Lee Min Y, Wu Chan M, Yu Kuo H, Chu Chih S, Lee Kun T, Sheu Sheng H, Lai Wen T
Division of Cardiology, Department of Internal Medicine, Kaohsiung Municipal United Hospital, Kaohsiung, Taiwan.
Am J Hypertens. 2008 Jul;21(7):765-70. doi: 10.1038/ajh.2008.182. Epub 2008 May 1.
Carotid intima-media thickness (IMT) and plaque burden evaluated by B-mode ultrasound have been used as relevant indicators for carotid atherosclerosis. This study was aimed to investigate the relationship between hemodynamic parameters in the common carotid artery (CCA) and the severity of carotid atherosclerosis in untreated hypertensive patients.
Carotid IMT and plaque burden were evaluated in bilateral CCA, bifurcations, external and internal carotid arteries using duplex ultrasound in 80 untreated hypertensive patients. The patients were divided into four groups according to plaque burden. Hemodynamic parameters of CCA, including peak and mean circumferential wall tension (CWT), tensile stress (TS), wall shear stress (WSS), and Young's elastic modulus (YEM), were calculated after measurements of internal diameter (ID), IMT, and peak and mean flow velocities of CCA. Arterial stiffness was also assessed using the brachial-ankle pulse wave velocity (baPWV).
Age, pulse pressure, creatinine, carotid IMT, and mean TS were shown to have significant differences among the four plaque groups (P < 0.05). Peak CWT and peak TS were also shown to have marginal differences. In univariate analysis, the peak and mean CWT and TS were significantly correlated with plaque score. Stepwise multiple regression analysis showed that carotid IMT, age, and peak CWT were independently associated with plaque score.
These results suggest that the CWT and TS of the CCA are associated with the severity of carotid atherosclerosis in untreated hypertensive patients. Hence, the hemodynamics of vessels may contribute to the plaque burden of low-resistance arteries.
通过B型超声评估的颈动脉内膜中层厚度（IMT）和斑块负荷已被用作颈动脉粥样硬化的相关指标。本研究旨在探讨未经治疗的高血压患者颈总动脉（CCA）血流动力学参数与颈动脉粥样硬化严重程度之间的关系。
使用双功超声对80例未经治疗的高血压患者双侧CCA、分叉处、颈外动脉和颈内动脉的IMT和斑块负荷进行评估。根据斑块负荷将患者分为四组。在测量CCA内径（ID）、IMT以及峰值和平均流速后，计算CCA的血流动力学参数，包括峰值和平均圆周壁张力（CWT）、拉应力（TS）、壁面切应力（WSS）和杨氏弹性模量（YEM）。还使用臂踝脉搏波速度（baPWV）评估动脉僵硬度。
年龄、脉压、肌酐、颈动脉IMT和平均TS在四个斑块组之间存在显著差异（P<0.05）。峰值CWT和峰值TS也显示出边缘差异。在单因素分析中，峰值和平均CWT以及TS与斑块评分显著相关。逐步多元回归分析表明，颈动脉IMT、年龄和峰值CWT与斑块评分独立相关。
这些结果表明，未经治疗的高血压患者CCA的CWT和TS与颈动脉粥样硬化的严重程度相关。因此，血管的血流动力学可能导致低阻力动脉的斑块负荷。
