Early venous filling following reperfusion therapy in acute ischemic stroke: a systematic review and meta-analysis

Early venous filling (EVF), detected by digital subtraction angiography after endovascular therapy, may indicate hyperperfusion and vascular injury. Emerging evidence suggests that EVF is associated with adverse outcomes and complications, highlighting its potential role as a prognostic imaging marker in acute ischemic stroke (AIS).

A systematic search was conducted in the MEDLINE, Embase, Cochrane Library, and Web of Science databases to identify studies evaluating the outcomes of EVF following reperfusion therapy in cases of AIS. The outcomes included hemorrhagic transformation (HT), parenchymal hematoma (PH), hemorrhagic infarction (HI), symptomatic intracranial hemorrhage (sICH), cerebral infarction as hypodensity on imaging, malignant brain edema (MBE), and unfavorable outcome measured by modified Rankin scale (mRS ≥ 3) after 90 days. A meta-analysis using a random-effects model was conducted to pool the data.

In the data analyses of 12 studies and 2,446 patients, the presence of EVF post-reperfusion was associated with increased risks of HT (odds ratio [OR] = 4.31; 95% confidence interval [CI] [3.00, 6.21]; p < 0.001), PH (OR = 5.73; 95% CI [2.82, 11.65]; p < 0.001), sICH (OR = 6.43; 95% CI [3.49, 8.47]; p < 0.001), cerebral infarction (OR = 15.95; 95% CI [6.37, 39.92]; p < 0.001), MBE (OR = 3.69; 95% CI [2.26, 6.04]; p < 0.001), and unfavorable functional outcomes (OR = 2.58; 95% CI [1.27, 5.23]; p = 0.009).

EVF may serve as a predictor of increased risk of hemorrhagic events, cerebral infarction on imaging, MBE, and unfavorable functional outcomes after brain reperfusion therapy.