The pump is placed inside a failing heart

Before the operation, Mr Houghton had been given just weeks to live.

But, according to his doctors, the operation was a success and Mr Houghton is recovering well.

He was admitted to hospital earlier this week for checks, but according to his doctors he remains in excellent health.

The Jarvik 2000 was fitted during a 14-hour operation.

It is attached to the left ventricle of the heart - the chamber that gives the heart most of its pumping power when it contracts.

A power cable that supplies electricity to the pump comes out of the chest and up the neck of patient and out through the skull.

The wires then lead down to a battery pack worn on the patient's waist.

Cardiac surgeon Stephen Westaby, who carried out the operation said: "The pump takes blood out of the heart and pumps it around the body."

Within six weeks, Mr Houghton's heart and liver functions had improved as had his ability to exercise.

His blood pressure dropped and there was only negligible damage to blood cells from the pump.

Mr Houghton changes the speed of his pump manually depending on how much exercise he is taking.

The batteries, which are rechargeable, need to be changed every eight hours.

Wires powering the pump are brought out of the head

The pump replaces a much larger pump that was so cumbersome it could only be left inside a patient for a few months.

Heart surgeons believe the new pump could be a solution to the chronic shortage of hearts available for transplantation.

"Currently the outlook is dismal for patients with end-stage heart failure who are not eligible for transplantation," Mr Westaby said in The Lancet.

"Our laboratory experience and encouraging first clinical intervention with this small, silent intraventricular device suggests a potential alternative for many patients."

The research is published in the medical journal The Lancet.