2026 Volume 46 Issue 2 Pages 133-140
A 60-year-old man with a Brugada-type electrocardiogram and prior syncope underwent an electrophysiological study, during which ventricular fibrillation（VF）was induced. As a result, an implantable cardioverter-defibrillator（ICD）was implanted for primary prevention. In July, while installing an outdoor air conditioning unit with bare hands on a rooftop, the patient experienced intermittent mild electric shocks to his fingers, followed by a sudden, intense electric jolt to his entire body. He fell approximately 50cm onto a lower level of the roof and was transported to our emergency department. Device interrogation revealed that high-frequency noise signals had been sensed as VF, triggering an inappropriate ICD shock. Although ICD therapy is a well-established, life-saving intervention for preventing sudden cardiac death due to malignant ventricular arrhythmias, it is occasionally vulnerable to electromagnetic interference（EMI） . Inappropriate ICD therapy due to EMI is not limited to medical settings ; it can also result from exposure to common electrical equipment encountered in daily life. Direct electric injury such as that caused by contact with improperly insulated devices can generate electrical noise signals that exceed the VF detection threshold, leading to inappropriate therapy. This case highlights the importance of patient education regarding potential EMI sources, including household and occupational electrical devices. Awareness of such risks may help prevent avoidable inappropriate ICD shocks and associated physical trauma.
