Background: Deep venous thrombosis (DVT) leads to chronic venous insufficiency. Low molecular weight heparins (LMWH) are currently the medication of choice in DVT treatment, however, treatment with heparin does not restore the patency of the lumen of the vessel but merely prevents the progression of the thrombus in the distal and proximal directions. The aim of the study was an assessment (clinical and sonographic) of the long-term treatment results 2-10 years after heparin treatment of proximal DVT.
Material and methods: 60 patients with proximal DVT were enrolled into the study. The average period of the DVT symptoms duration before hospitalisation was 12.5 days. All patients were administered LMWH in therapeutic doses. Secondary prophylaxis included oral anticoagulant administration for a period of at least 6 months. A questionnaire with a quantitative score was prepared in order to compare symptoms and signs of deep venous thrombosis and chronic venous insufficiency before and at 2–10 years after heparin treatment. In all the patients, a clinical diagnosis of deep venous thrombosis was confirmed by an ultrasound examination which was repeated during the course of a remote clinical examination.
Results: Clinical examination: The total score for symptoms before heparin treatment was 172 and dropped to 171 during the follow up. The total score for signs before the treatment was 248 and dropped to 130 (p < 0.05) in the remote period following the treatment. In the US examination before the treatment the dilation of veins and positive compression test as well as oedema of the subcutaneous tissue was present in all the patients. The total occlusion of the deep vein system was recognized in 87.9% of the patients while partial occlusion with parietal flow canals was found in 12.1% of the cases. In the period of 2-10 years following the treatment, the US - Doppler revealed a partial recanalization or segmental occlusion in 45 patients (75%) while only 15 of the patients (25%) manifested complete restoration of vein patency in the segments affected by thrombosis. The presence of a blood reflux was found in 50 patients (83.3%).
Conclusions: According to the above-mentioned examination, due to the destruction of valves or venous wall, the majority of the patients with a history of proximal deep venous thrombosis treated with LMWH show an abnormal blood flow in venous vessels. The presence of a blood reflux in the Doppler US and oedema in the clinical examination are two most commonly recognized signs of a venous pathology in patients after proximal DVT treatment. It can be concluded that one of the factors related to these unfavourable results of the treatment is the delay in the DVT diagnosis leading to the further delay in administering anticoagulant treatment.