血管环向应变在评价高血压患者颈动脉弹性中的价值

Value of the circumferential strain of the blood vessel in estimating the carotid arterial elasticity of the patients with hypertension

目的 探讨血管环向应变及应变率在评价颈动脉血管弹性中的价值.方法 选择高血压患者35名作为病例组,年龄匹配的健康志愿者36名作为对照组.对受试者双侧颈总动脉行内中膜检测,应用射频超声血管测量技术获得反映颈总动脉弹性的传统指标：包括脉搏波传播速度（PWV）、血管顺应性（AC） 应用X-strain技术获得反映血管应变的新指标,包括内膜纵向及环向应变（EN-LS,EN-CS）、内膜纵向及环向应变率（EN-LSR,EN-CSR）、外膜纵向及环向应变（EP-LS,EP-CS）、外膜纵向及环向应变率（EP-LSR,EP-CSR）等,进行两组间对比并分析高血压组弹性参数与血流动力学参数的相关性.结果 高血压组颈总动脉PWV较对照组显著增高（P＜0.05）,AC较对照组减低（P＜0.05）,差异具有统计学意义 高血压组环向应变指标EN-CS、EN-CSR、EP-CS、EP-CSR较对照组显著减低（P＜0.05）,纵向应变指标则无显著差异 高血压组的AC与PWV呈负相关,内、外膜环向应变及应变率均与PWV呈负相关,与AC呈正相关.结论 血管环向应变及应变率在反映血管弹性方面符合血管组织解剖结构特征和力学原理,能反映血管弹性的早期改变.

Objective To investigate the clinical value of circumferential strain and strain rate in estimating the carotid elasticity. Methods Thirty-five consecutive patients of hypertension were enrolled in this study as the patient group and 36 healthy volunteers whose ages were matched with the patient group were included as controls. The intima-media thickness（IMT） of common carotid arteries of both the patients and controls were measured using RF-Data technique of ultrasound vascular measurement and the following traditional parameters reflecting common carotid elasticity were obtained： pulse wave velocity （PWV）,arterial compliance （AC）. While the new parameters reflecting vascular strain including endovascular longitudinal strain（EN-LS）, endovascular circumferential strain（EN-CS）, endovascular longitudinal strain rate（EN-LSR） ,endovascular circumferential strain rate（EN-CSR）, adventitial longitudinal strain（EP-LS）,adventitial circumferential strain （ EP-CS ）, adventitial longitudinal strain rate （ EP-LSR ）, adventitial circumferential strain rate（EP-CSR） were collected using the technique of X-strain. All the corresponding parameters were compared between hypertensive group and controls. The correlations between elasticity and hemodynamic parameters were analyzed. Results In the hypertension patients,PWV was higher while AC,EN-CS,EN-CSR,EP-CS and EP-CSR were lower than that of the control group（ P 〈0.05）. No significant differences were detected in the longitudinal strain and strain rate. In the hypertension group,AC correlated positively with PWV, while EN-CS, EN-CSR, EP-CS and EP-CSR correlated negatively with PWV and positively with AC. Conclusions Circumferential strain and strain rate conform well to the mechanical principle and the characteristic anatomic and histological structure of the vessels and may be used to reflect the early changes of the vascular elasticity.