Clinical trial at HonorHealth Research Institute shows substantial drop in laboratory radiation, with most cases producing undetectable radiation exposure to cardiology staff

HonorHealth Research Institute announced today that it is among the first healthcare providers in the U.S., and the first in Arizona, to use an advanced radiation protection system as part of the diagnosis and treatment of heart disease.

Modern cardiac catheterization laboratories use multiple X-ray beams from different angles to produce high-quality images of the heart, major arteries and other tissues. These low-level radiation beams enable physicians to guide catheters and other devices during interventional cardiology procedures, which are non-surgical, catheter-based therapies for patients who do not require open-heart surgery.

While generally considered safe, repeated exposure to low-level radiation over time presents a potential cancer risk to doctors, nurses and other catheterization laboratory staff. Current standard radiation protection for operating room personnel — a lead apron — offers no protection to the head and face, with suboptimal shielding of the extremities, creating a potential risk of cataracts and certain cancers. In addition, the weight of the lead apron has been associated with orthopedic injury of the spine, hips and knees.

In a recently completed study at HonorHealth Research Institute, investigators found that the new radiation protection system called ProtegoÒ significantly reduces overall room radiation, and in most cases eliminates exposure to physicians and nurses. The findings published today in the Journal of the Society for Cardiovascular Angiography & Interventions (JSCAI) may have a profound impact on reducing radiation exposure to healthcare workers. In nearly 70% of the cases, radiation exposure to the physicians and nurses was so low as to be “undetectable” using real-time dosimetry.

Dr. David G. Rizik, director of the Cardiovascular Research Division at HonorHealth Research Institute, likened the use of radiological equipment without the protection of radiation shields to football teams playing without helmets.

“Since the first college football game in 1869, there have been dramatic equipment improvements to enhance the safety of the game and reduce injury to athletes. Yet, interventional cardiology — one of the most advanced fields of medical science over the last half-century — has made no substantive changes in how to protect physicians and nurses who perform interventional procedures,” said Dr. Rizik, who served as the clinical trial’s principal investigator and lead author of the study published today in JSCAI. “I am so very proud that HonorHealth is leading the way in this important field of research.”

The study by HonorHealth Research Institute — the world’s first side-by-side comparison of standard protection compared to the ProtegoÒ system — also suggests that the radiation reduction may eliminate the need for cardiac catheterization laboratory staff to wear the orthopedically burdensome lead aprons. The new system allows physicians complete freedom of movement, the study said.

An editorial in today’s JSCAI encouraged physicians and physician-led organizations to “demand this level of protection for themselves and their staff.” Adopting the radiation protection system could promote the recruitment of physicians and critically needed medical staff by easing their concerns over both radiation exposure and reducing or removing the discomfort they suffer when required to wear heavy lead-lined garments.

Risks to healthcare professionals

A study published in the American Journal of Cardiology suggests a link between brain tumors and occupational radiation exposure. A study cited in today’s JSCAI editorial notes that interventional cardiologists have a three-fold higher risk of developing cataracts than the general population. And, those working in catheterization laboratories for 20 years or more are estimated to have received the equivalent of more than 10,000 chest x-rays to the head and neck.

Results of HonorHealth Research Institute’s clinical trial showed that — of the 25 interventional cases completed using the ProtegoÒ system — 17 recorded undetectable radiation exposure, and 4 cases measured 0.1 millirem (mR) of total exposure, only about 5% of the 2.0 mR/hour maximum considered safe.

Interventional cardiologists specialize in treating coronary artery disease, heart valve disorders, congenital heart disease, and other heart problems. With equipment modifications for specific applications, these findings may confer workplace benefit to other physicians working in specialties exposed to radiation, including rhythm management specialists (electrophysiologists) and radiologists.

The required lead aprons worn in catheterization laboratories can weigh as much as 15 pounds and place up to 300 pounds psi on intra-vertebral disks. According to the Society of Interventional Radiology, 70 percent of interventional cardiologists experience lower back pain, 40 percent experience neck pain and 42 percent experience both.

“Use of this groundbreaking radiation protection system is a first in Arizona. This system will especially protect the next generation of physicians and researchers,” Dr. Rizik said. “It will help protect the lives of those on the front lines of lifesaving cardiovascular therapies and is literally getting the lead off our backs.”

Mark A. Slater, Ph.D., CEO of the HonorHealth Research Institute, praised the adoption of the new radiation protection system.

“The issue of radiation exposure to physicians and catheterization laboratory staff has largely been ignored over the past 30 years. While we’ve seen dramatic technological advances in heart treatments, there have been few improvements in our ability to protect our physicians and nurses from the deleterious effects of radiation exposure,” said Dr. Slater, who also is HonorHealth’s vice president of research.

“The JSCAI article essentially demonstrates that there is a dramatic, statistically significant reduction in radiation exposure to staff using the ProtegoÒ system,” added Dr. Slater. “Accelerating medical innovation to enhance safety, quality of care, and patient outcomes is core to the mission of HonorHealth Research Institute.”

Dr. John Neil, HonorHealth’s executive vice president, chief physician executive and network strategy officer, was a practicing clinical vascular and interventional radiologist for two decades.

“The challenge of radiation exposure to those who work in the interventional lab is an issue that hits very close to home,” Dr. Neil said. “I am proud and appreciative of the groundbreaking work done by Dr. Rizik and the team at HonorHealth. Our Mission is to protect the health and well-being of those we serve, and that includes protecting the health and well-being of those who dedicate their professional careers to saving lives and caring for others.”

Also contributing to this study from the HonorHealth Research Institute were: Dr. Robert D. Riley; Dr. Robert F. Burke; Sabrina R. Klassen; Ariana M. Nigoghosian; Kevin P. Gosselin, Ph.D.; and Dr. James A. Goldstein. Dr. Goldstein is an equity owner and board member of ECLS Inc., which licenses technology to Image Diagnostics Inc., which makes the Protego shield.