The University has developed a three-dimensional "virtual" heart which is so sophisticated that it can be used for research – making the use of animal hearts obsolete.

Currently animals such as dogs, rabbits, goats, rodents and pigs are used for the research. New heart drugs are often tested on animals whose hearts have been deliberately made to beat erratically or abnormally by implanted electrical pacers.

At the end of the experiments, the animals are killed and their hearts removed.

The virtual heart, pictured, was developed by non-animal research charity at the university, the Dr Hadwen Trust.

The model has already been used to simulate the effects of a commonly used heart drug (lidocaine), and the results have revealed how one of the side effects of the drug occurs.

The trust says the 3-D heart tissues have also been causing a stir at scientific conferences in Belgium, Germany, the Netherlands, Switzerland and the USA.

Wendy Higgins of the Dr Hadwen Trust said: "Our cutting-edge 3-D human heart proves that we don't have to harm animals to benefit from medical progress. In fact we can get better results if we invest in modern, humane techniques like those being pioneered at Leeds."