Recent Findings on Platelet Activation, vWF Multimers and Other Thrombotic Biomarkers Associated with Critical COVID-19

Mortality rate in patients with COVID-19 increases in those admitted to the ICU. Activation of the coagulation system is associated with the worse disease outcomes. The aim of this study was to evaluate platelet activation and thrombotic biomarkers in hospitalized patients with COVID-19 during the second and third infection waves of the pandemic during 2021, following a previous report that included patients from the first wave. Sixty five patients were recruited and classified according to disease outcome; 10 healthy donors were included as a control group. Among prothrombotic biomarkers, t-PA concentrations (p < .0001), PAI-1 (0.0032) and D dimer (p = .0011) were higher in patients who developed critical COVID-19. We also found platelet activation via αIIbβIII expression (p < .0001) and higher presence of vWF-HMWM in severe COVID-19 (p < .0001). Several prothrombotic biomarkers are found to be increased since hospital admission in patients which lately present a worse disease outcome (ICU admission/death), among these, platelet activation, vWF increased plasma concentration and presence of HMWM seem to be of special interest. New studies regarding the predictive value of thrombotic biomarkers are needed as SARS-CoV-2 variants continue to emerge.