Introduction: Severe ischemia occurring in the lower limbs represents the advanced stage of peripheral artery disease (PAD). Atherosclerosis and inflammatory markers have been intensively studied to identify prognostic tools with a role in the evolution of patients with PAD. The aim of this study is to demonstrate the predictive value of systemic inflammatory markers such as the neutrophil-to-lymphocyte ratio (NLR) and the systemic inflammation index (SII) in the prognosis of patients diagnosed with critical leg ischemia (CLI) undergoing infrainguinal surgical revascularization with remote endarterectomy. Materials and methods: This retrospective study included all patients admitted to the Vascular Surgery Clinic of the County Emergency Clinical Hospital of Târgu Mureș, Romania between January 2018 and December 2021, who had critical limb ischemia Leriche-Fontaine stage III and were treated with endarterectomy. Patients were divided into two groups based on the presence or absence of patency in the lower limbs at 12 months. Results: There was a higher baseline value of neutrophil count (p <0.0001), platelet count (p = 0.006), NLR and SII value (p <0.0001), as well as a lower value of lymphocyte count (p = 0.001) in the group without patency at 12 months. The ROC curve analysis showed that the NLR and SII were associated with the risk of major amputation and primary patency failure at 12 months, while multivariate analysis has shown that arterial hypertension (OR 3.63, p = 0.04), history of myocardial infarction (OR 2.93, p = 0.009), diabetes mellitus (OR 2.20; p = 0.04) and smoking (OR 3.48, p <0.0001) were also predictors of primary patency failure. Conclusions: The results of this study demonstrated the predictive role of NLR and SII regarding poor outcomes among patients with CLI Leriche-Fontaine stage III undergoing infrainguinal surgical revascularization with remote endarterectomy.