Introduction: Infectious intracranial aneurysm (IIA) can complicate infective endocarditis (IE). We aim to describe the characteristics of IIA and to assess indications for cerebral angiography.
Methods: We reviewed IIAs among 116 consecutive active IE by Duke’s criteria with neurological consultation or admission to stroke neurology service in a single tertiary referral center from January 2015 to July 2016. Susceptibility weighted imaging (SWI) hemorrhage was defined as low signal on SWI in sulci or parenchyma that was not apparent on CT.
Results: Of 116 patients, 74 persons (63.8%, mean age of 54) underwent digital subtraction angiography (DSA). IIAs were identified in 13 (17.6%). All of 13 IIAs were unruptured and only one IIA had unrelated intracranial hemorrhage on CT. None of the IIA was seen with CTA or MRA. Eleven (85%) IIAs had clinical strokes (10 ischemic strokes, 1 intracerebral hemorrhage, median NIH stroke scale 3), and 2 neurologically asymptomatic with abnormal MRI. Six of 9 IIAs had SWI hemorrhage in sulci or parenchyma (5 in sulci, 5 in parenchyma, and 1 in both) and all of the lesions were in the vicinity of IIA. Contrast MRI was performed in 7 IIAs, and 4 IIAs had enhancements, all of which were present near the location of IIAs. Ischemic stroke, intracranial hemorrhage, intravenous drug abuse, and type of valve were not associated with the presence of IIA. Of 13 IIAs, 3 remained on antibiotic alone, 5 had antibiotic with coil embolization, and, 5 had antibiotic with glue embolization. Ten patients with IIAs had valvular surgery, including one person with untreated IIA. Out of all patients with IIA, only one intracerebral hemorrhage occurred as perioperative complication unrelated to treated IIA.
Conclusions: IIAs were found in approximately one fifth of IE persons who underwent DSA. Imaging characteristics such as SWI hemorrhage in sulci or parenchyma and contrast enhancement appear to correlate with the presence of IIA. DSA should be performed when they are present.