Device-device interference triggered by an abandoned pacemaker: a case report.

Background: Cardiac implantable electronic devices (CIEDs) are prone to electromagnetic interference. Common sources include household electronics and industrial machinery. However, medical equipment can also trigger interferences and cause CIED malfunction. Case summary: We report on a 79-year-old male with sudden onset of presyncope. He has a long history of device therapy, including an active VVI leadless pacemaker and an abandoned abdominal pacemaker with epicardial leads. Automatic reactivation of the abandoned pacemaker due to reaching end-of-life mode led to interaction with the active pacemaker, inhibiting it in its function. Due to elevated capture threshold and insufficient output, pacing by the reactivated pacemaker was accompanied by intermittent loss of myocardial capture and patient symptoms. By changing the mode to VOO and increasing the pacing rate of the active pacemaker, the interaction was prevented as an intermittent solution. The final therapy consisted of explanting the pulse generator of the abdominal pacemaker. Discussion: We present a patient with a deactivated abandoned cardiac pacemaker, which self-activated after reaching end-of-life mode and triggered an interaction with his active pacemaker. This case emphasizes the importance of explanting old devices to avoid potential interaction.