Background

As the potential for cancer therapy–related cardiac dysfunction is increasingly recognized, there is a need for the standardization of echocardiographic measurements and cut points to guide treatment. The aim of this study was to determine the reproducibility of cardiac safety assessments across two academic echocardiography core laboratories (ECLs) at the University of Pennsylvania and the Duke Clinical Research Institute.

Methods

To harmonize the application of guideline-recommended measurement conventions, the ECLs conducted multiple training sessions to align measurement practices for traditional and emerging assessments of left ventricular (LV) function. Subsequently, 25 echocardiograms taken from patients with breast cancer treated with doxorubicin with or without trastuzumab were independently analyzed by each laboratory. Agreement was determined by the proportion (coverage probability [CP]) of all pairwise comparisons between readers that were within a prespecified minimum acceptable difference. Persistent differences in measurement techniques between laboratories triggered retraining and reassessment of reproducibility.

Results

There was robust reproducibility within each ECL but differences between ECLs on calculated LV ejection fraction and mitral inflow velocities (all CPs < 0.80); four-chamber global longitudinal strain bordered acceptable reproducibility (CP = 0.805). Calculated LV ejection fraction and four-chamber global longitudinal strain were sensitive to small but systematic interlaboratory differences in endocardial border definition that influenced measured LV volumes and the speckle-tracking region of interest, respectively. On repeat analyses, reproducibility for mitral velocities (CP = 0.940–0.990) was improved after incorporating multiple-beat measurements and homogeneous image selection. Reproducibility for four-chamber global longitudinal strain was unchanged after efforts to develop consensus between ECLs on endocardial border determinations were limited primarily by a lack of established reference standards.

Conclusions

High-quality quantitative echocardiographic research is feasible but requires a commitment to reproducibility, adherence to guideline recommendations, and the time, care, and attention to detail to establish agreement on measurement conventions. These findings have important implications for research design and clinical care.

中文翻译：

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超声心动图核心实验室在心脏肿瘤学中安全性评估的可重复性

背景

随着人们越来越认识到与癌症治疗有关的心脏功能障碍的潜力，需要对超声心动图测量和切点进行标准化以指导治疗。这项研究的目的是确定宾夕法尼亚大学和杜克临床研究所的两个学术超声心动图核心实验室（ECL）之间的心脏安全性评估的可重复性。

方法

为了协调指南推荐的测量惯例的应用，ECL进行了多次培训，以使测量方法与传统的和新兴的左心室（LV）功能评估相一致。随后，每个实验室分别分析了25例接受阿霉素治疗，有或没有曲妥珠单抗治疗的乳腺癌患者的超声心动图。一致性是由在预定的最小可接受差异内的读者之间所有成对比较的比例（覆盖率[CP]）确定的。实验室之间在测量技术上的持久差异引发了对可重复性的再培训和重新评估。

结果

每个ECL内均具有强大的重现性，但是ECL之间在计算出的LV射血分数和二尖瓣流入速度方面存在差异（所有CP均<0.80）；四腔整体纵向应变接近可接受的可重复性（CP = 0.805）。计算出的左室射血分数和四腔室整体纵向应变对心内膜边界清晰度的小而系统的实验室间差异敏感，这些差异分别影响所测量的左室体积和感兴趣的斑点追踪区域。在重复分析中，结合多次心搏测量和均匀图像选择后，二尖瓣速度的可重复性（CP = 0.940–0.990）得到了改善。

结论

高质量的定量超声心动图研究是可行的，但需要对可重复性做出承诺，遵守准则建议，并花费时间，精力和对细节的关注以建立测量约定。这些发现对研究设计和临床护理具有重要意义。