Fifty years ago half of all children who were born with congenital heart defects died before their first birthday. Now, 90% survive for at least a year. As heart defects are the commonest of all congenital defects, the impact of this advance is enormous. Professor Catherine Neill, British-trained, but based primarily at Johns Hopkins University school of medicine, Baltimore, who has died at the age of 84, played a major role in this turnaround.
Working at a time when open-heart surgery was in its infancy, she identified syndromes and made major discoveries in the aetiology - the study of the causes - and genetics of heart defects. These anticipated current research by decades. She developed diagnostic techniques and followed up her patients into later life, showing the long-term outcome of conditions after they became curable.
The scimitar syndrome, named after its appearance on x-ray, where blood from the lungs drains into the wrong side of the heart, was her discovery, in 1960. She established its genetic basis, and gave parents gentle and unambiguous explanations of their child's condition. She published, with Drs Edward and Carleen Clark, a book for parents, The Heart of a Child (1992), which is still regarded as the best of its kind. When her career started, it was difficult for women to advance in medicine, and her work made life easier for the women who followed her.
Catherine Neill was born in Highgate, north London, the daughter of Sir Thomas Neill, who pioneered the introduction of national health insurance in 1911. From Channing school, Highgate, she went to the Royal Free Hospital medical school, north London, in 1938, qualifying in 1944. She worked at the Royal Free Hospital for a year as house physician and house surgeon. From 1945 to 1950 she was house physician and then registrar at the Queen Elizabeth hospital for children in Hackney, east London, taking a year out to do similar work in Stoke-on-Trent. She was awarded the diploma in child health, the postgraduate qualification for paediatricians, in 1946. It was at this stage in her career that she became interested in congenital heart defects.
In 1950 she went on a one-year research fellowship to the Hospital for Sick Children in Toronto, followed by a similar fellowship at Johns Hopkins hospital. She went, initially, for one year, and stayed for three, till 1954. She came back to the Queen Elizabeth hospital for a further two years, and then returned to Johns Hopkins for the rest of her life. This was the world's leading centre for the treatment of previously lethal congenital heart defects, and there she was tutored by, and assisted, one of the great pioneers of children's cardiology, Helen Taussig. Taussig, who trailblazed open-heart surgery for babies, said of her, "she was among the ablest I have trained".
Neill was not a surgeon but a diagnostician, and she was a marvellous teacher with a wonderful bedside manner. The rest of her career was spent at Johns Hopkins, where she was appointed professor in 1964. She did important work on the aetiology of coronary heart disease in adults, a disease that has its origins in childhood. As co-director of the Baltimore Washington infant study, she analysed the genetic and environmental factors of malformations in 5000 infants. This laid the groundwork for current genetic counselling, foetal assessment and maternal care.
She was the author of The Developing Heart: a "History" of Pediatric Cardiology (1995), 40 book chapters and 100 papers in learned journals.
Catherine Neill was kind, modest and empathetic almost to a fault. Peter Rowe, paediatrics professor at Johns Hopkins, described her as a generous friend, "but none of us knew how generous she was to others because she kept quiet about any altruistic endeavours she undertook inside or outside the hospital".
She returned to Britain frequently to visit her family. Her last visit was to a family party in January. She had advanced cancer, and died in a Wimbledon care home six weeks later. She is survived by her three brothers, of whom Sir Brian is a former appeal court judge and Patrick, Lord Neill, a former chairman of the committee on standards in public life.
· Catherine Annie Neill, paediatric cardiologist, born September 3 1921; died February 23 2006
