Scientific statement encourages discussion of radiation risks before CV imaging

A new scientific statement from the American Heart Association encourages doctors to discuss radiation risks with patients before CV imaging.

“Empowering patients with the knowledge of the benefits and risks of imaging will facilitate their meaningful participation in decisions related to their health care, which is necessary to achieve patient-centered care,” writing group chair Rena Fazel, MD, MSc, FAHA, and colleagues wrote. “Limiting the use of imaging to appropriate clinical indications can ensure that the benefits of imaging outweigh any potential risks.”

The panel recommended that cardiac imaging using CT, radiopharmaceuticals or fluoroscopy should be performed only after the patient is made aware of the clinical justification and expected benefit of the test; all potential risks of the test, including radiation-related risks; and risks and benefits of the alternatives, including no testing.

“The decision to proceed with imaging should be consistent with both current medical evidence and patient values and preferences,” Fazel, cardiologist at Beth Israel Deaconess Medical Center, and colleagues wrote.

The panel cited the following effective communication techniques as potentially helpful:

  • Provide the patient with key facts on the procedure in simple language, highlighting the benefits of accurate diagnosis, early detection and early intervention.
  • Affirm whether the imaging study is appropriate based on appropriate use criteria, highlighting that an appropriate indication means there is a favorable benefit-risk ratio.
  • Create a dialogue, allowing the patient to ask questions.
  • Directly address patient and family concerns on risks of the procedure, including those related to radiation, contrast media and anesthesia.
  • Compare risk estimates from exposure to ionizing radiation to those of everyday procedures such as driving a car.

The panel also recommended that all clinicians requesting cardiac imaging procedures know which ones use ionizing radiation, know basic concepts related to radiation exposure and know typical dose estimates for the most commonly used cardiac imaging procedures. In addition, those performing cardiac imaging procedures should demonstrate adequate knowledge of dose-optimization techniques for patients and dose-minimization techniques for operators and staff.

“The continually expanding repertoire of techniques that allow high-quality imaging with lower radiation exposure should be used when available to achieve safer imaging,” Fazel and colleagues wrote.

The statement was endorsed by the American College of Cardiology, the American Society of Nuclear Cardiology, the North American Society for Cardiovascular Imaging, the Society of Cardiovascular Computed Tomography and the Society for Coronary Angiography and Intervention.

Disclosure: See the full statement for a list of the relevant financial disclosures of the members of the writing group and the reviewers.

A new scientific statement from the American Heart Association encourages doctors to discuss radiation risks with patients before CV imaging.

“Empowering patients with the knowledge of the benefits and risks of imaging will facilitate their meaningful participation in decisions related to their health care, which is necessary to achieve patient-centered care,” writing group chair Rena Fazel, MD, MSc, FAHA, and colleagues wrote. “Limiting the use of imaging to appropriate clinical indications can ensure that the benefits of imaging outweigh any potential risks.”

The panel recommended that cardiac imaging using CT, radiopharmaceuticals or fluoroscopy should be performed only after the patient is made aware of the clinical justification and expected benefit of the test; all potential risks of the test, including radiation-related risks; and risks and benefits of the alternatives, including no testing.

“The decision to proceed with imaging should be consistent with both current medical evidence and patient values and preferences,” Fazel, cardiologist at Beth Israel Deaconess Medical Center, and colleagues wrote.

The panel cited the following effective communication techniques as potentially helpful:

  • Provide the patient with key facts on the procedure in simple language, highlighting the benefits of accurate diagnosis, early detection and early intervention.
  • Affirm whether the imaging study is appropriate based on appropriate use criteria, highlighting that an appropriate indication means there is a favorable benefit-risk ratio.
  • Create a dialogue, allowing the patient to ask questions.
  • Directly address patient and family concerns on risks of the procedure, including those related to radiation, contrast media and anesthesia.
  • Compare risk estimates from exposure to ionizing radiation to those of everyday procedures such as driving a car.

