Successful implantation of a subcutaneous cardiac defibrillator in a patient with a preexisting deep brain stimulator

Introduction In September 2012, the United Stated Food and Drug Administration approved the use of a fully subcutaneous implantable cardiac defibrillator (S-ICD, Boston Scientific Inc). The device is implanted in the left midaxillary space and attached to a single lead that is tunneled subcutaneously from the xyphoid process in 2 directions, superiorly to the sternal manubrium joint to the left of the sternum and laterally to the pulse generator. The lead consists of a single coil in the portion of lead along the sternum and 2 sensing electrodes, 1 at the tip of the lead at the upper portion of the sternum and 1 at the xyphoid process. Sensing is achieved via 1 of 3 potential configurations: between the device and the lower electrode, between the device and the upper electrode, or between the 3 electrodes. The sensing vector is automatically chosen by the device to minimize the chance of T-wave oversensing, but it can be manually overriden. A deep brain stimulator (DBS) is an electronic device consisting of a pulse generator and 1 or more electrodes implanted in the brain. It can be programmed to operate in a bipolar or unipolar stimulation mode. It is used for the treatment of Parkinson disease, among other neurologic conditions. Manufacturer’s recommendations for concomitant use of a transvenous implantable cardiac defibrillator (ICD) and DBS include setting the ICD to bipolar sensing. Sensing in an S-ICD is achieved via much wider bipoles than in a transvenous ICD, raising the concern of adverse interaction between the 2 devices. To our knowledge, we