The effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on ischemic stroke and the possible underlying mechanisms

Purpose: As of November 28, 2020, COVID-19 has been reported in 220 countries with 61,036,793 confirmed cases and 1,433,316 confirmed deaths; countries became vigilant around the world. In addition to SARS-CoV-2 causing pneumonia, many studies have reported ischemic stroke in patients with COVID-19. This article describes the effects and possible underlying mechanisms of SARS-CoV-2 on ischemic stroke. Materials and methods: A literature search was performed using PubMed, Web of Science, and other COVID-dedicated databases and the combination of the keywords 'SARS-CoV-2', 'COVID-19' and 'ischemic stroke' up to November 28, 2020. Results: SARS-CoV-2 invades the host through angiotensin converting enzyme 2 (ACE2). ACE2 is expressed not only in the lungs, but also in the brain and vascular endothelial cells. SARS-CoV-2 infection might cause direct vascular disease or enhance the immunogenic thrombosis environment through several mechanisms. SARS-CoV-2 infection can modulate the host immune response and can cause inflammation, coagulation disorders, renin angiotensin system disorders, hypoxia, and stress disorders, which may lead to the occurrence of ischemic stroke. Conclusions: Some patients with COVID-19 can develop ischemic stroke. Ischemic stroke has a high risk of causing disability and is associated with a high mortality rate. It is hoped that when medical staff treat patients with COVID-19, they would pay attention to the occurrence of ischemic stroke to improve the prognosis of patients with COVID-19.