At the 2015 Society for Cardiovascular Angiography and Interventions Scientific Sessions, Jonathan J. Rome, MD, director of the catheterization laboratories at The Children’s Hospital of Philadelphia, discussed an issue that affects all interventional cardiologists and radiologists: the long-term toll on our bodies resulting from lifetime exposure to radiation and wearing protective equipment.
Fluoroscopy, the modality used for catheter-based interventions, has progressed over the years. The technology has advanced from detectors that operators looked into directly and fixed x-ray tubes that could be lowered toward the patient without collimation to modern digital equipment that allows us to narrow the viewing field, thus reducing radiation exposure to our patients, teams and us. With each iteration, industry has reduced radiation exposure for all of us.
But are these advances enough? Despite our best efforts at radiation safety, do we still undertake unnecessary risks as we care for our patients? A recent study demonstrating the cancer risk that accompanies our endeavors (Am J Cardiol 2013;111:1368-72) suggests we may need to do more. Is it time to consider that fluoroscopy is an outdated imaging modality that has persisted because we have used it so long, developed so many tools to accompany it and invested so much in hospital infrastructures that support it?
Perhaps we can do better. Researchers have begun delving into the possibility of magnetic resonance imaging (MRI)–based interventions. The concept is appealing because radiation would be eliminated and imaging capabilities would be better than with fluoroscopy. However, the limitations are daunting. Put simply, we have no tools. Our field has been built on the use of fluoroscopy, with research and development focused on catheters, wires and devices manufactured to work with fluoroscopy. To transition to MRI, the vast majority of tools would need to be re-constructed with different materials or impregnated with markers that would make them visible with MRI.
The scanners themselves would present challenges. Several years ago, I visited IMRIS, a company in Winnipeg, Ontario, that was partnering with Siemens to build operating room/imaging suites where neurosurgeons could operate and then bring in a MRI scanner via ceiling-mounted tracks to image progress before sending the scanner back to its room. They had decided to expand their product line to include cath lab/MRI suites where the MRI “donut” would move in, image what was needed and then back off. The problem? Pediatric interventional cardiologists would see their newborn and infant patients swallowed up by the magnet. It would allow imaging, but performing procedures with the magnet would require something very different, specifically, something much smaller.
Radiation exposure is often on our minds, but we think less about the toll protective equipment takes on our bodies. Wearing lead to protect ourselves has its own debilitating effects on the spine and joints (J Am Coll Cardiol 2015;65:827-9; Catheter Cardiovasc Interv 2015;86:913-24; J Am Coll Cardiol 2015;65:820-6).
Industry has come to our aid with ever-lighter offerings but, again, has enough been done? If we found ways to reduce use of fluoroscopy, as has been done in electrophysiology, could we eventually feel comfortable hanging up our lead after the initial images are collected?
We know the problem and our tools have improved, but it may be time to stop thinking about how to do better and instead consider ways to change.
John P. Breinholt, III, MD, is a pediatric interventional cardiologist and division director of pediatric cardiology at the University of Texas Health Science Center at Houston.