Maude Abbott
Maude Elizabeth Seymour Abbott (March 18, 1869-1940) was a Canadian pediatrician and cardiologist.  Abbott was one of the first experts in congenital heart disease. Many people considered her the top expert in the world during her lifetime. She studied and documented the hearts from cyanotic patients. Abbott developed the international classification system for congenital heart disease. She recorded it in her Atlas of Congenital Heart Disease.  Her work made it possible for medical researchers to start treating heart disease in the later Twentieth century.