Most interventional cardiologists don’t fully grasp radiation risks

PARIS – What most interventional cardiologists and electrophysiologists do not know about their health risks due to occupational radiation exposure and how best to protect themselves could fill a book – or better still, make for an illuminating 2-hour expert panel discussion at the annual congress of the European Association of Percutaneous Cardiovascular Interventions.

“There’s a problem of lack of awareness on the part of interventional cardiologists, and also of institutional insensitivity to the problem,” declared Emanuela Piccaluga, MD, an investigator in the eye-opening Healthy Cath Lab study. This Italian national study showed that cardiac catheterization laboratory staff had radiation exposure duration–dependent increased risks of cataracts, cancers, and skin lesions, as well as other radiogenic noncancer effects: anxiety and depression, hypertension, and hyperlipidemia.

^{Bruce Jancin/Frontline Medical News}

Emanuela Piccaluga, MD

Cardiologists at some European hospitals have to pay for their own lead aprons and other protective gear. And even if the hospital does pick up the bill, administrators often balk at authorizing replacement of a lead apron that has developed microfractures and cracks. They view these imperfections as cosmetic defects, unaware that the damage renders the apron less protective, according to Dr. Piccaluga of Niguarda Ca’ Granda Hospital in Milan.

Ariel Roguin, MD, head of interventional cardiology at Rambam Medical Center in Haifa, Israel, said every cardiologist working with radiation should understand the three principles of radiation reduction, which he refers to in shorthand as “TDS,” for Time, Distance, and Shielding. Radiation is here to stay in cardiology, he said, but interventionalists can maximize their safety by keeping the fluoroscopy time and number of acquired images down, standing as far away as possible from both the radiation source and patient while still getting the job done well, and using appropriate shielding routinely.

Dr. Roguin gained notoriety with his report that 26 of 30 interventional cardiologists with glioblastoma multiforme or other brain malignancies had left-hemisphere cancers and 1 had a midline malignancy; only 3 were right-sided (Eur Heart J. 2014 Mar;35[10]:599-600). That distribution is highly unlikely to be due to play of chance, given that an interventional cardiologist’s left side is the side that’s usually exposed to more radiation.

^{Bruce Jancin/Frontline Medical News}

Ariel Roguin, MD

“We should form a wall against radiation. Apart from the leaded aprons, for every procedure we all should also use lead skirts going from the table to the floor to block backscatter, ceiling-mounted overhead radiation shields, special glasses to protect against cataracts, and thyroid collars. And it’s very important to wear a dosimeter with sound; it helps increase awareness of our exposure,” he said.

Dr. Roguin has been a pioneer in the use of a thin, 0.5-mm lead shield draped across the patient’s abdomen from the umbilicus down during radial-access angiography. In a 322-patient randomized trial, he and his coinvestigators showed that this practice results in a threefold reduction in radiation to the operator, albeit at the cost of doubling the patient’s radiation exposure (Catheter Cardiovasc Interv. 2015 Jun;85[7]:1164-70).

“We now routinely do our radials with the lead apron across the patient’s abdomen. We’ve reached the conclusion that we work with radiation in the cath lab every day for many years and the patient is there only once or twice in a lifetime, hopefully,” the cardiologist explained.

With the growing popularity of radial-access interventions, audience members wanted to know if there is an advantage in terms of radiation exposure to left versus right radial artery access. The answer is no, according to Dr. Roguin.

“There are several studies showing no difference in radiation exposure. Left radial artery access is faster, but you’re leaning on the patient and getting more radiation as a result, while with right radial access you have to do more catheter manipulation, which takes longer. Both approaches involve more radiation to the operator than the transfemoral approach,” he said.

Dr. Piccaluga presented highlights from the Healthy Cath Lab study, sponsored by the Italian Society of Invasive Cardiology and the Italian National Research Council’s Institute of Clinical Physiology. The study involved detailed self-administered questionnaires completed by 218 interventional cardiologists and electrophysiologists, 191 nurses, and 57 technicians regularly exposed to ionizing radiation in the cardiac cath lab for a median of 10 years, along with 280 unexposed controls.

A variety of health problems were more frequent in the cath lab personnel regularly exposed to radiation. Rates were consistently highest in the cardiologists, followed next by the cath lab nurses, and then the radiation technicians.

Rates of health problems were highest in the 227 individuals with at least 13 years of cath lab radiation exposure. For example, their adjusted risks of cataracts, hypertension, hypercholesterolemia, and cancers were respectively 9-, 1.7-, 2.9-, and 4.5-fold fold greater than in unexposed controls, as detailed in a recent report (Circ Cardiovasc Interv. 2016 April. doi: 10.1161/CIRCINTERVENTIONS.115.003273).