Pathologic features of surgically excised human umbilical vein grafts.

This article describes the pathologic changes in 31 human umbilical vein grafts excised from 23 patients after implantations ranging from 24 hours to 5 years. Gross morphologic examination, light microscopy, and scanning electron microscopy demonstrated that the umbilical vein grafts appeared to be fragile and easily delaminated. Bacteremic colonization on the luminal surface was present in the grafts removed because of infections but in two instances had extended into the wall. The presence of lipid on the surface and in the subintimal layer was observed in five grafts, three of which had been implanted for less than 1 month. We concluded that human umbilical vein grafts pathologically exhibit fragility, biodegradation, lipid accumulation, and bacterial colonization in infected cases, and these characteristics may adversely affect the durability and long-term success of the prosthesis.