Factors Relating to the Application of Radioisotopes to Circulatory Support Systems

Radioisotope power supplies for heart assist devices and total replacements are being developed. In a radioisotopically powered artificial heart, heat from the decay of radioisotopes would be converted to fluid power to operate a blood pump. Radioisotope power sources offer the advantages of being completely implantable and having a relatively long life. Initial efforts have been directed toward developing conceptual designs of radioisotope heat engines, evaluating candidate radioisotopes fuel forms, and studying the radiation doses to be expected from the various fuel forms. Conceptual design studies indicate that a power supply capable of meeting the specifications of a circulatory support system can be developed. The most promising fuel is plutonium-238. Radiation does not appear to be a problem.