Primary intraventricular hemorrhage outcomes in the CLEAR III trial

Background: Intraventricular hemorrhage occurs due to intracerebral hemorrhage with intraventricular extension or without apparent parenchymal involvement, known as primary intraventricular hemorrhage. Aims: We evaluated the prognosis of primary intraventricular hemorrhage patients in the CLEAR III trial (Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage). Methods: In patients with primary intraventricular hemorrhage versus those with secondary intraventricular hemorrhage, we compared intraventricular alteplase response and outcomes including modified Rankin Scale, Barthel Index, National Institutes of Health Stroke Scale (NIHSS), and extended Glasgow Outcome Scale (eGOS) at 30, 180, and 365 days. Outcomes were also compared in primary intraventricular hemorrhage patients who received intraventricular alteplase versus placebo (normal saline) and in matched primary and secondary intraventricular hemorrhage patients using inverse-probability-weighted regression adjustment. Results: Of 500 patients enrolled in CLEAR III, 46 (9.2%) had primary intraventricular hemorrhage. Combining both treatment groups, primary intraventricular hemorrhage patients had larger intraventricular hemorrhage volumes (median: 34.2 mL vs. 20.8 mL, p < 0.01) but similar intraventricular hemorrhage removal (51.0% vs. 59.0%, p = 0.24) compared to secondary intraventricular hemorrhage patients, respectively. Confirming previous studies, primary intraventricular hemorrhage patients achieved better NIHSS, modified Rankin Scale, Barthel Index, and eGOS scores at days 30, 180, and 365, respectively (all p < 0.01), although mortality was similar to secondary intraventricular hemorrhage patients; matching analysis yielded similar results. Primary intraventricular hemorrhage patients who received intraventricular alteplase (n = 19) and saline (n = 27) achieved similar outcomes. Conclusions: In CLEAR III, primary intraventricular hemorrhage patients who survived achieved better long-term outcomes than surviving secondary intraventricular hemorrhage patients with similar mortality. Outcomes and safety were similar between primary intraventricular hemorrhage patients receiving alteplase and those receiving saline.