Sefeena Begum: Died after a straightforward operation

In August 1999 two-year-old Sefeena Begum, from Aylesbury, was admitted to the centre for routine surgery to correct a hole in the heart. She died.

A confidential hospital inquiry was launched without the knowledge of the Sefeena's parents.

It found that heat from the lights in the operating theatre had contributed to her death.

But her family was never told anything about the finding.

Neither was Oxfordshire coroner Nicholas Gardiner.

Irene Godfrey: Opened four times by junior doctors

He has since decided to re-open the case.

In a written statement he says: "In the light of allegations brought to my attention I am investigating the death of Sefeena Begum in August 1999".

Irene Godfrey was admitted to the centre for a valve replacement in September 1999.

After surgery it became clear there was excessive bleeding.

A swab had been left inside Ms Godfrey and she was opened up four times by junior doctors.

She died in the early hours of 6 October last year.

Her relatives say they were not told this information or about an instruction not to resuscitate her.

David Highton: "I would want to apologise"

John Radcliffe's recently-appointed chief executive David Highton says he is sorry if relatives feel they have not been given the right information.

But he pointed out that there is no problem with the overall results of surgery at the heart centre.

"Firstly I would want to apologise if the actions of the hospital have caused so many distress needlessly," he told BBC News 24.

"I would want to be sure that we shared with them all relevant information, relevant to the care of their relatives."