Endothelial activation. Glycocalyx shedding yields soluble thrombomodulin (sTM) and von Willebrand factor (vWF); endothelial extracellular vesicles (ICAM-1+) and miRNAs (miR-126-3p, miR-210) correlate with IMT progression and FMD decline, and portend mortality in severe COVID-19, underscoring a shared redox–endothelial axis (172, 173). Here, VWF is linked to COVID-19.