Management of Unruptured Infectious Intracranial Aneurysms in Infective Endocarditis: A Case Report and Literature Review.

Infectious intracranial aneurysms (IIAs) are rare lesions with fragile arterial walls located within the aneurysms, carrying a high risk of rupture. Standard management often involves antibiotic therapy and parent artery occlusion; however, the latter carries a significant risk of cerebral infarction. This report presents a case of an unruptured IIA following cerebral infarction, successfully treated with coil embolization while preserving the parent artery. A 54-year-old man with a history of smoking and alcohol consumption presented with fever and impaired consciousness. Upon admission, he exhibited signs of sepsis and meningitis, with a Glasgow Coma Scale score of 8. Imaging revealed multiple cerebral infarctions alongside embolic lesions in the kidney and spleen. Transthoracic echocardiography confirmed mitral valve infective endocarditis. The patient was started on antibiotics and underwent mitral valve repair on hospital day 4. On hospital day 44, MRI and magnetic resonance angiography (MRA) identified a 5-mm unruptured aneurysm in the left middle cerebral artery, consistent with an IIA. Coil embolization was performed on hospital day 60 under general anesthesia, achieving complete aneurysm obliteration without compromising the parent artery. Postoperatively, the patient experienced no new infarctions and demonstrated a favorable recovery, leading to discharge on hospital day 110. Follow-up MRI and MRA performed 18 months post-treatment confirmed the absence of aneurysm recurrence. This case highlights the importance of individualized treatment strategies in managing IIAs. While parent artery occlusion remains the standard approach, coil embolization offers a viable alternative in select cases, particularly for preserving parent artery integrity and reducing the risk of cerebral infarction.