Once the catheter is placed in the opening, or ostium, of one of the coronary arteries, the doctor injects dye and takes a series of x-rays of the artery. Areas of narrowing or blockage in the coronary artery can be seen on the x-rays.
Reviewed By: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.