The first entirely artificial heart should be ready for human trials 'within two and a half years', it was claimed yesterday. The prosthetic replacement would be fully implantable and could solve the worldwide shortage of donor hearts - estimated at 20,000 each year. Leading heart transplant specialist Alain Carpentier, head of the European research team that developed the prototype heart, said it was now ready to be manufactured and clinical trials will begin by 2011. Dr Carpentier said: 'We are moving from pure research to clinical applications. After 15 years of work, we are handing over to industry to produce an artificial heart usable by man.' The prototype was developed with the help of aerospace engineers. Shaped like a real heart, with the same blood flow rhythms, it uses similar technology to artificial heart valves already used around the world. The recurring problems of most artificial hearts - immune system rejection and blood clotting - are avoided by constructing it from chemically treated animal tissues. The device is designed for patients who have suffered a massive heart attack or late-stage heart failure, for whom drug therapy or heart transplant have failed or are not available. So far the heart has been tested with computer simulations, as well as on animals, with trials revealing 'no complications', Dr Carpentier said.          " DM He is now working with a biomedical firm to begin production at a site near Paris. Artificial assistance devices for hearts are already in use, while another kind of replacement acts as a temporary 'bridge' until a donor heart is found. But the Paris project is racing against teams in the U.S., Japan and South Korea to be the first to develop a totally artificial permanent heart replacement.                      " DM