THE FOLLOWING is an exhibit of the Dodrill-GMR Mechanical Heart. This was displayed at the 1953 session of the American Medical Association in New York and won the Hektoen Bronze Medal for original investigation. Since that time, it has been requested by, and given to, the Smithsonian Institution of Washington, D. C., for permanent preservation.
A close-up photograph of one side of the mechanical heart is seen in Figure 1. The opposite side is similarly constructed except that the pressures are different and the two sides of the mechanical heart are substitutes for the right and left ventricle.
In Figure 2 there is seen the individual valve units. Blood is withdrawn into the cylinder which is made of glass and contains a finger cot which is alternately inflated and deflated, thereby drawing blood into the chamber and expelling it. Six valves may be used on either side. The alternating pressure