Predictors for recurrent ischemic stroke in patients with watershed infarct induced by intracranial artery stenosis

Background and purpose: Symptomatic intracranial artery stenosis (sICAS) is strongly associated with an elevated risk of recurrent ischemic stroke, yet the underlying risk factors remain elusive. In this present study, we aimed to investigate the risk factors and predictive value of imaging features for recurrent ischemic stroke in patients with watershed infarction caused by ICAS. Methods: We prospectively collected clinical information and imaging data from patients with watershed infarction caused by ICAS. The primary outcome was recurrent ischemic cerebrovascular events in the same territory within 1 year. The original magnetic resonance images (MRI) were post-processed by the Fast-processing of ischemic stroke (F-Stroke) software to compute the perfusion parameters. The assessment of white matter hyperintensity (WMH) was performed in accordance with the Fazekas scale. Binary logistic regression analysis was performed to explore the association of imaging characteristics and recurrent ischemic stroke. Subsequently, we performed ROC curve analyses to determine their discriminatory capacity for ischemic stroke recurrence. Results: A total of 139 patients were successfully enrolled in the present study. The recurrence rate in the total population was 18.71 %. Compared with patients without recurrent ischemic stroke, those who experienced recurrence had a higher proportion of prior ischemic stroke history (25.66 % vs. 53.85 %) and severe WMH (30.77 % vs. 7.97 %), as well as higher baseline NIHSS scores and volume of Tmax > 4 s. Logistic regression analysis revealed that both the volume of Tmax > 4 s and severe WMH significantly influenced the risk of recurrent ischemic stroke occurrence. Furthermore, ROC curve analyses demonstrated that the discriminatory capacity of the volume of Tmax > 4 s (AUC = 0.64, 95 %CI = 0.51-0.77, P = 0.029) was marginally superior to WMH scores (AUC = 0.62, 95 %CI = 0.49-0.75, P = 0.066). Whereas, the combination of the volume of Tmax > 4 s and the WMH scores showed better discriminatory capacity (AUC = 0.73, 95 %CI = 0.61-0.85, P < 0.001). Conclusion: MR-guiding cerebral hypoperfusion and severe WMH is susceptible to recurrence of ischemic stroke, thereby serving as valuable predictors for recurrence in patients with watershed infarction caused by ICAS.