Prevalence and Clinical Characteristics of Isolated Intraventricular Hemorrhage

Isolated intraventricular hemorrhage (IVH) is a rare phenotype of intracerebral hemorrhage (ICH), and its mechanistic basis is poorly understood.

This retrospective study used a prospectively collected single-center database of patients treated between December 2010 and December 2022. Patients with ICH were classified into isolated IVH and intraparenchymal hemorrhage (IPH). The clinical profiles of patients with isolated IVH and IPH were compared.

Of 2,310 patients with acute ICH, 41 were excluded because of underlying vascular lesions, trauma, and tumor as possible causes. Of the remaining 2,269 patients, there were 23 patients (1%) with isolated IVH (female 44%; mean age, 73 ± 11 years) and 2,246 (99%) with IPH (43%; 71 ± 13 years). Compared with the IPH group, the isolated IVH group had a higher frequency of diabetes mellitus (35% vs. 16%) and prior anticoagulant use (44% vs. 13%). Diabetes mellitus (adjusted odds ratio: 2.50 [95% confidence interval, 1.03-6.07]) and prior anticoagulant use (3.74 [1.05-13.33]) were independently associated with isolated IVH. Compared with the IPH group, the isolated IVH group had a significantly lower NIHSS score at discharge (median 2 [interquartile range 0-12] vs. 8 [2-18], p = 0.011). Unfavorable outcome, defined as mRS 4-6, was marginally less common at 90 days (27% vs. 47%, p = 0.061) for isolated IVH than for IPH.

Compared to IPH, isolated IVH was more frequently associated with prior anticoagulant use and diabetes mellitus and had a tendency for milder neurologic deficits and better functional outcomes.