[Treatment of the post-thrombotic syndrome: modification of May's femoral by-pass (author's transl)].

During May's femoral by-pass, one should avoid by sapheno-popliteal anastomosis, obstruction of the femoral vein damaged by the post-thrombotic syndrome. After the early work of Kunlin, arterio-venous fistulas are often found in reconstructive venous surgery. By making a transverse end-to-side anastomosis between the main peripheral saphenous vein and the posterior tibial artery behind the internal malleolus, one may obtain a protective effect on the sapheno-popliteal anastomosis, increasing the blood flow towards the main saphenous vein across the perforating veins down to the deep leg veins. The protective effect of the arterio-venous fistula seems to be of interest during inactivity of the muscular pump of the calf (postoperative phase and during rest at night).