Synthetic aortic substitutes have given relatively satisfactory early results and consequently are being used with increasing frequency. Many factors concerning the ultimate fate of these materials are yet to be determined. There is evidence that the fabric itself loses strength following implantation in aortas of experimental animals.5 That aortic homografts fail to maintain their normal histologic configuration is now well established. Among the degenerative changes which have been observed are calcification, ulceration, loss of elastic tissue elements, and marked thinning of the wall.2,4
Observations over a two-year period of 17 dogs with nylon aortic substitutes were the subject of a previous report.1 A presentation of the histologic characteristics of this material follows.
Materials and Methods
Animals were killed at intervals from 1 to 760 days after implantation of the nylon tubes into the abdominal aorta. The "grafted" segment along with 2 to 4 cm. of adjacent aorta