Aim. To analyze features of lesion and the results of femoropopliteal (tibial) bypass in situ for acute arterial insufficiency and critical ischemia. Material and methods. The study included 12 patients with postembolic occlusion of lower extremities arteries. In-hospital and 1-year incidence of complications and correlation of risk of graft thrombosis with various factors were determined.Results. Prolonged lesion type D is characteristic for postembolic occlusion of lower extremities arteries (75%). One- and two-year survival was 100% and 75.0% respectively. Graft thrombosis was observed only in 8.3% of cases after bypass in situ followed by development of critical lower limb ischemia and need for reoperation. We have also obtained significant direct correlation of graft thrombosis in 1 year after surgery with such factors as diabetes, lower limb ischemia IV degree, TASC II type D of peripheral arteries disease and inverse correlation with age. The probability of graft thrombosis during 1 year after surgery can be determined using predictive model developed by us with sensitivity 80% and specificity 86%.