Cardiac catheterization is a procedure used to diagnose and treat cardiovascular conditions. During cardiac catheterization, a long thin tube called a catheter is inserted in an artery or vein in your groin, neck or arm and threaded through your blood vessels to your heart. Using this catheter, doctors can then do diagnostic tests as part of a cardiac catheterization. Some heart disease treatments, such as coronary angioplasty, also are done using cardiac catheterization.Usually, you'll be awake during cardiac catheterization, but given medications to help you relax. Recovery time for a cardiac catheterization is quick, and there's a low risk of complications.