[Ventricular fibrillation during testing of a demand pacemaker (author's transl)]

Area of Science:

• Cardiology
• Biomedical Engineering
• Electrophysiology

Background:

• Implanted pacemakers are crucial for managing bradyarrhythmias.
• Demand pacemakers adjust pacing based on intrinsic heart activity.
• Testing pacemaker function sometimes involves switching to fixed-rate mode.

Observation:

• Ventricular fibrillation occurred during a pacemaker test.
• The event happened when switching from demand to fixed-rate pacing via magnet.
• The patient had no signs of myocardial infarction, electrolyte imbalance, or digitalis toxicity.

Findings:

• Non-synchronized pacing, even briefly, can induce life-threatening arrhythmias.
• Magnet application for pacemaker testing poses a potential risk.
• This case demonstrates a rare complication of pacemaker management.

Implications:

• Clinicians must be aware of the risks associated with pacemaker mode switching.
• Pacemaker testing protocols may require re-evaluation.
• Patient safety during pacemaker interrogation and testing is paramount.