Farhoudi Mehdi, Mehrvar Kaveh, Aslanabadi Naser, Ghabili Kamyar, Baghmishe Nazila Rasi, Ilkhchoei Farzad
Neuroscience Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Vasc Health Risk Manag. 2011;7:203-7. doi: 10.2147/VHRM.S18663. Epub 2011 Mar 31.
Hypercholesterolemia is one of the major modifiable risk factors for atherosclerosis of the coronary and carotid arteries. Although transcranial Doppler (TCD) studies of the cerebral arteries are indicative of decreased cerebral blood flow velocities in patients with hypercholesterolemia, the number of these studies has been limited. The aim of this study was to assess the hemodynamic status of the cerebral arteries in patients with hypercholesterolemia using TCD.
In a case-control study, 60 individuals, including 30 hypercholesterolemic cases (low-density lipoprotein [LDL] > 160 mg/dL) and 30 healthy controls were enrolled. Other arterial risk factors, including diabetes mellitus, hypertension, smoking, and obesity (body mass index > 30), were evaluated and matched as well. TCD was used to assess the hemodynamics of the intracranial arteries as well as the internal carotid arteries. The mean blood flow velocity, pulsatility index, and resistance index were recorded in all the arteries.
The mean blood flow velocity, pulsatility index, and resistance index of the intracranial arteries and internal carotid arteries were not significantly different between the two groups (P > 0.05). However, those with higher levels of LDL (>180 mg/dL) showed significantly lower mean blood flow velocity and resistance index of the internal carotid arteries than the healthy controls. In addition, individuals with high-density lipoprotein (HDL) <35 mg/dL had significantly lower mean blood flow velocity in the internal carotid arteries.
Hypercholesterolemia (LDL >160 mg/dL) does not seem to have a detrimental effect on the hemodynamic status of the intracranial arteries and internal carotid arteries. However, in cases of higher LDL (>180 mg/dL) and lower HDL, decreased TCD parameters in the internal carotid arteries, as a surrogate of the peripheral arteries, are prominent.
高胆固醇血症是冠状动脉和颈动脉动脉粥样硬化的主要可改变危险因素之一。尽管经颅多普勒（TCD）对脑动脉的研究表明高胆固醇血症患者的脑血流速度降低，但此类研究数量有限。本研究的目的是使用TCD评估高胆固醇血症患者脑动脉的血流动力学状态。
在一项病例对照研究中，纳入了60名个体，包括30例高胆固醇血症患者（低密度脂蛋白[LDL]>160mg/dL）和30名健康对照者。还评估并匹配了其他动脉危险因素，包括糖尿病、高血压、吸烟和肥胖（体重指数>30）。使用TCD评估颅内动脉以及颈内动脉的血流动力学。记录所有动脉的平均血流速度、搏动指数和阻力指数。
两组颅内动脉和颈内动脉的平均血流速度、搏动指数和阻力指数无显著差异（P>0.05）。然而，LDL水平较高（>180mg/dL）的患者颈内动脉的平均血流速度和阻力指数显著低于健康对照者。此外，高密度脂蛋白（HDL）<35mg/dL的个体颈内动脉的平均血流速度显著较低。
高胆固醇血症（LDL>160mg/dL）似乎对颅内动脉和颈内动脉的血流动力学状态没有不利影响。然而，在LDL较高（>180mg/dL）和HDL较低的情况下，作为外周动脉替代指标的颈内动脉TCD参数降低较为明显。
