Extra heart surgeons are being recruited at Oxford's John Radcliffe Hospital because it has too few to train junior staff properly.

The world-famous Oxford Heart Centre has lost its seal of approval as a top trainer of would-be heart surgeons because staff were too stretched to supervise juniors adequately.

The decision came as a bitter blow for the centre, which employs leading cardiac surgeon Stephen Westaby and is respected as a teaching hospital.

Mr Westaby has spent a decade campaigning for improvements to heart treatment and as far back as 1987 pioneered plans for the £4.1m heart centre.

Now the John Radcliffe is to employ two extra cardiac surgeons to ease the burden, boosting the number at the centre to five. The hospital is also looking to open up a third cardiac theatre. The changes are expected to help cut waiting times for operations.

The national Specialist Advisory Committee, which reviews training programmes for specialist registrars, revoked the centre's accreditation in July.

The hospital will have to improve its training before the committee restores it, although programmes are still in place.

A spokesman for the Oxford Radcliffe Hospitals NHS Trust said: "The SAC visit hospitals and specialists all over the country checking that proper programmes are in place.

"Our accreditation was taken away in July. It is not what we would have wished but it is not an issue of quality of service." The spokesman said the trust had immediately put various steps in place to have the accreditation re-instated.

She said: "The main issue was to do with the number of surgeons and their capacity to undertake the training. We put various steps in place and two more cardiac surgeons are going to be appointed."

The spokesman said the SAC looked at the way training programmes were run, ensuring juniors are not allowed to operate unsupervised. It also makes sure juniors have sufficient experience of operating theatres and receive fixed teaching sessions.

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