Does aneurysm side influence the infarction side and patients´ outcome after subarachnoid hemorrhage?

Abstract

Background The prognostic factors and outcome of aneurysms appear to be dependent on its locations. Therefore, we compared left- and right- sided aneurysms in patients with aneurysmal subarachnoid hemorrhage (SAH) in terms of differences in outcome and prognostic factors. Methods Patients with SAH were entered into a prospectively collected database. A total of 509 patients with aneurysmal subarachnoid hemorrhage were retrospectively selected and stratified in two groups depending on side of ruptured aneurysm (right n = 284 vs. left n = 225). Midline aneurysms of the basilar and anterior communicating arteries were excluded from the analysis. Outcomes were assessed using the modified Rankin Scale (mRS; favorable (mRS 0–2) vs. unfavorable (mRS 3–6)) six months after SAH. Results We did not identify any differences in outcome depending on left- and right-sided ruptured aneurysms. In both groups, the significant negative predictive factors included clinical admission status (WFNS IV+V), Fisher 3- bleeding pattern in CT, the occurrence of delayed cerebral ischemia (DCI), early hydrocephalus and later shunt-dependence. The side of the ruptured aneurysm does not seem to influence patients´ outcome. Interestingly, the aneurysm side predicts the side of infarction, with a significant influence on patients´ outcome in case of left-sided infarctions. In addition, the in multivariate analysis side of aneurysm was an independent predictor for the side of cerebral infarctions. Conclusion The side of the ruptured aneurysms (right or left) did not influence patients’ outcome. However, the aneurysm-side predicts the side of delayed infarctions and outcome appear to be worse in patients with left-sided infarctions.