Is there a need for prolonged anticoagulation after COVID-19?

Anticoagulants after COVID-19 are indicated only for selected patients. But risks of venous thromboembolism (VTE) could be increased in a larger cohort of patients. <bold>Aim:</bold> – to investigate whether VTE after COVID-19-pneumonia depends on prophylactic anticoagulation during acute and post-acute COVID-19. <bold>Materials and methods:</bold> 43 pts (age – 60,0 (45,5; 65,0), men – 23 (53,5 %)) recovered from COVID-19 pneumonia were followed-up until 180,0 (120,0; 365,0) days from COVID-19 start. 12 pts had moderate COVID-19, 22 – severe and 9 – critical. They were divided in 3 groups: 1 – 9 pts who did not receive anticoagulation during neither acute nor post-acute COVID-19; 2 – 8 pts who received anticoagulation only during acute COVID-19 (enoxaparin 0,4 mg twice daily), 3 – 26 pts who received anticoagulation both in acute and post-acute COVID-19 (enoxaparin 0,4 mg twice daily and rivaroxaban 20 mg daily respectively). Log-rank tests was used. <bold>Results:</bold> Groups were comparable in age, sex and BMI, but not in COVID-19 severity. There were 4 (43,8 %) cases of VTE (pulmonary embolism) in group 1, 3 (33,3 %)– in group 2 and 0 – in group 3. VTE in group 1 happened on the 38, 55, 60 and 130 days from COVID-19 start; all of these pts had moderate course of COVID-19. VTE in group 2 happened on the 33, 40 and 45 days from COVID-19 onset which corresponded to the 16, 18 and 16 days after anticoagulation withdrawal. Two of these pts had severe course of COVID-19 and another one – moderate course of COVID-19 and inherited thrombophilia. Difference between groups according to Log-rank test was significant (p<0,01). <bold>Conclusion:</bold> Chanсes of VTE in post-acute COVID-19 is much less in case of prophylactic anticoagulation both in acute and post-acute COVID-19.