Magnet Use for implantable cardiac devices: A Practical Guide

The perioperative management of patients with cardiac implantable electronic devices has significantly improved in recent years. However, the use of the magnet remains insufficiently defined in guidelines, despite variability in device-specific responses across manufacturers and the increasing implantation of leadless devices, whose response to magnet remains poorly understood. Magnet application activates a sensor that triggers asynchronous pacing in pacemakers and disables tachyarrhythmia detection in implantable cardioverter-defibrillators. Although the magnet can safely mitigate the risk of electromagnetic interference in most cases, its application is not always feasible. In high-risk interference scenarios, such as supra-umbilical procedures with unipolar electrocautery in pacemaker-dependent patients, preoperative electrophysiology consultation is essential to consider device reprogramming. In emergency situations, a magnet test before skin incision can help identify the device and guide management.