After leaving the military, Mullins came to Texas Children's Hospital (TCH) and Baylor College of Medicine.[1] He was the first director of the pediatric intensive care unit at TCH.[2] Mullins became known for his work with cardiac catheterization. Before Mullins' work, catheterization labs had been primarily used to image the heart. Mullins worked to advance interventional cardiology, using cardiac catheterization to repair heart defects. University of Chicago cardiologist Ziyad Hijazi said that Mullins is "the father of modern interventional pediatric cardiology".[1] Mullins created a sheath and introducer system for carrying out cardiac catheterization and he pioneered the use of endovascular stents to treat children with heart defects.[3][4] In late 2005, Mullins performed his last cardiac catheterization procedure. He retired in 2006.[1]
Mullins authored Cardiac Catheterization in Congenital Heart Disease: Pediatric and Adult in 2006. The book was reviewed in the journal Circulation.[5]
The American Academy of Pediatrics Section on Cardiology and Cardiac Surgery gave Mullins its Founders Award in 2004.[6] The cardiac catheterization lab at TCH is named for Mullins.[7] The Society for Cardiovascular Angiography and Interventions has established the Mullins Lecture, which is the keynote address at the organization's annual scientific sessions.[8]
