Ruptured distal intracranial mycotic aneurysms (MAs) are devastating complications of infective endocarditis (IE). Rapid aneurysm exclusion is essential for reducing the risk of rebleeding and permitting safe cardiac surgery. Endovascular embolization with n-butyl cyanoacrylate (n-BCA) provides immediate and durable aneurysm occlusion, often with sacrifice of the parent vessel. Long-term recovery depends on systemic infection control, baseline neurological status, and surgical candidacy.

We reviewed three consecutive patients with IE-associated ruptured distal MCA aneurysms treated with n-BCA embolization. Data collected included clinical presentation, microbiologic profiles, embolization technique, adjunctive neurosurgical and cardiac interventions, and neurological outcomes (initial NIHSS, discharge NIHSS, and modified Rankin Scale [mRS]).

All aneurysms were successfully excluded with n-BCA on the first attempt, underscoring the high technical reliability of this approach. A 61-year-old man with Streptococcus viridans IE underwent embolization and craniotomy but died of refractory intracranial hypertension (mRS 6). A 34-year-old woman with E. faecalis IE required embolization, hemicraniectomy, and subsequent dual valve replacement; she survived with expressive aphasia and partial recovery (NIHSS 12–15, mRS 4). A 45-year-old woman with E.faecalis and Serratia bacteremia underwent embolization of a ruptured distal M3 MCA aneurysm and, though ineligible for valve surgery, achieved near-complete recovery with mild dysarthria (NIHSS 1–2, mRS 1–2). Despite uniform angiographic cure, neurological outcomes ranged from death to near-complete recovery, reflecting systemic infection burden, initial neurological injury, and valve surgery eligibility rather than the embolization procedure itself. 

n-BCA embolization offers quick, lasting closure of ruptured distal MAs and should be considered the foundation of modern treatment. It allows safe progression to life-saving valve replacement in patients with IE. Although final outcomes are still affected by systemic and surgical factors, embolization is becoming the standard of care for this high-risk group.