Cardiac catheterization is a common nonsurgical procedure used to help diagnose a heart problem. During the procedure a thin plastic tube (catheter) is inserted into an artery or vein in the arm or leg, then guided toward your heart. From there it can be advanced into the chambers of the heart or into the coronary arteries.

Once the catheter is in place, x-rays and other tests are done to help your doctor learn how well your heart is working.

This test can measure blood pressure within the heart and how much oxygen is in the blood. It's also used to get information about the pumping ability of the heart muscle. Catheters are also used to inject dye into the coronary arteries. This is called coronary angiography or coronary arteriography. Catheters with a balloon on the tip are used in the procedure called percutaneous transluminal coronary angioplasty (PTCA). Catheterization is also done on infants and children to examine or treat congenital heart defects.