Acute ischemic stroke with or without asymptomatic intracranial hemorrhage after endovascular treatment: a propensity-score matching study.

Background: The long-term follow-up of asymptomatic intracranial hemorrhage (aICH) in patients with acute ischemic stroke after endovascular treatment (EVT) remains controversial.ObjectiveTo evaluate the potential effect of aICH in a real-world practice setting using a matched prospective database.

Methods: This observational cohort study enrolled patients between January 2015 and December 2022 in a prospective database. Eligible patients with occlusions in the anterior circulation were given endovascular treatment and achieved successful reperfusion. The primary outcome was functional independence (modified Rankin Scale (mRS) score 0-2). Propensity score (PS)-weighted multivariable logistic regression analyses were adjusted and were repeated in subsequent 1:1 PS-matched cohorts.

Results: 732 patients, 516 without any ICH and 216 with aICH, were included. 418 and 348 patients were identified after matching in the aICH substudy and hemorrhagic infarction type aICH substudy, respectively. In the postmatched population, patients with aICH had worse functional outcomes (mRS score 0-2) at 90 days than patients without any ICH (37.8% vs 55.5%: P<0.001). Worse functional outcomes were seen in patients with aICH who were older (OR=5.59 (95% CI 2.91 to 10.74)), had higher baseline National Institutes of Health Stroke Scale score (OR=6.80 (95% CI 3.72 to 12.43)), lower baseline Alberta Stroke Program Early CT Score (OR=2.08 (95% CI 1.23 to 3.51)), and who received general anesthesia (OR=3.37 (95% CI 1.92 to 5.90)).

Conclusions: This matched-control study largely confirmed that asymptomatic ICH after EVT is associated with worse functional outcomes, and the harmful effect is more significant in older patients and those with severe baseline clinical and radiological features.