VIENNA, Austria (AP) -- X-rays used during angioplasty can cause severe skin burns, and many cardiologists need more training in how to minimize radiation exposure to patients undergoing the procedures, experts warned on Friday.

The benefits of the operation far outweigh the side effects, but experts from the International Atomic Energy Agency said doctors they must learn how to reduce the radiation risks.

During angioplasty, a catheter attached to a balloon is threaded through the blood vessels to open a blocked artery by squeezing the plaque against the walls. The technique often eliminates the need for open-heart surgery. To guide the catheter to the right spot, doctors use fluoroscopy, a technique that provides live X-ray images.

But the radiation used in fluoroscopy is much stronger than that used in normal X-rays, and a small number of patients suffer skin damage. Some could later develop cancer because of the exposure, said Dr. Madan Rehani, a radiation safety specialist with the IAEA.

The radiation problem is not new -- the U.S. Food and Drug Administration in 1994 alerted U.S. hospitals about the risk for radiation injury in the procedures -- but many cardiologists still lack training about how to handle the radiation danger, Rehani said.

"It is shocking," Rehani said."X-rays have been used for decades safely, so people think they are safe."

He estimated that about one in 10,000 angioplasty patients suffer severe skin injuries -- some so bad that they require skin grafts. About 1 million angioplasties are performed worldwide each year, and the number is growing fast.

Cardiologists should educate themselves about the radiation risks and take steps to reduce them, for example, by keeping the radiation source as far away from the patient as possible, and by moving the beam in extended procedures to avoid exposing the same patch of skin, Rehani said.

Patients with radiation skin burns often are misdiagnosed because their physicians or dermatologists don't see the connection between the skin damage and the fluoroscopy, Rehani said. Early symptoms, which arise days or weeks after the angioplasty, include a rash.

The benefits of angioplasty -- a procedure that is less risky than by-pass surgery and has saved the lives of many heart patients -- far exceed the risks of radiation exposure, said Dr. Guglielmo Bernardi, a cardiologist based in Udine, Italy.

"We can do better and better if we perform the procedure in an optimized way," he added.

The Vienna-based U.N. nuclear agency held a two-day meeting ending Friday to teach cardiologists from 25 mostly developing countries about the problem. Of the 27 cardiologists taking part in the program, 88 percent said the meeting was their first formal training in radiation risks.

The meeting was part of an agency action plan to reduce the radiation dangers facing patients.

Copyright 2004 The Associated Press. All rights reserved.