The doctors' professional body will decide if heart surgeons James Wisheart and Janardan Dhasmana, and Dr John Roylance, former chief executive of the United Bristol Healthcare NHS Trust, are guilty of serious professional misconduct.
The GMC's disciplinary committee will decide whether the doctors should be struck off after hearing evidence about 53 operations on babies and toddlers between 1988 and 1995. Twenty-nine died and four suffered serious brain damage.
Mr Wisheart, 59, of Bristol, now retired, and Mr Dhasmana, 58, are accused of carrying out heart operations on children beyond their clinical competence at Bristol Royal Infirmary despite warnings that at least twice as many babies died in their care as in other hospitals.
They are also charged with failing to tell parents the true risks of putting a child in their hands for surgery.
Dr Roylance, 67, of Bristol, is charged with failing to stop the surgeons operating, even when colleagues made clear their concerns about the number of children who had died.
All three deny the charges.
The GMC panel, which retired to consider its verdict last Friday, must confine itself to ethical issues such as what the parents were told about the risks of surgery and at what point the surgeons should have realised the mortality rate was above the national average.
If found guilty, the doctors could be admonished, conditions could be put on their registration or they could be struck off the medical register.Reuse content