Fibrinogen and lipoproteins are considered to be the most decisive pacemakers in the pathogenesis of atherosclerosis. H.E.L.P. is based on the fact that lipoproteins as well as fibrinogen are precipitated at acid pH-values in the presence of heparin. Their elimination therefore leads to restoration of the micro-circulation, while the haemostasiological pattern remains unchanged. The increased oxygen supply to the tissue enables us to perform limb-saving surgical procedures instead of mutilating amputations: 16 patients with peripheral arterial disease in Fountaine's stages III and IV were submitted to 15 H.E.L.P. treatments each instead of primary limb amputation. Surgery was limited to the removal of gangrenous tissue only. None of the patients experienced any side-effects due to the procedure.