ABSTRACT NUMBER: ESOC2026A2191 POST ISCHEMIC HYPERPERFUSION, A CASE REPORT

Abstract Background and aims Post-ischemic hyperperfusion can be observed following acute stroke after arterial recanalization. This radiological finding may lead to diagnostic confusion, particularly in patients with nonspecific neurological symptoms. It is important to consider a vascular etiology when this imaging pattern is present. The aim of this case is to highlight the relevance of cardioembolic etiology in this context Methods Descriptive presentation of a clinical case. Results A 68-year-old man with a history of atrial fibrillation on edoxaban presented with a prodromal viral-like syndrome, leading him to miss his usual anticoagulant dose. He subsequently attended the emergency department with visual field defects, visual extinction, hemianopia, and bradypsychia, without other focal neurological deficits. Multimodal CT showed a poorly defined hypodense area in the right temporoparietal region without hemorrhage, associated with hyperperfusion throughout the affected territory. Given the initial suspicion of encephalitis as the primary diagnosis, a lumbar puncture was performed, showing no significant cerebrospinal fluid abnormalities or elevation of serum inflammatory markers. During hospitalization, brain MRI with diffusion was performed, revealing an ischemic lesion in the superior and inferior subdivisions of the right middle cerebral artery, with a gyral pattern of hyperperfusion. Conclusions In patients presenting with nonspecific neurological symptoms and hyperperfusion on acute imaging, vascular etiology—particularly cardioembolic—should be considered. Post-ischemic hyperperfusion may be related to spontaneous recanalization via the endogenous fibrinolytic system and to blood–brain barrier disruption. Recognition of this phenomenon is clinically relevant, as it influences treatment decisions both in the acute phase and in long-term management. Conflict of interest Daniel Antonio Ginarte Milanés: Nothing to disclose Figure 1 - belongs to Results