Doctors at the Diana Princess of Wales Children's Hospital, Birmingham, fitted the device to Katie Burke in a minor surgical operation when she was just three weeks old.

Katie's mother Sue: "There's a long piece of wire curled up inside her"

Katie, whose twin sister Joanna was born without complications, was diagnosed as having a complex heart condition during her mother's pregnancy and was first operated on just hours after her birth.

That surgery was followed up with the fitting of a specially-configured pacemaker, the size of a 50p piece, which was inserted under her left armpit.

Simplified operation

Consultant paediatric cardiologist Joseph De Giovanni, who fitted the device, said the procedure was a success.

"We are very happy in that we have managed to simplify the way we do the operation," he said.

"Normally we would have needed to operate to put the pacemaker inside. But this time we have been able to do it without opening up the chest," he said.

Pacemakers can be fitted to patients with an irregular or no heartbeat and are usually placed in the chest cavity, in a relatively minor operation under general anaesthetic.

The devices regulate the beat by sending an electrical charge from a tiny lithium battery down a wire to the heart muscle.

Novel idea

Mr De Giovanni said that although they had not opened up Katie's chest, "obviously it is still difficult in a child of this size because the veins are very small and there is not much room to put the pacemaker".

Katie's mother, Mrs Sue Burke, 36, from Stechford, Birmingham, said: "I was shocked when we were told she needed a pacemaker.

"Although we knew she needed treatment for heart problems no-one considered a pacemaker for a baby.

"It has saved her life."

Mrs Burke, added: "We just feel immense relief that they had the technology to do this.