Combined use of a true-bipolar sensing implantable cardioverter defibrillator in a patient having a prior implantable spinal cord stimulator for intractable pain

Reported is a case involving a patient with a previously implanted spinal cord stimulator (SCS) who presented for an implantable cardioverter defibrillator (ICD), The SCS device was located in the left lower abdominal quadrant with a stimulation electrode array placed on the dorsal aspect of the spinal cord at the T-11 thoracic level. interaction testing demonstrated that the bipolar sensing transvenous ICD system (Medtronic 7221Cx PCD) did not detect the stimulator's output at burst rates ranging from 20-130 pulses/s, even with the ICD set to its maximum sensitivity of 0.15 m V and the stimulator programmed to the highest patient tolerated output combinations of 5 V, 0.45 ms in the bipolar configuration and 3 V, 0.45 ms in the unipolar (i.e., case-electrode) configuration.