The panel also recommended that all clinicians requesting cardiac imaging procedures know which ones use ionizing radiation, know basic concepts related to radiation exposure and know typical dose estimates for the most commonly used cardiac imaging procedures. In addition, those performing cardiac imaging procedures should demonstrate adequate knowledge of dose-optimization techniques for patients and dose-minimization techniques for operators and staff.

“The continually expanding repertoire of techniques that allow high-quality imaging with lower radiation exposure should be used when available to achieve safer imaging,” Fazel and colleagues wrote.

The statement was endorsed by the American College of Cardiology, the American Society of Nuclear Cardiology, the North American Society for Cardiovascular Imaging, the Society of Cardiovascular Computed Tomography and the Society for Coronary Angiography and Intervention.

Disclosure: See the full statement for a list of the relevant financial disclosures of the members of the writing group and the reviewers.

    Perspective
    Alexandra J. Lansky

    Alexandra J. Lansky

    The most important takeaway of this new AHA statement is raising awareness of the implications of radiation exposure resulting from the many noninvasive and invasive CV diagnostics we put our patients through. This is far from being a trivial concern. It is estimated that more than 3 million patients per year present to primary care doctors or cardiologists with symptoms suggestive of obstructive coronary disease that may require further evaluation with diagnostic tests involving radiation, not to mention other CV conditions leading to additional tests. Also, tests beget more tests, compounding the problem of cumulative radiation exposure. 

    While a lot of the information being highlighted in the statement may already be alluded to in various other guidance documents, this statement is bringing the concerns of radiation exposure to center stage and is a call to action to bring the patient, as well as the clinician, into the decision making process. This is critical. We are not thinking about radiation risk enough when ordering tests for our patients. As the statement recommends, clinicians as well as patients need a better understanding of the topic to make informed decisions. For example, evidence shows that nuclear imaging tests performed to detect suspected CAD more than tripled between 1990 (3 million) and 2002 (9.3 million), despite the fact that objective findings of ischemia declined from 30% (1991) to 5% (2009). This highlights the fact that nuclear stress tests are increasingly being used in patients with progressively lower risk, calling into question appropriate use of testing. Are patients really informed? Probably not!

    The statement also highlights the many challenges of measuring and tracking radiation exposure. The 30 or so reference documents the reader is referred to for further information on the topic highlight the need for next steps: Now that we’ve raised awareness about the concern over radiation exposure from CV tests, we need to take action and follow through on the recommendations. One priority is to have a condensed resource for patients and clinicians to explicitly clarify radiation exposure associated with medical tests and to better understand the impact of their age, gender, repeated tests, etc., on lifetime risk. There’s a real need for such a focused resource.

    The recommendations for optimizing the performance of CV diagnostics, for educating health care providers, including technicians, and for mandating that radiation safety be part of a curriculum earlier on in training are areas that will impact and ultimately minimize radiation exposure. It will take time to implement such measures nationally.

    Tracking radiation exposure in our patients in clinical trials or clinical practice is an important next step to quantify exposure and risk. In practical terms, we must define metrics and implement practical tools for clinicians and patients that would enable precise measures of radiation exposure and lifelong cancer risk. That’s a gap that needs to be filled.

    Noninvasive imaging tests are here to stay; and, as discussed in the statement, optimizing imaging technology is critical in reducing risk. Not mentioned in the statement, however, are newer diagnostic methods that may not expose the patient to radiation. The Corus CAD, as an example, is a validated gene expression test derived from a simple blood test designed to exclude or rule out obstructive CAD that does not expose the patient to any radiation and may optimize the evaluation of our patients while reducing risk. We need to push such innovative diagnostic research forward if we are to have a meaningful impact on reducing our patient’s risk from medical imaging.

    • Alexandra J. Lansky, MD, FESC, FACC
    • Director, Yale Heart and Vascular Clinical Research Program, Yale School of Medicine Associate Professor of Medicine, Yale-New Haven Hospital

    Disclosures: Lansky reports no relevant financial disclosures.