1117. In-Hospital Complications and Clinical Outcomes in Angiographically Negative Subarachnoid Hemorrhage

Authors: Cody Lee Nesvick, MD; Soliman Oushy, MD; Lorenzo Rinaldo, MD, PhD; Eelco Wijdicks, MD, PhD; Giuseppe Lanzino, MD; Alejandro Rabinstein, MD (Rochester, MN)


Many patients with subarachnoid hemorrhage will have a normal cerebral angiogram. The complications and outcomes of patients with angiographically negative subarachnoid hemorrhage (anSAH) are not well-defined. The goal of this study was to define the hospital course, complications and outcomes of patients with aneurysmal-pattern anSAH (aanSAH) compared to those with perimesencephalic-pattern anSAH (panSAH) and aneurysmal subarachnoid hemorrhage (aSAH).


We performed a retrospective cohort study of patients with aneurysmal and angiographically negative subarachnoid hemorrhage treated at Mayo Clinic between 2006 and 2018. Ninety-nine patients with anSAH (33 aanSAH, 66 panSAH) and 474 patients with aSAH were included.


Patients with aanSAH and panSAH had similar rates of DCI and radiologic infarction, and patients with aanSAH had significantly lower rates compared to aSAH (DCI: OR = 0.090, 95% CI 0.012 – 0.66; infarction: OR 0.26, 95% CI 0.078 – 0.86). Patients with aanSAH were more likely than those with panSAH to require temporary CSF diversion (OR 6.25, 95% CI 2.50 – 15.6) and ventriculoperitoneal shunting (VPS; OR 4.67, 95% CI 1.09 – 20.04), with similar rates to those seen in aSAH (CSF diversion: OR 1.04, 95% CI 0.49 – 2.19; VPS: OR 0.62, 95% CI 0.25 – 1.55). Compared to those with aSAH, patients with aanSAH were less likely to have a poor functional outcome (modified Rankin score > 2, including death) within one year of ictus (OR 0.25, 95% CI 0.086 – 0.72) and at last follow-up (HR 0.27, 95% CI 0.17 – 0.43).


These results demonstrate that DCI is very uncommon in anSAH, but patients with aanSAH have a similar need for CSF diversion to patients with aSAH. Patients with aanSAH have a significantly better short- and long-term prognosis compared to patients with aSAH.