Pulmonary embolism in patients in acute COVID-19, long-COVID and post-COVID syndrome.

COVID-19 is a disease caused by the SARS-CoV-2 virus, which, after entering a living organism, uses the ACE-2 protein as a receptor and several other proteins as cofactors of infection. Disease symptomatology is extensive, involving mostly predominant respiratory symptoms, as well as those of the nervous, gastrointestinal, circulatory and other systems. Incidence of COVID-19 also results in markedly different laboratory findings on the hemostatic system with the predominant feature of increased D-dimer levels. In the pathogenesis of thromboembolic complications in COVID-19, all elements of Virchow's triad are involved: endothelial damage, coagulation disorders and blood flow disorders. Coagulopathy increases with the severity of the clinical course of COVID-19. One of the causes of mortality associated with COVID-19 is pulmonary embolism. SARS-CoV-2 infection increases the risk of thromboembolic complications not only in the acute period of the disease. Also in the period of about a month after recovery, there is an increased risk of venous thrombosis and consequently, life-threatening pulmonary embolism. The classic biomarker of pulmonary embolism in the general population is D-dimers. Among imaging studies, the gold standard for diagnosing this disease is computed tomography of the pulmonary arteries (CTPA). Other useful diagnostic tests are ventilation-perfusion lung scintigraphy (VQ Scans) or echocardiography. Currently reviewed guidelines and recommendations recommend extens ive thromboprophylaxis in COVID-19 patients in both acute and chronic phases of the disease. Keywords: COVID-19, pulmonary embolism, laboratory and imaging diagnostics, thromboprophylaxis.