 Stelzer's report on the Ross procedure, co-authored with Susanne Weinrauch and Robert F. Tranbaugh and published in 1997 in the Journal of Thoracic and Cardiovascular Surgery, has been cited in over 20 medical publications across the globe.Stelzer's experience with aortic valve replacement also extends to homograft, stentless porcine, and implantations of mechanical valves, and in 1999 he was awarded a U.S. patent for his minimally invasive endoscope.Past hospital positions have included Chief of Thoracic Surgery at the Oklahoma Memorial Hospital and Chief of Cardiothoracic Surgery at St. Luke's-Roosevelt Hospital Center in New York.