ABSTRACT
Objective To assess the cerebrovascular reserve (CVR)and the relationship of CVR with the short-term prognosis in patients with acute atherosclerotic cerebral infarction.Methods A total of 106 patients with unilateral acute (within 72 h) atherosclerotic cerebral infarction (trial group) were selected from December 2016 to December 2017 in the Department of Neurology of the First People's Hospital of Hefei,which were divided into two groups including the lesion group (106 cases) and the nonlesion group (106 cases).The median score of NIHSS in patients was 4(2,5).The control group included 40 healthy controls.The cerebral blood flow reserve and pulsatility index were measured by transcranial Doppler combined with CO2 inhalation test in both the trial group and the control group.According to the rate of change of cerebral blood flow velocity (CBFV),all subjects were divided into two groups including the normal group and the impaired cerebral blood flow reserve group.The changes of CBFV were compared in the control group and the trial group,which was divided into two groups including the group with lesion side and the group with non-lesion side.To evaluate the brain structure reserve the circle of Willis in the trial group was assessed by MRA.According to the integrity of the circle of Willis anterior and posterior circulation all subjects were divided into four groups (type Ⅰ,type Ⅱ,type Ⅲ and type Ⅳ).The effect of the factors,such as diabetes,hypertension,low density lipoprotein (LDL),high density lipoprotein (HDL),smoking,and drinking history,on cerebral blood flow reserve was measured by single-factor analysis.The correlation of NIHSS scores,infarct size and volume with CVR was also measured.All patients in the trial group were treated with drugs and were followed-up for three months.The modified Rankin Scale (Mrs) was used to evaluate the prognosis of the patients.It means poor prognosis if the value of Mrs was more than three.The effects of factors,such as sex,HDL,LDL,diabetes,hypertension,smoking history,drinking history,cerebral blood flow reserve,NIHSS scores,brain structure reserve,infarct location,age,on the prognosis were measured by multivariate Logistic regression.Results The increase rate of CBFV in the lesion-side of patients with atherosclerotic cerebral infarction was 5.94％ (2.18％,10.49％),and the increase rate of pulsatility index was 10.77％ (2.21％,22.62％),which were both lower than the control group (CBFV:11.54％ (5.01％,17.96％),Z =2.547,P＜0.05);pulsatility index:48.36％ (33.93％,64.51％),Z =6.604,P ＜ 0.01).There was significant difference (x2 =4.328,P ＜ 0.05) in the distribution of diabetes,which was 2/14 in the normal group and 43.48％ (40/92) in the impaired cerebral blood flow reserve group.And in the trial group the brain structural reserve was positively correlated to the infarct volume and the NIHSS score,and the rank correlation coefficient was 0.219 and 0.238 respectively (P ＜ 0.05).The prognosis of cerebral blood flow reserve in the normal group was better than the impaired group (x2 =4.155,P ＜ 0.05),for example,the proportion of patients with good prognosis and normal CBFV was 18.84％ (13/69),the proportion of patients with good prognosis but decreased CBFV was 81.16％ (56/69),the proportion of patients with poor prognosis but normal CBFV was 2.70％ (1/37),the proportion of patients with poor prognosis and decreased CBFV was 97.30％ (36/37).The proportion of patients with type Ⅰ and type Ⅲ of the brain structure reserve was 37.68％ (26/69) and 5.80％ (4/69) respectively,whose prognosis was better (x2 =8.456,P ＜ 0.05) than patients with type Ⅱ and type Ⅳ,whose proportion was 43.48％ (30/69) and 13.04％ (9/69).Multivariate Logistic regression analysis showed that NIHSS score,age,and brain structural reserve were risk factors for poor prognosis in the trial group.Normal cerebral blood flow reserve was a protective factor for good prognosis.Conclusions CVR in patients with acute atherosclerotic cerebral infarction is significantly reduced.CVR can be used as an index to evaluate the prognosis of patients who were followed-up for three months.