Parents of children who died or were severely injured after undergoing heart surgery at Bristol Royal Infirmary yesterday called for a public inquiry after the General Medical Council ruled that the cases against three doctors at the hospital were proven.

Consultant heart surgeons James Wisheart, 59, and Janardan Dhasmana, 58, and Dr John Roylance, 67, former chief executive of the United Bristol Healthcare NHS Trust, now face the prospect of being found guilty of serious professional misconduct and struck off the medical register.

The case, the biggest medical disciplinary inquiry, centres on 53 heart operations on babies and children between 1988 and 1995. The inquiry heard 29 of them died and four suffered brain damage.

Mrs Helen Rickard, whose 11-month-old daughter Samantha died after a heart operation performed by the surgeon, walked alongside his taxi saying ''bastard'' and ''rot in hell'' as Mr Wisheart and his wife were escorted from the GMC headquarters by police.

The GMC ruled that Mr Wisheart, of Westbury on Trym, Bristol, who is now retired, and Mr Dhasmana continued operating on children despite their poor success rate and without sufficient regard to the safety and best interests of their patients.

Mr Wisheart also failed to tell parents the true risks of putting a child in his hands for surgery, the GMC's disciplinary committee in London found.

It also found Dr Roylance, of Brentry, Bristol, failed to stop the surgeons operating even when colleagues made clear their concerns about the number of children who had died.

The GMC will rule next month if these facts amount to serious professional misconduct.

After the ruling, parents of some of the children who died following heart operations performed by the two surgeons said the investigation did not go far enough and called for a public inquiry. They claim many more children died as a result of the doctors' actions.

Mrs Rickard, whose husband Andy committed suicide two years after their daughter's death, said: ''The scope of the GMC inquiry was not wide enough. There is still a lot more to be investigated in this case. This is just the tip of the iceberg. There are about 91 other people who have had children involved in these operations. We need a public inquiry.''

Her daughter underwent a heart operation in 1993 but never recovered.

Mrs Rickard said: ''Mr Wisheart told me the survival rate for her operation was 75%. I found out later that the mortality rate was around 60%. We were totally misled about the risks.''

Mr Malcolm Curnow, who heads the Bristol Heart Children Action Group, said: ''It is evident that there are many more serious questions that have yet to be asked.''

Mr Curnow's six-month-old son Jordan died after a heart operation in 1993.

The 65-day hearing, which started last October, has become the biggest in the history of the GMC.

Sixty-seven witnesses gave evidence and the hearing is estimated to have cost the GMC #2.2m.

There will now be an independent inquiry by the Government but its type, who will chair it and its terms of reference have yet to be decided.

Mr Wisheart, who became medical director of the United Bristol Healthcare NHS Trust in 1992, carried out 15 hole-in-the-heart operations on children between 1990 and 1994. Nine of them died.

The inquiry had heard that nearly two in three of Mr Wisheart's patients died compared with the national average of one in seven.

The disciplinary committee ruled that by May 1993, when Mr Wisheart had performed 12 operations on children, half of whom had died, he should have been aware of the high mortality rate in his operations.

But Mr Wisheart went ahead with three more operations on children, all of whom died.

The GMC ruled that he performed these three operations despite the previous poor results, without examining his own performance as a surgeon, without seeking adequate retraining or advice, and without paying sufficient regard to the children's safety and best interests.

In two of the operations, he went ahead with surgery despite concerns voiced on several occasions by colleagues.

He also misled the two families about the risks of surgery and his ability to perform the operation, the GMC found. Mr Wisheart also allowed Mr Dhasmana to go ahead with an operation in 1994 on Joshua Loveday despite concerns from colleagues. Joshua died.

Mr Dhasmana, who joined the BRI in 1986, carried out 38 ''switch'' operations on children - to correct back to front hearts by changing over the aorta and pulmonary artery - between 1988 and 1995. Twenty of them died.

The inquiry heard that children and babies who underwent surgery performed by Mr Dhasmana had a two in three chance of dying compared with one in 10 nationally.

The GMC ruled that he carried out two operations on newborn babies in 1993 despite previous bad results, without examining his own performance as a surgeon, without seeking adequate retraining or advice, and without paying sufficient regard to the children's safety and best interests.

The disciplinary committee also found that Mr Roylance allowed both doctors to continue operating despite concerns voiced on five occasions and failed to stop the operation on Joshua Loveday.

Consultant anaesthetist Steve Bolsin started working at Bristol Royal Infirmary in 1988 and he soon noticed a problem with children's heart surgery: too many were dying.

Nine years later, three doctors appeared before the General Medical Council charged with serious professional misconduct.

The two surgeons, James Wisheart and Janardan Dhasmana, performed 53 operations on children between 1988 and 1995: 29 of the children died, and four suffered serious brain damage.

Between 1990 and 1995, some medical professionals at the Bristol Royal Infirmary became increasingly worried about the number of babies and toddlers dying in the operating theatre or shortly after operations by Mr Wisheart, now retired, and Mr Dhasmana.

Between 1990 and 1994, Mr Wisheart, who was appointed medical director of the hospital in 1992, performed 15 operations on children to repair holes in their hearts. Nine of them died.

Babies operated on by Mr Wisheart had a 50% chance of survival compared with the national average of just over 83%, the inquiry heard.

Dr Bolsin, 44, became so concerned about the high death rates that he wrote to Dr John Roylance in the summer of 1990, and, eventually, to the Department of Health.

Mr Wisheart said he was never told of Dr Bolsin's concerns in 1990. The first time he saw the letter was in 1995, at around the time of a Dispatches documentary for Channel 4 which exposed the problems at Bristol Royal Infirmary.

Professor Gianni Angelini, 44, professor of anaesthetics at Bristol University, also raised concerns.

He said he spent nearly 18 months trying to alert senior surgeons and the hospital's chief executive to the unacceptably high mortality rates.

The matter came to a head in January 1995, when an arterial switch operation, to correct a hole in the heart, was planned for 18-month-old Joshua Loveday.

Professor Angelini, Dr Bolsin and the Department of Health advised against the operation.

But Mr Dhasmana operated. Joshua died in the operating theatre.