Intraoperative endothelial damage is associated with increased risk of stenoses in infrainguinal vein grafts

Objectives: saphenous vein injury is believed to predispose to vein graft s tenoses. The aims of this study were to assess the endothelial injury assoc iated with infrainguinal vein bypass surgery by serial measurements of seru m thrombomodulin concentration as well as by platelet scintigraphy, and to relate these findings with the postoperative development of stenoses. Methods: in 35 patients undergoing vein bypass surgery serum thrombomodulin concentration was measured pre- and postoperatively. Autologous 111-indium labelled platelets were administered into the common femoral artery immedi ately after restoration of flow in the graft and scintigraphic images were obtained 4 and/or 24 h later. Results: serum thrombomodulin increased markedly from median 17 ng/ml preop eratively to 32 ng/ml 1 day after surgery (p = 0.00002). Platelet scintigra phy revealed a total of 62 focal activity accumulations, the majority being located in the anastomotic regions. Among the 30 patients with grafts rema ining patent at 30 days stenoses occurred in nine (16%) of 55 regions with scintigraphic platelet accumulations as compared to only four (4%) of 94 re gions without platelet accumulations (p = 0.03). Conclusions: the very high predictive value of a negative platelet scintigr aphy (96%) strongly suggests that localised perioperative endothelial injur y is an important pathogenetic factor in the development of vein graft sten oses.