Subarachnoid hemorrhage in patients without a vascular defect - A retrospective observational study

Abstract

Aim: Angiogram-negative subarachnoid hemorrhage (AN-SAH) is defined as subarachnoid hemorrhage with no vascular defect detected in radiological imaging. In approximately 15% of patients with subarachnoid hemorrhage, no visible bleeding cause is found during the initial examination. Our main objective of the study was to analyze epidemiological data and clinical conditions of AN-SAH patients in comparison with patients suffering from subarachnoid hemorrhage caused by a ruptured aneurysm (A-SAH). Methods: This was a single-center retrospective cohort study carried out in Heliodor Święcicki Hospital in Poznań, Poland. All the patients underwent Computed Tomography (CT) scans and Digital Subtraction Angiography (DSA). If no vascular defect was presented, a follow-up after two weeks post-initial examination was suggested. Obtained data were analyzed in Statistica 13. Results: We included 564 patients admitted to the hospital between April 2016 to May 2021 with subarachnoid hemorrhage. 60 of all patients were diagnosed with angiogram-negative subarachnoid hemorrhage (AN-SAH). The average age of the AN-SAH patients group was similar to the A-SAH patients group (53 ± 11.38 vs. 56.8 ± 14.1). Contrary to the A-SAH patients where women were the dominant sex (66.27%), the AN-SAH group comprises mostly men (65%). The clinical condition measured by Hunt Hess (HH) score for both patient groups was more favorable for the AN-SAH group (the median HH score was I) than those of patients with a ruptured aneurysm (the median HH score was II). Conclusion: There is a significant difference between clinical outcome and gender distribution of AN-SAH patients in comparison to A-SAH patients.