Use of a defibrillation coil in the coronary sinus to reduce ventricular defibrillation threshold

Although the majority of implantable cardioverter defibrillator (ICD) implants occur without complication, high defibrillation threshold (DFT) can occasionally be a problem. The usual resolution to this problem is to include a subcutaneous electrode in the defibrillation circuit. Use of the subcutaneous array, however, is unpopular as extensive subcutaneous dissection is time-consuming, uncomfortable for the patient and provides another focus for infection. We report the use of the coronary sinus for the placement of a second defibrillation shock coil in a patient with an unacceptably high DFT, which was successfully reduced.