尿毒症患者心室-动脉耦联的超声定量评估

摘要

目的 探讨超声射频信号血管内中膜分析(QIMT)、动脉硬度分析(QAS)、应变及应变率成像分析(XStrain)技术在评价尿毒症患者心室-动脉耦联(VAC)中的应用价值.方法 尿毒症患者65例,正常受试者30例,均接受心脏及颈动脉超声检查,获得左室射血分数(LVEF)、Tei指数、E/e、僵硬度(β)、顺应性系数(CC)、脉搏波传导速度(PWV)、内中膜厚度(IMT)、应变等指标.以左心室收缩期最大径向应变与颈动脉舒张期最大径向应变之和作为评价VAC的应变指标(VACs),与传统的容积指标(VACv)进行相关分析.将各项指标进行组间比较,以反映尿毒症患者心血管功能及VAC的改变.采用多元线性回归以及ROC曲线分析预测尿毒症患者心功能不全的独立预测因子,评估各因子的贡献,并探讨其理想界值.应用组内相关系数检验XStrain的重复可靠性.结果 ①尿毒症组脉压差、E/e、Tei指数、β、PWV以及IMT均显著高于对照组(P＜0.05).②尿毒症组VAC功能下降,其VACv及VACs均显著低于对照组(P ＜0.05).③VACs作为一项评价VAC的新指标与传统的VACv具有高度的相关性(r=0.908,P=0.000),其测量方法XStrain具有较高的重复可靠性.④VACs、β、VACv和PWV是预测尿毒症患者心功能状态的独立预测因子,其中VACs对心功能状态的影响最大(标准化回归系数为-0.582).以VACs＜23.60作为判断尿毒症患者心功能不全的诊断标准,其灵敏性和特异性均较高(96.4％和81.1％).结论 QIMT、QAS以及XStrain等技术可用来全面综合评估尿毒症患者心血管结构、功能以及VAC的异常情况,为早期发现尿毒症心血管并发症、改善患者预后提供有效的方法.%Objective To investigate the clinical value of quality intima-media thicknes (QIMT),quality arterial stiffness(QAS) and XStrain in assessing the ventricular-arterial coupling (VAC) in patients with uremia.Methods Sixty-five patients with uremia and 30 normal subjects were enrolled in this study as the uremic group and control group respectively.Ultrasound examination for the cardiac and carotid artery was performed and some parameters were obtained,such as left ventricular ejection fraction(LVEF),E/e,Tei index,stiffness (β),compliance coefficinet (CC),pulse wave velocity (PWV),intima-media thicknes (IMT),strain,and so on.The sum of left ventricular systolic radial strain and carotid arterial diastolic radial strain was used as a new parameter (VACs) for assessing VAC.The correlation between VACs and VACv,a traditional method to evaluate VAC,was analyzed.The parameters obtained by ultrasonic techniques were compared between two groups.The intra-and inter-observer reliability of XStrain was assessed by intraclass correlation coefficient.The multiple linear regression and ROC curve were used to analyze the independent factor of cardiovascular dysfunction.Results ①The pulse pressure,E/e,Tei index,as well as β,PWV and IMT were larger in uremic group than control group significantly (P ＜0.05).②The function of VAC was decreased in uremic group,and the VACv and VACs were lower than control group significantly (P ＜0.05).③There was strong positive relation between VACs and VACv (r =0.908,P =0.000).The reproducibility of XStrain technique was well.④VACs,β,VACv and PWV could be considered as independent factor of cardiovascular dysfunction and performance of VACs was the largest (standardized coefficient was-0.582).A cutoff value of VACs for assessing cardiovascular dysfunction was less than 23.60,which had both higher sensitivity and specificity (96.4％,81.1％).Conclusions The QIMT,QAS and XStrain can be used to assess cardiovascular structure,function and VAC accurately and globally,which can be consider as an effective method for detecting cardiovascular complication and improving prognosis of uremic patients.