the great arteries had a correct diagnosis, and in 10 of 11 patients various types of double-outlet right ventricle were recognized by direct visualization of ventriculoarterial connection. Tetralogy of Fallot was correctly diagnosed in 34 of 36 patients and tetralogy of Fallot and pulmonary atresia were correctly diagnosed in 8 of 9 patients, on the basis of the position of the infundibular septum and presence or absence of continuity between the main pulmonary artery and the right ventricular. Five of 6 patients with truncus arteriosus communis were correctly diagnosed by demonstrating a connection between the pulmonary arteries and the ascending portion of the single large semilunar root. Subxiphoid 2-dimensional echocardiography proved to be a sensitive and specific technique for diagnosing conotruncal malformations in infancy.