Benefits of Cardiac CT Imaging may Outweigh Risk
According to a new study, the benefits of cardiac CT imaging (computed tomography (CT) angiography, or CCTA) may outweigh the risks. The results show that education and quality improvement are needed to ensure patients are protected from cancer risk associated with the increased use of 64 slice CT heart scans used in emergency rooms to detect heart disease in patients with chest pain.
The study, published February 4 in the Journal of the American Medical Association (JAMA), cautions against the small, but potential risk of cancer associated with high doses of radiation used during cardiac CT scans.
The authors write, "With the constantly increasing number of CCTA-capable scanners worldwide, the volume of CCTA scans performed is likely to show substantial further increase." Researchers conducted a study, measuring the risk of radiation from cardiac CT scans, finding that CCTA exposes patients to radiation amounts equal to 600 chest x-rays.
The trial, called the Prospective Multicenter Study On Radiation Dose Estimates Of Cardiac CT Angiography In Daily Practice I (PROTECTION I), analyzed factors and the amount of radiation from cardiac CT testing in 1,965 patients undergoing CCTA.
The authors say…" the study demonstrates that radiation exposure can be reduced substantially by uniformly applying the currently available strategies for dose reduction, but these strategies are used infrequently. "As CCTA is being used more frequently worldwide for diagnosing coronary artery disease, all strategies for reducing radiation exposure will finally reduce the patient's lifetime cancer risks. Although the associated risk is small (estimated lifetime attributable risk of death from cancer after an abdominal CT scan is 0.02 percent) relative to the diagnostic information for most CT studies, this risk needs to be realized especially when repeated CT scans are being performed."
CCTA, otherwise known as CT angiography, is useful for diagnosing heart disease, but the researchers caution that measures to decrease the risks from radiation are not widely used. The results show the need to educate physicians and technicians about how to keep patient safe from the high radiation doses delivered during cardiac CT imaging in order to reduce the risk of cancer from cardiac CT heart scans.
In an accompanying editorial, Andrew J. Einstein, M.D., Ph.D., of the Columbia University College of Physicians and Surgeons, New York says, …"the findings suggest that dose-reduction methods can be used in the majority of patients, which should serve as a wake-up call to cardiac CT laboratories that do not routinely use these methods.
Dr. Einstein emphasizes the importance of quality improvement programs to ensure patient protection. Careful evaluation to weigh the benefits versus risk of high radiation associated with cardiac CT imaging (CCTA) is an important consideration for physicians.