Repeated Cardioembolic Stroke after COVID-19 mRNA Vaccination: A Case Report

OBJECTIVE: There have been no reports suggesting a relationship between the COVID-19 mRNA vaccines that encodes the spike glycoprotein of SARS-CoV-2 and cerebrovascular disease. A case of repeated cardioembolic stroke after vaccination with the BNT162b2 (Pfizer) COVID-19 mRNA vaccine is presented. METHODS: Imaging and laboratory findings, treatment decisions, and the outcome of this case are presented. RESULTS: An 83-year-old Japanese woman developed right hemiplegia and motor aphasia three days after receiving her first dose of the BNT162b2 (Pfizer) COVID-19 mRNA vaccine. She had been taking rivaroxaban for persistent atrial fibrillation for 10 years, but had no symptomatic ischemic strokes. On magnetic resonance imaging (MRI) the left middle cerebral artery (MCA) was occluded. Intravenous recombinant tissue-plasminogen activator (rt-PA) therapy and mechanical thrombectomy were performed, and she recovered almost fully. However, three days after the second dose, she developed left hemiplegia and left hemispatial neglect. MRI showed occlusion of the right MCA. Only mechanical thrombectomy was performed again, but it could not be resumed due to the hard thrombus. DISCUSSION: In this case, it is difficult to exclude a causal relationship between the COVID-19 mRNA vaccine and ischemic stroke. This association needs to be carefully monitored.