This test allows physicians to check the blood flow and blood pressure in the chambers of the heart, find out how well the heart valves work, and check for defects in the way the wall of the heart moves.  In children, this test is used to check for heart problems that have been present since birth (congenital heart defect).

A thin, flexible tube (catheter) is passed through an artery in the upper thigh (groin) or in the arm to reach the coronary arteries. This allows the physician to study the inside of the arteries to look for blockages.

The purpose of cardiac catheterization is to find out if you have disease in your coronary arteries (atherosclerosis).  If you have atherosclerosis, this test can pinpoint the size and location of fat and calcium deposits (plaque) that are narrowing your coronary arteries.  Results from cardiac catheterization help determine whether treatment with bypass surgery or percutaneous coronary intervention (PCI), such as angioplasty, may be effective.