Echocardiographic Findings in Tetralogy of Fallot

Lee, In Sil

Abstract

The echocardiographic features of Tetralogy of Fallot were analysed on 102 patients with Tetralogy of Fallot, proven by cardiac catheterization and angiocardiography. The dimension of the cardiac chambers and the relationship of contiguous structures were determined by M-mode scanning technics. The most characteristic echocardiographic finding of Tetralogy of Fallot was abrupt ending of the interventricular septal echoes with the aorta overriding the ventricular septal defect, and this was present in 94 patients (92%). Additional echocardiographic features were widening of the ascending aorta (82%), right ventricular enlargement (81%), narrowing of the right ventricular outflow tract (100%), hypertrophy of the interventricular septum (60%), dispoprortionate septal thickening (41%) and decrement of left erntricular size (60%). Tetralogy of Fallot can be diagnosed by these combinations of echocardiographic features. The degree of aortic overriding had no correlation with the left ventricular dimension at end-diastole. (r=0.14). The pulmonary-to-systemic flow ratio (Qp/Qs) was correlated with the echocardiographic left atrial-to-aortic root diameter ratio (A/Ao), and a relatively poor correlation (r=0.21) was found.