Predictive Value Of Intraplaque Neovascularization For Ischemic Events In Patients With Mild And Moderate Carotid Artery Stenosis

Background: Intraplaque neovascularization is one of the characteristics of plaque vulnerability,which increases the risk of plaque rupture and ischemic events.However,it is unclear whether intraplaque neovascularization can predict the occurrence of future vascular events（ischemic stroke recurrence and cardiovascular events）.Previous studies on intraplaque neovascularization mainly focused on patients with severe carotid stenosis,while ignoring patients with mild and moderate stenosis.The purpose of this study was to investigate whether intraplaque neovascularization assessed by contrast-enhanced ultrasound is associated with future vascular events in patients with mild and moderate stenosis.Methods: This study is a prospective study.121 patients with recent ischemic stroke hospitalized in the Department of Neurology of the first hospital of Jilin University were recruited.76 patients who met the inclusion and exclusion criteria were finally included in the study.The clinical baseline data,serological indexes and carotid ultrasound parameters were collected.According to the degree of microbubble enhancement assessed by contrast-enhanced ultrasound,the intraplaque neovascularization was divided into grade 0,grade 1 and grade 2.The degree of carotid stenosis can be divided into mild,moderate or severe.During the follow-up period,record whether the patients have ischemic stroke recurrence or cardiovascular events（ischemic events for short）,so as to divide the patients into "recurrence" group and "non-recurrence" group,and determine the prediction model of future vascular events by logistic regression analysis.Results:1.76 patients met the entry criteria with a mean age of 65 ± 7.9 years,and 67（88.2%）were male;after 30±6 months of follow-up,30 patients（39.5%）had an ischemic events and were classified as the "recurrence" group,and the remaining 46 patients were classified as the "non-recurrence" group;2.Clinical baseline data: compared with the "non-recurrence" group,more patients suffered from diabetes mellitus（P=0.007）and fewer patients underwent revascularization（P=0.003）in the "recurrence" group;Serological parameters: cholesterol（P=0.030）,LDL（P=0.042）,and homocysteine（P=0.006）levels were higher in patients in the "recurrence" group than in the "non-recurrence" group;Carotid ultrasound parameters:more patients in the "recurrence" group had carotid plaques that were hypoechoic（P=0.031）and had intraplaque neovascularization grade 2（P= 0.007）;3.Among patients with mild and moderate carotid stenosis,18（42.9%）patients experienced ischemic events during follow-up,whereas among patients with severe carotid stenosis,12（35.3%）patients experienced ischemic events during follow-up;4.In the "recurrence" group,patients with mild and moderate carotid stenosis,10 patients（55%）had intraplaque neovascularization detected as grade 2;In patients with severe carotid stenosis,9 patients（75%）had intraplaque neovascularization grade 2;5.The grade of intraplaque neovascularization was divided into "absence of neovascularization（grade 0）" and "presence of neovascularization（grades 1 and 2）" : sex（P=0.005）,medication adherence（P<0.001）,plaque echogenicity（P=0.003）,and degree of plaque stenosis（P=0.019）were statistically different between the two groups;6.On multivariate logistic regression analysis,intraplaque neovascularization grade 2（odds ratio [OR],6.066;95%confidence interval [CI],1.565–23.512;P=0.009）,diabetes mellitus（OR,6.686;95%CI,1.530–29.221;P=0.012）,homocysteine（OR,1.203;95% CI,1.001–1.446;P=0.049）,Medication adherence（OR,0.218;95% CI,0.055–0.869;P=0.031）was an independent predictor for patients to develop future vascular events.Conclusions: Intraplaque neovascularization detected by contrast-enhanced ultrasound is an independent predictor of future vascular events in patients with recent ischemic stroke,and controlling for risk factors and good medication adherence may reduce the risk of ischemic events.In addition,the high proportion of intraplaque neovascularization grade 2 in patients with mild and moderate stenosis needs more attention.