A blocked artery in the heart can lead to chest pain and eventually cause a heart attack. Cardiac catheterization is a procedure that allows cardiologists to see exactly how much damage is in the artery. Cardiac catheterization is a procedure where doctors insert a small catheter into a blood vessel and it’s guided to the heart. An angiogram or an x-ray movie is taken while dye is injected into the arteries to help identify any trouble areas. In the past the femoral artery which is located in the groin was primarily used for these procedures, but through medical advances doctors can now enter through the radial artery in the arm.