The Influences And Clinical Values About The Variation Of Plasma Level Of Von Wellibrand Factor Of Patients With Acute Ischemic Stroke After Interventional Therapy

BackgroundAtherosclerotic stenosis,a risk factor for recurrent stroke,often occurs in patients with acute ischemic stroke(AIS).PTAS or interventional therapy,a method about treatment as well recurrence prevention for AIS,has been recognized for its clinical efficacy,especially for patients with severe arterial stenosis.However,the stent stimulates or damages the vascular endothelium in some degree and results in the complications of vascular stenosis and thrombus formation near the stent,which can ultimately affect the patient’s clinical prognosis..Therefore,it is of great clinical significance to explore effective monitoring indicators,such as von Willebrand Factor,before and after the interventional therapy.Synthesized by vascular endothelial cells,von Willebrand Factor(vWF),as the marker of endothelial injury,mediates the adhesion between platelets and hemal wall and promote the early formation of blood clots when endothelial injury or atheromatous plaque rupture resulting in subcutaneous collagen exposed.Nowadays there are few studies on the factors influencing the variation of vWF level after interventional therapy in patients with AIS.Previous studies have confirmed the damage of stent to vascular endothelium and explored the correlation between the preoperative stenosis of lesion vessels,the number of stents and the variation of vWF levels.However,these studies also have certain limitations:1)The influence of stent properties and operation parameters on the change of vWF level was not explored.2)Patients were included in these studies with different time after onset of stroke and were not limited to patients with AIS.3)there are no studies about whether the complications of interventional therapy for patients with AIS and the clinical prognosis are related to the variation of plasma level of vWF.Our study attempts to use vWF as the main test index to determine the influences about variation of vWF level of patients with AIS after the interventional therapy,and to explore the relationship between this variation and clinical prognosis.Purpose1.To eplain the influences about the variation of plasma level of von Wellibrand Factor of patients with acute ischemic stroke after interventional therapy.2.Besides,to explore the relationshiops between the vWF level variation and clinical prognosis.Method1.Subjects:This study involved 82 patients with AIS,who were admitted in Neurology Department of Southern Hospital between February 2016 and December 2017 and underwent only DSA(Digital Subtraction Angiography,n=37)or PTAS(interventional therapy,n=45).All cases,with at least one atherosclerosis risk factor,were strictly adhered to inclusion standards and exclusion criterias,and must completed DSA in 14 days after onset of stroke.2.Groups:(1)Case Groups:The case groups were divided into DSA group and Stent group(which underwent interventional therapy)according to the pattern of the surgical approach.(2)Stent subgroups were divided into:①According to whether the degree of preoperative stenosis of lesion vessels was more than 70%:severe stenosis group and non-severe stricture group.②According to the number of stents:single stent group(1 stent)and double stents group(2 stents).③According to whether the variation quantity of the plasma level of vWF after interventional therapy(postoperative level simus preoperative level)was greater than the median of 33.06 ng/ml:vWF significantly increased group(n = 25)and non-significantly increased group(n = 20).(3)The cases who underwent single stent implantation were divided into single Stent subgroups:①According to location of the stent:anterior circulation group(internal carotid system)and posterior circulation group(vertebrobasilar artery system).②According to balloon maximum inflation pressure(atm):no inflation group,≤8atm and>8atm group.③According to balloon inflation frequency:no inflation group,once and twice group.3.On the same day and next day of procedure,venous blood was extracted to detect the vWF level of the patients before and after the procedure in the morning,and the clinical data of the patients were recorded.4.Statistical analysis:The statistical analysis was executed by SPSS20.0 sofeware,using t-test,Chi-squared test and Non-parametric rank and test for statistical.P<0.05 was considered to be statistically significant.Results1.The change of plasma level of vWF was not significantly observed after DSA compared with before DSA.Plasma level of vWF significantly increased by 33.06(41.32)ng/ml after interventional therapy compared with before procedure.There is no significance of plasma vWF level between DSA group and Stent group before the procedure,while Stent group has higher vWF level after the procedure.The variation quantity of the plasma level of vWF after interventional therapy was significantly higher than the DSA group.2.Among the subgroups,the plasma level of vWF before the interventional therapy between severe stenosis group and non-severe stricture group showed no significant deviation,while the former had significantly higher vWF level than the latter.Both groups had no significant deviation in the variation quantity of the plasma level of vWF.Double stents group had greater variation quantity than single stent group,while the plasma level of vWF before or after the interventional therapy between both groups showed no significant deviation.3.Among the single stent subgroups,the change of plasma level of vWF was not significantly observed before and after interventional therapy between different locations of the stent,balloon maximum inflation pressure and balloon inflation frequency subgroups.4.There is no significant deviation of the odds of neuroworsening and long-term prognosis between vWF significantly increased group and non-significantly increased group.Conclusions1.The plasma level of vWF of patients with AIS was significantly increased after the interventional therapy,which confirmed that the stent caused a certain degree of damage to the endothelium,and the extent of injury was greater than that of purely DSA procedure.2.For patients with acute ischemic stroke,the more severe the stenosis of the preoperative lesion and the more stents are placed,the more damage to the endothelium caused by stents as well as the higher the plasma vWF level after the interventional therapy is.3.More evidence is required to determine whether the variation in plasma level of vWF could predict acute and long-term outcomes of acute ischemic stroke after interventional therapy.