Evaluation of the deep vein recanalisation and function after low molecular weight heparin (calcium nadroparine) therapy of deep vein thrombosis. Preliminary report

Introduction. The standard treatment for acute episode of deep vein thrombosis (DVT) included at least five days administration of unfractionated heparin followed by oral anticoagulants (OAs) in the subsequent months. In the early 2000s the use of low-molecular-weight heparins (LMWH) was recommended and validated as the equivalent for the standard therapy of acute episode of DVT. The aim of this study was to evaluate the patency of thrombotic venous segments and indirectly the function of valves after therapy with calcium nadroparine in the 10 days ambulatory treatment and three-month secondary prophylaxis of acute DVT. Material and methods. The study group consisted of 50 patients (10 females and 40 males), aged 33 to 92 years (mean age 62.3 years) with first episode of acute, symptomatic deep vein thrombosis of the lower extremities, below the inguinal ligament, who were followed-up during their 10 days ambulatory treatment and three-month secondary prophylaxis with calcium nadroparine. Each patient had clinical examinations and ultrasound of the veins of the lower extremities, using the colour-coded power Doppler ultrasound (CDU) performed by the same experienced physician, using TOSHIBA device (linear probe 6-12 MHz), on day 1 and 10 of the treatment period and after 1 and 3 months of secondary prophylaxis phase. All patients underwent the following laboratory tests: before treatment the coagulation profile, blood group and complete blood count; the control platelet count was performed after 7 to 10 days of LMWH treatment, and then every 10 days. Results. The thrombosis was revealed in the femoro-popliteal segment in 35 (70%) subjects and below the knee in the remaining 15 (30%) patients. There was no case of DVT recurrence, thromboembolic event or death in patients who received LMWH therapy during the 3-month follow-up period. No adverse effects of the treatment were observed. CDU revealed the complete venous recanalisation in 40 (80%) patients and partial recanalisation with residual thrombi and/or wall thickening in the remaining 10 (20%) subjects. After the 3-month treatment period deep vein reflux was not observed in 30 (60%) patients, whereas the remaining 20 (40%) were diagnosed with only an insignificant reflux (lasting 1-2 seconds). Conclusions. The calcium nadroparine therapy is an efficient, safe and well tolerated method of ambulatory treatment and secondary prophylaxis of the acute, symptomatic deep vein thrombosis of the lower extremities. Further, longer and prospective, multi-centre studies are required for better evaluation of the early and late results of DVT treatment with LMWH. They would allow investigating their effect on venous recanalisation, its function and prevention of post-thrombotic syndrome.