Appropriate Classification and Filtering of Electromagnetic Interference by the S-ICD Sensing Algorithm During Surgery

The subcutaneous implantable cardioverter defibrillator (S-ICD) is a new device used for the prevention of sudden cardiac death. Best practices in the perioperative management of the S-ICD are not established; therefore, clinicians typically deactivate the device during surgery, with reinterrogation and activation postoperatively. This could put the patient at risk for being discharged with the device “off.” We present two cases where electromagnetic interference was appropriately detected by the S-ICD and filtered. These cases present an important clinical finding that could lead to less deactivation of devices during surgery. Further research will be required to define which surgical procedures require magnet, reprogramming, or no changes.