New technique for intrathoracic heart-lung transplantation in the rat.

A technique for intrathoracic heart-lung transplantation in the rat is described. The combined heart and left lung were transplanted into the recipient's thorax in place of the excised left lung. The graft's aorta was anastomosed end to side to the recipient's descending aorta. The bronchial anastomosis was made by the telescoping technique. When the aortic anastomosis was carried out, a total aortic clamp was used in group 1 (26 animals), and an internal shunt was used in group 2 (20 animals). One rat in group 1 and seven rats in group 2 survived with well-functioning grafts for more than 7 days after transplantation. This model of intrathoracic heart-lung transplantation appears to be suitable for investigations of rejection because the grafted lung is ventilated through the anastomosed bronchus. Our internal shunt method makes it possible for this system to be used as an experimental model.