Acute internal carotid artery occlusion following administration of Andexanet alfa for the reversal of direct factor Xa inhibitors in patients with cerebral hemorrhage

An 87-year-old woman receiving aspirin and apixaban with a history of large artery atherosclerotic stroke, and pulmonary embolism presented to the hospital for aphasia and right hemiplegia. A head CT scan showed 18-ml hematoma in the left thalamus. Low-dose Andexanet alfa was administered 84 minutes after the onset of stroke, and 10 hours and 24 minutes after the last dose of apixaban. Three hours later after admission, she had flaccid hemiplegia and became comatose. CT and CT angiography revealed occlusion of left internal carotid artery (ICA) and no evidence of hematoma expansion. Although repetitive mechanical thrombectomy resulted in recanalization (modified TICI 2b), carotid ultrasound revealed the occlusion of left ICA on next day. On day 7, she died of brain herniation following extensive cerebral infarction. It has been reported that some patients did experience thrombotic events after administration of Andexanet alfa. Our case illustrates that even large vessel occlusion might occur after intravenous injection of Andexanet alfa. Thus, careful follow-up, including cerebrovascular imaging, is required immediately after administration of Andexanet alfa.