An Uncommon Cause of Myopotentials Leading to Inappropriate ICD Therapy

Three patients underwent cardiac resynchronization therapy-implantable cardioverter defibrillator (CRT-D) implantation for standard indications. Each received a Guidant Contak-Renewal 3 device (IS-1 DF-1 41-J device; Guidant Corp., St. Paul, MN, USA) and the Guidant Endotak 0185 reliance integrated bipolar ICD lead (dual coil 64-cm active lead). At a routine check, the devices had logged multiple episodes of ventricular fibrillation (VF), most with diverted therapy.