二维斑点追踪技术在保留左室射血分数尿毒症透析患者左室局部功能评价中的应用

Evaluation of the left ventricular regional function using two-dimensional speckle tracking echocardiography in uremia patients undergoing maintenance haemodialysis with preserved left ventricular ejection fraction

目的应用二维斑点追踪显像（2D—STI）技术评价保留左室射血分数（PLVEF）尿毒症透析患者左室局部功能。方法选择2013年12月～2015年10月在武汉大学人民医院及三峡大学人民医院就诊的左室射血分数正常（LVEF〉49％）的尿毒症血液透析患者31例（尿毒症组），同时选取年龄、性别匹配的29例健康志愿者为正常对照组。应用2D—STI测量左室径向、环向、纵向功能，用应变、应变率（含收缩期、舒张早期、舒张晚期）测值表示，并计算舒张早期与晚期应变率的比值。比较两组常规超声及左室径向、环向、纵向功能，做LVEF与左室收缩期峰值径向、环向、纵向应变的相关性分析及线性回归分析。结果①尿毒症组LVEF较正常对照组降低[（59±6）％比（65±4）％1，差异有高度统计学意义（P〈0．01）；②尿毒症组左室收缩期峰值纵向、径向应变值及舒张早期与晚期应变率比值均低于正常对照组（P〈0．05或P〈0．01），但两组的左室收缩期峰值环向应变值及舒张早期与晚期应变率的比值比较，差异均无统计学意义（P〉0．05）。③左室收缩期峰值环向应变与LVEF间有显著相关性（r=-0．432，P〈0．05），两者间呈线性关系（β=0．231，P〈0．05）。结论规律性血液透析的尿毒症患者出现左室结构及功能的显著改变，左室的收缩及舒张功能一并出现障碍，主要表现在左室径向及纵向的局部功能上，但左室的环向局部功能却能保持正常。左室收缩期峰值环向应变是LVEF的独立预测因子。应用2D—STE能早期检测出尿毒症患者左室局部心功能的异常及评估疾病的严重程度，并可提供有用的信息以指导对PLVEF尿毒症透析患者的危险程度进行分级。

Objective To evaluate the left ventricular regional function using two-dimensional speckle tracking imaging （2D-STI） in uremia patients with preserved left ventricular ejection fraction （PLVEF） undergoing haemodialysis. Methods Thirty-one uremia patients with PLVEF （LVEF〉49%） undergoing haemodialysis who were treated in Renmin Hos- pital of Wuhan University and Renmin Hospital of the Three Gorges University were enrolled in the study from December 2013 to October 2015 （uremia patient group）, and 29 normal subjects with age and sex matched were selected as healthy control group. The strain and strain rate （concluding systolic, early diastolic, late diastolic） values belonging to the radial, circumferential, and longtitudinal functions of the left ventricular have been measured by 2D-STI method, and the ratios between early and late diastolic strain rate were calculated. The conventional ultrasound results and the left ventricular regional functions in the radial, circumferential, and longtitudinal directions were compared between two groups. The correlation and linear regression tests between the systolic strain values in radial, circumferential, and longtitudinal directions and LVEF were analyzed respectively. Results （1）While the LVEF values in the uremia patient group were found to be lower than that in the healthy control group [（59±6）% vs （65±4）%], the difference was statisti- cally significant （P 〈 0.01）. （2）The values of systolic strain in the longtitudinal and radial directions were decreased in the uremia patient group, as well as the values of the strain rate ratio （early diastolic/late diastolic） were lower than those in the control group （P 〈 0.05 or P 〈 0.01）. However, there was no difference observed in terms of the values ofsystolic strain and strain rate ratio （early diastolic/late diastolic） in circumferential direction （P 〉 0.05）. （3）There was a significant correlation between the left ventricular systolic strain values in circumferential direction and LVEF （r = -0.432, P 〈 0.05）. There was also a linear regression relationship between these two parameters （β = 0.231, P 〈 0.05）. Conlusion Uremia patients undergoing regular haemodialysis appeared significant changes in left ventricular structures and functions. The systolic and diastolic functions of left ventricular are both declined, mainly displayed in the radial and longitudinal regional functions, while the circumferential regional function is preserved. The circumferential systolic strain is observed as an independent predictor related to the LVEF. 2D-STI can be used to detect the severity and the abnormal left ventricular regional functions of uraemic cardiomyopathy in the early stages of uremia patients and it might be used to provide useful information for the degree of the risk in uremia patients undergoing haemodialysis with PLVEF.