K. Y. Esther Leung PhD, Presenter: Nothing to Disclose

Heleen van der Zwaan MD, Abstract Co-Author: Nothing to Disclose

Osama Soliman MD, PhD, Abstract Co-Author: Nothing to Disclose

Gerard van Burken, Abstract Co-Author: Nothing to Disclose

Johan Bosch PhD, Abstract Co-Author: Nothing to Disclose

Jackie McGhie MSc, Abstract Co-Author: Nothing to Disclose

Jolien Roos - Hesselink, Abstract Co-Author: Nothing to Disclose

Folkert Meijboom MD, PhD, Abstract Co-Author: Nothing to Disclose

Marcel Geleijnse MD, PhD, Abstract Co-Author: Nothing to Disclose

Willem A. Helbing MD, PhD, Abstract Co-Author: Nothing to Disclose

Right ventricular (RV) volume estimation is important in patients with tetralogy of Fallot. In this study, we evaluate in detail why these volumes assessed by real-time three-dimensional echocardiography (RT3DE) differ from the cardiac magnetic resonance (CMR) reference.

Customized software was developed in-house to display images obtained by RT3DE and CMR side-by-side in optimal anatomical views. The endocardial contours, derived from semi-automated three-dimensional border detection for RT3DE and manual tracing of contours in multiple slices for CMR, were superimposed onto the images. Using the software, the RT3DE and CMR images were spatially aligned following a systematic and standardized protocol. The correspondence between the modalities was expressed as a three-dimensional translation and rotation, which was then used to align the RT3DE and CMR contours. This allowed the detailed assessment of regional differences in contour delineation of both modalities in one image. For quantitative assessment, a nine-segment model was used to estimate regional RV volume differences.

Images of 26 patients with tetralogy of Fallot were analyzed. RT3DE underestimated the global RV volume by 23 ± 26 ml in end-diastole and 10 ± 16 ml in end-systole. However, no statistically significant bias was found in ejection fraction (1.9 ± 6.3%). Volume differences were mainly caused by inferior visualization of the RV anterior wall by RT3DE, corroborated by regional quantitative analysis (46% difference in the anterior segments). The use of disk summation by CMR resulted in differences in the apical and pulmonary valve area. Trabeculae were more distinguishable from RV myocardium in CMR than in RT3DE; the wall appeared to be thicker in RT3DE.

The main sources of volume differences between RT3DE and CMR in this patient population are caused by suboptimal visualization of the RV anterior wall by RT3DE, the use of disk summation by CMR and the visualization and management of trabeculae. The understanding of this intermodality discordance will help to implement RT3DE into clinical practice.

Side-by-side comparison of three-dimensional echocardiography and cardiac magnetic resonance imaging leads to better understanding of differences in regional quantification of the right ventricle.

Leung, K, van der Zwaan, H, Soliman, O, van Burken, G, Bosch, J, McGhie, J, Roos - Hesselink, J, Meijboom, F, Geleijnse, M, Helbing, W, Right Ventricular Volumes in Patients with Tetralogy of Fallot: A Side-by-Side Comparison of 3D Echocardiography and Magnetic Resonance Imaging.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11007618.html Accessed May 4, 2025