Volume overload related shape change limits mass increase with wall thickening but only minimally reduces wall stress

A mathematical model was used to determine the influence of ellipsoid to spheroid left ventricular shape transformation, often seen during chronic volume overload, on ventricular mass, wall thickness, and regional wall stress. Simulated shape change predicted a mass decrease of 9% and a decrease in the maximum circumferential stress in comparison to stress normalizing hypertrophy. Both the simulation and clinical studies showed that apical wall stresses increased to 200-250% of normal with shape transformation. It is concluded that shape change offers a modest advantage of providing increased wall thickness for a given wall mass, and a reduction in maximum circumferential stress, but at the expense of greatly increased apical wall stresses, which may limit apical contractility