Physiological vascular endothelium is an hemocompatible and thrombus resistant surface and none of the materials used for revascularisation owns these properties. The aim of this project is to improve the hemocompatibility of vascular prosthesis with a complete covering of their endoluminal surface with autologous endothelial cells. This strategy, that plans to associate an artificial component of synthetic origin and cellular component is a bioartificial vascular substitute concept. First results obtained by an austrian team are really encouraging (with more than 100 patients during last 10 years). Thus, the main objective of this study is to compare efficacy in terms of grafts with endothelialised PTFE prosthesis with great saphenous autologous vein graft for under knee arterial popliteal revascularisation of lower limbs.