Title:COVID-19 and Thrombosis: Clinical Aspects
Volume: 23
Issue: 17
Author(s): Tetsumei Urano*, Atsushi Yasumoto, Kenji Yokoyama, Hisanori Horiuchi, Eriko Morishita and Yuko Suzuki
Affiliation:
- Department of Medical Physiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
- Shizuoka Graduate University of Public Health, Shizuoka, Japan
Keywords:
COVID-19, thrombosis, acute respiratory distress syndrome, low molecular weight heparin, myocarditis, vaccineinduced immune thrombotic thrombocytopenia.
Abstract: In coronavirus disease 2019 (COVID-19), thrombus formation is related to the pathogenesis
of acute respiratory distress syndrome (ARDS) and the progression of clinical symptoms. Severe
damage to vascular endothelial cells and the associated cytokine storm after SARS-CoV-2 infection
cause thrombogenesis and contribute to the development of more severe and unique thromboses
compared to other infectious diseases. Thromboses occur more often in critically ill patients.
In addition to pulmonary thromboembolism (PE) and deep vein thrombosis, acute myocardial infarction,
peripheral arterial thrombosis, and aortic thrombosis have also been reported. In PE,
thrombi develop in both pulmonary arteries and alveolar capillaries. These, together with intraalveolar
fibrin deposition, interfere with effective gaseous exchange in the lungs and exacerbate the
clinical symptoms of ARDS in patients with COVID-19. Pharmacological thromboprophylaxis is
recommended for all hospitalized patients to prevent both thrombosis and aggravation of ARDS,
and other organ failures. Although the pediatric population is mostly asymptomatic or develops
mild disease after SARS-CoV-2 infection, a new inflammatory disorder affecting the cardiovascular
system, multisystem inflammatory syndrome in children (MIS-C), has been reported. Similar to
Kawasaki disease, acute myocarditis, coronary vasculitis, and aneurysms are typically seen in MISC,
although these two are now considered distinct entities. A similar acute myocarditis is also observed
in young male adults, in which a hyperinflammatory state after SARS-CoV-2 infection
seems to be involved. Several side effects following vaccination against COVID-19 have been reported,
including vaccine-induced immune thrombotic thrombocytopenia and acute myocarditis.
Although these could be serious and life-threatening, the cases are very rare, thus, the benefits of
immunization still outweigh the risks.
