The procedure itself will take approximately 30 minutes to 1 hour. Mild sedation may be given. During angiography, a long slender tube called a catheter is inserted into the artery (generally, in the groin area). The catheter is slowly maneuvered through the artery until its tip reaches the segment of vessel to be examined by angiography. A small amount of contrast material is injected into the blood vessel segment through the catheter, and X-rays are taken. The contrast agent enables the blood vessels to appear on the X-ray pictures. A physician specially trained in angiography studies the X-ray pictures to determine the source of the problem and the extent of damage to the blood vessel segments that are examined.