Description:
<jats:title>Abstract</jats:title><jats:p>A clinically applicable method for determining right ventricular volume was developed using a new hemielliptical model. The model was derived from a detailed study of right ventricular geometry. Silicone rubber casts were made from 7 adult human right ventricles at autopsy. Cast volumes measured by water displacement ranged from 30 to 144 ml. Serial sections were made of each cast, and the product of the long and short axis of all sections was found to be directly related to the cross‐sectional area and independent of the region or the volume of the ventricle from which the slice originated. Further, using a hemielliptical model, the volume V of each ventricle could be calculated from the equation: V = (π/4) Σ dwh where, d is the depth, w is the width parallel to the septum, and h is the thickness of the cross section. Calculated volume agreed closely with displacement volume throughout (r equals; 0.99, slope equals; 1.05 ± 0.04, intercept equals; −3.6 ± 4., SEE equals; 4.27 ml). Using the same model, calculation of right ventricular surface area was found to agree closely with measured surface area (r equals; 0.99, slope equals; 0.94, intercept equals; −.6, SEE equals; 3.9).</jats:p><jats:p>This model can be used to calculate right ventricular volumes from biplane radiographs in man using the equation V equals; (π/4)(A<jats:sub>RAO</jats:sub>·A<jats:sub>LAO</jats:sub>)/Hsb<jats:sub>L</jats:sub> where A<jats:sub>RAO</jats:sub> equals; the area of the 30° right anterior oblique image, A, H<jats:sub>L</jats:sub> equals; the area and height respectively of the 60° left anterior oblique image. For all 7 casts, radiographic volume agreed closely with directly measured volume (slope equals; 0.97, intercept equals; −5.5, r equals; 0.99, SEE equals; 4.7). Evaluation of positional effects showed that radiographic volume was most accurate when the 30° RAO/60° LAO projections were used. This study provides a method of calculating right ventricular volume, based upon right ventricular geometry, that may be applied to evaluating the volume of the right ventricle in man.</jats:p>