Abstract: A pumping device whose functioning resembles the action of the natural four chambered heart is constructed as a total cardiac replacement unit. An internal electrical drive motor adapted to be powered by radio frequency induction across intact skin drives an eccentric rotary element which in turn causes oscillation of pivoted vanes whose movements cyclically compress a pair of blood compatible sacs which simulate the left ventricle and right ventricle of the natural heart by pumping blood through the aorta and pulmonary artery, respectively. As in the natural heart, stroke volume of each ventricle is independent of the other and is a function of right atrial and left atrial pressure and volume. Additional embodiments of the invention feature modified driving means for the pumping vanes.