Predictive factors of a poor outcome following revascularization for critical limb ischemia: implications for practice.

Background: Advancements in open and endovascular techniques have brought a widespread indication of revascularization in the majority of patients with critical limb ischemia (CLI). However, some cases still have a dismal short-term outcome. Identifying preoperative variables that characterize these patients could be important to prevent futile decisions. The aim of this study was to define predictive risk factors of mortality and/or major amputation after revascularization for CLI.

Methods: Retrospective study of 515 consecutive patients (mean age=73 years; 73% males) undergoing open (N.=228; 44.3%) or endovascular (N.=287; 55.7%) surgery for CLI between 2005 and 2015. Neither redo-procedures (ipsilateral or contralateral) nor acute limb ischemia patients were included as new cases.

Results: Thirty-day amputation, mortality or combined event rates were 1.4% (N.=7), 4.5% (N.=23) and 5.6% (N.=29), while at 90 days were 4.1 (N.=21), 9.1% (N.=47) and 12.8% (N.=66), respectively. We found no significant differences between open or endovascular surgery. Risk factors associated with a 90-day combined event were age (OR=1.04, P=0.014), preoperative hemoglobin (OR=0.80; P=0.003), history of acute myocardial infarction (OR=2.68; P=0.007), ischemic ulcers (OR=2.57; P=0.014) and below-the-knee revascularization (OR=2.20; P=0.007). The discrimination of the model was good (area under ROC curve=0.75). Model predicted probabilities of the combined death and/or lower limb major amputation end-point ranged (95% interval) from 1.1% to 38.1%.

Conclusions: Certain preoperative variables can predict satisfactorily the short-term outcome after revascularization for CLI, although they are not sufficiently useful to identify the patient in whom revascularization can be clearly futile. Further research is needed to refine a predictive model suitable for decision-making.