| Objective:Hemodynamics plays an important role in the risk and pathogenesis of ischemic stroke in patients with atherosclerotic stenosis of large intra-and extra-cranial arteries,but there is no standardized method for the assessment of cerebral hemodynamics.The aim of this study was to investigate the value of quantitative flow ratio(QFR)in assessing cerebral hemodynamic status before and after endovascular treatment in selected patients and to determine the correlation between QFR and the occurrence,severity of ischemic stroke events and short-term prognosis.Methods:Patients who received elective endovascular treatment for severe intra-and extracranial large artery atherosclerotic stenosis in the Department of Neurology of the First People’s Hospital from January 2020 to September 2022 were enrolled in this study.Demographic,vascular risk factors,laboratory test results,and digital subtraction angiography(DSA)images were collected retrospectively.Murray’s law-based QFR was used to analyze DSA images and calculate the QFR before and after endovascular treatment.Based on cardiology and previous studies of cerebrovascular pressure ratios measured by pressure guidewire,this study empirically delineated 0.8,0.75,and 0.7 as the cut-off values for preoperative QFR.Statistical analysis was performed to correlate baseline data,preoperative and postoperative QFR with baseline modified Rankin Scale(m RS)scores evaluating stroke severity and 90-day post-discharge m RS scores evaluating short-term prognosis.Results:A total of 63 patients with severe intra-and extra-cranial large artery atherosclerotic stenosis were included in this study,55 of whom were patients with symptomatic intracranial atherosclerotic stenosis and symptomatic extracranial internal carotid artery(ICA)stenosis and 8 with asymptomatic extracranial ICA stenosis.48(76.2%)patients had a preoperative QFR below 0.8,which was more significantly hemodynamically impaired than in the remaining patients.Preoperative QFR at a cutoff value of 0.8(OR,28.376;95% CI,1.24-650.65;P=0.036)was an independent predictor of whether patients in this study cohort developed symptomatic cerebrovascular events before endovascular treatment.In the ICA-related symptomatic cerebrovascular events subgroup,preoperative QFR(OR,0.005;95% CI,0-0.84;P=0.043)was an independent predictor of short-term prognosis.Among the baseline characteristics,baseline NIHSS score,history of alcohol consumption,and white blood cell count were independently associated with stroke severity or short-term prognosis.Conclusion:This study demonstrated the feasibility of QFR in assessing the cerebral hemodynamic status of patients with atherosclerotic stenosis of intra-and extra-cranial large arteries.Preoperative QFR with a cut-off value of 0.8 was an independent predictor of whether symptomatic cerebrovascular events occurred before endovascular treatment in this study cohort,and patients with QFR below 0.8 may have a greater risk of ischemic stroke events.In the subgroup of ICA-related symptomatic cerebrovascular events,a higher preoperative QFR was independently associated with a favorable shortterm prognosis.These findings suggest that QFR may help to identify patients at higher risk of ischemic stroke or with poorer short-term prognosis,thus enabling risk grading of patients and better selection of treatment options. |
