Surgeons at the Alfred Hospital in Melbourne have successfully completed initial animal implant trials of an "artificial heart" being developed by engineers at UTS in conjunction with Australian medical device manufacturer Micromedical Industries Limited (MMI).

The animal implants are the first full system test of the device, which is designed to take over the pumping function of the human heart's left ventricle when it is severely weakened by disease.

Worldwide, about 4,000 "pulsatile" pumps have been implanted in humans, including more than 30 Alfred Hospital patients, to treat heart disease. These pumps act as a temporary solution, taking over the function of the patient's left ventricle to restore normal levels of cardiovascular activity until a donor organ becomes available.

While the medical profession is now eager to use such VADs (ventricular assist devices) as an alternative to transplant surgery, enthusiasm has been dampened by the limitations of the existing pulsatile pumps, which are large, expensive and inefficient.

As a result, university research teams and major medical manufacturers throughout the world are attempting to develop a smaller continuous-flow rotary blood pump as an alternative to the pulsatile pumps.

In Australia, UTS and MMI began research on such a device in January 1997, aided by an Australian Research Council Collaborative Grant. The research team now consists of 14 engineers and scientists, including some from the University of NSW, whose expertise covers a broad range of fields, including fluid dynamics, electromagnetics, electronics, control engineering, materials technology, and haematology.

Senior Research Fellow in the UTS Faculty of Engineering, Dr Peter Watterson, said that unlike a conventional rotary pump, characterised by an impeller and a motor separated by a sealed shaft, the new prototype uniquely combines the impeller and motor.

"This eliminates the seal and conventional bearings that could cause serious side effects for patients due to blood damage and blood clotting," Dr Watterson explained.

The CEO of Micromedical Industries, Dr John Woodard, described the results of the early animal tests as "very encouraging", but said long-term testing was needed to ensure its reliable use by the first human, currently scheduled for early 2001.

UTS's Professor Vic Ramsden says currently around 44 per cent of all deaths in Australia each year are directly related to heart disease. Of these, around 750 people die from congestive heart failure and they could be helped by the pump. "It is estimated that the number of cases of congestive heart failure in which this device could be used is 70,000 per annum worldwide," he said.