Rethrombosis in COVID-19 patient

SARS-CoV-2 infection is associated with arterial and venous thrombotic complications. Autopsy findings revealed   microthrombi in multiple organ systems, that may contribute to multisystem organ dysfunction in severe COVID-19.Thrombosis in patients with COVID-19 is due to a cytokine storm, hypoxic injury, endothelial dysfunction and  increased platelet activity. Many difficult mechanisms contributes  formation clots in   vasculature of  multi organs , We presented two different cases of pulmonary artery thrombosis complicated by severe ARDS and rethrombosis in the branches of the pulmonary artery.Both  patient  was  treated  according  PE(pulmonary  embolism)  management  protocol (ESC) Conclusion: The  multisystem  mechanisms : The complement system , part of the innate immune response , capable of activating the coagulation cascade,  endothelial inflammation, loss of ACE2 and  alteration  of  PAI/tPA balance ,cytokine storm, high levels of the blood clotting protein factor, decreased concentrations of endogenous anticoagulant proteins   increasis  probability  of  new  thrombosis ,  despite  suitable treatment and  prevention