中文摘要：

目的采用分层二维斑点追踪显像技术评价血液透析对左心室功能的影响。方法连续入组长期血液透析（≥6个月）患者28例，分别于透析前后采集患者二维短轴及长轴图像，同时采集年龄、性别相匹配的28例健康志愿者作为对照组，采用分层二维斑点追踪显像技术进行脱机分析，获得左室分层应变参数，同时获得左室18节段纵向应变达峰时间标准差（TT—SDI），采用Simpson法测量透析前后的左室舒张末容积（LVEDV）、左室收缩末容积（LVESV），计算左室射血分数（LVEF）。结果对照组、透析后组、透析前组的LVEDV依次增加，差异均有统计学意义（均P〈0．05）；LVEF在对照组和透析前组中差异无统计学意义（P=0．391），透析后有所降低（P=0．06）。对照组、透析前组和透析后组左室内膜环向应变（CS—endo）及纵向应变（LS-endo）、中层心肌环向应变（CS—mid）及纵向应变（LS-mid）、外膜环向应变（CS-epi）及纵向应变（LS-epi）依次减小（均P〈0.01），而同步性参数TT-SDI依次增大（均P〈0．01），且超滤量与透析前后左室纵向应变的差值显著相关（LS-endo差值：r=-0．428，P=0．023；LS-mid差值：r=-0．423，P=0．025；LS—epi差值：r=-0．422，P=0．025）。结论血液透析可造成患者的左室应变显著下降，收缩功能减退，且收缩同步性变差；透析患者控制入水量，减少超滤量可达到保护心肌细胞的作用。

英文摘要：

Objective To evaluate the impact of maintenance hemodialysis（MHD） on left ventricular （LV） strains via layer-specific speckle-tracking imaging （LSTI）. Methods Twenty-eight MHD patients and 28 matched controls were enrolled in the study. Conventional echocardiography and LSTI were performed on patients before and shortly after one hemodialysis session, as well as on controls. Results LV end-diastolic volume （LVEDV） were markedly reduced after one session of HD [（52.3 ± 22.4）ml/m^2 vs （55.0± 15.3）ml/m^2 , P = 0.033], but still larger than the control group （47.4 ± 6.4） ml/m^2 . LV ejection fraction （LVEF） decreased in MHD patients after HD [（62.5 ±8.1）% vs （64.6 ±7.3）%, P =0.06], which was similar to those in the control group （66.0 ± 4.2）% and in MHD patient before HD （P = 0. 391 ）. The three layer circumferential and longitudinal strains decreased in the order of the control group, patients before liD and after liD [CS-endo：（-26.3±3.6）% vs （-22.2±4.7）% vs （- 19.2±5.4）%; CS-mid：（- 19.0±2.7）% vs （-15.3±3.5）% vs （-13.0±3.8）%;CS-epi：（-11.1 ±2.3）% vs （-8.0±2.6）% vs （-6.5±2.3）%;LS-endo：（-23.7±3.0）% vs （-18.6 ± 3.6）% vs （-16.4 ± 4.5）%; LS- mid：（ -20.9±2.7）% vs （-16.3±3.1）% vs （-14.0±4.1）%;LS-epi：（-18.4±2.4）% vs （-14.1 ±2.8）% vs （ - 12.0 ± 3.6）% ; all P 〈0.01], while the synchrony index, standard deviation of times to peak longitudinal strain, increased in these three groups [-（3.6± 1.0） % vs （6.3 ± 1.5） % vs （7.5± 2.2） %, all P〈0.01]. Linear correlation analysis showed ultrafiltration volume was negatively related with the difference of longitudinal strains before and after HD （difference of LS-endo： r = - 0. 428, P = 0.023 ; difference of LS-mid ： r = - 0. 423, P = 0. 025 ; difference of LS-epi： r = - 0. 422, P = 0. 025）. Conclusions One session of HD may have injurious effects on LV strains and systolic synchrony. The reduction of ultra