Cerebral venous sinus thrombosis following vaccination against COVID-19: A UK multicentre cohort study

Background and Aims: A new syndrome of vaccine-induced immune thrombotic thrombocytopenia (VITT) has emerged as a rare side-effect of vaccination against COVID-19. Cerebral venous sinus thrombosis (CVST) is its most common manifestation but has not previously been described in detail. Our objectives were to document the features of post-vaccination CVST with and without VITT and to assess whether VITT is associated with a worse outcome. Methods: We collected clinical characteristics, laboratory results and radiological features on admission of patients with CVST following vaccination against COVID-19. We compared the VITT and non-VITT groups for the proportion of patients who were dead or dependent at the end of admission. Results: 70 patients with CVST following vaccination against COVID-19 had VITT, and 25 did not. The median age of the VITT group (47 years) was lower than in the non-VITT group (57 years, p = 0.0045). Patients with VITT-associated CVST had more intracranial veins thrombosed (median 3) than non-VITT patients (median 2, p = 0.041) and more frequently had extracranial thrombosis (44%) than non-VITT patients (4%, p = 0.0003). Death or dependency (mRS 3-6) occurred more frequently in VITTassociated CVST (47%) than in non-VITT CVST (13%, p = 0.0020). This adverse outcome was less frequent in VITT patients who received nonheparin anticoagulation (36%) than in those who did not (75%, p = 0.0031) and in those who received intravenous immunoglobulin (40%) than in those who did not (73%, p = 0.022). Conclusions: CVST is more severe in the context of VITT. Non-heparin anticoagulants and immunoglobulin may improve outcome of VITTassociated CVST.