Device-related alert message: de-activated ventricular classification

Tracing
N° 4
Manufacturer Biotronik Device Remote monitoring Field Messages and events
Patient

This 43-year-old man received a Lumax 340 VR-T single chamber defibrillator for hypertrophic cardiomyopathy with episodes of sustained ventricular tachycardia. He underwent elective surgery on a salivary gland.

Graph and trace

Telemedicine report

Within 24 h after his return home, a systematic alert message was transmitted warning that the detection arrhythmias had been turned ‘off’ (red color status).

Comments

This patient underwent elective surgery, in which case 2 choices were available:

  1. apply a magnet over the defibrillator throughout the procedure, inhibiting all therapies and preventing the memorisation of the artefacts. If the magnet is applied continuously, the therapies are inhibited for a maximum of 8 h. If the inhibition needs to be prolonged beyond 8 h, the magnet must be removed for a few seconds and reapplied.
  2. deactivate or turn ‘off’ the detection and the defibrillator therapies to prevent the delivery of shocks during the use of an electric scalpel. This second method was chosen for this patient who saw his cardiologist 24 h before undergoing surgery. The detection of episodes was turned off, in order to prevent overloading of the device memory and intraoperative delivery of therapy. The previous programming could be restored by reprogramming the detection.

In this case, the detection was turned off before surgery, and the defibrillator was neither interrogated nor reprogrammed at the end of the operation. This could have had catastrophic consequences, had a serious arrhythmia developed. Telemedicine enabled the early diagnosis of this management error, the patient was called in the next day, and the detection and therapies were programmed back ‘on’. This example illustrates one of the advantages of remote follow-up. This patient would not have been protected by his defibrillator for several months had he been seen exclusively for standard face-to-face ambulatory visits.