Background and Purpose: We aimed to investigate the rate of hospital admissions for cerebrovascular events and of revascularization treatments for acute ischemic stroke in Italy during the coronavirus disease 2019 (COVID-19) outbreak. Methods: The Italian Stroke Organization performed a multicenter study involving 93 Italian Stroke Units. We collected information on hospital admissions for cerebrovascular events from March 1 to March 31, 2020 (study period), and from March 1 to March 31, 2019 (control period). Results: Ischemic strokes decreased from 2399 in 2019 to 1810 in 2020, with a corresponding hospitalization rate ratio (RR) of 0.75 ([95% CI, 0.71–0.80] P <0.001); intracerebral hemorrhages decreased from 400 to 322 (hospitalization RR, 0.81 [95% CI, 0.69–0.93]; P =0.004), and transient ischemic attacks decreased from 322 to 196 (hospitalization RR, 0.61 [95% CI, 0.51–0.73]; P <0.001). Hospitalizations decreased in Northern, Central, and Southern Italy. Intravenous thrombolyses decreased from 531 (22.1%) in 2019 to 345 in 2020 (19.1%; RR, 0.86 [95% CI, 0.75–0.99]; P =0.032), while primary endovascular procedures increased in Northern Italy (RR, 1.61 [95% CI, 1.13–2.32]; P =0.008). We found no correlation ( P =0.517) between the hospitalization RRs for all strokes or transient ischemic attack and COVID-19 incidence in the different areas. Conclusions: Hospitalizations for stroke or transient ischemic attacks across Italy were reduced during the worst period of the COVID-19 outbreak. Intravenous thrombolytic treatments also decreased, while endovascular treatments remained unchanged and even increased in the area of maximum expression of the outbreak. Limited hospitalization of the less severe patients and delays in hospital admission, due to overcharge of the emergency system by COVID-19 patients, may explain these data.

Vaccine-induced thrombotic thrombocytopenia with cerebral venous thrombosis is a syndrome recently described in young adults within two weeks from the first dose of the ChAdOx1 nCoV-19 vaccine. Here we report two cases of malignant middle cerebral artery (MCA) infarct and thrombocytopenia 9-10 days following ChAdOx1 nCoV-19 vaccination. The two cases arrived in our facility around the same time but from different geographical areas, potentially excluding epidemiological links; meanwhile, no abnormality was found in the respective vaccine batches. Patient 1 was a 57-year-old woman who underwent decompressive craniectomy despite two prior, successful mechanical thrombectomies. Patient 2 was a 55-year-old woman who developed a fatal bilateral malignant MCA infarct. Both patients manifested pulmonary and portal vein thrombosis and high level of antibodies to platelet factor 4-polyanion complexes. None of the patients had ever received heparin in the past before stroke onset. Our observations of rare arterial thrombosis may contribute to assessment of possible adverse effects associated with COVID-19 vaccination.

The risk of stroke and cerebrovascular disease complicating infection with SARS-CoV-2 has been extensively reported since the onset of the pandemic. The striking efforts of many scientists in cooperation with regulators and governments worldwide have rapidly brought the development of a large landscape of vaccines against SARS-CoV-2. The novel DNA and mRNA vaccines have offered great flexibility in terms of antigen production and led to an unprecedented rapidity in effective and safe vaccine production. However, as mass vaccination has progressed, rare but catastrophic cases of thrombosis have occurred in association with thrombocytopenia and antibodies against PF4 (platelet factor 4). This catastrophic syndrome has been named vaccine-induced immune thrombotic thrombocytopenia. Rarely, ischemic stroke can be the symptom onset of vaccine-induced immune thrombotic thrombocytopenia or can complicate the course of the disease. In this review, we provide an overview of stroke and cerebrovascular disease as a complication of the SARS-CoV-2 infection and outline the main clinical and radiological characteristics of cerebrovascular complications of vaccinations, with a focus on vaccine-induced immune thrombotic thrombocytopenia. Based on the available data from the literature and from our experience, we propose a therapeutic protocol to manage this challenging condition. Finally, we highlight the overlapping pathophysiologic mechanisms of SARS-CoV-2 infection and vaccination leading to thrombosis.

The pathophysiology of COVID-19-associated coagulopathy is complex and not fully understood. SARS-CoV-2 spike protein (SP) may activate platelets and interact with fibrin(ogen). We aimed to investigate whether isolated SP can be present in clots retrieved in COVID-19 patients with acute ischemic stroke (by mechanical thrombectomy) and myocardial infarction. In this pilot study, we could detect SP, but not nucleocapsid protein, on platelets of COVID-19 patients’ thrombi. In addition, in all three COVID-19 thrombi analyzed for molecular biology, no SARS-CoV-2 RNA could be detected by real-time polymerase chain reaction. These data could support the hypothesis that free SP, besides the whole virus, may be the trigger of platelet activation and clot formation in COVID-19.

Not available.