Researchers recently revealed in a study published in JAMA Network Open that echocardiographers experience significantly higher exposure to radiation than interventional cardiologists. A research team at a Michigan hospital system measured head-level radiation levels for echocardiographers performing particular procedures, which necessitated them to stand near the radiation source and the patient.
Echocardiographers assist interventional radiologists and other physicians who diagnose and treat cardiac problems. Ultrasound equipment provides 2D and 3D images of patients’ hearts as they undergo procedures, including transcatheter edge-to-edge mitral valve repair (LAAO) and left atrial appendage occlusion (TEER) to help prevent strokes. LAAO and TEER require fluoroscopy and transesophageal echocardiography for guidance — necessitating an interventional echocardiographer at many facilities.
Previous studies show that interventional cardiologists who perform LAAO and TEER are at increased risk of radiation exposure; however, no data existed for the echocardiographers. Corresponding author Dr. David McNamara is a cardiologist at Spectrum Health in Grand Rapids. He and his team calculated radiation levels for interventional cardiologists and echocardiographers during 30 consecutive LAAO procedures and 30 consecutive TEER procedures, performed over approximately 18 months. Both interventional cardiologists and echocardiographers wore radiation protection gear — traditional lead skirt, apron, and thyroid collar. The healthcare facility provided 2 shields for the interventional cardiologist — a ceiling-mounted one for the upper body and a lower body shield attached to the operating table reaching the floor.
Radiation Doses during LAAO and TEER
| Procedure | Interventional Cardiologist | Echocardiographer |
| LAAO | 3.5 µSv | 10.6 µSv |
| TEER | 0.9 µSv | 10.5 µSv |
The Occupational Safety and Health Administration (OSHA) established an annualized limit for whole-body radiation exposure of 5 rem (50 mSv), and other countries have stricter exposure limits. While interventional echocardiographers using the shielding techniques in this study would not likely reach annual limits, this study highlights the challenges of rapidly-expanding areas of radiology.
While more study is needed in this area, the study suggests that echocardiographers may be at a similar level of long-term radiation exposure, similar to what’s seen in cardiac catherization laboratories. Adverse side effects in this setting include premature carotid atherosclerosis, earlier onset of cataract development, and the potential for left-sided brain malignant tumors.
Dr. McNamara and his team noted, “Interventional echocardiographers were observed to have median head level radiation doses that were 3.0-fold greater during LAAO and 11.7-fold greater during TEER than for interventional physicians. These comparatively increased radiation doses reveal a previously under-recognized occupational radiation exposure risk.”