Where is the Lead? Inappropriate Implantable Cardioverter-Defibrillator Shock Caused by Extreme Twiddling

Abstract

A 43-year-old man who had received mitral and aortic valve replacement surgery underwent the implantation of an implantable cardioverter defibrillator (ICD) for sustained ventricular tachycardia. The patient presented with a sudden jolting sensation in his left upper chest area one year after the device implantation. He had a history of vigorous upper body exercise during the several months of the follow-up period. Device interrogation revealed complete sensing and capture failure. The ventricular lead impedance was in the normal range, but the high voltage impedance had dropped to less than 10 Ω. Four inappropriate shocks for ventricular fibrillation had been delivered due to over-sensing of the atrial signal on the ventricular lead. Chest radiography showed ventricular lead displacement with extreme rotation and flipping-over of the generator. In the lead revision operation, the old ventricular lead was extracted and replaced, and the generator was fixed more deeply in the pocket with a non-absorbable ligature.