Insertable Cardiac Monitors

These devices were a mystery to me for a while. Thanks to a helpful clinic note, it turns out that they're called implantable loop recorders or insertable cardiac monitors (Medtronic Reveal, in this case). The top one had a dead battery and was switched for a newer version (below).

MRI may move the device, but according to Medtronic "the device does not represent a safety hazard." The magnetic field may interfere with the data being stored by the device. Also, "MRI scans should be performed only in a specified MR environment under specified conditions as described in the device manual."

References

Reveal Web Page