Stefani Laura, Toncelli Loira, Gianassi Marco, Manetti Paolo, Di Tante Valentina, Vono Maria Robertina Concetta, Moretti Andrea, Cappelli Brunello, Pedrizzetti Gianni, Galanti Giorgio
Non-Invasive Cardiac Laboratory of Sports Medicine Unit, University of Florence, Italy.
Cardiovasc Ultrasound. 2007 Feb 7;5:7. doi: 10.1186/1476-7120-5-7.
Myocardial contractility can be investigated using longitudinal peak strain. It can be calculated using the Doppler-derived TDI method and the non-Doppler method based on tissue tracking on B-mode images. Both are validated and show good reproducibility, but no comparative analysis of their results has yet been conducted. This study analyzes the results obtained from the basal segments of the ventricular chambers in a group of athletes.
30 regularly-trained athletes were submitted to an echocardiography at rest and after handgrip. Starting from the four-chamber view, overall myocardial function and regional velocities were evaluated. The images obtained were processed to determine strain in left and right ventricle basal segments. Strain was calculated using the TDI method and a validated "speckle tracking" or, more correctly, "feature tracking" algorithm. The statistical analysis included a Student's t-test (p < 0.05).
The range of strain values obtained is in agreement with the data reported in the literature. In the left ventricle (LV) the average strain values of the basal segments calculated with TDI on IVS and LW at rest and after stress were: -21.05 +/- 3.31; -20.41 +/- 2.99 and -20.05 +/- 2.61; -21.20 +/- 2.37, respectively. In the right ventricle (RV) the same method gave IVS and LW strain values at rest of -22.22 +/- 2.58 ; -24.42 +/- 5.84, and after HG of -22.02 +/- 5.20 ;-23.93 +/- 6.34. The values obtained using feature tracking were: LV at rest -20.48 +/- 2.65 for IVS, and -21.25 +/- 2.85 for LW; LV after HG: -19.48 +/- 3 for IVS and -21.69 +/- 3.85 for LW. In RV at rest: -21.46 +/- 3.25 for IVS and -24.13 +/- 5.86 for LW; RV after HG: -24.79 +/- 7.9 for IVS and -24.13 +/- 7.0 for LW. Tissue Doppler and "feature tracking" methods showed the respective consistency of the results in the basal segments of myocardial ventricle walls.
Provided that echographic imaging is good, strain can be computed in athletes by both Doppler-derived and tracking methods. It is technically feasible to use both -interchangeably, at least in basal segments.
可使用纵向峰值应变来研究心肌收缩力。它可以通过多普勒衍生的组织多普勒成像(TDI)方法和基于B模式图像上组织追踪的非多普勒方法来计算。这两种方法均经过验证且具有良好的可重复性,但尚未对其结果进行比较分析。本研究分析了一组运动员心室基底节段获得的结果。
30名经常训练的运动员在静息状态和握力试验后接受超声心动图检查。从四腔心视图开始,评估整体心肌功能和局部速度。对获得的图像进行处理,以确定左、右心室基底节段的应变。使用TDI方法和经过验证的“斑点追踪”(或更准确地说是“特征追踪”)算法计算应变。统计分析采用Student's t检验(p < 0.05)。
获得的应变值范围与文献报道的数据一致。在左心室(LV)中,静息和应激后用TDI计算的室间隔(IVS)和左心室壁(LW)基底节段的平均应变值分别为:-21.05±3.31;-20.41±2.99和-20.05±2.61;-21.20±2.37。在右心室(RV)中,相同方法得出静息时IVS和LW的应变值分别为-22.22±2.58;-24.42±5.84,握力试验后为-22.02±5.20;-23.93±6.34。使用特征追踪获得的值为:LV静息时IVS为-20.48±2.65,LW为-21.25±2.85;LV握力试验后:IVS为-19.48±3,LW为-21.69±3.85。RV静息时:IVS为-21.46±3.25,LW为-24.13±5.86;RV握力试验后:IVS为-24.79±7.9,LW为-24.13±7.0。组织多普勒和“特征追踪”方法显示了心肌心室壁基底节段结果的各自一致性。
只要超声心动图成像良好,运动员的应变可以通过多普勒衍生方法和追踪方法计算。至少在基底节段,两种方法可互换使用在技术上是可行的。