INFLUENCE OF ANGIOSCOPIC VEIN GRAFT PREPARATION ON DEVELOPMENT OF NEOINTIMAL HYPERPLASIA IN AN ORGAN-CULTURE MODEL OF HUMAN SAPHENOUS-VEIN

Purpose: Angioscopy for in situ vein graft preparation has been critic ized on the basis that the trauma of instrumentation may predispose to accelerated intimal hyperplasia, jeopardizing patency rates following infrainguinal revascularization. The aim of this study was to assess the effects of angioscopic preparation on endothelial integrity and sm ooth muscle cell (SMC) behavior in an established organ culture model of human saphenous vein (HSV). Methods: HSV was harvested from 12 pati ents during bypass surgery before and after angioscopic preparation. E ndothelial integrity was evaluated by immunohistochemical staining wit h JC-70 and scanning electron microscopy (SEM); remaining segments of pre-and postangioscopy vein were maintained in culture for 14 days in medium supplemented with 30% fetal calf serum. Viability was confirmed by measurement of tissue adenosine triphosphate on day 14 and thickne ss of the neointima was measured by computerized image analysis of his tologic sections. Monoclonal antibodies to proliferating cell nuclear antigen (PCNA) were used as an immunohistochemical marker for prolifer ating SMCs. Results: There was a significant reduction in the percenta ge staining by JC-70 (71.3% versus 20.4%) in pre- versus postangioscop y vein (p = 0.002 by Wilcoxon's rank test; n = 12). This was supported by SEM images. Despite this, there were no significant differences be tween the pre- and postangioscopy HSVs after 14 days of culture with r espect to neointimal thickness (61 versus 56 mu m) and staining with P CNA (4.80 versus 4.08 nuclei per 10 mu m), all according to Wilcoxon's rank test. Conclusions: Angioscopic vein graft preparation is associa ted with endothelial cell loss but does not induce additional neointim al hyperplasia in HSV in vitro. These results suggest that angioscopic manipulation does not alter SMC behavior.