Ambulatory pressure gradient in the veins of the lower extremity

Background: Neovascularization is an important cause of Venous reflux recur rence after high ligation of the long saphenous vein. The pathogenesis of t his phenomenon is so far obscure. It is possible that a hemodynamic factor - a pressure gradient between the femoral vein and the residual long saphen ous vein could be the trigger initiating the process of neovascularization. Patients and methods: Venous pressure measurements on eight patients with p rimary varicose veins were performed in the erect position in the insuffici ent long saphenous vein on the thigh. Mean pressures in the quiet standing position and ambulatory pressures were considered. By interrupting the saph enous reflux either distally or proximally to the point of measurement the pressure conditions either in the femoral or in the crural veins were simul ated. Results: With the tourniquet placed distally to the point of measurement, t he venous pressure in the upper interrupted segment of the long saphenous v ein (equivalent to the pressure in the femoral vein) remained uninfluenced during ambulation. In contrast by interrupting the reflux proximally to the point of measurement, a marked decrease of the ambulatory pressure in the lower part of the long saphenous vein (equivalent to the pressure in the cr ural veins) was noted. Conclusions: A pressure difference occurs between the veins of the thigh an d the lower leg during the activation of the the muscle venous pump. This f act may explain the tendency of recurrencies of varicose veins after high l igation of the long saphenous vein as well as the initiation of reflux.