Quantitation of Right and Left Ventricular Volumes and Ejection Fraction in Case of Right Heart Overload

by Denisa Muraru, MD, PhD; Patrizia Aruta, MD
Department of cardiac, thoracic and vascular sciences, University of Padua, School of Medicine, Padua, Italy

Clinical Case

  • Male, 20 year-old
  • Corrected Tetralogy of Fallot (ToF) at 6 months of age
  • Asymptomatic
  • Referred for routine echocardiographic follow up

Two-dimensional 4-chamber view, showing a dilated, apex-forming right ventricle (RV) and a relatively smaller left ventricle (LV)

By two-dimensional echocardiography, it was practically impossible to obtain a correct 2-chamber view of the LV in order to calculate biplane LV volumes and ejection fraction by Simpson’s method. The LV appeared foreshortened in the 2-chamber view due to the markedly enlarged RV visible at the apex and anteriorly.

Three-dimensional echocardiographic analysis of the RV (4D RV Function 2.0®, TomTec Imaging System, Germany), showing a severely dilated RV with preserved ejection fraction.

Three-dimensional echocardiographic analysis of the LV (4D AutoLVQ, GE Vingmed, Horten, Norway) enabled first to achieve an optimal alignment of the LV data set and correct for LV foreshortening in 2-chamber view (the alignment of the vertical plane is set to cross the LV apex in all apical views in diastole). The volumetric reconstruction of LV cavity and semi-automated 3D analysis throughout the cardiac cycle provided the LV volumes and ejection fraction.

In multi-planar display above, you may also appreciate the large translation of the LV apex with respect to a fixed longitudinal axis (dashed line), being pulled towards the dilated, apex-forming RV during systole. This motion is even more evident in apical long-axis view (bottom left) and is responsible for the inability to obtain adequate conventional 2D biplane views of the LV required for Simpson’s method, particularly in 2-chamber view (see top right) and in end-systolic frame.

Diastole

Systole

To obviate this problem and still be able to obtain meaningful quantitative data on LV size and function by echocardiography, only a volumetric type of acquisition and analysis can be performed by transthoracic 3D echocardiography.

Multi-beat RV 3D dataset shown in 12 slice display

Multi-beat LV 3D dataset shown in 12 slice display

The same multi-beat RV 3D dataset above is shown in 3D rendered display, which allows to appreciate the anatomy and spatial relationship among all 4 cardiac valves

Important, a single good-quality 3D data set can serve for multiple purposes:

  • qualitative assessment (visual estimation of global ventricular size, shape and function; comprehensive wall motion analysis);
  • quantitative assessment (volumes, ejection fraction +/- mass, strain, torsion, dyssynchrony etc);
  • dynamic anatomy and function of valves
  • spatial relationship among cardiac structures

Key Messages

2D echocardiography:

  • Enabled the visual identification of an altered geometry of the heart chambers, in the context of RV volume overload, and to obtain qualitative and semi-quantitative information on ventricular size and function
  • Did not allow a reliable quantitation of LV and RV volumes and ejection fraction

3D echocardiography:

  • Enabled to perform semi-automated measurements of LV and RV volumes and ejection fraction without any geometrical assumption or reliance on tomographic planes
  • Allowed us to better understand the reasons for the limitations of conventional 2D echocardiography in assessing LV by Simpson’s biplane method in cases with altered geometry due to right heart overload
  • Provides a wealth of information regarding all cardiac structures encompassed within the 3D data set (including regional wall motion and valve dynamic anatomy and function)

References

  • Lang RM, Badano LP, Mor-Avi V et al. Recommendations for Cardiac Chamber Quantification by Echocardiography in Adults: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2015;28(1):1-39.
  • Simpson JM, Miller O. Three-dimensional echocardiography in congenital heart disease. Arch Cardiovasc Dis 2011; 104: 45-56
  • Badano LP. The clinical benefits of adding a third dimension to assess the left ventricle with echocardiography. Scientifica (Cairo). 2014;2014:897431.