An unusual cause of inappropriate shocks delivered by an implantable cardioverter defibrillator

Introduction: Cardiac implantable electronic device (CIED) complications present significant challenges in clinical practice, especially in elderly patients with multiple comorbidities. Common adverse events include infection, lead malfunction, and device migration. Twiddler's Syndrome, a rare but serious CIED complication characterised by patient manipulation causing lead displacement and device malfunction, is often underreported. The literature consists mainly of case reports and small series, providing limited guidance on prevention and management. As CIEDs are critical for managing cardiac arrhythmias and heart failure, understanding and addressing Twiddler's Syndrome is essential. This case report aims to contribute to the literature by detailing a case of Twiddler's Syndrome, emphasising the importance of a multidisciplinary approach for optimal management.

Case presentation: A 59-year-old male presented with discomfort around his implantable cardioverter defibrillator (ICD) site and the sternal area over the past two days. He denied pain, dyspnoea, or dizziness. Clinical examination revealed a normal heart rhythm and no peripheral pulse deficit. Ultrasound revealed a reduced left ventricular ejection fraction. The atrial lead was not visible, and the shock coil was misplaced. ICD interrogation showed inappropriate shocks due to sensing artifacts and exit block in both leads, with no arrhythmias detected. An X-ray confirmed lead dislodgement and significant entanglement in the pocket. The patient was diagnosed with Twiddler's Syndrome and scheduled for surgical revision.

Discussion/conclusions: Dilated cardiomyopathy (DCM), characterised by left ventricular dilatation and dysfunction, accounts for a significant proportion of systolic heart failure cases. Despite advancements in heart failure management, DCM patients remain at high risk for sudden cardiac death (SCD), making ICD implantation crucial. However, CIED placement carries risks of complications, including Twiddler's Syndrome. This condition can lead to lead dislodgement and device malfunction, resulting in inappropriate shocks and potential patient harm. In this case, a single-session extraction and re-implantation were successfully performed using a multidisciplinary approach, emphasising the importance of comprehensive management strategies to address such complications effectively. Regular follow-up showed no adverse events, highlighting the procedure's success and the potential benefits of using advanced antimicrobial adjuncts to prevent infections. This case underscores the need for awareness and standardised protocols for managing Twiddler's Syndrome to improve patient outcomes in the growing population of CIED recipients.