Subcortical infarcts on admission CTP predict poor outcome despite excellent reperfusion in delayed time windows

The effect of pretreatment infarct location on clinical outcome after successful mechanical thrombectomy is not understood. Our aim was to evaluate the association between computed tomography perfusion (CTP)-based ischemic core location and clinical outcome following excellent reperfusion in late time windows.

We retrospectively reviewed patients who underwent thrombectomy for acute anterior circulation large vessel occlusion in late time windows from October 2019 to June 2021 and enrolled 65 patients with visible ischemic core on admission CTP who had received excellent reperfusion (modified thrombolysis in cerebral infarction grade 2c/3). Poor outcome was defined as a modified Rankin scale score of 3-6 at 90 days. The ischemic core infarct territories were classified into the cortical and subcortical areas. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were used in this study.

Of the 65 patients analyzed, 38 (58.5%) had a poor outcome. Multivariable logistic analysis showed that the subcortical infarcts (OR 11.75; 95% CI 1.79-77.32; P = 0.010) and their volume (OR 1.17; 95% CI 1.04-1.32; P = 0.011) were independently associated with poor outcome. The ROC curve indicated the capacity of the subcortical infarct involvement (areas under the curve (AUC) = 0.65; 95% CI, 0.53-0.77, P < 0.001) and subcortical infarct volume (AUC = 0.72; 95% CI, 0.60-0.83, P < 0.001) in predicting poor outcome accurately.

Subcortical infarcts and their volume on admission CTP are associated with poor outcome after excellent reperfusion in late time windows, rather than cortical infarcts.