The choice of operation in aortoiliac reconstructions for intermittent claudication

Multivariate Cox regression analysis of covariates for patency rates after femorodistal vein bypass grafting

Multivariate Cox regression analysis of patency rates for 750 consecutive femorodistal autogenous vein graftings for chronic lower limb ischemia showed that significant independent prognostic covariates were the type of graft (long saphenous or arm vein), presence of diabetes, and absence of a past history of myocardial ischemia. Analysis assumes that patients withdrawn with patent grafts due to death or loss to follow-up would have followed the same course as those who remain, and the degree to which this could distort results was studied. Patients who died with patent grafts were more likely to have had past myocardial ischemia and critical lower limb ischemia. Cox regression analysis for 600 operations after excluding patients who died with patent grafts then showed that significant independent covariates were the type of graft (long saphenous or arm vein) and indication (claudication or critical ischemia); then age, sex, hypertension, diabetes, myocardial ischemia, date of operation, surgeon, site of distal anastomosis, or first compared to repeat operations had no significant influence. Cox regression analysis helps determine which covariates influence graft patency rates, but results are affected by censored data, particularly from patients who die with patent grafts.

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.

Cumulative patency and actual palliation in patients with claudication after aortofemoral bypass. Prospective long-term follow-up of 100 patients

This report assesses patency, subsequent surgery, and the effect of late mortality in a series of 100 consecutive aortofemoral grafts performed for significant claudication on the basis of aortoiliac occlusive disease. Considering thrombosis or elective revision as failure, the primary patency rate at 5 and 10 years was 84 percent and 78 percent, respectively. However, most of these grafts were easily revised and remained patent for long periods, giving a secondary patency rate of 93 percent at 10 years. But survival is the critical factor in assessing what has really been accomplished for these patients. We believe that this is best expressed by cumulative actual palliation, that is, the patient alive, the graft patent, and the symptoms controlled without amputation. Cumulative actual palliation was approximately 75 percent at 5 years and 50 percent at 10 years. The palliation index (the proportion of living patients who were palliated) was more than 90 percent throughout the first 10 years. These data support the use of aortofemoral grafting in selected patients who suffer from intermittent claudication. Reporting the cumulative actual palliation, palliation index, and salvage index add precise and useful information to cumulative graft patency that disregards the effect of death.