Limiting Radiation Exposure in Heart Exams
Cardiology procedures may expose patients to more radiation than is necessary
(dailyRx News) Cardiologists often rely on imaging techniques involving radiation. Some patients, however, may be exposed to unnecessary and harmful doses of radiation.
Imaging exams with computed tomography (CT), fluoroscopy (real-time X-ray imaging) and nuclear medicine present both benefits and risks. While they can improve diagnosis and lead to life-saving treatment, they also can elevate a person’s risk for developing cancer.
A new position paper from the European Society of Cardiology (ESC) urges cardiologists to reduce the high rate of inappropriate examinations and excessive radiation doses in appropriate examinations.
Eugenio Picano, MD, senior medical researcher for the Italian National Research Council, director general of the Echocardiographic Laboratory at the Institute of Clinical Physiology in Pisa and scientific director of the Montevergine Cardiology Clinic in Mercogliano, Italy, served as lead author of this document for the ESC Associations of Cardiovascular Imaging, Percutaneous Cardiovascular Interventions and Electrophysiology.
This paper outlined doses and risks of cardiology examinations used frequently in diagnosing and treating heart disease.
Procedures that are performed daily in all cardiology in- and out-patient departments may deliver a radiation dose equivalent to 750 chest X-rays, according to the authors. These techniques include CT (an imaging method that uses X-rays to create pictures of cross-sections of the body), electrophysiology methods that measure electrical activities in the heart and nuclear radiology tests that require a small amount of radioactive tracer, which is injected into a vein and is taken up by the heart.
Sarah Samaan, MD, cardiologist and physician partner at the Baylor Heart Hospital in Plano, Texas, told dailyRx News that nuclear stress tests are often used by cardiologists to evaluate blood flow in the heart arteries without having to put a catheter inside the heart.
“These tests are a mainstay of cardiology, but they do expose the patient to a substantial amount of radiation,” she said. “I would advise people to ask their doctor if there are alternatives to a stress test or other procedure that involves radiation exposure. While sometimes a test that involves radiation is truly the best option, often there are options that provide virtually the same information with less risk.”
Dr. Picano and his colleagues also reviewed the radiation exposure involved with percutaneous coronary intervention (PCI), a common procedure used to open blocked coronary arteries. To perform PCI, a doctor directs a catheter with a small balloon at its tip through a blood vessel. To locate the blocked area, fluoroscopy (similar to an X-ray “movie”) is used. The artery is opened by inflating the balloon and compressing the fatty tissue.
The authors of this paper stated that a PCI procedure increases lifetime risk of fatal and non-fatal cancer in a range from 1 in 1,000 to 1 in 100 for a healthy 50-year-old man. Compared to men, risks are 1.38 times higher in women and four times higher in children, who have cells that divide more quickly and have more years in which to develop cancer.
“Unfortunately, radiation risks are not widely known to all cardiologists and patients and this creates a potential for unwanted damage that will appear as cancers, decades down the line,” said Dr. Picano in a press release. “We need the entire cardiology community to be proactive in minimizing the radiological friendly fire in our imaging labs.”
Dr. Picano estimated that 30 to 50 percent of these cardiovascular exams are totally or partially inappropriate. In some cases, the exams may be appropriate but the dose of radiation is more than recommended — sometimes two to 10 times greater than the expected amount.
He advised patients to protect themselves by not self-prescribing screening examinations promoted by irresponsible advertisers and by asking their doctor about the radiation dose they are likely to get from an examination.
“The smart patient, and the smart cardiologist, cannot be afraid of radiation since it is essential and often life saving,” said Dr. Picano in a statement. “But they must be very afraid of radiation negligence or unawareness. This paper will help to make cardiology wards and laboratories a safer place for patients and doctors through an increase of radiation awareness and knowledge.”
The paper was published January 8 in the European Heart Journal.
January 8, 2014
European Heart Journal, “The appropriate and justified use of medical radiation in cardiovascular imaging: a position document of the ESC Associations of Cardiovascular Imaging, Percutaneous Cardiovascular Interventions and Electrophysiology”European Society of Cardiology, “Cardiologists urged to reduce inappropriate radiation exposure”U.S. Food and Drug Administration, “White Paper: Initiative to Reduce Unnecessary Radiation Exposure from Medical Imaging”Johns Hopkins Medicine, “Percutaneous Coronary Intervention (PCI), Coronary Angioplasty, and Stent Placement”© Tyler Olson | Dreamstime.com
January 9, 2014