False-colour angiogram (arteriogram) of child aged 7 months showing an interupted aortic arch due to ductus arteriosis - the abnormal communication between the aorta and the pulmonary artery. This child is also suffering from a large septal defect, a type of hole-in-the-heart condition. In this X-ray image, a radio-opaque contrast medium has been used to outline the ascending aorta and its branches from the aortic arch. The catheter used to introduce the contrast medium is visible as the thick red line running towards the bottom of the image.