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[Peculiarities of hemostasis in patients with COVID-19]
A I Kalinskaya1,2, O A Dukhin1,2, I A Molodtsov1
1Davydovsky City Clinical Hospital.
Insights
COVID-19 infection alters clot formation, increasing clot growth and size, particularly in severe cases. Secondary platelet activation correlates with disease severity, suggesting localized endothelial dysfunction.
Area of Science:
- Cardiovascular Medicine
- Hematology
- Infectious Diseases
Context:
- COVID-19 is associated with significant thrombotic complications.
- Understanding the hemostatic changes in COVID-19 is crucial for patient management.
Purpose:
- To analyze clot formation and lysis dynamics in COVID-19 patients across different disease severities.
- To compare hemostatic parameters between COVID-19 patients and healthy controls.
Summary:
- COVID-19 patients exhibited reduced platelet aggregation and increased clot growth rate, size, and density compared to controls.
- Severe COVID-19 cases showed higher clot growth and size, with increased platelet aggregation and elevated von Willebrand factor antigen levels.
- Endothelial function, assessed by flow-mediated dilation, did not differ significantly between patient subgroups, suggesting localized dysfunction.
Impact:
- Findings indicate that plasma hemostasis and secondary platelet activation are key factors correlating with COVID-19 severity.
- The study highlights predominantly local endothelial dysfunction in moderate to severe COVID-19, informing therapeutic strategies.
Aim:
Analysis of the dynamics of different stages of clot formation and its lysis in patients with different COVID-19 severity.
Materials And Methods:
We prospectively included 58 patients with COVID-19 (39 patients with moderate disease severity and 18 patients with severe disease) and 47 healthy volunteers as a control group. All participants underwent the assessment of flow-mediated dilation (FMD) of brachial artery, impedance aggregometry, rotational thromboelastometry and thrombodynamics. Von Willebrand factor antigen (vWF:Ag) quantification was also performed in patients with COVID-19. Measurements were repeated on the 3rd and 9th day of hospitalization.
Results:
Compared to the control group, patients with COVID-19 showed reduced values of platelet aggregation and greater values of the clot growth rate, as well as its size and density. On the first day of hospitalization, we found no differences in the activity of plasma hemostasis and endogenous fibrinolysis between subgroups of patients. With the progression of the disease, the growth rate and size of the clot were higher in the severe subgroup, even despite higher doses of anticoagulants in this subgroup. An increase in platelet aggregation was noted during the progression of the disease, especially in the severe subgroup. There were no differences in the results of the FMD test by subgroups of patients. The vWF:Ag level was significantly higher in the severe subgroup.
Conclusion:
Thus, plasma hemostasis followed by secondary platelet activation correlates with the severity of COVID-19. Patients with moderate to severe coronavirus infection have predominantly local rather than generalized endothelial dysfunction.
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