Echocardiographic diagnosis of tetralogy of Fallot.

The echocardiographic features of tetralogy of Fallot were defined in 25 patients with this malformation proved by cardiac catheterization. The echocardiographic characteristic that was present in all patients and that was most sensitive was the abrupt ending of the interventricular septal echoes with the aorta overriding the ventricular septal defect. The following additional echocardiographic features were frequently demonstrated in these 25 patients: right ventricular enlargement (20 patients), hypertrophy of the interventricular septum (20 patients), diminution of the right ventricular outflow tract (21 patients) and widening of the aorta (24 patients). The suggestion is made that the most specific echocardiographic pattern of tetralogy of Fallot is the finding of several echocardiographic abnormalities rather than the single feature of aortic overriding. Recognition of the altered anatomic relation coupled with a complete echocardiographic evaluation of all cardiac structures is a reliable means of diagnosing tetralogy of Fallot.