Study limitations
This study utilized a prospectively acquired single dataset of 3DE
images in normal children, and therefore the findings need to be
validated among cases with abnormal volumes, as agreement may diverge
outside of the normal ranges. This was not a study on feasibility, and
therefore we did not attempt to capture the number of children in which
insufficient image quality could be obtained. We did not compare the two
software directly to CMR which is considered the current reference
standard, however, given TomTec 4D LV-analysis has been directly
compared in previous large studies in measuring both LA and LV volumes
and ejection/emptying fraction, we felt it was reasonable to use it as a
reference6,7. We also acknowledge that 3DE has
limitations related to the temporal resolution and spatial lateral
resolution in the depth.