RESUMEN
BACKGROUND: We wanted to know the effect of comorbidity, age, and gender on the outcome after surgical below-knee revascularization for critical chronic limb ischemia. METHODS: This is a retrospective study of 624 consecutive patients who underwent below-knee bypass surgery between January 1996 and December 2005 because of chronic peripheral arterial disease (PAD). Patients' characteristics were: diabetes mellitus (DM) n = 445 (71%), coronary artery disease (CAD) n = 310 (49%), dialysis-dependent renal insufficiency (dRI) n = 88 (14%), age >70 years n = 279 (44%), male n = 423 (68%), PAD Fontaine's stage III n = 105 (17%), and PAD stage 4 n =519 (83%). All patients had Trans Atlantic Inter-Society Consensus (TASC) C and D lesions, all were treated with a vein bypass to a crural artery n = 354 (57%) and to a pedal artery n = 270 (43%). Kaplan-Meier analysis and multivariate analysis were performed. RESULTS: The early results were as follows. The 30-day major amputation rate was n = 43 (7%). CAD, dRI, age, and gender did not influence major amputation rate, whereas patients with diabetes had a lower risk of early amputation than those without diabetes. (hazard ratio: 0.49, 95% confidence interval: 0.25-0.95, p < 0.05). The 30-day mortality rate was n = 31 (5%) and was uninfluenced by DM, CAD, and gender. Patients with dRI and octogenarians had a high risk of early death (dRI: 13.6%, octogenarians 9.4%). The late results were as follows. Follow-up rates were: limb salvage n = 596 (95.5%) and survival n = 622 (99.7%). The limb salvage rates at 1, 3, and 5 years were 79.1%, 72.1%, and 66.4%, respectively, and were uninfluenced by DM, CAD, dRI, age, and gender. The mortality rates at 1-, 3-, and 5-years were 79%, 63.4%, and 47.3%, respectively. Comorbidities such as CAD, dRI, and age of >70 years reduced life expectancy significantly. DM did not influence 1, 3 and 5 years of survival. The 5-year survival rates as estimated by Kaplan-Meier analysis after revascularization were: DM, 46%; CAD, 38%; dRI, 19%; and age >70 years, 37%. CONCLUSION: Advanced age and comorbidities reduce life span but not the chance of avoiding major amputation after below-knee bypass surgery for critical limb ischemia.