A NEW EXPERIMENTAL-MODEL FOR SIMULTANEOUS EVALUATION OF AORTIC AND PULMONARY ALLOGRAFT PERFORMANCE IN A COMPOSITE GRAFT

A model was developed in pigs for simultaneous evaluation of aortic an d pulmonary allograft performance in a composite graft. The composite graft consisted of vascular prosthesis and aortic and pulmonary allogr afts. Following antibiotic preservation, it was anastomosed to the rec ipient's thoracic descending aorta by an extrapleural approach without using cardiopulmonary bypass. Aortic bloodflow was completely diverte d into the composite graft. All 12 recipient pigs recovered well, 4 of which were assigned for the initial study to design the suitable expe rimental schedule. Calcification readily occurred in the aortic allogr afts and aneurysmal dilatation without calcification developed in the pulmonary allografts. These morphological findings were consistent wit h those of previous reports. This model has several benefits. First, a ortic and pulmonary allograft conduits can be implanted and evaluated simultaneously under the same conditions by making a composite graft. Second the magnitude of the operation is minimum, and postoperative ci rculatory and respiratory management is uncomplicated. Third, wound in fection rarely occurs, because the skin incision is made on the back. These preliminary studies suggest that this model will allow future st udy concerning aortic and pulmonary allograft conduits under different conditions.