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COVID-19 hemodynamic and thrombotic effect on the eye microcirculation after hospitalization: A quantitative

Aristotle G Koutsiaris1, Konstantina Riri2, Stylianos Boutlas3

  • 1Medical Informatics Laboratory, Faculty of Medicine, School of Health Sciences, University of Thessaly, Biopolis, Larissa, Greece.

Clinical Hemorheology and Microcirculation
|August 1, 2022
PubMed

Insights

COVID-19 survivors show significantly reduced eye blood flow and increased microthrombosis, even with preventative treatment. This may explain long COVID symptoms and suggest new coagulation factors.

Area of Science:

  • Ophthalmology
  • Vascular Biology
  • Infectious Diseases

Background:

  • COVID-19 can affect microcirculation, leading to potential long-term complications.
  • Understanding these effects is crucial for managing post-hospitalization recovery.

Purpose of the Study:

  • To quantify the hemodynamic and thrombotic impact of COVID-19 on ocular microcirculation.
  • To assess these effects in patients receiving thromboprophylaxis after hospital discharge.

Main Methods:

  • A case-control study comparing 17 COVID-19 survivors with 17 healthy controls.
  • Conjunctival Video Capillaroscopy (CVC) used to measure axial blood velocity (Vax) and percentage of occluded vessels (POV).
  • Microvessels analyzed included capillaries (CAP), postcapillary venules size 1 (PC1), and size 2 (PC2).

Main Results:

  • COVID-19 survivors exhibited significantly reduced Vax (39-47%) across all analyzed microvessel types compared to controls.
  • A substantial increase in POV (600%) was observed in COVID-19 survivors.
  • Demographics between the COVID-19 and control groups were comparable.

Conclusions:

  • COVID-19 significantly impairs ocular microvascular blood flow and promotes microthrombosis, even with thromboprophylaxis.
  • These findings offer a potential explanation for persistent symptoms in long COVID.
  • The results suggest the possible involvement of an unidentified coagulation factor in COVID-19's vascular effects.
Abstract

Keywords:
COVID-19blood velocityconjunctival video capillaroscopyeyemicrocirculationmicrothrombosisoccluded microvesselsthromboprophylaxis

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