Cerebral Circulation Time After Thrombectomy: A Potential Predictor of Outcome After Recanalization in Acute Stroke

Abstract

Background Despite successful recanalization, up to half of patients with acute ischemic stroke caused by large-vessel occlusion treated with endovascular treatment (EVT) do not recover to functional independence. We aim to evaluate the role of cerebral circulation time (CCT) as outcome predictor after EVT. Methods and Results We retrospectively enrolled consecutive patients with acute ischemic stroke-large-vessel occlusion undergoing EVT. Three categories of CCT based on digital subtraction angiography were studied: CCT of the stroke side, CCT of the healthy side), and change of CCT of the stroke side versus CCT of the healthy side. Dramatic clinical recovery was defined as a 24-hour National Institutes of Health Stroke Scale score ≤2 or ≥8 points drop. A modified Rankin Scale score ≤2 at 3 months was considered a favorable outcome. Logistic regression analysis was performed to evaluate the prediction of CCT on prognosis. One hundred patients were enrolled, of which 38 (38.0%) experienced a dramatic clinical recovery and 43 (43.0%) achieved a favorable outcome. Logistic regression analysis found that shorter change of CCT of the stroke side versus CCT of the healthy side and CCT of the stroke side were independent positive prognostic factors for dramatic clinical recovery (odds ratio [OR], 0.189; P=0.033; OR, 0.581; P=0.035) and favorable outcomes (OR, 0.142; P=0.020; OR, 0.581; P=0.046) after adjustment for potential confounders. A model including the change of CCT of the stroke side versus CCT of the healthy side also had significantly higher area under the curve values compared with the baseline model in patients with dramatic clinical recovery (0.780 versus 0.742) or favorable outcome (0.759 versus 0.713). Conclusions To our knowledge, this is the first report that CCT based on digital subtraction angiography data exhibits an independent predictive performance for clinical outcome in patients with acute ischemic stroke-large-vessel occlusion after EVT. Given that this readily available CCT can provide alternative perfusion information during EVT, a prospective, multicenter trial is warranted.

Keywords: cerebral circulation time; digital subtraction angiography; endovascular treatment; large‐vessel occlusion; outcome.

Figure 1. Schematic diagram of the measurement of cerebral circulation time (CCT)

(A) Appearance of the siphon segment of internal carotid (yellow arrow); (B) end of the arterial phase (yellow arrow). The CCT was defined as the time from the appearance of the siphon segment of internal carotid (yellow arrow) to the end of the arterial phase during digital subtraction angiography.

Figure 2. A flowchart of subject selection.

EVT indicates endovascular treatment.

Figure 3. Relationship of cerebral circulation time (CCT) to clinical outcome.

(A) No difference is seen in hCCT between DCR (−) and DCR (+) groups and between the mRS 3‐6 and mRS 0‐2 groups, but a significant difference in sCCT between DCR (−) and DCR (+) groups and between the mRS 3‐6 and mRS 0‐2 groups; (B) a significant difference is seen in cCCT between DCR (−) and DCR (+) groups and between the mRS 3‐6 and mRS 0‐2 groups. DCR, dramatic clinical recovery; hCCT indicates CCT of the healthy side; mRS, modified Rankin Scale; and sCCT, CCT of the stroke side.

Figure 4. Receiver operating characteristic curve analysis of different cerebral circulation time (CCT) models for predicting DCR (A) and good outcome (B).

Model 1 adjusted by admission NIHSS, number of passes, collateral score, ICH, and final mTICI. Model 2 adjusted by admission NIHSS, number of passes, collateral score, ICH, final mTICI, and sCCT. Model 3 adjusted by admission NIHSS, number of passes, collateral score, ICH, final mTICI, and cCCT. AUC indicates area under the curve; cCCT, the change of sCCT versus hCCT; CCT, cerebral circulation time; DCR, dramatic clinical recovery; hCCT, CCT of the healthy side; ICH, intracranial hemorrhage; mRS, modified Rankin Scale; mTICI, modified Thrombolysis in Cerebral Infarction; NIHSS, National Institutes of Health Stroke Scale; and sCCT, CCT of the stroke side.

Figure 5. Probability curves for good outcome (mRS 0‐2 at 3 months), stratified according to mTICI versus sCCT (A) or cCCT (B).

cCCT indicates the change of sCCT versus hCCT; CCT, cerebral circulation time; hCCT, cerebral circulation time of the healthy side; mRS, modified Rankin Scale; mTICI, modified Thrombolysis in Cerebral Infarction; and sCCT, cerebral circulation time of the stroke side.