Perigraft-reaction after implantation of vascular prostheses. Pathogenesis, clinical picture and treatment.

This report is based on 18 perigraft reactions in 2237 implanted vascular prostheses (1970-1985). The incidence of this complication is 6.8-9.5/1000 both for Dacron-double-velour and expanded PTFE-prostheses. The clinical picture is characterized by localized or extended fluid accumulation around the artificial graft (perigraft cysts or "swimming prosthesis"). Including 271 reports from the literature, 75% of vascular prostheses in extraanatomical positions were affected. The time interval between vascular substitution and clinical manifestation is on average 23.5 months. The pathogenesis of this aseptic late complication is still unclear. Several disposing factors are under discussion: (a) physico-chemical irritation of the surrounding tissue by the fabric itself (release of monomers, emulgators etc.), (b) mechanical trauma (continuous movement of the graft in the tissue bed, i.e. insufficient tissue fixation resulting in gaps and exudation of fluid round the prosthesis), (c) latent or manifest renal insufficiency. The partial or total removal of the affected prosthesis and its substitution by another type of vascular prosthesis offers the best chance of definitive cure. Repeated puncture of perigraft cysts produces frequent recurrencies and the danger of secondary infections. Therefore only an exchange of the graft can be recommended.