As he gives evidence this week at the Bristol Royal Infirmary inquiry, BBC News Online profiles the man at the centre of the scandal

There are few people who have ambiguous feelings about James Wisheart, whether among his former patients, or the medical profession at large.

He has been part demonised, and part eulogised, labelled both as an arrogant and callous doctor, and as caring, dedicated and skilled.

Even the General Medical Council panel which ended his career in shame last year commented that there was no evidence that he had acted with anything but the best intentions for his patients.

Mr Wisheart, born the son of a Methodist preacher in Enniskillen, Northern Ireland, remains a member of that church.

He embarked on his medical career at Queen's University, Belfast in the late 1950s, and only reached Bristol Royal Infirmary as a cardiothoracic surgeon in 1975.

At that time he was undeniably at the leading edge of his profession.

In 1976 he performed a radical pig heart valve transplant into teenager Sue Gale - and 20 years later she returned to testify on his behalf at the GMC, as a mother-of-two sons.

She is set to enter the record books as the patient with the longest-lasting valve of its type in the world.

She said later: "Mr Wisheart is my hero. He is a marvellous man. I have never known a man with such patience and understanding."

By 1992 he became medical director of the newly-formed United Bristol Healthcare Trust, which absorbed the old infirmary and children's hospital.

By 1995 the scandal had broken.

Praise and condemnation

While the praise of people like Sue Gale prompted the formation of the Bristol Surgeon's Support Group, many more voices were raised in condemnation from the Bristol Heart Babies' Action Group.

These parents, who had all lost their children, or watched them suffer enormous brain damage at Bristol Royal Infirmary, are resolute that Wisheart presided over a department either incapable or unwilling to know when to stop.

They say that the fear of de-designation as a specialist centre for paediatric cardiac surgery, and the inevitable financial cost this would invoke, were the driving forces behind an inability on the part of both surgeons, and their chief executive, to recognise their weaknesses.

Certainly the detailed examination of paediatric cases by the inquiry's own experts reveal that in at least one case, the speed at which the surgeon carried out the procedure may have had a bad effect on the outcome.

But there are others who maintain that Mr Wisheart recognised some of the organisational weaknesses at Bristol, and devoted time to trying to recruit a new surgeon and improve facilities.

Mr Wisheart, who is now 60, took retirement as the GMC hearing progressed, and has been described as "a broken man".

It now seems unlikely, regardless of the outcome of the inquiry, that he will be remembered for his pioneering work in heart surgery in the 1970s and early 1980s.

He conceded as much this week, when asked if he had retired with pride in his surgical record.

He said: "I was very disappointed at the manner in which my professional career had ended.

"I felt my surgical skills had achieved a great deal but it was clear some aspects of those skills were under criticism."