DSA-based Postoperative Venous Outflow Serves as a Potential Prognostic Surrogate for Cerebral Microcirculation Time After Recanalization in Acute Ischemic Stroke.

RATIONALE AND OBJECTIVES: Successful recanalization fundamentally reshapes cerebral hemodynamics in acute ischemic stroke (AIS), making preprocedural hemodynamic biomarkers alone inadequate. We assessed postoperative venous outflow (PVO) based on digital subtraction angiography (DSA) and explored its prognostic role. MATERIALS AND METHODS: This retrospective cohort study included AIS patients who achieved recanalization. All patients underwent standard cerebral DSA immediately after successful recanalization. We assessed the microvascular cerebral circulation time (mCCT) and cortical vein opacification score (COVES) based on DSA. The primary outcome was functional independence at 90 days, defined as a modified Rankin Scale score of 0 to 2. Logistic regression and receiver operating characteristic (ROC) analysis were used. RESULTS: 156 patients were included (median age 69 years and 44.2% men). ROC curve analysis determined the optimal cut-off of 4 for COVES dichotomization. Multivariate analysis showed that the favorable PVO (COVES ≥ 4) was significantly associated with functional independence at 90 days (adjusted odds ratio 10.55, 95% confidence interval 3.86-28.88, p < 0.001). After incorporating PVO into the conventional model, the area under the receiver operating characteristic curve increased significantly (0.882 vs. 0.816, p = 0.008, DeLong test) and was not inferior to the mCCT model (0.882 vs. 0.860, p = 0.210). Finally, the PVO model demonstrated good discrimination and calibration, confirmed by fivefold cross-validation. CONCLUSION: The DSA-based PVO after successful recanalization is an effective and practical prognostic surrogate for functional outcomes in AIS, providing predictive value for 90-day functional outcomes comparable to the more complex mCCT.