Extraperitoneal unilateral iliac artery bypass for chronic lower limb ischaemia.

Extraperitoneal unilateral iliac artery bypass was used to treat chronic lower limb ischaemia in 105 patients (110 operations). This represented 20% of all operations for aorto-iliac disease. Unilateral iliac bypass was the preferred primary procedure for 99 operations, and was used to correct complications in one limb of a prior aortic bifurcation graft in the other 11. Ipsilateral femoropopliteal vein grafts were also performed in 45 legs (43%), prior to the iliac bypass in 18, as a synchronous operation in nine, and at a later date in 18 legs. This was a much higher proportion of combined operations than for patients by aortic bifurcation grafts (12%). Only 5 patients later required further proximal surgery, one for a blocked graft and four for contralateral iliac disease. The cumulative patency rate in surviving patients was 91% at 3 years. For the claudicants and for iliofemoral bypass operations, only one graft occluded, within 5 years, and no grafts occluded for operations where the superficial femoral artery was patent. The cumulative patency rates at 3 years were 85% for patients with critical ischaemia, 82% for ilioprofunda bypass operations, and 88% for operations where the superficial femoral artery was occluded. The cumulative foot-salvage rate in surviving patients initially treated for critical ischaemia was 77% at 3 years. The cumulative survival rate was 90% at 3 years. Extraperitoneal unilateral iliac bypass is now preferred as the primary operation for patients with apparent unilateral iliac disease causing severe ischaemia, if balloon dilatation is not appropriate or has failed.