The 52-year-old star had surgery without general anaesthetic on Friday after tests revealed he had an irregular heartbeat.

John Barrett, the charge nurse managing the cardiac floor of Wellington Hospital in north London, said Sir Elton was fine and there were no problems with the operation.

"I would expect no complications. The procedure is very simple and less than 1% of patients get a complication."

Sir Elton: "Thank God for the British medical system"

Mr Barrett said Sir Elton must rest to allow the wires attached to the pacemaker to become embedded inside his heart.

General movements, even those as simple as brushing your hair could dislodge the wires, he added.

And he said Sir Elton would not have been completely unconscious during the operation. "Patients are not given a general anaesthetic - they are normally given a local one and then given a valium-type drug that puts them in semi-unconscious state."

An incision would have been made in the left side of the chest before wires were inserted into the heart. The wires are then attached to the pacemaker which is controlled by a computer.

Sir Elton described the operation in which his pacemaker was fitted: "I was unconscious for an hour-and-a-half and woke up for the end of the operation."

The life expectancy of a pacemaker is between eight and 10 years.