Abstract
BACKGROUND: Flow diverter stent placement for unruptured intracranial aneurysms requires intensive antithrombotic therapy, which can lead to unexpected hemorrhagic complications. However, standard protocols for managing such conditions have not been established. A rare case of idiopathic esophageal submucosal hematoma after flow diverter stent placement, successfully managed with the continuation of antithrombotic therapy, is reported. OBSERVATIONS: A 76-year-old woman had undergone coil embolization 12 years earlier for a ruptured right paraclinoid internal carotid artery aneurysm. Follow-up imaging showed recurrence of the aneurysm, and she was admitted for flow diverter stent placement. She received dual antiplatelet therapy (aspirin and prasugrel) for 2 weeks prior to treatment, along with appropriate systemic heparinization during the procedure. One hour after treatment, she developed severe chest pain. Contrast-enhanced CT imaging showed an esophageal submucosal hematoma without active bleeding. Conservative treatment was started without discontinuing antiplatelet therapy, resulting in the near-complete resolution of the hematoma on CT imaging by day 11, and she was discharged on day 21. LESSONS: Although rare, idiopathic esophageal submucosal hematoma should be considered a potential complication when a patient complains of chest pain after endovascular treatment. When antiplatelet therapy is required and no active bleeding is present, continuation of antiplatelet therapy can be a viable option under careful observation. https://thejns.org/doi/10.3171/CASE25495.