Cardiac (heart) catheterization is also known as cardiac “cath” or coronary angiography. During this test the doctor puts a thin plastic tube into a blood vessel in your leg or arm and moves it up to your heart. Then the doctor injects a fluid through the tube to the heart. The fluid shows up on X-ray and can show whether any of the arteries in your heart are clogged.
In this test, a short tube (sheath) is inserted into a vein or artery in your leg (groin) or arm. A hollow, flexible and longer tube (guide catheter) is then inserted into the sheath. Aided by X-ray images on a monitor a doctor threads the guide catheter through that artery until it reaches your heart. The pressures in your heart chambers can be measured, and dye can be injected. The dye can be seen on an X-ray, which helps a doctor see the blood flow through your heart, blood vessels and valves to check for abnormalities.