The review, part of the public inquiry ordered after the hospital was found to have an unusually high death rate in some operations, is being carried out by 35 specialists who have volunteered their services.

They are to look at the case notes and speak to the families of the 80 to try and work out why results at the hospital were so poor.

Public hearings, which heard evidence from, among others, senior figures at the hospital, the Royal College of Surgeons and Department of Health, have been suspended for the summer.

Janardan Dhasmana was banned from operating on children

More than 1,800 heart operations on children were carried out at Bristol during the 12 years to 1995, but the inquiry is confident that closely examining only 80 cases will be sufficient.

A spokeswoman said: "The review teams will look at the adequacy of key aspects of pre-operative, surgical, and post-operative care, as well as the adequacy of care overall."

All the families of the children involved in the cases will be contacted and asked in confidence for their comments on the standard of care they felt they received.

Finding where the blame lies

The inquiry wants to find out whether main responsibility for the poor surgical outcomes rests with the surgeons, Mr James Wisheart and Mr Janardan Dhasmana, or whether the situation in which they were working had any bearing.

Mr Wisheart, along with hospital manager Dr John Roylance, was struck off by the General Medical Council (GMC), the doctors' disciplinary body, who said he should have realised that Bristol was achieving bad results and stopped operating.

Mr Dhasmana was banned from operating on children or babies for three years.

The GMC case dealt with only a small number of cases in which babies died followed heart surgery at Bristol.

The mammoth, multi-million pound inquiry, ordered by Secretary of State for Health Frank Dobson after the GMC case finished last year, has already received 100 statements from families of babies operated on at Bristol.