[Laboratory assessment of haemostatic parameters in patients taking a direct thrombin inhibitor]

The problem of prevention and treatment of thromboembolic complications has a significant place in clinical practice for many years. The gold-standard agents in long-term protection from embologenic strokes, secondary prevention of venous thromboses and embolisms still remain vitamin K antagonists (in Russia - warfarin). However, despite high efficacy, administration of warfarin is fraught with dangers and associated with a series of inconveniences. A direct thrombin inhibitor, dabigatran etexilate (hereinafter referred to as dabigatran) was approved in the Russian Federation for prevention of thromboembolic complications in orthopaedic practice (2009), for prevention of ischaemic embologenic stroke in atrial fibrillation (2011) and for treatment of recurrent thrombosis of deep veins and pulmonary artery thromboembolism (2014). A characteristic feature of a therapeutic agent possessing an anticoagulation effect is correlation between intensity of hypocoagulation and haemorrhage. The effect of dabigatran on the laboratory parameters of haemostasis has been studied insufficiently, with no practical guidelines on assessing these alterations for prediction of the risk for haemorrhagic and thromboembolic complications. The present study included a total of 65 patients with non-valvular aetiology atrial fibrillation, taking dabigatran during from 6 to 18 months. All patients underwent laboratory assessment of the coagulation level and measuring blood coagulation activation markers in dynamics 10-14 days, 1, 6, 12 and 18 months after taking the agent. Thromboembolic and haemorrhagic risks were also assessed. It was revealed that administration of dabigatran leads to alterations in the main parameters of coagulogram. Determination of prothrombin (in % according to Quick's method) and activated partial thromboplastin time may be used for qualitative assessment of hypocoagulation. During the follow up period no statistically significant changes in the coagulation activation markers level were observed.