Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu, Japan.
Nephrol Dial Transplant. 2011 May;26(5):1655-61. doi: 10.1093/ndt/gfq590. Epub 2010 Sep 23.
Abnormal myocardial loading can contribute to left ventricular (LV) mechanical dyssynchrony in patients with end-stage renal disease (ESRD). The aims of this study were to characterize and quantify LV function and mechanical dyssynchrony in patients with ESRD, and to elucidate the impact of haemodialytic (HD) therapy on these parameters by speckle-tracking strain imaging.
Twenty-three patients with ESRD (63 ± 11 years) before (pre-dialysis group) and after HD therapy (post-dialysis group) and 28 normal subjects (control group; 60 ± 10 years) were examined by echocardiography. Global and segmental LV peak systolic strain (PSS) were analysed, and LV mechanical dyssynchrony was assessed by calculating the standard deviation of the segmental time-to-PSS over longitudinal, circumferential or radial regions, respectively.
Global PSS and LV ejection fraction in the pre-dialysis group were similar to those in the control group, and were not altered by HD therapy. LV mechanical dyssynchronies in the longitudinal and radial directions, but not in the circumferential direction, were significantly greater in the pre-dialysis group than those in the control group [longitudinal direction: 63 ± 15 (P < 0.05 vs. the control group) vs. 49 ± 15 ms, circumferential direction: 44 ± 24 vs. 41 ± 23 ms, and radial direction: 47 ± 29 (P < 0.05 vs. the control group) vs. 16 ± 18 ms]. HD therapy dramatically improved only the radial LV dyssynchrony in the post-dialysis group (23 ± 24 ms, P < 0.05 vs. the pre-dialysis group).
The presence of ESRD was associated with longitudinal and radial LV dyssynchronies. In addition, HD therapy dramatically improved radial LV dyssynchrony, which strongly indicates that only radial LV dyssynchrony is preload dependent among the three LV systolic directions.
异常的心肌负荷可导致终末期肾病(ESRD)患者左心室(LV)机械不同步。本研究的目的是通过斑点追踪应变成像来描述和量化 ESRD 患者的 LV 功能和机械不同步,并阐明血液透析(HD)治疗对这些参数的影响。
对 23 例 ESRD 患者(透析前组,63±11 岁)和 23 例 ESRD 患者在 HD 治疗后(透析后组,63±11 岁)及 28 例正常对照者(对照组,60±10 岁)进行超声心动图检查。分析整体和节段性 LV 收缩期峰值应变(PSS),并通过计算节段性 PSS 时间的标准差,分别评估 LV 机械不同步在长轴、环向或径向方向上的情况。
透析前组的整体 PSS 和 LV 射血分数与对照组相似,且 HD 治疗并未改变。与对照组相比,透析前组的纵向和径向 LV 机械不同步显著更大(纵向:63±15[P<0.05 与对照组]比 49±15ms,环向:44±24 比 41±23ms,径向:47±29[P<0.05 与对照组]比 16±18ms),但环向方向的 LV 机械不同步无显著差异。在透析后组,HD 治疗仅显著改善了径向 LV 不同步(23±24ms,P<0.05 与透析前组)。
ESRD 的存在与 LV 纵向和径向不同步有关。此外,HD 治疗显著改善了径向 LV 不同步,这强烈表明在三个 LV 收缩方向中,只有径向 LV 不同步是前负荷依赖性的。