Cardiac catheterization is used to study the various functions of the heart. Using different techniques, the coronary arteries can be viewed by injecting dye or opened using balloon angioplasty. The oxygen concentration can be measured across the valves and walls (septa) of the heart and pressures within each chamber of the heart and across the valves can be measured. The technique can even be performed in small, newborn infants.

Cardiac catheterization is used to study the various functions of the heart or to obtain diagnostic information about the heart or its vessels. A small incision is made in an artery or vein in the arm, neck, or groin. The catheter is threaded through the artery or vein into the heart. X-ray images called fluoroscopy are used to guide the insertion. When the catheter is in place, dye is injected to visualize the structures and vessels within the heart.