A device that is implantable in body tissue of a human or animal. The device is comprised of a header comprising at least one terminal adapted for removable connection to a lead and an open ended case closed by a plate to form a housing. The housing is comprised of a surrounding edge wall joined to a first side wall and a second side wall opposed to the first side wall. At least a first suture port extends through the edge wall and the second side wall but not the first side wall at an upper edge region of the housing. A second suture port may extend through the surrounding edge wall and the second side wall but not the first side wall in a similar manner. A third suture port may extend through the header. The three suture ports may define a triangular attachment configuration.