Karl Degenhardt, MD, PhD, is an attending cardiologist with the Cardiac Center and Fetal Heart Program at Children's Hospital of Philadelphia.

Despite having many responsibilities, Dr. Degenhardt says that, ultimately, he has two primary jobs. “One is to make an accurate assessment of the patient’s conditions and come up with the best plan for management. The second is to be sure that the patient and family understand what I am thinking and why I am making my recommendations.”

His decision to pursue pediatric cardiology was made at the Mount Sinai School of Medicine, where he completed his MD and PhD. He explains, “I know it sounds nerdy, but for me, the relationship between the anatomy of the heart and its function in the patient’s overall cardiovascular system just had a logical appeal.”

Looking to the future, Dr. Degenhardt talked about the role patient feedback is playing in the evolution of pediatric cardiology. “The population of patients surviving with congenital heart disease is growing exponentially,” he says. “These patients are teaching us what to expect and how to help the next generation.”

Education and Training

Medical School

MD - Mount Sinai School of Medicine, New York, NY


Pediatrics - Schneider Children’s Hospital, New Hyde Park, NY


Pediatric Cardiology - The Children's Hospital of Philadelphia, Philadelphia, PA

Board Certification

Pediatric Cardiology – American Board of Pediatrics
Pediatrics – American Board of Pediatrics

Graduate Degree

PhD - Mount Sinai School of Medicine, New York, NY

Titles and Academic Titles

Attending Cardiologist

Assistant Professor of Pediatrics, Perelman School of Medicine at the University of Pennsylvania

Departments and Services




Aghajanian H, Cho YK, Rizen NW, Wang Q, Li L, Degenhardt K, Jain R: Pdgfrα functions in endothelial-derived cells to regulate neural crest cells and development of the great arteries. Dis Model Mech Jul 2017.


Saul D, Degenhardt K, Iyoob S, Johnson A, Surrey L, Johnson M, Rychik J, Victoria T: Hypoplastic Left Heart Syndrome and the Nutmeg Lung Pattern in Utero: A Cause and Effect Relationship or Prognostic Indicator? Pediatr Radiol 46(4): 483-9, Apr 2016 Notes: Accepted. Notes: *Co-first author with equal contribution

Aghajanian H, Cho YK, Manderfield LJ, Herling MR, Gupta M, Ho VC, Li L,Degenhardt K, Aharonov A, Tzahor E, Epstein JA: Coronary vasculature patterning requires a novel endothelial ErbB2 holoreceptor. Nat Commun 30(7): 12038, Jun 2016.


Chen D, Wang X, Liang D, Gordon J, Mittal A, Manley N, Degenhardt K, Astrof S: Fibronectin signals through integrin α5β1 to regulate cardiovascular development in a cell type-specific manner. Dev Biol 407(2): 195-210, Nov 2015.


Channing A, Szwast A, Natarajan S, Degenhardt K, Tian Z, Rychik J: Maternal Hyperoxygenation improves left heart filling in the fetus with atrial septal aneurysm causing impediment to left ventricular inflow. Ultrasound Obstet Gynecol 45(6): 630, Jun 2014.

Liang D, Wang X, Mittal A, Dhiman S, Hou SY, Degenhardt K, Astrof S: Mesodermal expression of integrin α5β1 regulates neural crest development and cardiovascular morphogenesis. Dev Biol 395(2): 232-44, Nov 2014.


Degenhardt K*, Singh M K*, Aghajanian H*, Massera D, Wang Q, Li J, Li L, Choi C, Yzaguirre A D, Francey L J, Gallant E, Krantz I D, Gruber P J, Epstein J A: Semaphorin 3d signaling defects are associated with anomalous pulmonary venous connections. Nat Med 19(6): 760-5, Jun 2013 Notes: *Co-first author with equal contribution.


Katz TC*, Singh MK*, Degenhardt K*, Rivera-Feliciano J, Johnson RL, Epstein JA, Tabin CJ: Distinct compartments of the proepicardial organ give rise to coronary vascular endothelial cells. Dev Cell 22(3): 639-650, Mar 2012 Notes: *Co-first author with equal contribution.

