An unusual intracardiac electrogram showing cause for false electrical discharge from an ICD
Ishaq Mohammed1, Karim Ratib, John Creamer
1Department of Cardiology/Medicine, West Midlands Deanery, Birmingham, UK. ishaq.mohammed@nhs.net
BMJ Case Reports
|August 6, 2013
Summary
A rare case shows implantable cardioverter defibrillators (ICDs) delivering inappropriate therapy. Diathermy caused false sensing of ventricular fibrillation (VF), leading to unnecessary shocks during surgery.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Devices
Background:
- Implantable cardioverter defibrillators (ICDs) are crucial for managing life-threatening arrhythmias.
- Surgical procedures, especially those involving sternal wires, may require electrocautery devices like diathermy.
- Potential interactions between medical devices and surgical equipment require careful consideration.
Observation:
- A patient undergoing surgical removal of sternal wires under general anesthesia experienced inappropriate ICD therapy.
- The inappropriate therapy was triggered by electromechanical interference.
- This interference was falsely interpreted by the ICD as ventricular fibrillation (VF).
Findings:
- Diathermy, a surgical tool, generated electromagnetic interference during the procedure.
- The ICD's intracardiac electrogram demonstrated this mechanical interference.
- The device incorrectly identified the interference as VF, leading to shock delivery.
Implications:
- This case highlights a rare but significant complication of ICD therapy.
- It underscores the importance of awareness regarding potential diathermy interference with ICDs.
- Further research and device programming adjustments may be needed to prevent such events in surgical settings.
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