动静脉内瘘透析患者术侧肱动脉弹性与左心室功能Tei指数的变化及相关性研究

Research on changes of brachial artery elasticity and Tei index for left ventricular function and their correlation in patients with internal arteriovenous fistula undergoing hemodialysis

目的应用超声血管回声跟踪技术评价透析患者术侧肱动脉血管弹性的临床变化,同时结合患者心脏左心室组织多普心肌做功指数(Tei index,Tei指数)的变化,评价两种参数变化的相关性。方法收集行自体动静脉内瘘透析治疗患者55例,同时征集40例健康体检者作对照研究,应用超声血管回声跟踪技术检测患者术侧肱动脉弹性参数:僵硬指数(stiffness parameter,β)、弹性系数(elastic coefficient,Eρ)、顺应性(compliance,AC)、脉搏波传播速度(pulse wave velocity,PWVβ)、膨大指数(swelling index,AI)指标,同时应用组织多普勒超声测量左心室功能指标:等容收缩时间(isovolumic contraction time,ICT),等容舒张时间(isovolemic diastolic time,IRT),射血时间(ejection time,ET),计算Tei指数=(ICT+IRT)/ET、等容收缩指数(ICT/ET)和等容舒张指数(IRT/ET)。结果①透析组β、Eρ、PWVβ高于正常对照组,AC低于正常对照组(P<0.05),透析组AI与对照组比较差异无统计学意义(P>0.05);②透析组IRT/ET、Tei指数高于正常对照组(P<0.05),ICT/ET、ET组间比较差异均无统计学意义(P>0.05);③相关分析表明透析组IRT/ET与动脉弹性指数β、Eρ、PWVβ呈正相关(r=0.789、0.777、0.739,P<0.05),透析组IRT/ET与AC呈负相关(r=-0.442,P<0.05);Tei指数与β、Eρ、PWVβ呈正相关(r=0.667、0.617、0.979,P<0.05)。结论透析患者可通过超声检测出动脉弹性功能和左心室功能的改变,手术侧动脉弹性功能变化与左心室舒张功能变化呈正相关,左心室整体功能随着血管弹性的降低而减低,且以左心室的舒张功能减低较为显著,临床可以参考内瘘术后肱动脉弹性变化预测心血管并发症风险,以期及时有效进行干预心脏与血管病变的进程,降低透析患者心血管疾病的发病率及病死率。

Objective To evaluate the changes of brachial artery elasticity by echo-tracking technique and left ventricular Tei Index obtained by tissue Doppler imaging in patients undergoing hemodialysis,and to evaluate the correlation between two parameters.Methods We randomly selected 55 patients with autologous internal arteriovenous fistula(IAF)undergoing hemodialysis,and 40 healthy subjects were recruited as controls.The parameters of brachial artery elasticity,including stiffness parameter(β),elastic coefficient(Eρ),compliance(AC),pulse wave velocity(PWVβ),swelling index(AI),were measured by ET technique;in the meantime,left ventricular function was measured by tissue Doppler ultrasound,including isovolumic contraction time(ICT),isovolemic diastolic time(IRT),and ejection time(ET).Tei index(ICT+IRT)/ET,isometric contraction index ICT/ET and isometric relaxation index IRT/ET were calculated.Results①The levels ofβ,Eρ,and PWVβwere higher in the hemodialysis group than in the normal control group,while the AC was lower in the hemodialysis group than in the normal control group(P<0.05).No significant difference was found in AI between two groups(P>0.05).②The levels of IRT/ET and Tei index were higher in the dialysis group than in the normal control group(P<0.05),whereas no significant difference was found in the ICT/ET and ET between two groups(P>0.05).③Correlation analysis showed that IRT/ET in hemodialysis group was positively correlated with arterial elastic indexes includingβ,Eρ,and PWVβ(r=0.789,0.777,0.739,P<0.05),while IRT/ET in hemodialysis group was negatively correlated with AC(r=-0.442,P<0.05).Tei Index was positively correlated withβ,Eρand PWVβ(r=0.667,0.617,0.979,P<0.05).Conclusion Ultrasound could be used to detect the changes of arterial elastic function and left ventricular function in patients undergoing hemodialysis,and the changes of arterial elastic function are positively correlated with the changes of left ventricular diastolic function.The global function of the left ventricle decreased with the decrease of vascular elasticity,and the decrease of diastolic function of the left ventricle is more significant.The changes of brachial artery elasticity after fistulectomy can be used to predict the risk of cardiovascular complications,and the intervention process of heart and vascular disease should be performed early and effectively,thereby reducing morbidity and mortality of patients with cardiovascular disease undergoing hemodialysis.