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.

Neurological manifestations in COVID-19 and its possible mechanism.

In December 2019, the first cases of the acute respiratory illness now known as Corona Virus Disease 2019 (COVID-19) occurred in Wuhan, Hubei Province, China. The main clinical manifestations of COVID-19 are a fever, dry cough and general weakness, although in some patients, a headache, tight chest, diarrhea, etc. are the first clinical manifestations. Neurological practice is involved in all aspects of medicine, from primary care for patients with migraines to consultations with patients in the intensive care unit. Few disorders spare the nervous system, and newly emerging infections are no exception. As neurologists, we are concerned about the effects of SARS-CoV-2 infections on the nervous system. Multiple neuropathy, rhabdomyolysis, cerebrovascular disease, central nervous system infections and other common neurological diseases require attention during this outbreak.

Potential mechanisms of hemorrhagic stroke in elderly COVID-19 patients.

The novel severe acute respiratory syndrome coronavirus 2 is the causative agent of coronavirus disease 2019, a new human infectious disease. While fever, cough, and respiratory distress are typical first symptoms, a fraction of those affected present instead with neurological symptoms suggestive of central nervous system compromise. This review summarizes the potential contribution of coronavirus disease 2019 to hemorrhagic stroke in the elderly and proposes possible mechanisms. Reports show that the most affected patients have underlying chronic diseases such as hypertension and diabetes, which are two key risk factors for hemorrhagic stroke. Angiotensin-converting enzyme 2 is the main host cell surface receptor interacting with the severe acute respiratory syndrome coronavirus 2 spike glycoprotein to allow viral entry and infection. We speculate that ensuing downregulation of angiotensin-converting enzyme 2 expression may compound the risk conferred by pre-existing comorbidities and critically influence the pathogenesis of hemorrhagic stroke by elevating blood pressure and impairing cerebrovascular endothelial function. Additionally, both age- and/or disease-related immune dysfunction and enhanced catecholamine release secondary to anxiety and stress may also aggravate central nervous system symptoms of severe acute respiratory syndrome coronavirus 2 infection. Thus, assessment of systemic inflammatory biomarkers and tight control of hemodynamic parameters upon admission are crucial to minimize mortality and morbidity in coronavirus disease 2019 patients with central nervous system symptoms suggestive of incipient stroke.

Influence of COVID-19 on Cerebrovascular Disease and its Possible Mechanism.

The global spread of COVID-19 has caused a substantial societal burden and become a major global public health issue. The COVID-19 elderly population with hypertension, diabetes, cardiovascular, and cerebrovascular diseases are at risk. Mortality rates are highest in these individuals if infected with COVID-19. Although the lungs are the main organs involved in acute respiratory distress syndrome caused by COVID-19 infection, COVID-19 triggers inflammatory and immune mechanisms, inducing a "cytokine storm" that aggravates disease progression and may lead to death. Presently, effective drugs are lacking, although current studies have confirmed that drugs with therapeutic potential include redaciclovir, lopinavir/ritonavir combined with interferon-ß, convalescent plasma, and monoclonal antibodies. Currently, the most reasonable and effective way to prevent COVID-19 is to control the source of infection, terminate routes of transmission, and protect susceptible populations. With the rise of COVID-19 in China and worldwide, further prevention, diagnosis, and treatment measures are a critical unmet need. Cerebrovascular disease has high incidence, disability rate, and fatality rate. COVID-19 patient outcomes may also be complicated with acute stroke. This paper summarizes the influence of COVID-19 on cerebrovascular disease and discusses possible pathophysiological mechanisms to provide new angles for the prevention and diagnosis of this disease.