A significant portion of the aging population relies on pacemakers or implantable cardioverter defibrillators (ICDs) to lead healthy lives. In the past, MRI use for those folks who depend on these cardiac electronic devices was deemed unsafe, as the technology could trigger cardiac injury. However, emerging research has found zero risk for patients with pacemakers and defibrillators who undergo MRI at a field strength of 1.5 tesla.
For people with ICDs or pacemakers, MRI scans can produce rapid heart rate, shocks, and damage the implant technology. Although the American College of Radiology considers MRI to be safe in certain cases of people with the cardiac devices, scientists at the MagnaSafe Registry, a center that studies the effects of MRIs on people with ICDs and pacemakers, has found new ways to expand MRI access. The researchers evaluated 1,500 patients who underwent MRI. They utilized a special protocol that incorporates screening, monitoring, and programming the device before the MRI procedure.
Researchers at 19 U.S. institutions developed the protocol by testing 1,000 patients with non-MRI approved pacemakers and 500 patients with non-MRI approved ICDs. They scanned various regions, except for the chest, like the brain, spine, extremities, and other areas where MRI can capture the best images. Scientists turned the pacemaker off if the patient could remain stable without it. If their heart required constant use of the pacemaker, then they set it to a “pacing mode” that didn’t detect cardiac activity.
Study leader Robert Russo, MD, director of The La Jolla Cardiovascular Research Institute, and his team noted that 12 patients experienced adverse effects. Six participants felt atrial fibrillation and six pacemakers lost saved patient information. Yet, there was no sign of device or heart failure in the study.
“Patients with a standard or non-MRI-conditional pacemaker can undergo clinically indicated MRI without harm if a protocol such as the ‘MagnaSafe’ protocol used in this study is followed and patients are screened and monitored as described,” said Russo. Their research was published in The New England Journal of Medicine back in February.