Twin calves, total artificial heart, cardiac transplantation

Numerous laboratories throughout the world are successful in sustaining life in calves, sheep, and goats implanted with total artificial hearts for 4-8 months. Very good reliability has been demonstrated with some of these devices, and all of the more successful devices are pneumatically driven. These pneumatic controllers are, for the most part, large and nonportable, and thus are criticized when considered for permanent tethering to a human recipient. The artificial hearts, however, have been developed to a stage where they could sustain the circulation for indeterminate periods of time, for 2-3 years. The pneumatic total artificial heart was used for a few weeks in calves, and then followed with cardiac transplantation. This format has been suggested for human application.