Physician radiation exposure increases during angiography for obese patients

Physicians performing coronary angiography on obese patients are exposed to seven times the amount of radiation than when they performed the procedure on those with a normal body weight, according to a Jan. 2 study published in Circulation: Cardiovascular Interventions.

In the single-center study, physicians from Spectrum Health in Grand Rapids, Michigan, wore dosimeters to measure real-time radiation exposure. In the more than 1,000 coronary angiography procedures, participants with a body mass index (BMI) over 40 experienced a 2.1-fold increase in radiation compared to those with a normal weight, defined as a BMI below 25. However, the physicians imaging those larger individuals experienced a 7-fold increase in radiation dose.

“The greatest source of physician radiation exposure during cardiac catheterization comes from scatter radiation emitted from the patient, which itself is proportional to patient radiation dose,” wrote Ryan D. Madder, MD, with Spectrum Health, and colleagues. “Because greater radiation doses are required to produce adequate images in obese patients, greater amounts of scatter radiation are emitted, and consequently, the obesity epidemic has the potential to alter the occupational risks of physicians performing cardiac catheterization.”

The impact on physicians should be read with “caution,” considering the small number of obese patients may have affected the study, the authors noted.

Madder and colleagues put forth a few explanations for the correlation between increased BMI and physician radiation dosage, including potential difficulties positioning lead shields to block radiation exposure when working with obese patients.  

“The observations made in this study are concerning considering that long-term radiation exposure among interventional cardiologists has been linked to multiple adverse health effects and that the prevalence of obesity in the cardiac catheterization laboratory has been increasing over time,” the authors wrote.

According to the study, Madder disclosed receiving research grants and serving on the advisory board of Corindus Vascular Robotics, which provided partial funding for the study.