Management of cerebral venous thrombosis due to adenoviral COVID-19 vaccination.

OBJECTIVE Cerebral venous thrombosis caused by vaccine-induced immune thrombotic thrombocytopenia (VITT-CVT) is a rare adverse effect of adenovirus-based SARS-CoV-2 vaccines. In March 2021, after autoimmune pathogenesis of VITT was discovered, treatment recommendations were developed. These comprised immunomodulation, non-heparin anticoagulants, and avoidance of platelet transfusion. The aim of this study was to evaluate adherence to these recommendations and its association with mortality. METHODS We used data from an international prospective registry of patients with CVT after adenovirus-based SARS-CoV-2 vaccination. We analyzed possible, probable or definite VITT-CVT cases included until 18 January 2022. Immunomodulation entailed administration of intravenous immunoglobulins and/or plasmapheresis. RESULTS 99 VITT-CVT patients from 71 hospitals in 17 countries were analyzed. Five of 38 (13%), 11/24 (46%), and 28/37 (76%) of patients diagnosed in March, April, and from May onwards, respectively, were treated in-line with VITT recommendations (p