MRI-safe pacemaker 100 percent free of adverse events in clinical trial

A clinical trial involving Biotronik’s ProMRI pacemaker has shown the model is safe for use during head and lower-back MRI scans, according to results published in the journal Heart Rhythm.

The study evaluated 226 patients implanted with the ProMRI device who underwent head and lower-lumbar MRI scans and participated in a one-month follow up examination. Endpoints of MRI-based Serious Adverse Device Effects (SADE), MRI-induced threshold increase, and P- and R- wave attenuation were recorded and evaluated.

The results showed the ProMRI implant had a 100 percent SADE-free rate, with no adverse effects reported following the MRI scan. “Pacing threshold and sensing amplitude changes from immediately before the MRI to the 1 month post MRI visit was clinically stable and unchanged,” wrote lead author William M. Bailey, MD, FHRS, of Lafayette-based Louisiana Heart Specialists, and colleagues. “There was no evidence of adverse impact on either the patient or the pacemaker system caused by MRI scanning.”

Patient-safety will continue to be the impetus for research into MRI-safe pacemaker technology, says Bailey and his colleagues. “As the MRI scanner technology advances, more safety studies and device modifications will be needed to maintain safety with more powerful scanners, and new scan protocols and sequences,” the authors wrote. “This pacemaker and system is expected to facilitate and increase pacemaker patient access to receiving quality diagnostic MRI imaging.”

Historically, patients with permanent pacemaker implants have been restricted from receiving MRI services, as strong radiofrequency fields can damage device and lead functionality and result in physical harm and even death. Since it is estimated that 50-75 percent of those patients will need MRI scans at some point during their lives, momentum for the development of MRI-safe pacemakers has driven research at medical manufacturing firms worldwide.