The artificial heart: device and concept evolution.

In the artificial heart area, device evolution and evolution of application criteria have been synergetic in promoting advancement in the entire sector. In fact, limitations of conventional therapies prompted the short-term use of devices for supporting patients until heart transplantation or until recovery of natural heart function. This in turn stimulated device diversification. A first class of new intraventricular blood pumps, allowing simplified application procedures, but with limitation in blood flow, have been developed for short term mechanical support. Another class of devices, with more implantable components, have been developed for longer duration applications, and higher quality of patient life during the implant period. These temporary but progressively longer duration clinical applications in patients waiting for heart transplantation, demonstrated the clinical feasibility of permanent support or substitution of a failing heart; an application intended as an alternative to heart transplantation that is greatly limited by donor's organ availability. Research efforts are now focused on establishing readiness for permanent clinical use of totally implantable heart replacing systems, or of implantable devices for assisting left ventricular function.