An angiogram is an X-ray test to detect any enlargement, narrowing or blockages in the blood vessels. The lungs, heart, brain, neck, legs and arms are common areas of concentration during an angiogram. An angiogram can be used to detect and diagnose certain medical conditions including coronary heart disease, angina, myocardial infarction and portal hypertension – among others. If your doctor or physician suspects any of these, they may request that you have an angiogram.