老年高血压患者颈动脉血流动力学变化的超声特征

背景血管超声检查动脉管壁的中内膜厚度及粥样斑块与病理学方法相关良好. 目的应用超声方法观察老年高血压患者的颈总动脉和颈内动脉的血流动力学变化,并评价脉压、左室质量指数、血管的阻力指数、切率之间的相互关系. 设计随机对照,相关分析实验. 单位江苏大学附属医院超声科. 对象选择2000-09-30/2002-03-30江苏大学附属医院超声科入选老年高血压患者54例,男33例,女21例.同期在本院超声科检查的正常血压(收缩压＜130 mm Hg和/或舒张压＜85 mm Hg)者为对照组26例,男16例,女10例. 方法彩色多普勒血流显像技术检查每例患者左室腔舒张末内径,室间隔与左室后壁的舒张末厚度,计算左室质量指数.检查双侧颈总动脉和颈内动脉的内径、中内膜厚度和收缩期血流最大峰值流速及阻力指数,计算血管的切率和斑块指数,对动脉压、左室质量指数与阻力指数和切率作线性相关分析,并与同期对照组比较. 主要观察指标①两组受检对象脉压、左室质量指数和颈总动脉斑块指数.②双侧颈总动脉和颈内动脉的内径、中内膜厚度和收缩期血流最大峰值流速及阻力指数,计算斑块指数及最大切率. 结果80例对象均进入结果分析.①老年高血压组脉压,左室质量指数,斑块发生率和斑块指数明显大于对照组(64.36±7.44)mm Hg,(45.78±8.72)mm Hg;(131.47±18.73)g/m2,(83.28±12.34)g/m2;5.62±1.78,3.44±1.10;66.7%,23.1%,(x213.37,t=5.730-13.234,P＜0.01)].②老年高血压组颈总动脉和颈内动脉的内径、中内膜厚度、阻力指数明显高于对照组颈总动脉(8.96±1.20)mm,(8.08±0.96)mm;(1.28±0.88)mm,(0.91±0.17)mm;0.75±0.05,0.69±0.06.颈内动脉(6.82±1.12)mm,(5.72±0.92)mm;(1.06±0.17) mm,(0.76±0.15)mm;0.70±0.07,0.64±0.06,t=2.872～10.850,P＜0.01],收缩期血流最大峰值流速和切率明显低于对照组颈总动脉(47.44±12.85)cm/s,(60.20±14.32)cm/s;(225.78±95.76)/s,(300.26±110.42)/s.颈内动脉(41.22±10.18)cm/s,(48.64±11.58)cm/s;(268.54±112.56)/s,(324.52±121.42)/s,t=2.872～10.850,P＜0.01].③老年高血压患者的脉压,左室质量指数及颈总动脉和颈内动脉的阻力指数、切率之间呈线性弱相关(r=0.30～0.36,P＜0.05). 结论老年高血压患者脉压增大,左室质量指数增加,颈动脉血管扩张,中内膜增厚,阻力指数增大、切率降低,粥样斑块形成,血管壁硬度增加使顺应性下降.

Ultrasound evaluation of the carotid artery hemodynamics in hypertensive elders

BACKGROUND: Non-invasive vascular ultrasound is used to assess in tima-media thickness (IMT) and atheromatous plaque, of which the result is better correlated to that of pathological examination. OBJECTIVE: Non-invasive vascular ultrasound was used to assess the hemodynamical changes of external and internal carotid in hypertensive elders, so as to investigate the relationship between pulse pressures, left ventricular mass index (LVMI), vascular resistance index (VRI) and shearing ratio. DESIGN: Randomized, controlled, correlative analyzedstudy. SETTING: Ultrasound Department of Affiliated Hospital of Jiangshu University. PARTICIPANTS: Totally 54 hypertensive elders, including 33 males and 21 females, were recruited from the Ultrasound Department of Affiliated Hospital of Jiangshu University, from September 30th 2000 to March 30th 2002. Meanwhile 26 normotensive elders (systolic pressure ＜ 130 mm Hg and/or diastolic pressure ＜ 85 mm Hg), including 16 males and 10 females, were selected as controls, METHODS: Color duplex blood flow imaging technique was used to assess the left ventricular end-diastolic diameter (LVEDD) and the interventricular septum thickness (IVST), so as to calculate the LVMI. The insiddiameter of bilateral common carotid artery (CCA) and internal carotid,IMT, the systolic peak flow velocity and resistance index were measured in order to calculate the vascular shearing ratio and atheromatous plaque index,moreover arterial pressure, LVMI, as well as resistance index and shearing ratio were subjected to linear correlative analysis,of which the results were compared with that of control group. MAIN OUTCOME MEASURES: ① Pulse pressure, LVMI and atheromatous plaque index of CCA. ② The inside diameter of bilateral CCA and internal carotid, IMT and the systolic peak flow velocity and resistance index were measured in order to calculate the atheromatous plaque index and maximum vascular shearing ratio. RESULTS: According to the experimental objective,data of all 80 cases were analyzed without loss. ① The pulse pressure and LVMI, the incidence of atheromatous plaque and plaque index of CCA in hypertensive elder group were obviously higher than that of control group (64.36±7.44) mm Hg,(45.78±8.72) mm Hg; (131.47±18.73) g/m2, (83.28±12.34) g/m2; 5.62 ±1.78,3.44±1.10; 66.7％, 23.1％, (x2=13.37, t=5.730-13.234, P ＜ 0.01)]. ② The inside diameter of bilateral CCA and internal carotid, IMT and resistance index in hypertensive elders were significantly higher than that of control group CCA: (8.96±1.20) mm, (8.08±0.96) mm; (1.28±0.88) mm, (0.91±0.17) mm;0.75±0.05, 0.69±0.06; ICA: (6.82±1.12) mm, (5.72±0.92) mm; (1.06±0.17) mm,(0.76±0.15) mm; 0.70±0.07, 0.64±0.06, t=2.872-10.850, P ＜ 0.01], but the systolic peak flow velocity and shearing ratio were markedly lower than that of control group CCA: (47.44±12.85) cm/s, (60.20±14.32) cm/s;(225.78 ±95.76)/s, (300.26 ±110.42)/s. ICA: (41.22 ±10.18) cm/s,(48.64±11.58) cm/s; (268.54±112.56)/s, (324.52±121.42)/s, t=2.872-10.850, P ＜ 0.01]. ③ The pulse pressure, LVMI, the resistance index of CCA and ICA and shearing ratio were linearly correlated (r=0.30-0.36, P ＜ 0.05). CONCLUSION: Pulse pressure and LVMI were found increased in hypertensive elders, together with carotid vessels dilated, IMT and resistance index increased, as well as shearing ratio decreased, atheromatous plaque formed, vascular stiffness increased, which resulted in consequently decrease of vascular compliance.