Perigraft seromas complicating arterial grafts.

A collection of clear, sterile fluid, confined within a nonsecretory fibrous pseudomembrane surrounding a vascular graft, is a specific clinicopathologic entity termed perigraft seroma. Our experience with four such cases prompted a clinical study of our own material and that of others. A comprehensive survey, including the entire North American Chapter of the International Society for Cardiovascular Surgery membership, provided 279 cases for detailed analysis. Material most commonly involved were knitted Dacron (54%) and polytetrafluorethylene (34%), with knitted Dacron in the axillofemoral position accounting for 31% of the cases. The fluid was documented as serum by biochemical and electrophoretic analysis. Histopathologically, the grafts were noted to be poorly incorporated into the surrounding tissues, and the graft lining was covered by a flimsy, fibrous layer with a degenerated fibrin-protein matrix noted in the interstices of the graft. These findings pertained to both polytetrafluoroethylene and Dacron; neither acute nor chronic inflammatory changes were noted. The cyst membrane was comprised of nonsecretory cells, primarily fibroblasts. Treatment was highly variable. Graft replacement provided a 92% cure rate, and the authors advocate removal of the original graft and cyst membrane with placement of a new graft of material other than the original along a different anatomic route. However, in elderly, poor-risk patients, resolution may occasionally be achieved by "watchful waiting" with or without multiple aspirations.