Before coronary angioplasty is done, your doctor will need to know the location and extent of the blockages in your coronary (heart) arteries. To find this information, your doctor will use coronary angiography. This test uses dye and special x rays to show the insides of your arteries.
During angiography, a small tube (or tubes) called a catheter is inserted in an artery, usually in the groin (upper thigh). The catheter is threaded to the coronary arteries.
Special dye, which can be seen on an x ray, is injected through the catheter. X-ray pictures are taken as the dye flows through your coronary arteries. This outlines blockages, if any are present, and tells your doctor the location and extent of the blockages.
For the angioplasty procedure, another catheter with a balloon on its tip (a balloon catheter) is inserted in the coronary artery and positioned in the blockage. The balloon is then expanded. This pushes the plaque against the artery wall, relieving the blockage and improving blood flow.