MATTHEW POYNTER was such a lively, happy baby that the management of Harefield hospital in west London chose to feature him in a promotional video to raise funds. Matthew, then just one year old, was filmed to the strains of the pop star Sting singing Every Breath You Take.

His parents treasure that video. It is the only one that exists of Matthew when he was a normal child. Not long after it was made he was given a new heart by Sir Magdi Yacoub, the world-renowned surgeon. He came out of the operation irreversibly brain-damaged.

The Poynters are not claiming anyone was medically negligent but that Yacoub and his team at Harefield failed to tell them of the risk of brain damage associated with the particular difficulties of open-heart surgery. In April they will seek damages in the High Court. They claim doctors did not warn them because surgical staff had already decided to go ahead with the operation. Yacoub’s team, they allege, was fully aware of their fears and unease about the surgery.

It is understood that Harefield hospital has conceded that its doctors did not warn them in advance. It argues there was no need to do so because the surgical team was better placed than the parents to judge what was best for Matthew.

His mother and father insist that if they had known of the risk they would not have allowed the operation to go ahead and would rather their son had died with dignity.

“Many people will find it difficult to understand,” said Kevin Poynter, an osteopath from Biggleswade, Bedfordshire. “We love Matthew and we knew that without the transplant he would die. But the way he was going was peaceful. We were told the transplant would only give a few more months or years. This was the choice: a high-tech death delayed for a while or a quiet passing away. If they had told us about any risk of brain damage we would have said no to the operation.”

Tom Osborne, the family’s solicitor, said the courts should back the right of parents to decide the fate of their child. “If the parent is responsible, it must be their decision to let a child live or die. This is life-threatening surgery. If the child survives but is brain-damaged there are consequences for the whole family. This family was not given enough information to make an informed decision.” He said he would call on expert witnesses to confirm that the risk of brain damage in heart surgery is well known and that patients are usually informed.

Matthew was born a healthy child. When he was eight months old he caught a virus that infected the muscle of his heart. At first he did not seem ill, but he had a cold which would not go away and his mother suspected something was wrong. Their GP referred them to the local hospital, where they were introduced to the idea that Matthew could be fatally ill and that his only option was a heart transplant.

“The doctor told us that in all likelihood he was going to die,” said Kevin Poynter. “Then they talked about transplant but right away I said no. No way.”

The Poynters were soon sent on to Harefield and their son was put into the surgical care of Yacoub. However, they continued to refuse to consider a transplant.

“I have always had reservations about transplants,” said Linda Poynter. “I don’t believe in life at any cost. The quality of life is more important than the quantity.”

She alleges that none of the doctors was prepared to discuss these concerns. “I just wanted to talk to somebody, but none of Yacoub’s doctors talked to us as much as we felt they should. I kept thinking, ‘When is Yacoub going to talk to us about this? He never did. I think we wanted to convince ourselves that we would be doing the right thing by agreeing to the transplant.”

The Poynters allege that one member of the transplant unit’s staff told them that if they continued to refuse the treatment, the hospital would obtain a court order.

Despite the parents’ reluc tance, Matthew was put on the transplant list. When a donor heart became available, they agreed to the operation. “We were told Matthew was going to die anyway, that the operation would extend his life for a few months. We could not deny him that extra time,” said Kevin Poynter.

The Poynters allege they were warned there was a risk that the operation might kill him but not that he could be brain-damaged as a result.

The operation itself was deeply traumatic. His mother carried Matthew down to the operating theatre where he was taken from her by a nurse. “It is imprinted in my mind for ever, his looking over the shoulder of the nurse and reaching out for us, screaming,” she said.

After the operation, Linda Poynter approached Yacoub as he was leaving the theatre. “He just said he was very sorry. I immediately thought Matthew must have died. He said that he was worried about organ damage. I thought he would come and explain what he meant. But we never saw him again.” Several months later it was confirmed that Matthew would not recover from the brain damage and would need lifelong nursing care. Now aged 10, he is incapable of doing anything for himself. He can move his head a little, can see bright lights and laugh and cry. But he cannot communicate in any other way and is constantly curled by body spasm into a ball.

The Poynters decided to sue the hospital when they were told by other doctors that they should have been told of the risk of brain damage.

In 1992, five years after Matthew’s operation, Rose Fleet, then eight years old, underwent heart surgery at Harefield and she, too, emerged with severe brain damage. Her parents have been granted legal aid to claim damages against the hospital. Polly Fleet, Rose’s mother, said last week she had not been told of possible brain damage.

Yacoub spoke to the family nine days after the operation. “He was adamant that everything had gone well and he could not understand the brain damage,” Fleet said. “If I had been told there was a risk of such severe brain damage, I would have said no. I would rather she had died the happy, chatty girl I remember. I was denied the right to make that decision.”