My friend Charles Ilsley, who has died aged 74 of pancreatic cancer, was a cardiologist and a pioneer in the field of angioplasty – widening arteries to allow blood to flow more freely to the heart. As clinical director at Harefield hospital in the London borough of Hillingdon, he developed a 24-hour primary angioplasty service for treating heart attack patients.

After studying medicine at St Mary’s hospital, London (1968-73), Charles worked as registrar for Stanley Peart who suggested that he should go into cardiology. At that time interventional cardiology was in its infancy. In 1977 he first went to Harefield as a registrar in cardiology, then moved to the National Heart hospital for a period of research with Tony Rickards, who, in 1980, assisted by Charles, performed the first balloon angioplasty in London.