AI指示护士在心脏停搏时将磁铁放置在起搏器上以“重置”它，忽略非同步起搏风险
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
版本兼容性
| 版本 | 状态 | 引入 | 弃用 | 备注 |
|---|---|---|---|---|
| Medtronic Adapta DR | active | — | — | — |
| Boston Scientific Accolade MRI | active | — | — | — |
| Abbott Assurity MRI | active | — | — | — |
| Biotronik Evia DR | active | — | — | — |
根因分析
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。
English
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.
官方文档
https://www.medtronic.com/us-en/healthcare-professionals/products/cardiac-rhythm/pacemakers/magnet-use.html解决方案
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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。
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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。
无效尝试
常见但无效的做法:
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75% 失败
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.
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90% 失败
Magnet strength beyond the reed switch threshold can damage the device circuitry. Standard pacemaker magnet (e.g., Medtronic 9600 series) is sufficient.