The electric analogue of the systemic circulation consists of systemic arterial section implemented with a 4-WM in which Ras represents the systemic variable peripheral resistance. The systemic veins section is reproduced by a 2-WM  in wich Rvs represents the systemic venous variable resistance. In the network Pt is the mean intrathoracic pressure, Rcs is the systemic characteristic resistance, Las is the systemic arterial inertance. Cas (Cvs) is the systemic arterial (venous) compliance.