Data from: Clinical complications and outcomes of angiographically negative subarachnoid hemorrhage

Objective: To define the in-hospital course, complications, short- and
long-term functional outcomes of patients with angiographically negative
subarachnoid hemorrhage (anSAH), particularly those with
aneurysmal-pattern anSAH (aanSAH). Methods: Retrospective cohort study of
patients with aneurysmal subarachnoid hemorrhage (aSAH), aanSAH and
perimesencephalic-pattern anSAH (panSAH) treated at a single tertiary
referral center between January 2006 and April 2018. Ninety-nine patients
with anSAH (33 aanSAH and 66 panSAH) and 464 patients with aSAH were
included in this study. Outcomes included symptomatic hydrocephalus
requiring CSF drainage, need for ventriculoperitoneal shunt (VPS),
radiographic vasospasm, delayed cerebral ischemia (DCI), radiographic
infarction, disability level within one year of ictus and at last clinical
follow-up as defined by modified Rankin Scale (mRS). Results: Patients
with aanSAH and panSAH had similar rates of DCI and radiologic infarction,
and patients with aanSAH had significantly lower rates compared to aSAH
(P≤0.018). Patients with aanSAH were more likely than those with panSAH to
require temporary CSF diversion and VPS (P≤0.03), with similar rates to
those seen in aSAH. Only one patient with anSAH died in the hospital.
Compared to those with aSAH, patients with aanSAH were significantly less
likely to have a poor functional outcome within one year of ictus (OR
0.26, 95% CI 0.090 – 0.75) and at last follow-up (HR 0.30, 95% CI 0.19 –
0.49, P=0.002). Conclusions: DCI is very uncommon in anSAH, but patients
with aanSAH have a similar need for short- and long-term CSF diversion to
patients with aSAH. Nevertheless, patients with aanSAH have significantly
better short- and long-term outcomes.