Abstract 184: Comparing Characteristics and Outcomes of Ruptured and Unruptured Mycotic Aneurysms: A Single Center Study

Abstract

Introduction Infectious intracranial aneurysms (IIAs), commonly referred to as mycotic aneurysms, are a common sequela of infective endocarditis (IE). Approximately 65% of patients found to have IIAs also have IE, and IIAs occur in up to 10% of patients with IE. Clinically, it is important to be able to identify IIAs as well as their etiologies to adequately manage these insidious vascular lesions. Mortality rates have been reported up to 30% for unruptured and 80% for ruptured mycotic aneurysms. With upcoming advances in the neuro‐endovascular field, there has been a surge in pursuing endovascular therapies to secure these aneurysms which have yielded positive outcomes. We present a single‐center experience describing the characteristics and outcomes of ruptured and unruptured IIAs. Methods This is a single‐center retrospective observational study of patients admitted with IE who developed IIAs and were admitted at our institute from 2016 to 2022. Descriptive statistics were performed using SAS statistical software and Microsoft Excel. Results Out of a total of 862 patients with IE, 25 patients (3.0%) were identified to have 41 IIAs (single aneurysm in 18 patients and multiple aneurysms in 7 patients). The median (IQR) age of our population was 45 (27‐65) years, with 28/41 (68.3%) male patients. The most common location of IIAs was the distal segments of the posterior and middle cerebral arteries in both groups. The overall mean (minimum‐maximum) size of all IIAs was 2.8 (0.2‐11) mm. Of these 41 IIAs, 24/41 (58.5%) were ruptured and 17/41 (41.5%) were unruptured. A total of 14/24 (58.3%) ruptured IIAs were treated vs. none were treated in the unruptured IIAs group (P=0.001). The average (minimum‐maximum; mm) size of ruptured IIAs was 3.3 (0.2‐11) vs. 2.1 (0.8‐5) in the unruptured IIAs group (P=0.324). More patients died while hospitalized with ruptured aneurysms vs unruptured aneurysms at 29.1% and 11.7%, respectively (P=0.18). Additionally, 16.7% of those in the ruptured group were discharged home, whereas 41.2% in the unruptured IIA group were discharged home (P=0.08). Conclusion This study emphasizes the significant mortality rate observed among patients with ruptured IIAs. Clinicians should remain vigilant when screening patients. Our study suggests that ruptured IIAs should be secured while unruptured IIAs may be monitored closely.