In the electric analogue was plotted the interactions between the left and right ventricular free wall, the atria and the septa. In CARDIOSIM^© are implemented two different numerical models able to reproduce the behavior of the heart. The first one is described in Numerical Heart Model (1) section, the second one is shown in Numerical Heart Model (2) section. The CVS is represented using different circulatory compartments represented with a lumped parameter model (0-D model). In this configuration the CVS consists of: systemic and pulmonary arterial sections, systemic and pulmonary venous sections, coronary circulation and left and right heart. The ventricular, atrial and septal functions are implemented using a time-variable elastance model (see Numerical Heart Model (2) section).