Ng Arnold C, Tran Da T, Newman Mark, Allman Christine, Vidaic Jane, Lo Sidney T, Hopkins Andrew P, Leung Dominic Y
Department of Cardiology, Liverpool Hospital, University of New South Wales, Sydney, Australia.
J Am Soc Echocardiogr. 2008 Sep;21(9):1042-8. doi: 10.1016/j.echo.2008.05.002. Epub 2008 Jun 24.
The reference values and impact of physiologic variables on echocardiographic quantification of left ventricular (LV) synchrony in a large series of healthy persons are unknown. This study prospectively investigated the impact of age, gender, and other physiologic parameters on LV longitudinal and radial synchrony.
LV longitudinal systolic and diastolic synchrony using tissue Doppler imaging were measured as the standard deviation of times to 12 regional peak myocardial systolic Sm (SDTs) and early diastolic Em (SDTe) velocities in 122 healthy volunteers (age 19-68 years, 64 men). By using 2-dimensional speckle tracking, radial synchrony was measured as the standard deviation of times to 6 regional peak strain (SDTrepsilon) in the short-axis papillary muscle level. Longitudinal systolic synchrony was also measured as the standard deviation of times to 12 regional peak strain (SDTlepsilon).
The mean QRS duration and LV ejection fraction were 87 +/- 12 msec and 61% +/- 5.5%, respectively. The mean SDTs and SDTe were 37.1 +/- 17.4 msec and 17.3 +/- 6.7 msec, respectively. Gender and the mean Sm velocity from the 6 basal LV segments were independent predictors of SDTs, whereas the isovolumic relaxation time and mean Em velocity independently predicted SDTe. The mean SDTrepsilon was 19.2 +/- 14.6 msec. SDTrepsilon did not correlate with any clinical or echocardiographic parameters. The mean SDTlepsilon was 40.4 +/- 11.8 msec. Isovolumic relaxation time, pulmonary S/D ratio, and mean Sm independently predicted SDTlepsilon. There was no correlation between LV longitudinal and radial synchrony. Intraobserver and interobserver variability analyses showed the highest correlation for SDTs compared with SDTrepsilon and SDTlepsilon.
This study establishes normal reference ranges for LV systolic and diastolic synchrony measured with tissue Doppler velocity-based and 2-dimensional speckle tracking-based methods in a large group of healthy subjects of both genders across a wide age group. SDTs is gender specific and dependent on global LV systolic function, whereas SDTe is dependent on global LV diastolic function. Two-dimensional speckle-derived radial synchrony is independent of any clinical and echocardiographic variables but has higher intraobserver and interobserver variability compared with SDTs. LV longitudinal synchrony does not correlate with radial synchrony.
在大量健康人群中，生理变量对左心室（LV）同步性超声心动图定量的参考值及影响尚不清楚。本研究前瞻性地调查了年龄、性别和其他生理参数对LV纵向和径向同步性的影响。
采用组织多普勒成像测量LV纵向收缩期和舒张期同步性，即122名健康志愿者（年龄19 - 68岁，64名男性）12个区域心肌收缩期峰值Sm速度（SDTs）和舒张早期Em速度（SDTe）到达时间的标准差。通过二维斑点追踪，在短轴乳头肌水平测量径向同步性，即6个区域峰值应变到达时间的标准差（SDTrepsilon）。纵向收缩期同步性也通过12个区域峰值应变到达时间的标准差（SDTlepsilon）来测量。
平均QRS时限和LV射血分数分别为87±12毫秒和61%±5.5%。平均SDTs和SDTe分别为37.1±17.4毫秒和17.3±6.7毫秒。性别和LV 6个基底节段的平均Sm速度是SDTs的独立预测因素，而异长舒张时间和平均Em速度独立预测SDTe。平均SDTrepsilon为19.2±14.6毫秒。SDTrepsilon与任何临床或超声心动图参数均无相关性。平均SDTlepsilon为40.4±11.8毫秒。异长舒张时间、肺S/D比值和平均Sm独立预测SDTlepsilon。LV纵向和径向同步性之间无相关性。观察者内和观察者间变异性分析显示，与SDTrepsilon和SDTlepsilon相比，SDTs的相关性最高。
本研究建立了在一大组不同年龄的男女健康受试者中，基于组织多普勒速度法和二维斑点追踪法测量LV收缩期和舒张期同步性的正常参考范围。SDTs具有性别特异性且依赖于整体LV收缩功能，而SDTe依赖于整体LV舒张功能。二维斑点衍生的径向同步性独立于任何临床和超声心动图变量，但与SDTs相比，观察者内和观察者间变异性更高。LV纵向同步性与径向同步性无相关性。
