Follow-up X rays play a key role in detecting implantable cardioverter defibrillator lead fracture: a case of incessant inappropriate shocks due to lead fracture.

A patient with an implantable cardioverter defibrillator (ICD) received incessant inappropriate shocks due to a lead fracture 3 years after implantation. Routine lead measurements at 3-month intervals had shown no abnormal findings even at the most recent measurement performed 2 months prior to the event. In contrast, serial observation of chest X rays clearly disclosed progressive lead narrowing starting 11 months prior to the event. This case indicates the importance of the routine chest X rays in long-term follow-up of ICDs and sets a precedent for interpreting lead narrowing in such X rays.