An artificial heart is a prosthetic device that is implanted into the body to replace the original biological heart.
It is distinct from a cardiac pump, which is an external device used to provide the functions of both the heart and the lungs.
Thus, the cardiac pump need not be connected to both blood circuits.
Also, a cardiac pump is only suitable for use not longer than a few hours, while for the artificial heart the current record is 17 months.
This synthetic replacement for an organic mammalian heart (usually human), remains one of the long-sought goals of modern medicine.
Although the heart is conceptually a simple organ (basically a muscle that functions as a pump), it embodies complex subtleties that defy straightforward emulation using synthetic materials and power supplies.
The obvious benefit of a functional artificial heart would be to lower the need for heart transplants, because the demand for donor hearts greatly exceeds supply.
Note: The above text is excerpted from the Wikipedia article “Artificial heart“, which has been released under the GNU Free Documentation License.