Dr. Gaynor is an attending cardiothoracic surgeon at The Children's Hospital of Philadelphia and assistant professor of surgery at the University of Pennsylvania School of Medicine. He received his medical degree at the Medical University of South Carolina, then completed general and cardiothoracic surgery residencies at Parkland Memorial Hospital and Duke University Medical Center. He completed the congenital cardiac surgery fellowship at the Hospital for Sick Children, Great Ormond Street in London. He received his appointment at The Children's Hospital of Philadelphia in 1995.
Dr. Gaynor performs the full range of reconstructive congenital operations, as well as cardiothoracic transplantation. He coordinates the program in extracorporeal membrane oxygenation (ECMO). He successfully performed heart transplantation on a child following 44 days of support with ECMO, a record duration preceding transplantation. Dr. Gaynor is also organizing the Division of Cardiothoracic Surgery's implantable ventricular assist device (VAD) program. He specializes in the analyses of clinical case series, utilizing the large case rate at Children's Hospital to understand the nature and variety of congenital cardiac and thoracic lesions and determine the effectiveness of surgical intervention.
In the laboratory, Drs. Gaynor and Spray are investigating the early stages of pulmonary vascular obstructive disease, a complication of many congenital cardiac anomalies. Specifically, they are studying early endothelial cell alterations in the expression of factors that influence pulmonary vascular tone. Dr. Gaynor is also an authority on the measurement of intrinsic left ventricular contractility.