Repair or replacement of descending thoracic aorta, without shunt or cardiopulmonary bypass, by open exposure, percutaneous or endovascular means, other than a service associated with a service to which item 11704, 11705, 11707, 11714, 18260, 33824, 38816, 38828 or 45503 applies (H) (Anaes.) (Assist.)