COVID-19 et pathologie thromboembolique veineuse

Coronavirus disease 2019 (COVID-19) is associated with an increased incidence of venous thromboembolism (VTE). Frequently asymptomatic, VTE has a negative impact on patients clinical course. On top of traditional VTE risk factors encountered during COVID-19 such as prolonged bed rest, hypoxemia and intravascular material, main features of patients with severe forms (old age, obesity) explain in part the VTE frequency. In addition, COVID-19 causes an endothelial disease following endotheliitis after the direct invasion of endothelial cells and a prothrombotic state secondary to the strong inflammatory response to infection. Altogether, these mechanisms lead to an extensive immunothrombosis within the pulmonary vasculature. VTE risk stratification to prescribe adequate anticoagulation is an imperious requirement in the COVID-19 treatment. So far, guidelines are mainly based on observational data. Randomized controlled clinical trials are ongoing and will allow to precise the anticoagulant regiment of patients hospitalized for COVID-19.