Undetected displacement of a subcutaneous implantable cardioverter-defibrillator lead

Background: In recent years, subcutaneous implantable cardioverter-defibrillator (S-ICD) implants have progressively increased and have been shown to be safe and highly successful, affording low reintervention rates regardless of the technique used. Case summary: We present a case of S-ICD implantation in a patient diagnosed with idiopathic ventricular fibrillation. In the first follow-up consultation the patient showed appropriate detection parameters in the three configurations. However, chest X-ray revealed lead displacement with a tip migration from the manubrium area of the sternum to the xiphoid process. Discussion: This case highlights the importance of performing at least one chest X-ray during the first weeks after S-ICD implantation, allowing the detection of a problem such as lead displacement, which can lead to undersensing of ventricular arrhythmias or S-ICD oversensing.