Inappropriate implantable defibrillator discharges from lead failure

To the Editor: A 77-year-old woman with a history of idiopathic long-QT syndrome (presumed genetic) presented to hospital with a storm of defibrillator shocks from her implantable cardioverter defibrillator (ICD). She had a single-chamber Guidant Ventak Prizm VR, model 1850, and a Guidant ventricular lead, model 0148 (Guidant Corporation, Indianapolis, Ind, USA) implanted 12 months earlier after an episode of syncope. The lead had been implanted by left subclavian venous access. The patient’s postoperative course and responses to routine questioning indicated that the device was functioning normally.