The end-systolic pressure-volume relation and its application to the study of the contractility of the cardiac muscle

The theory of large elastic deformation is used to develop a model for the contraction of the myocardium in which the active force of the myocardium (active fibre stress) is represented by its components in three perpendicular directions as force per unit volume of the myocardium. New results have been derived in relation to the study of the contractility of the myocardium, the study of the end-systolic pressure-volume relation (espvr) and the areas enclosed under it, as well as the calculation of the active and passive stress in the myocardium. Possibility of non-invasive implementation of some of those results by using for instance M-mode echocardiography is also indicated.