stroke associated with sars-cov-2 infection and its pathogenesis: a systematic review

Introduction: the change of stroke incidence during the covid-19 pandemic period andthe proposed mechanisms of the relationship between sars-cov-2 and stroke is reviewed.methods: web of science, pmc/medline, and scopus databases were searched until july2020 without time and language limitations. after quality assessment, 22 articles were includedin this study.results: based on the results, it is impossible to conclude any definite relationship betweenthe rising or decreasing stroke frequency or the shift in the ischemic and hemorrhagic ratioand sars-cov-2 infection. however, it appears that sars-cov-2 infection has somecorrelation with stroke. the supposed mechanisms for the sars-cov-2-related hemorrhagicstroke include 1) sars-cov-2-related vasculopathy with the endothelial damage of smallvessels, 2) viral infection-induced platelet dysfunction or thrombocytopenia, and 3) activationof the proinflammatory cascade leading to coagulopathy. the helpful strategies are receivingtherapeutic anticoagulation for high d-dimer or a known thrombus due to sars-cov-2infection, as well as using extracorporeal membrane oxygenation (ecmo) in some patients.furthermore, the possible mechanisms for the sars-cov-2-related ischemic stroke include1) dysregulation of angiotensin-converting enzyme 2 (a key host cellular receptor for sarscov-2)-related physiologic functions, 2) endothelial cell damages, 3) thrombo-inflammation,and 4) coagulopathy and coagulation abnormalities related to sars-cov-2 infection.conclusion: a better understanding of the sars-cov-2 pathogenesis and its relation toneurologic abnormalities such as stroke can help to design new therapeutic approaches.