Why is apical foreshortening a problem for 3D LV volume estimation, and how can you minimize it?

• A. It underestimates cavity size and volumes; minimize by optimizing apical views to avoid cutting off the apex and ensuring full visualization in 3D.
• B. It overestimates volumes; minimize by using shallow breathing.
• C. It has no effect on volume estimates.
• D. Foreshortening increases measured LV mass.

Answer: (A)

Apical foreshortening shortens the LV long axis in the image, so the apex isn’t fully captured. In 3D LV volume estimation, the endocardial borders are traced across the whole chamber from base to apex, and missing the apex makes the cavity look smaller. That leads to underestimation of both end-diastolic and end-systolic volumes, and thus the stroke volume and ejection fraction can be biased downward.

To minimize it, optimize the apical window so the apex is fully visualized. Adjust the transducer angle and rotation to obtain true long-axis views, and use a full-volume 3D acquisition with breath-hold when possible to reduce motion. Confirm apex visualization in multiple perspectives (for example, apical 2- and 4-chamber views or an orthogonal view) and ensure the dataset includes the entire long axis from base to apex without cropping the apex during reconstruction.

Shallow breathing isn’t a reliable fix, and foreshortening more commonly leads to underestimation of volumes rather than overestimation, so it wouldn’t cause the LV mass to increase.