Abstract:

Objective　To evaluate the cerebrovascular function and intervene with risk factors in asymptomatic patients with moderate to severe carotid artery stenosis in Liwan community, and to explore the relationship between change in cerebrovascular reserve capacity and cerebrovascular events in asymptomatic patients with moderate to severe carotid artery stenosis. Methods　It was a prospective study. A total of 2 315 chronic disease patients were screened from Liwan District, Guangzhou City from January 2020 to December 2021, including 262 asymptomatic patients with moderate to severe carotid artery stenosis (175 patients with moderate stenosis and 87 patients with severe stenosis). Among them, 5 asymptomatic patients with severe carotid artery stenosis were referred to the neurointerventional department for carotid artery surgery, and the other 257 asymptomatic patients with moderate to severe carotid artery stenosis [153 males and 104 females, aged (75.08±2.88) years] were enrolled. The enrolled patients undergo cerebrovascular function assessment, risk factor intervention, antiplatelet aggregation, and lipid-lowering treatment. The change of cerebrovascular reserve capacity and incidence of cerebral ischemic events were recorded one year later. t test and χ² test were used. Results　A total of 4 asymptomatic patients with moderate to severe carotid artery stenosis had ischemic events, with an incidence of 1.5% (4/257) in the next year. The age [(78.50±2.88) years old], smoking rate [100.0% (4/4)], and prevalence rate of hyperlipidemia [100.0% (4/4)] in the patients with cerebral ischemic events were higher than those in the patients without cerebral ischemic events [(75.02±2.85) years old, 44.3% (112/253), and 45.5% (115/253)], with statistically significant differences (t=2.413, χ²=4.939 and 4.712; all P<0.05). The cerebrovascular reserve capacity at enrollment [(17.09±0.69)%], the cerebrovascular reserve capacity 1 year after enrollment [(17.89±0.37)%], and the increase of cerebrovascular reserve capacity [(0.80±0.57)%] of the patients with cerebral ischemic events were lower than those of the patients without cerebral ischemic events [(21.99±2.04)%, (25.38±2.02)%, and (3.39±2.15)%], with statistically significant differences (t=4.790, 7.372, and 2.397, all P<0.05). The proportion of males [69.5% (57/82)], smoking rate [54.9% (45/82)], diabetes rate [51.2% (42/82)], age [(76.58±2.03) years old], and low density lipoprotein [(4.11±0.71)mmol/L] in the asymptomatic patients with severe carotid artery stenosis were all higher than those in the asymptomatic patients with moderate carotid artery stenosis [54.9% (96/175), 40.6% (71/175), 37.1% (65/175), (74.37±2.95) years old, and (3.55±1.07)mmol/L], with statistically significant differences (χ²=4.978, 4.615, and 4.553, t=6.118 and 4.264; all P<0.05). After 1 year of treatment, the increase of cerebrovascular reserve capacity in the moderate stenosis group [(3.68±2.25)%] was significantly higher than that in the severe stenosis group [(2.64±1.74)%], with a statistically significant difference (t=3.689, P<0.05). At enrollment and 1 year later, the mean blood flow velocity before CO₂ inhalation, the mean blood flow velocity after CO₂ inhalation, and the cerebrovascular reserve capacity in the moderate stenosis group were higher than those in the severe stenosis group [(64.68±3.42) cm/s vs. (60.76±5.19) cm/s, (79.21±4.78) cm/s vs. (73.40±6.09) cm/s, (22.43±2.08)% vs. (20.80±1.72)%, (65.41±3.05) cm/s vs. (60.86±3.86) cm/s, (82.50±4.16) cm/s vs. (75.12±4.62) cm/s, (26.12±1.95)% vs. (23.44±1.54)%], with statistically significant differences (t=7.173, 8.294, 6.185, 10.201, 12.799, and 10.925, all P<0.05). Conclusions　There is a correlation between change in cerebrovascular reserve capacity and the risk of ischemic events in asymptomatic patients with moderate to severe carotid artery stenosis. Improving cerebrovascular reserve capacity through primary prevention can reduce the occurrence of cerebrovascular events.

