Implantable Cardiac Devices, Abandoned Leads Pose Little Risk in MRI

Use of magnetic resonance imaging (MRI) in patients with electronic implantable cardiac devices and abandoned leads appears to be safe, according to research presented at the Heart Rhythm Society’s 38th Annual Scientific Sessions, May 10-13, in Chicago, Illinois.

It has been thought that abandoned leads may act as antennae in patients, resulting in tissue heating and induction of arrhythmias.

The investigators previously reported feasibility in 19 patients. For the present study, they reviewed the database of patients with electronic implantable cardiac devices who underwent MRI at the Mayo Clinic in Rochester, Minnesota, between 2008 and 2016 and added paired (before/after) troponin I assessment to screen for myocardial damage.

A total of 57 patients underwent 70 MRI scans with electronic implantable cardiac devices in situ and 63 abandoned leads. Paired troponin measurements were available in 35 patients (39 MRIs). The median patient age was 66 years, and 63.2% were men.

The investigators found no clinical or electrical evidence of device dysfunction or arrhythmias or pain during the MRI scans. There was a mean difference of 0.002±0.006 ng/mL between pre- and post-imaging. After adjustments for total number of leads per patient, total number of coils, location of abandoned lead (atrial vs ventricular), and lead type (passive vs active fixation), no differences were present.

“MRI appears safe in patients with [electronic implantable cardiac devices] and abandoned leads when performed with careful monitoring,” the investigators concluded. “There was no evidence of myocardial injury as measured by paired troponins.”

Reference

Padmanabhan D, Kella DK, Mehta R, et al. Safety of magnetic resonance imaging in patients with legacy pacemakers and defibrillators and abandoned leads. Presented at: Heart Rhythm Society’s 38th Annual Scientific Sessions. May 10-13, 2017; Chicago, Illinois.