He was internationally known for his contributions to pediatric cardiology education and the pathology of congenital heart disease.
He then served as a lieutenant commander and pediatric cardiologist in the United States Navy in San Diego.
[1] Upon completion of his service, he did an additional fellowship in cardiac pathology at Children's Hospital Boston and Harvard Medical School, studying under Drs.
In 1977, he returned to the University of Pennsylvania and The Children's Hospital of Philadelphia, where he worked until his retirement in 2017.
He helped develop a consensus between the two main approaches to the nomenclature of congenital heart disease (that proposed by the Van Praaghs and himself and that proposed by Robert Anderson), which led to The International Paediatric and Congenital Cardiac Code.