Catheter and implantable leadless pacing devices, systems, and methods utilizing catheters and implantable leadless pacing devices are disclosed. An example catheter system may include a holding structure extending distally from a tubular member. An implantable device, such a leadless pacing device, may be located within a cavity of the holding structure and an electrical barrier may be located within the holding structure at a location between a proximal electrode and a distal electrode of the implantable device. The electrical barrier may inhibit electrical signals of the implantable device from traveling within the holding structure between the proximal electrode and the distal electrode of the implantable device. The holding structure may include one or more electrical ports adjacent the proximal end of the holding structure and adjacent or proximal of the proximal electrode of the implantable device.
