This article waslast modified on July 10, 2017.
Medical procedure used to widen blood vessels that have been narrowed or blocked.  During the procedure, a balloon-tipped catheter is inserted into the body (usually through a small incision in the groin). The catheter is guided to the site of the blockage using X-rays and injected dye. The balloon on the catheter is then gently inflated to flatten the blockage and open the blood vessel.