Abstract The radiographic findings in twelve cases of persistent left superior vena cava are described. On plain chest films it may present as a widening of the aortic shadow, a paramediastinal bulge, or as a paramediastinal strip or crescent along the upper left cardiac border. Although the left arm vein has been preferred for cardiac catheterization, satisfactory angiocardiographic results were obtained by catheterization of either the saphenous vein or right arm vein in 8 cases. The radiographic appearance of persistent anomalous left vertical pulmonary vein is presented as an aid in differential diagnosis.