Potential predictors of outcome in patients with tissue loss who undergo infrainguinal vein bypass grafting

Purpose: Aggressive attempts at limb salvage in patients with ischemic tiss ue loss are justified by favorable initial results in most patients. The id entification of patients whose conditions will not benefit from attempted r evascularization remains difficult. Methods: This study was designed as a retrospective review of prospectively collected clinical data. The subjects were 210 consecutive patients who un derwent infrainguinal vein bypass grafting for ischemic tissue loss in the setting of an academic medical center. Bypass grafting was to the popliteal artery in 56 patients, to the infrapopliteal arteries in 131 patients, and to the pedal arteries in 23 patients. The follow-up examination was comple te in 209 of 210 patients. One hundred twenty-five patients underwent blind ed review of duplex scan venous mapping and arteriography to determine simp lified vein and run-off scores. The outcome measures were the influence of risk factors, venous conduit, and runoff on mortality, limb loss, and graft failure at the 6-month follow-up examination. Results: One hundred seventy patients (81%) were alive and had limb salvage . Nineteen patients (9.1%) died, with need for a simultaneous inflow proced ure and end-stage renal disease being most commonly associated with mortali ty. Thirty-three patients (15.8%) had undergone amputation: 18 after graft failure, and 15 for progressive tissue loss despite a patent graft. Amputat ion was significantly more common in patients with diabetes (P =.05) and wi th poor runoff scores (poor runoff, 44.4% vs good runoff, 7.4%; P <.01). Am putation despite a patent graft also correlated with runoff (poor runoff, 4 1.7% vs good runoff; 4.3%; P <.01). Twenty-five patients had graft failure without amputation, so that only 145 patients (69.4%) were alive, had limb salvage, and had a patent graft. Run-off score was the strongest predictor of outcome, with 70% of patients with poor run-off scores having death, amp utation, or graft failure. Conclusion: Aggressive use of infrainguinal vein bypass grafting in patient s with ischemic tissue loss results in a high rate of initial limb salvage but significant morbidity and mortality. Arteriographically determined runo ff scores appear to potentially identify patients at high risk for a poor i nitial outcome and may provide a method of selecting patients for primary a mputation.