Gusman M, Servaes S, Feygin T, Degenhardt K, Epelman M: Multimodel imaging in the prenatal diagnosis of tuberous sclerosis complex. Case Rep Pediatr Oct 2012.


Degenhardt KR*, Milewski RC*, Padmanabhan A*, Miller M, Singh MK, Lang D, Engleka KA, Wu M, Li J, Zhou D, Antonucci N, Li L, Epstein JA: Distinct enhancers at the Pax3 locus can function redundantly to regulate neural tube and neural crest expressions. Dev Biol 339(2): 519-527, Mar 2010 Notes: Epub 2010 Jan 4.

Degenhardt K*, Wright AC*, Horng D, Padmanabhan A, Epstein JA: Rapid three-dimensional phenotyping of cardiovascular development in mouse embryos by Micro-CT with iodine staining. Circ Cardiovasc Imaging 3(3): 314-322, May 2010 Notes: Epub 2010 Feb 27.


Zhang Y, Singh MK, Degenhardt KR, Lu MM, Bennett J, Yoshida Y, Epstein JA: Tie2Cre-mediated inactivation of plexinD1 results in congenital heart, vascular and skeletal defects. Dev Biol 325(1): 82-93, Jan 2009 Notes: Epub 2008 Oct 17.


Stoller JZ, Degenhardt KR, Huang L, Zhou DD, Lu MM, Epstein JA: Cre reporter mouse expressing a nuclear localized fusion of GFP and beta-galactosidase reveals new derivatives of Pax3-expressing precursors. Genesis 46(4): 200-204, Apr 2008.


Degenhardt K, Rentschler S, Fishman G, Sassoon DA: Cellular and cis-regulation of En-2 expression in the mandibular arch. Mech Dev 111(1-2): 125-136, Feb 2002.


Degenhardt K, Sassoon DA: A role for Engrailed-2 in determination of skeletal muscle physiologic properties. Dev Biol 231(1): 175-189, Mar 2001.

Rentschler S, Vaidya DM, Tamaddon H, Degenhardt K, Sassoon D, Morley GE, Jalife J, Fishman GI: Visualization and functional characterization of the developing murine cardiac conduction system. Development 128(10): 1785-1792, May 2001.


Miller C, Degenhardt K, Sassoon DA: Fetal exposure to DES results in de-regulation of Wnt7a during uterine morphogenesis. Nat Genet 20(3): 228-230, Nov 1998.




Jay PY, Degenhardt K, Anderson, RH, Atrial Septal Defects - Molecular Pathways and Animal Models (Chapter 21) in Rickert-Sperling S, Kelly R, Driscoll D (Eds.) : Congenital Heart Diseases: The Broken Heart.  Springer 2015 Notes: ISBN 978-3-7091-1882-5.


Degenhardt K: Embryology of the Cardiovascular System (Chapter 2). Fetal Cardiovascular Imaging: A Disease Based Approach. Rychik J and Tian Z (eds.) (eds.). Elsevier, Page: 10-16, 2011 Notes: ISBN 978-1-6160-3172-7.

Posters and Presentations

Invited Lectures


Degenhardt K. "Characterization of Lung Pathology in Fetal Cardiovascular Disease"  Cardiology 2020 Annual Update on Pediatric and Congenital Cardiovascular Disease, Lake Buena Vista, FL. Feb 2020.

Degenhardt K. "Developmental Origins: How Does the Right Ventricle Form" Cardiology 2020 Annual Update on Pediatric and Congenital Cardiovascular Disease, Lake Buena Vista, FL. Feb 2020.


Degenhardt K. "Acetylation by Nat10 Protects Against Cardiac Defects in the Setting of Maternal Diabetes" Weinstein Cardiovascular Development and Regeneration Meeting, Nara, Japan. May 2018.

Awards and Honors

2014, Nominated for 2014 Preclinical Teaching Awards "Best Cardiology Course Professor in Cardiology" from The Perelman Medical School, University of Pennsylvania
2007-2009, Ruth L. Kirschstein National Research Service Award
1993, Karin Grunebaum Research Fellowship
1990, Phi Beta Kappa

Editorial and Academic Positions

Editorial Positions

2018-present, Journal of Cardiovascular Disease and Development, Editorial Board