Asymptomatic Intracerebral Hemorrhage Following Endovascular Stroke Therapy Is Not Benign: A Systematic Review and Meta-Analysis.

BACKGROUND:Asymptomatic intracerebral hemorrhage (aICH) occurs in approximately 35% of patients with acute ischemic stroke after endovascular thrombectomy. Unlike symptomatic ICH, studies evaluating the effect of aICH on outcomes have been inconclusive. We performed a systematic review and meta-analysis to evaluate the long-term effects of postendovascular thrombectomy aICH. METHODS AND RESULTS:The meta-analysis protocol was submitted to the International Prospective Register of Systematic Reviews a priori. PubMed, Scopus, and Web of Science were searched from inception through September 2023, yielding 312 studies. Two authors independently reviewed all abstracts. Included studies contained adult patients with ischemic stroke undergoing endovascular thrombectomy with follow-up imaging assessment of ICH reporting comparative outcomes according to aICH versus no ICH. After screening, 60 papers were fully reviewed, and 10 studies fulfilled inclusion criteria (n=5723 patients total, 1932 with aICH). Meta-analysis was performed using Cochrane RevMan v5.4. Effects were estimated by a random-effects model to estimate summary odds ratio (OR) of the effect of aICH versus no ICH on primary outcomes of 90-day modified Rankin Scale 3 to 6 and mortality. The presence of aICH was associated with a higher odds of 90-day mRS 3 to 6 (OR, 2.17 [95% CI, 1.81-2.60], P<0.0001, I2 46% Q 19.15) and mortality (OR, 1.72 [95% CI, 1.17-2.53], P:0.005, I2 79% Q 27.59) compared with no ICH. This difference was maintained following subgroup analysis according to hemorrhage classification and recanalization status. CONCLUSIONS:The presence of aICH is associated with worse 90-day functional outcomes and higher mortality. Further studies to evaluate the factors predicting aICH and treatments aimed at reducing its occurrence are warranted.