Predictors of Limb Loss Despite a Patent Endovascular-Treated Arterial Segment (PETAS)

Objective: The goal of this study was to assess the frequency and predictors of major amputation with patent endovascular-treated arterial segments(PETAS) in patients with tissue loss.
Methods: Consecutive patients(n=415) who underwent EV(n=236) or OPEN(n=179) revascularizations for tissue loss between 6/2001-5/2007 were included. Patients with limb loss(LL) despite PETAS were compared to the rest of the endovascular-treated group(EV-OTHER,n=212),and to those who underwent amputations with patent bypasses(APB).
Results: Twenty-nine amputations were performed in EV(24-PETAS,5 in EV-OTHER), and 40 in OPEN(17-APB,23 in OPEN-OTHER). Amputations occurring despite patent revascularized segment constituted 43% of LL in OPEN and 83% in EV-treated patients(P=0.001). LL occurred earlier in PETAS group(58%vs29% within 3 months). Primary indications for LL were extensive tissue loss after radical debridement of infection/gangrene(37%), recurrent infection(42%), and failure to reverse ischemia(21%). There was no difference between groups except for diabetes(PETAS-92% vs APB-47%,P=0.019). Diabetes, dialysis-dependence, lower albumin level, gangrene and infrapopliteal interventions were more likely in PETAS than EV-OTHER group(Table). Twelve-month survival in PETAS was worse than both APB or EV-OTHER(64±10%vs88±8%,P=0.021 and 78±3%,P=0.07). Multivariate analysis showed diabetes(OR:2.8,95%CI:1.1-6.7,P=0.025), gangrene(OR:3.7,95%CI:1.6-8.6,P=0.002), and having infrapopliteal interventions(OR:2.7,95%CI:1.3-5.8,P=0.01), predicted LL with patent open or endovascular-treated segments whereas dialysis-dependence(P=0.202), peroneal artery-only runoff(P=0.495), albumin level(P=0.279), and type of treatment(P=0.499) did not.
Conclusions: Amputation despite PETAS is the most common means of LL in patients undergoing endovascular revascularization for limb salvage, and occurs mostly in the first 3 months following intervention. Patients with diabetes and gangrene, or infrapopliteal interventions, are at significantly higher risk. Adjuncts to reduce tissue loss, and prevention of recurrent infection are needed to prevent LL despite PETAS, especially in diabetic patients.