In this study the investigators will reprogram ICDs prior to surgery according to current practice, but will also record what would have happened had the ICD reprogramming not occurred ("detection on" but "therapy off"). In addition, the investigators will evaluate the effect of the location of the electrosurgery unit (ESU) return pad on the incidence of EMI. The investigators hypothesize that directing the current return path away from the ICD will result in lower EMI rates than previously described.