Recently, Jack wrote about his views on radiation risks and the need to balance concerns about radiation dose with getting a test done that could reverse a life-threatening condition. Yesterday, a study came out in JACC that finds that cardiac imaging procedures increased risk of radiation exposure and effective doses for those in the study.
Of the 952,420 patients in the study, which were nonelderly adults with continuous enrollment in United HealthCare, 9.5% underwent at least one cardiac imaging procedure associated with radiation exposure over the three years of the study. The mean cumulative effective dose for these patients was 23.1 mSv, with a median dose of 15.6 mSv.
However, as the authors note in their discussion:
“The public health and clinical implications of radiation exposure from cardiac imaging are not easily determined. Clinicians and patients must consider tradeoffs between the benefits of cardiac imaging procedures and their potential long-term risks due to radiation.”
They also note that while “radiation exposure from cardiac imaging procedures may be worth the risk for many patients,” many of the younger patients in the study “may be candidates for alternative imaging modalities that do not use ionizing radiation but provide similar clinical information for informed decision making.”
Accompanying the JACC article is an editorial comment that questions the assumptions of the study. The authors write:
“...[T]he entire premise that radiation doses from medical testing causes cancers remains hypothetical. ... [T]he relationship between low-dose medical imaging and harm has never been established.”
They conclude: “We need to move beyond radiation models, with so many assumptions, to studies documenting the real risk (if any) to the cardiac patient.”
Each of the articles raises important points. On the one hand, patients are being exposed to long-term risks associated with radiation. On the other, we’re not really sure how much of a problem these risks are. Clearly, more research is needed to understand radiation risks in patients: how much radiation puts them at increased cancer risk; how much is the increased risk; and are the tests being performed appropriate.
The ACC has taken a multi pronged approach to ensuring radiation safety, including:
- Setting standards through laboratory accreditation programs, appropriate use criteria (AUC), clinical practice guidelines and other standards documents;
- Developing requirements for training programs and competency, including how to minimize radiation doses during testing and procedures; and
- Implementing quality improvement programs aimed at lowering the dose for each scan or procedure performed. Approaches to minimizing dose include using AUC to eliminate unnecessary scanning procedures; following the principle of “as low as reasonably appropriate” (ALARA) with respect to radiation levels; displaying dose information wherever studies are done; and encouraging facilities to monitor delivered doses and compare them with benchmarks.
Through these efforts, and by working with the American College of Radiology (ACR) and other specialties, we can ensure that patients are receiving the most appropriate and safe treatment possible.
Meanwhile, patients need to become more involved in their care, in particular understanding the risks of undergoing imaging and weighing their imaging options. The more patients are able and willing to be involved, the more they are able to weigh the risks and benefits. The ACC currently has its patient education portal, CardioSmart, to assist providers with educating patients about their different imaging options. We hope to include more about radiation risks in the future.
Ultimately, the idea is for physicians and patients to work together to determine the appropriate treatment or test. Such decisions would include a discussion of radiation-related concerns as compared to the risks and benefits of the different diagnosis or treatment options and could lead to better patient understanding of potential side effects.
For more about ACC’s commitment to patient safety in medical imaging, read ACC’s patient safety briefing on CardioSource.
Your turn: Do you think that imaging procedures put patients at undue risk? What’s the best way to mitigate these risks?
UPDATE (7/9): Two mainstream news articles covered the article: