An angiogram is an X-ray test that uses a special dye and camera (fluoroscopy) to take pictures of the blood flow in an artery (such as the aorta) or a vein (such as the vena cava). An angiogram can be used to look at the arteries or veins in the head, arms, legs, chest, back, or belly.
Common angiograms can look at the arteries near the heart (coronary angiogram), lungs (pulmonary angiogram), brain (cerebral angiogram), head and neck (carotid angiogram), legs or arms (peripheral), and the aorta (aortogram).
During an angiogram, a thin tube called a catheter is placed into a blood vessel camera.gif in the groin (femoral artery or vein) or just above the elbow (brachial artery or vein). The catheter is guided to the area to be studied. Then an iodine dye (contrast material) is injected into the vessel to make the area show clearly on the X-ray pictures. This method is known as conventional or catheter angiogram. The angiogram pictures can be made into regular X-ray films or stored as digital pictures in a computer.
An angiogram can find a bulge in a blood vessel (aneurysm). It can also show narrowing or a blockage in a blood vessel that affects blood flow. An angiogram can show if coronary artery disease is present and how bad it is.
A magnetic resonance angiogram (MRA) or computed tomography angiogram (CTA) may be an option instead of an angiogram. Each of these tests is less invasive than a standard angiogram. Some MRA tests and all CTA tests require an injection of dye. A CTA also involves radiation exposure.
Why It Is Done
An angiogram is done to:
- Detect problems with blood vessels that affect blood flow. Examples of such problems include a tear in a blood vessel (which can cause blockage or internal bleeding), aneurysms (which are weaknesses in the blood vessel wall), and narrowed areas.
- Look for changes in the blood vessels of injured or damaged organs.
- Show the pattern of blood flow to a tumor. This can not only help show how much the tumor camera.gif has spread but also guide treatment.
- Show the condition, number, and location of renal arteries camera.gif before a kidney transplant.
- Look for a source of bleeding, such as an ulcer.
- Prepare for surgery on diseased blood vessels of the legs (peripheral arterial disease) in people who have severe leg pain when walking.
- Check how bad atherosclerosis is in the coronary arteries.
In some cases, a method called interventional radiology may be used during an angiogram to treat diseases. For example, a catheter can be used to open a blocked blood vessel, deliver medicine to a tumor, or stop intestinal bleeding caused by diverticular hemorrhage. To stop intestinal bleeding, the catheter is moved into the small artery where the bleeding is occurring, and medicine that narrows the artery or causes the blood to clot is injected through the catheter.