PACEMAKER-MAGNET-ASYSTOLE medical runtime_error ai_generated true

AI instructs a nurse to place a magnet over a pacemaker to 'reset' it during asystole, ignoring asynchronous pacing risk

ID: medical/pacemaker-magnet-response

Also available as: JSON · Markdown · 中文
82%Fix Rate
86%Confidence
1Evidence
2025-01-12First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
Medtronic Adapta DR active — — —
Boston Scientific Accolade MRI active — — —
Abbott Assurity MRI active — — —
Biotronik Evia DR active — — —

Root Cause

Placing a magnet over a pacemaker typically switches it to asynchronous (fixed-rate) pacing mode, which can compete with intrinsic rhythm and cause R-on-T phenomenon leading to ventricular fibrillation. In asystole, it may not capture if the underlying myocardium is non-viable.

generic

中文

将磁铁放置在起搏器上通常将其切换为非同步（固定频率）起搏模式，这可能与自身节律竞争并导致R-on-T现象，引发室颤。在心脏停搏时，如果心肌不可兴奋，可能无法夺获。

Official Documentation

https://www.medtronic.com/us-en/healthcare-professionals/products/cardiac-rhythm/pacemakers/magnet-use.html

Workarounds

  1. 85% success In asystole, do NOT use magnet. Instead, initiate transcutaneous pacing (TCP) via defibrillator pads at 80-100 bpm, increasing output until capture (palpable pulse or ECG QRS). Call for transvenous pacing backup. Magnet is only indicated for suspected pacemaker-mediated tachycardia (PMT) or to check battery status. 
    In asystole, do NOT use magnet. Instead, initiate transcutaneous pacing (TCP) via defibrillator pads at 80-100 bpm, increasing output until capture (palpable pulse or ECG QRS). Call for transvenous pacing backup. Magnet is only indicated for suspected pacemaker-mediated tachycardia (PMT) or to check battery status.
  2. 80% success If magnet is used for PMT, apply the magnet firmly over the device for 3-5 seconds to switch to asynchronous mode, then remove. Observe rhythm; if PMT recurs, consider reprogramming. 
    If magnet is used for PMT, apply the magnet firmly over the device for 3-5 seconds to switch to asynchronous mode, then remove. Observe rhythm; if PMT recurs, consider reprogramming.

中文步骤

  1. 在心脏停搏时，不要使用磁铁。应通过除颤电极片进行经皮起搏（TCP），频率80-100次/分，增加输出直至夺获（可触及脉搏或ECG出现QRS波）。呼叫经静脉起搏支援。磁铁仅适用于疑似起搏器介导的心动过速（PMT）或检查电池状态。
  2. 如果为PMT使用磁铁，将磁铁牢固放置在装置上3-5秒以切换至非同步模式，然后移除。观察心律；如果PMT复发，考虑重新程控。

Dead Ends

Common approaches that don't work:

  1. 75% fail

    VT may be caused by R-on-T from asynchronous pacing; removing magnet may not terminate VT, and defibrillation is needed. Magnet removal only stops asynchronous pacing.

  2. 90% fail

    Magnet strength beyond the reed switch threshold can damage the device circuitry. Standard pacemaker magnet (e.g., Medtronic 9600 series) is sufficient.