Joystick and keyboard are replacing a steady hand with a scalpel for tricky heart operations, cutting complications and recovery times.

The latest technology uses tiny remote-controlled robot pincers to carry out procedures which previously would have required the complete opening of the chest cavity.

Not only are the mechanical "hands" steadier than those of even the most skilled surgeon, but they allow the heart to be reached through only a tiny incision.

The technology was used to replace the heart valves of six dogs in experiments carried out by Dr Eugene Grossi and a team from New York University School of Medicine.

Thousands of patients with faulty heart valves could benefit each year from the technique.

The robot hands could also be used in future to help with heart bypass operations.

The results of the dog study were presented at the Society of Thoracic Surgeons' annual meeting in Fort Lauderdale, Florida.

Remote console

The procedure uses an inserted probe to produce a live picture of the heart and its surroundings, and, seated at a console with a joystick, uses this to guide the robot hands to the correct point.

They have been inserted through a hole only an inch and a half wide next to the ribcage.

Dr Grossi was full of praise for the Zeus Robotic System.

"It removes tremors and it allows us a beautiful, unobstructed view of what we're doing," he said.

"Instead of making a big hole in the chest we look through instruments."

Established heart surgery procedures involve cutting through the patient's breastbone and spreading the ribs to expose the heart.

The smaller incision takes no longer, far less time to heal and leaves a smaller scar.

It would save money by reducing the amount of time patients would have to spend in hospital recuperating after an operation.

The robots themselves could well be too expensive for widespread use in the UK's National Health Service.