An angiogram is a diagnostic procedure that uses imaging to show how blood flows through arteries, veins, or the heart. It is a type of X-ray used to examine blood vessels that dont show up clearly on ordinary X-rays, so a special dye is injected into the area being examined. The dye highlights the blood vessels as it moves through them. The procedure is usually done in a hospital and takes between 30 minutes and 2 hours, depending on the complexity of the procedure. During an angiogram, a type of dye thats visible by an X-ray machine is injected into the blood vessels of the area being examined. The X-ray machine rapidly takes a series of images (angiograms), offering a look at the blood vessels. The test is generally done to see if theres a restriction in blood flow going to the area being examined. An angiogram can help diagnose conditions that affect blood vessels and the flow of blood through them, such as blocked or narrowed blood vessels, aneurysms, structural heart or valve disease, and coronary artery disease. Depending on what the doctor discovers during the angiogram, additional catheter procedures at the same time, such as a balloon angioplasty or a stent placement to open up a narrowed artery, may be necessary.