F8 and COVID-19: Finally, the FVIII-von Willebrand Factor (vWF) complex is another prothrombotic unit responsible for the adhesion of platelets to subendothelial structures, released by endothelial cells when injured, in association with severe endothelial dysfunction; thus, it has been suggested as a biomarker of endothelial dysfunction, which is largely involved in COVID-19 pathogenesis [47,48,49,50,51,52].