超声评价非对称性颈动脉粥样硬化斑块与血流剪切力的关系

目的 对比非对称性颈动脉粥样硬化患者斑块侧与无斑块侧的颈总动脉血流剪切力，分析血流剪切力与颈动脉粥样硬化斑块的关系。方法 利用彩色多普勒超声测量78名无症状性单侧颈动脉斑块患者的双侧颈总动脉舒张末期内径（internal diameter，ID）、收缩末期峰值流速（peak systolic velocity，Vp）及内-中膜厚度（intima-media thickness，IMT），并根据公式计算最大血流剪切力（τm）=4μVp/ID（μ为血液黏滞度），对比分析双侧τm及IMT的差异，并通过直线相关分析分析τm与IMT的关系。结果 斑块侧颈总动脉ID大于无斑块侧（6.7±0.9mm vs 6.1±0.8mm，P <0.01）；斑块侧颈总动脉IMT厚于无斑块侧（1.3±0.2mm vs 0.8±0.1mm，P <0.01）；斑块侧颈总动脉τm低于无斑块侧（18±5dynes・cm-2 vs 23±9dynes・cm-2，P <0.01）。IMT与τm呈负相关。结论 非对称性颈动脉粥样硬化患者的双侧颈动脉血流剪切力存在差异，斑块侧血流剪切力明显低于无斑块侧，且减低的血流剪切力与IMT呈负相关，进一步证实低血流剪切力与颈动脉粥样硬化斑块的关系。

Evaluate the Relationship between Asymmetrical Carotid Arteriosclerosis and Wall Shear Stress by Ultrasound

Objective To evaluate wall shear stress in both sides of asymmetrical carotid atherosclerosis patients, and analyze the relationship between wall shear stress and carotid atherosclerosis.Methods 78 participants screened by doppler ultrasound examination who presented unilateralplaque were enrolled. Internal diameter(ID), peak systolic velocity(Vp), and intima-media thickness (IMT) of common carotid were measured by doppler ultrasound independently.. Evaluate the difference of τ m and IMT between the carotids with and without atherosclerotic lesions,andanalyze the relationship between τ m and IMT by linear correlation analysis.Results ID is larger in the side with atherosclerotic lesions than in the side without lesions(6.7±0.9mm vs 6.1±0.8mm, P <0.01). IMT is thicker in the side with atherosclerotic lesions than in the side without lesions(1.3±0.2mm vs 0.8±0.1mm, P <0.01). τ m is lower in the side with atherosclerotic lesions than in the side without lesions(18±5 dynes·cm-2 vs 23±9 dynes·cm-2,P <0.01.) IMT is negatively correlated with τm.Conclusion In asymmetrical carotid atherosclerosis, wall shear stress is different between the different sides, which is lower in the carotid arteries where plaques are present than in plaque-free arteries obviously. The wall shear stress is negatively correlated with IMT. These findings providein vivo evidence for a association between wall shear stress and atherosclerotic lesions.