Shinebourne E.A.Haworth S.G.Anderson R.H.Ulgur A.2019-10-272019-10-2719740003-9888https://doi.org/10.1136/adc.49.9.729https://hdl.handle.net/11454/24647The ECGs of 473 infants under the age of 3 months who were referred to a paediatric cardiological unit were analysed; 47 (10%) of the ECGs showed a superior axis (dominantly negative deflection S wave, in lead aVF). Of these, the majority of noncyanosed patients with plethora on chest x-ray proved to have either an atrioventricular canal defect or a large ventricular septal defect. When cyanosis and pulmonary plethora on x-ray were present, tricuspid atresia with increased pulmonary flow (types Ic or IIc) or d-transposition with ventricular septal defect accounted for most cases. With cyanosis and pulmonary oligaemia on x-ray, tricuspid atresia (types la and b) or pulmonary atresia with ventricular septal defect accounted for all cases. Finally, 2 patients with superior axis presenting in a shocked condition were found to exhibit the hypoplastic left heart syndrome. Recognition of superior axis in the ECG provides a useful diagnostic aid in congenital heart disease in early infancy.en10.1136/adc.49.9.729info:eu-repo/semantics/openAccessArticle4997297334420177Q1