AN ANALYTIC ELASTIC-VISCOELASTIC MODEL FOR SHAPE AND FORCES IN LEFT VENTRICLE

An analytic model of the human left ventricle is presented, which incorporates the three-dimensional shape of the left ventricle and the effects of ventricular wall thickness. The model resembles a thick-walled ellipsoid of revolution, a shape chosen because its volume most closely approximates the volume of postmortem left ventricular chambers when compared with volumes estimated by other regular three-dimensional figures of equivalent dimensions. The shape and size parameters of the model are determined from ventricular dimensions obtained from single plane cineangiocardiography. The model is equilibrated by a uniform internal normal stress, corresponding to the measured pressure in the ventricle cavity, and zero stress on the outer surface. Elastic and quasi-static viscoelastic solutions (for stresses and strains) that provide for shear in the ventricular wall are obtained for uniform isotropic wall material. © 1969.