The volume of the left atrium can be calculated using an ellipsoid-biplane formula.
Parameters:
(1) anterior to posterior (AP) diameter in the parasternal long axis view in cm
(2) medial to lateral (ML) diameter in the parasternal short axis view in cm
(3) super to inferior (SI) diameter in the apical 4-chamber view in cm
volume of the left atrium in cubic cm =
= 4 * PI() / 3 * (AP diameter) / 2 * (ML diameter) / 2 * (SI diameter) / 2 =
= PI() / 6 * (AP diameter) * (ML diameter) * (SI diameter)
