What is the immediate management for a runaway pacemaker?

Immediate Management of a Runaway Pacemaker

The immediate management of a runaway pacemaker requires placing a magnet over the pacemaker generator to convert it to an asynchronous mode at a lower, more physiological rate. 1, 2

Understanding Runaway Pacemaker

A runaway pacemaker is a rare but potentially lethal complication where a pacemaker malfunctions and paces the heart at dangerously high rates (typically 200-260 beats per minute), causing pacemaker-induced ventricular tachycardia.

Emergency Management Algorithm

First-Line Intervention:

1. Apply a doughnut magnet directly over the pacemaker generator
   • This typically converts the device to an asynchronous mode at a lower rate
   • The magnet should remain in place until definitive management is available
   • All healthcare facilities should have doughnut magnets readily available for emergency use 3

If Magnet Application Fails:

1. Alternative emergency measures (if patient has adequate underlying rhythm):
   • Attempt reprogramming the pulse generator to lower output 1
   • Consider external chest wall overdrive stimulation 1
   • Chest wall stimulation using an external pulse generator 4

If No Adequate Escape Rhythm or Above Measures Fail:

1. Establish temporary pacing:
   • Connect an external pacemaker to the permanent pacing lead 1
   • Or establish temporary transvenous pacing before disconnecting the permanent lead 1

Definitive Management:

1. Urgent pacemaker generator replacement/explantation
   • The malfunctioning device must be exchanged as soon as possible 1, 2

Important Considerations

Monitoring:

• Continuous cardiac monitoring is essential throughout management 3
• Have external defibrillation equipment immediately available 3

Cautions:

• Magnet application may have unpredictable effects on some devices 5
• Some devices have programmable magnet responses with effects other than forcing asynchronous pacing 3
• Verify the effect of magnet placement with ECG monitoring

Prevention:

• Regular device checks are mandatory (every 3-6 months) 6
• Immediate evaluation of any unusual symptoms related to pacemaker function 6
• Ensure proper pacemaker interrogation after procedures with significant electromagnetic interference 6

Special Circumstances

For pacemaker-dependent patients, urgent intervention is critical as they lack adequate escape rhythm. In these cases, establishing temporary pacing before disconnecting the permanent lead is essential to prevent asystole.

Runaway pacemaker is a medical emergency requiring immediate recognition and intervention to prevent hemodynamic compromise and potential death. The most effective and readily available first-line intervention remains magnet application while arranging for definitive management with device replacement.