Radiation in heart procedures tied to cancer risk


New member
People who undergo radiation-based tests and procedures after a heart attack may have a heightened risk of developing cancer down the road, a study published Monday suggests.

Researchers found that among nearly 83,000 Canadians who'd suffered a heart attack, the risk of developing cancer over five years inched up along with the patients' exposure to radiation from heart procedures.

For every additional 10 millisieverts (mSv) in cumulative radiation dose received, the study found, the risk of developing cancer rose by 3 percent.

The common radiation-based procedures that heart attack patients undergo -- including nuclear stress tests, heart catheterization and, increasingly, CT scans of the heart -- typically deliver a radiation dose of between 5 and 15 mSv.

The study, published in the Canadian Medical Association Journal, is the latest to raise concerns about people's increasing exposure to radiation from medical imaging. Growth in individuals' potential lifetime radiation exposure has been driven largely by the growing use of CT scanning, which employs X-rays to produce three-dimensional images of the body, and nuclear medicine tests -- wherein a small amount of radioactive material is injected into the bloodstream, concentrates in various tissues and is then read by special cameras.

However, the researchers stress that the cancer risk detected in the new study is small.

They say the findings should not scare heart disease patients away from needed procedures -- certainly not from the potentially lifesaving catheterization procedures that might be done to treat a heart attack in progress.

During catheterization, a thin tube is threaded into the arteries leading to the heart and special X-ray images allow the doctor to locate any blockages; those blockages can then be cleared using a balloon-tipped catheter -- a procedure known as angioplasty.