Critical ischemia of the lower limbs: A technique for repairing distal small sized arteries

Critical ischemia of the lower limbs This type of lesion, which spontaneous ly progresses to gangrene and amputation, is encountered more and more freq uently, Emergency endoluminal revascularization or bypass surgery is requir ed. When conventional endoluminal techniques cannot be used, a distal graft using the autologous saphenous vein is a promising alternative to achieve patent vascularization and salvage the limb. If venous material is not available Usable venous material is not always av ailable due to varicosities, thrombus formation, small size or previous sur gery (stripping, coronary surgery, prior revascularization procedure); rate s reported range from 20 to 40%. For such patients, other veins (external s aphenous, arm veins, superficial femoral veins) may be useful but are not a lways appropriate for distal repair. Different prostheses might also be use d but again do not always provide improved permeability. Most teams however use a polytetrafluoroethylene stent for revascularization of the distal le g. Different technical improvements favor success of prosthetic bypasses, b ut when used below the knee, flow remains less satisfactory than with venou s bypasses. Vein cuffs This procedure is a common adjuvant technique positioning a veno us cuff between the recipient artery and the prosthesis, The cuff avoids th e direct contact between the prosthesis and the fragile artery that is ofte n difficult to suture. Results Several series have demonstrated that the rate of success of vein c uff procedures remains lower than venous bypass procedures, but also that f low is better than with simple femorotibial prostheses. Pathogenic hypotheses The reduction of the neo-intimal hyperplasia observed in experimental models is insufficient to explain entirely the observed in vivo benefit. The fact that the suture is easier to make is one possible r eason. indeed the rate of failure of simple prosthetic bypass surgery is hi gh in the immediate postoperative period. These cases of thrombosis result from technical insufficiencies and are undoubtedly overcome by the use of t he venous cuff.