Patient, 57 years old, presented with pain and dry gangrene at the first finger of the left foot due to arteriopathy. This caused the decrease level of the blood to the foots, followed by ischemia and necrosis. The patient also presented oedema at both foots, treated with diuretics. He has smoked 2 cigarette packs every day, in the last 20 years. What is your treatement in this case?