[Thrombophilic states: their relevance in prevention and treatment of venous thromboembolism].

Thrombophilic states are congenital or acquired haemostasis disorders with pathophysiological and statistical association to increased risk of thrombosis. Venous thromboembolism is their most important clinical manifestation. More than 50% of patients with unprovoked thrombosis have one of the known thrombophilias. Patients with congenital thrombophilias have, in comparison to those without thrombophilia, increased risk of the first thromboembolic event, while the impact of genetically defined thrombophilic states on recurrence is less evident. The risk of recurrence in patients with idiopathic thrombosis is 7-10% per year even in the absence of a known thrombophilia. The risk of recurrent event is affected by a range of other factors (persisting or undiagnosed precipitating factor, proximal thrombosis and pulmonary embolism, incomplete recanalization, vessel thrombosis, presence of some thrombophilias, high D-dimmer levels after anticoagulant therapy discontinuation). Identification and subsequent monitoring of these factors is crucial for optimal selection of the treatment to be used as a secondary prevention of venous thromboembolism and its duration. Primary prevention of venous thromboembolism requires good knowledge of general precipitating factors as well as the specific risks in each patient and thus also means an early investigation of thrombophilic states in patients who will benefit from their identification and in whom there is at least medium probability of their identification. Universal long-term prevention in so far asymptomatic carriers of congenital thrombophilias is not indicated considering the potential complications of anticoagulant treatment. Women with thrombophilic disorders have an increased risk of thromboembolic event if using hormonal contraception and during pregnancy. They also have an increased risk of pregnancy complications related to placental circulation blood flow disorders.