'Well, I'd tell them that It's worth it. If there's no alternative - they either die, or they have it done.' (Barney Clark)

A little less than a year ago, Dr Barney Clark became the recipient of the world's first permanent, totally artificial heart. Thanks to that case, Clark, an unknown 61-year-old dentist, and Dr William DeVries, a little known surgeon, are world-famous.

This documentary uses last year's events in Salt Lake City as the framework for a detailed account of artificial heart research in general. Some of the key surgeons and scientists, in Salt Lake City and elsewhere in the USA, open up their laboratories to "Horizon", discuss the technical, ethical and political problems surrounding the artificial heart and admit that many of them are yet to be solved. Barney Clark survived for just three months with his man-made heart; did his operation open up a new future for heart surgery - or set it on a wrong course?

Narrator PAUL VAUGHAN
Written and produced by STUART BARRI
Horizon editor GRAHAM MASSBEY