Aim. To enhance the safety and efficacy of thermal ablation procedures in patients with chronic venous disease (CVD) of the lower limbs by developing a strategy for venous thromboembolism (VTE) prevention.

Materials and methods. This single-center, prospective, open-label study included 420 consecutive patients with CVD (C2–C6). Participants underwent radiofrequency ablation (RFA, n = 206) or endovenous laser ablation (EVLA, n = 214). At the first stage, VTE risk stratification was conducted using the Caprini scale; at the second stage, the optimal thromboprophylaxis algorithm was selected. Patients were divided into two homogeneous groups. Group 1 (208 patients) received VTE prevention with standard elastic compression only, while Group 2 (212 patients) received prophylaxis based on the proposed algorithm. The incidence of postoperative VTE and bleeding complications was assessed.

Results. According to VTE risk stratification, 23.6 % of patients were classified as low risk, 63.1 % as moderate risk, 9.0 % as high risk, 3.1 % as very high risk, and 1.2 % as the highest risk. Based on the second phase analysis, 12 patients (2.9 %) of Group 1 developed thrombotic complications during the early postoperative period: EHIT class II was diagnosed in 3 cases (0.7 %) after EVLA and in 2 cases (0.5 %) after RFA. Additionally, distal deep vein thrombosis (DVT) was detected in 7 patients (1.7 %) with high VTE risk on postoperative day 7: 3 after EVLA and 4 after RFA. Implementation of the proposed thromboprophylaxis strategy significantly reduced the total incidence of thrombotic complications compared to Group 1 (0.4 % vs. 2.9 %; p = 0.031). In Group 2, only one patient (0.4 %) with moderate VTE risk was diagnosed with distal DVT. Among 39 patients (18.3 %) who received prophylactic acetylsalicylic acid or rivaroxaban, a statistically significant increase in ecchymosis occurrence was observed (p = 0.018).

Conclusions. Implementing a differentiated, risk-oriented thromboprophylaxis strategy significantly (p = 0.031) reduced the incidence of VTE from 2.9 % to 0.4 %, p = 0.031, without increasing the risk of clinically significant bleeding.