Key words:

Cerebral infarction, Asymptomatic carotid artery stenosis, Risk factors, Cerebrovascular reserve capacity

摘要：

目的　对荔湾社区无症状中重度颈动脉狭窄患者进行脑血管功能评估及危险因素干预，探讨无症状中重度颈动脉狭窄患者脑血管储备能力变化与脑血管事件的关系。方法　本文为前瞻性研究。选取2020年1月至2021年12月广州市荔湾社区中慢性病患者2 315例，其中无症状中重度颈动脉狭窄患者262例［中度狭窄175例、重度狭窄87例］，有5例无症状重度颈动脉狭窄患者考虑颈动脉手术转诊到神经介入科，余257例［男153例、女104例，年龄（75.08±2.88）岁］无症状中重度颈动脉狭窄患者入组观察。入组患者均进行脑血管功能评估、危险因素干预、抗血小板聚集及降脂治疗。记录1年后患者脑血管储备能力变化及脑缺血事件发病率。采用t检验、χ²检验。结果　入组无症状中重度颈动脉狭窄患者共有4例发生缺血性事件，次年发病率为1.5%（4/257）。出现脑缺血事件患者年龄［（78.50±2.88）岁］、吸烟率［100.0%（4/4）］、高脂血症患病率［100.0%（4/4）］均高于无脑缺血事件患者［（75.02±2.85）岁、44.3%（112/253）、45.5%（115/253）］，差异均有统计学意义（t=2.413，χ²=4.939、4.712；均P<0.05）。出现脑缺血事件患者入组时脑血管储备能力［（17.09±0.69）%］、入组1年后脑血管储备能力［（17.89±0.37）%］及脑血管储备能力增加值［（0.80±0.57）%］均低于无脑缺血事件患者［（21.99±2.04）%、（25.38±2.02）%、（3.39±2.15）%］，差异均有统计学意义（t=4.790、7.372、2.397，均P<0.05）。无症状重度颈动脉狭窄患者男性比例［69.5%（57/82）］、吸烟率［54.9%（45/82）］、糖尿病患病率［51.2%（42/82）］、年龄［（76.58±2.03）岁］、低密度脂蛋白［（4.11±0.71）mmol/L］均高于无症状中度颈动脉狭窄患者［54.9%（96/175）、40.6%（71/175）、37.1%（65/175）、（74.37±2.95）岁、（3.55±1.07）mmol/L］，差异均有统计学意义（χ²=4.978、4.615、4.553，t=6.118、4.264；均P<0.05）。治疗1年后，中度狭窄组患者脑血管储备能力增加值［（3.68±2.25）%］显著高于重度狭窄组［（2.64±1.74）%］，差异有统计学意义（t=3.689，P<0.05）。入组时及1年后，中度狭窄组患者吸入CO₂前血流平均速度、吸入CO₂后血流平均速度、脑血管储备能力均高于重度狭窄组［（64.68±3.42）cm/s比（60.76±5.19）cm/s、（79.21±4.78）cm/s比（73.40±6.09）cm/s、（22.43±2.08）%比（20.80±1.72）%、（65.41±3.05）cm/s比（60.86±3.86）cm/s、（82.50±4.16）cm/s比（75.12±4.62）cm/s、（26.12±1.95）%比（23.44±1.54）%］，差异均有统计学意义（t=7.173、8.294、6.185、10.201、12.799、10.925，均P<0.05）。结论　脑血管储备能力改变与无症状中重度颈动脉狭窄患者发生缺血性事件风险之间相关。通过一级预防来改善脑血管储备能力，可以减少脑血管事件发生。

关键词:

脑梗死, 无症状颈动脉狭窄, 危险因素, 脑血管储备能力