Popis: |
Conventional bypass surgery is only possible when patent distal arterial outflow vessels are available. In patients with critical limb ischemia and occluded distal arteries, attempts have been made to establish retrograde perfusion through either deep or superficial pedal veins. Though historical results were disappointing, more recently limb salvage has been achieved after adopting a principle of 1) placing the anastomosis distally, and 2) actively destroying the distal valves. Experimental, para-clinical, and clinical data confirm that direct tissue nutrition is improved, angiogenesis stimulated, and collaterals opened. Only a limited number of cases have been reported in the literature and a number of different operative techniques have been described. The results in terms of limb salvage and wound healing vary widely. Generally, results are poorer than what would have been expected if femoro-distal arterial bypass had been possible. Recently, hybrid approaches have been developed to avoid extensive distal incisions by endovascular destruction of valves and closure of side branches. Also, a totally endovascular technique, including the position of a stent graft between the vein and artery, has been proposed and tested. These developments may in the future improve results by limiting incisional wound complications and make this treatment available to more patients who would otherwise have no other alternative than amputation. |