Division of Cardiology, The Labatt Family Heart Centre, Department of Paediatrics, Hospital for Sick Children and University of Toronto, Toronto, Ontario, Canada.
J Am Soc Echocardiogr. 2011 Nov;24(11):1191-8. doi: 10.1016/j.echo.2011.08.006. Epub 2011 Sep 15.
Assessment of right ventricular (RV) volumes and function is important in patients after tetralogy of Fallot (TOF) repair. Currently, cardiac magnetic resonance imaging (MRI) is considered the clinical reference method for RV volume and function measurements. Three-dimensional (3D) knowledge-based reconstruction derived from two-dimensional echocardiographic imaging with magnetic tracking is a novel approach to RV volumetrics. The aim of this study was to assess the feasibility and reliability of this novel echocardiographic technique in patients after TOF repair. The accuracy of the method was assessed by comparison with measurements obtained by cardiac MRI.
Thirty patients (mean age, 13.7 ± 2.8 years) after TOF repair, referred for cardiac MRI, were included. Immediately after MRI, echocardiographic image acquisition was performed using a standard ultrasound scanner linked to a Ventripoint Medical Systems unit. Echocardiographic and MRI measurements were performed offline. Parameters analyzed were end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction. Intraobserver, interobserver, and intertechnique variability was assessed using Pearson's correlation analysis, coefficients of variation, and Bland-Altman analysis.
Echocardiographic two-dimensionally based 3D reconstruction was highly feasible, with low intraobserver and interobserver variability for EDV and slightly higher variability for ESV and ejection fraction. The 3D reconstruction values for EDV, ESV, and ejection fraction were correlated highly with MRI values, with low coefficients of variation. The agreement between both methods was high. Three-dimensional reconstruction slightly underestimated RV volumes, by 2.5% for EDV and 4.6% for ESV compared with MRI volumes.
In patients after TOF repair, echocardiographic 3D reconstruction is highly feasible, with good reproducibility for measurements of RV EDV. There is good agreement with MRI measurements, with a small underestimation of RV volumes. The use of this method in clinical practice warrants further investigation.
评估法洛四联症（TOF）修复后的右心室（RV）容积和功能非常重要。目前，心脏磁共振成像（MRI）被认为是 RV 容积和功能测量的临床参考方法。基于知识的三维（3D）重建源自带磁跟踪的二维超声心动图成像，是一种 RV 容积测量的新方法。本研究旨在评估该新型超声心动图技术在 TOF 修复后的患者中的可行性和可靠性。该方法的准确性通过与心脏 MRI 测量值进行比较来评估。
本研究纳入了 30 例 TOF 修复后接受心脏 MRI 检查的患者（平均年龄 13.7±2.8 岁）。在 MRI 检查后，立即使用与 Ventripoint Medical Systems 单元相连的标准超声扫描仪进行超声心动图图像采集。在离线状态下进行超声心动图和 MRI 测量。分析的参数包括舒张末期容积（EDV）、收缩末期容积（ESV）和射血分数。采用 Pearson 相关分析、变异系数和 Bland-Altman 分析评估观察者内、观察者间和技术间的变异性。
超声心动图二维基础的 3D 重建具有高度可行性，EDV 的观察者内和观察者间变异性较低，ESV 和射血分数的变异性略高。3D 重建的 EDV、ESV 和射血分数值与 MRI 值高度相关，具有较低的变异系数。两种方法之间的一致性较高。与 MRI 容积相比，3D 重建略微低估了 RV 容积，EDV 减少 2.5%，ESV 减少 4.6%。
在 TOF 修复后的患者中，超声心动图 3D 重建具有高度可行性，RV EDV 测量具有良好的可重复性。与 MRI 测量值具有良好的一致性，RV 容积略有低估。该方法在临床实践中的应用值得进一步研究。
