Series of 9 arteriograms of an infant's coronary arteries obtained using digital subtraction angiography (DSA) performed in a U.S. hospital. DSA imaging involves taking an initial x-ray (the arterial details of which are unclear), then introducing a contrast-enhancing dye into the bloodstream, and taking a second x-ray. The images are digitised on a computer and the 1st is subtracted from the 2nd, producing the pictures seen. DSA is better suited to paediatric diagnostics than conventional angiography (expensive, invasive, & traumatic), requires minimal sedation, and can be performed on an out- patient basis.