Characteristic Analysis Of Dynamic Cerebral Autoregulation In Patients With Acute Ischemic Stroke

Background and objective:Dynamic cerebral autoregulation(dCA)is a self-protective mechanism that keeps cerebral blood volume stable despite arterial blood pressure(ABP)fluctuating.DCA is probably impaired in the acute and even subacute phases after acute ischemic stroke(AIS).However,the relationship between relevant clinical factors and dCA after AIS has not been investigated.The purpose of this study is to explore the relationship between dCA and clinical factors and prognosis,to investigate the characteristics of dCA in AIS patients,and to provide theoretical basis for individualized treatment in AIS patients.Methods:Patients diagnosed with AIS within 3 days from symptom onset were recruited consecutively from the Department of Neurology,First Hospital of Jilin University between September 2016 and August 2018.Data of 60 age-and sex-matched healthy volunteers were obtained as a reference value of dCA.Serial measurements were performed on 0?3 days(measurement 1)and 7?10 days(measurement 2)after the onset.Middle cerebral artery blood flow velocities and simultaneous ABP were recorded continuously with transcranial Doppler ultrasound combined with a servo-controlled finger plethysmograph.Transfer function analysis was used to derive dCA parameters:phase difference and coherence.The relationship between phase difference and clinical factors and prognosis was discussed through statistical analysis.Results:Bilateral phase difference was significantly lower(indicating impaired dCA)in AIS patients,both in measurement 1 and measurement 2 when compared with those of healthy controls(all P<0.001).The ipsilateral phase difference in measurement 2 was significantly lower than in measurement 1,indicating the deterioration of the dCA function(P=0.002).In the multivariate regression analysis,increased age was a significant independent predictor of bilateral disturbed phase difference in measurement 1 and measurement 2(measurement 1:ipsilateral:?=-0.198,P=0.010,contralateral:?=-0.217,P=0.009;measurement 2:ipsilateral:?=-0.253,P=0.003,contralateral:?=-0.284,P=0.001).History of hypertension(?=-0.176,P=0.023),history of diabetes(?=-0.202,P=0.009),higher creatinine(?=-0.155,P=0.045)were significant independent predictors of disturbed ipsilateral phase difference in measurement 1.Higher triglyceride(?=-0.23 5,P=0.007)was a significant independent predictor of disturbed ipsilateral phase difference in measurement 2.Intravenous thrombolysis was a significant independent predictor of relatively preserved phase difference in measurement 2(ipsilateral:?=0.198,P=0.025,contralateral:?=0.202,P=0.026).Compared to subtype of small artery occlusion,subtype of large-artery atherosclerosis was a significant independent predictor of reduced ipsilateral phase difference in measurement 1 and measurement 2(measurement 1:?=-0.326,P<0.001,measurement 2:?=-0.274,P=0.002).After adjusting for related clinical factors,ipsilateral phase difference>30.600 in measurement 1 was an independent predictor of good clinical outcomes(adjusted OR=3.40,95%CI:1.28-9.04,P=0.014)Conclusions:DCA was sustained to be bilaterally impaired in the acute and even subacute phase after AIS.Increased age,history of hypertension,history of diabetes,higher creatinine,higher triglyceride and subtype of large-artery atherosclerosis were related to disturbed autoregulation after AIS.Patients who receiving thrombolysis tended to have relatively preserved dCA in the subacute phase.Ipsilateral phase>30.60° in measurement 1 was an independent predictor of good clinical outcomes.