应变及应变率预测子痫前期颈总动脉弹性功能的价值

Value of strain and strain rate in predicting the elastic function of common carotid artery in preeclampsia

目的探讨应变及应变率预测子痫前期颈总动脉弹性功能的价值。方法选取在我院门诊产检的子痫前期孕妇30例(子痫前期组),以及年龄、孕周与之匹配的正常孕妇35例(健康对照组)。应用超声检测两组颈总动脉内中-膜厚度(IMT);血管弹性技术检测血管弹性指标,包括颈总动脉扩张系数(DC)、血管僵硬度(β)、脉搏波传播速度(PWV)、动脉增强压(AP);X-strain技术获取血管应变指标,包括血管内膜环向应变及应变率(EN-CS、EN-CSR),外膜环向应变及应变率(EP-CS、EP-CSR),径向应变及应变率(RAD-S、RAD-SR)。比较两组颈总动脉应变及应变率的差异;分析血管应变、应变率与血管IMT及弹性指标的相关性。绘制受试者工作特征曲线分析应变、应变率对子痫前期颈总动脉弹性功能降低的预测价值。结果子痫前期组EN-CS、EN-CSR及RAD-SR均较健康对照组降低,差异均有统计学意义(均P<0.01),其余应变指标两组比较差异均无统计学意义。子痫前期组EN-CS、EN-CSR、EP-CS、EP-CSR、RAD-S、RAD-SR均与PWV、β、IMT呈负相关(均P<0.05),均与DC、AP呈正相关(均P<0.05)。EN-CS、EN-CSR、RAD-SR及PWV预测子痫前期颈总动脉弹性功能降低的曲线下面积分别为0.74、0.750.84、0.68。结论子痫前期孕妇颈总动脉血管环向应变及径向应变率均降低,且均与血管弹性指标显著相关。颈总动脉应变及应变率对预测子痫前期血管弹性功能降低有一定价值。

Objective To evaluate the value of strain and strain rate in predicting the elastic function of common carotid artery in preeclampsia.Methods Thirty preeclampsia pregnant women(preeclampsia group)and 35 normal pregnant women(control group)with matched age and gestational age were selected for obstetric examination in our hospital.The common carotid artery intima-media thickness(IMT)was measured by ultrasonography in both groups.Vascular elasticity techniques were used to detect vascular elasticity indicators,including carotid artery dilation coefficient(DC),vascular stiffness(β),pulse wave propagation velocity(PWV),arterial enhancement pressure(AP).X-strain technique was used to obtain the vascular strain indicators,including the circumferential strain and strain rate(EN-CS,EN-CSR)of vascular intima,circumferential strain and strain rate(EP-CS,EP-CSR)of vascular adventitia,radial strain and strain rate(RAD-S,RAD-SR).The strain and strain rate of common carotid artery were compared between the two groups.The correlation between vascular strain,strain rate and IMT,vascular elasticity were analyzed.Receiver operating characteristic curve was drawn to analyze the predictive value of strain and strain rate on the decrease of common carotid artery elastic function in preeclampsia.Results EN-CS,EN-CSR and RAD-SR in the preeclampsia group were significantly lower than those in the control group,and the differences were statistically significant(all P<0.01),and there were no statistically significant difference in residual strain index between the two groups.EN-CS,EN-CSR,EP-CS,EP-CSR,RAD-S and RAD-SR were negatively correlated with PWV,βand IMT in the preeclampsia group(all P<0.05),positively correlated with DC and AP(both P<0.05).The area under curve of EN-CS,ENCSR,RAD-SR and PWV for predicting the reduction of common carotid artery elastic function in preeclampsia were 0.74,0.75,0.84 and 0.68,respectively.Conclusion The cyclic strain rate and radial strain rate of common carotid artery are decreased in preeclampsia pregnant women,and significantly correlated with vascular elasticity index.Common carotid artery strain and strain rate have certain value in predicting the decrease of vascular elastic function in preeclampsia.