A 52-year-old Caucasian woman was admitted to emergency department for a suspected stroke. Her past medical history was unremarkable. She was on therapy with oral contraception. She had the first dose of ChAdOx1 nCov-19 vaccine 15 days before. Sickness, nausea, and vomiting were reported since the previous day. At arrival, she was unresponsive, with head and eyes deviation to the right and left hemiparesis. The vital parameters were normal. No other signs of thrombosis or bleeding were noticed at physical examination. Sars-Cov2 rapid and molecular nasopharyngeal tests were both negative.
Head CT scan revealed diffuse brain edema and spontaneous hyperdensity in the superior sagittal sinus and the straight sinus according with a diagnosis of massive cerebral venous sinus thrombosis (CVST); CT angiography (CTA) confirmed a diffuse CVST (Fig. 1a). A total body CECT scan ruled out venous thrombosis in other sites.
Blood tests revealed a severe isolated thrombocytopenia (40.000/mmc) and a slight D-dimer increase (18 mcg/ml).
Due to the clinical suspect of VITT, dexamethasone (40 mg i.v. daily for 4 days), high-dose immunoglobulins (1 g/kg body weight daily for 2 days i.v.), and low dose of fondaparinux (2.5 mg subcutaneously) were administered in less than an hour since hospital admission (Fig. 2), according to SISET guidelines. In the following hours, IgG against PF4/heparin (ELISA) and functional platelet aggregation test (PAT heparin-induced platelet aggregation) resulted positive, thus confirming the diagnosis of VITT. A subsequent brain MR imaging confirmed the diffuse cerebral venous thrombosis (Fig. 1b). At the end of the MRI, after a tonic–clonic seizure, the patient experienced progressive neurological deterioration; therefore, she was intubated. The neuroradiologist suggested a neuroendovascular treatment and after a collegial discussion, we decided to proceed after platelet transfusion. Thrombectomy was performed both with aspiration using large bore aspiration catheter and with multiple embricated stent-retrievers. After many passages, the superior sagittal sinus, torcular, and right transverse and sigmoid sinuses were recanalized with residual thrombi in cortical veins. The straight sinus was not completely reopened, however obtaining a small channel draining the internal cerebral veins. The mechanical thrombectomy allowed flow restoration both in superficial and deep cerebral venous systems but not in cortical veins (Fig. 1c). At the end of the procedure, day 0, the patient was admitted in ICU where she stayed for 12 days. A new brain and chest CT scan excluded bleeding and malignant brain edema. We decided to place intraparenchymal monitoring of intracranial pressure (ICP) before starting full-dose anticoagulation. Frequent periodic epileptic activity was recorded on continuous electroencephalographic monitoring; therefore, antiepileptic treatment was increased (Levetiracetam 3 g daily in association with Lacosamide 400 mg daily). Since day 1, platelet count starts increasing and fully recovered on day 9. Starting from day 2, in agreement with the hematologist, incremental dosage of fondaparinux was set up until full anticoagulant dose of fondaparinux (7.5 mg s.c./die). Screening tests for congenital and acquired thrombophilia were normal.
MRI was repeated on day 11, showing complete patency of the superior sagittal, torcular, and left transverse and sigmoid sinuses, whereas the right transverse and sigmoid sinuses were again occluded. Both internal cerebral veins, the vein of Galen and the straight sinus, were patent, although with a faint flow. Brain edema was regressed whereas signs of microbleeds in right perirolandic cortex and right thalamus were unchanged.
Progressive neurological improvement was observed until recovery of consciousness on day 9; on day 12, the patient was extubated and transferred to Neurology Unit. After 22 days, the patient returned home with a complete neurological recovery. She was discharged with antiepileptic drugs under reduction and warfarin with a target INR between 2 and 3.