Emergent causes of hemiparesis including stroke and seizure will be discussed by differential and treatment, including a discussion regarding why a provider could reason for a diagnosis definitively and act in that regard. In this case, a patient had an acute type A aortic dissection with the initial presentation of hemiparesis. Administering tissue plasminogen activator for the alternative differential would have led to a poor outcome and an emergent change of plan was indicated. The goal is to broaden the differential on a commonly taught topic as this patient presented as near-miss case that had a good outcome with prompt treatment.
