James Daniels, M.D., is an Associate Professor in the Department of Internal Medicine at UT Southwestern Medical Center, and a member of the Division of Cardiology. A specialist in cardiac arrhythmias, he also leads UT Southwestern’s Pacemaker and Defibrillator Clinic.

Originally from New Jersey, he holds bachelor's degrees in cell biology and chemistry, both earned with distinction and honors from the University of Kansas in Lawrence. He received his medical degree from UT Southwestern and completed internal medicine residency training at the University of New Mexico Health Sciences Center in Albuquerque, where he served as Chief Resident. He then obtained advanced training through fellowship programs in cardiovascular diseases and cardiac electrophysiology at UT Southwestern.

Certified by the American Board of Internal Medicine in cardiovascular disease and clinical cardiac electrophysiology, Dr. Daniels joined the UT Southwestern faculty in 2009.

In addition to his patient care responsibilities, Dr. Daniels frequently lectures to UT Southwestern’s cardiology, electrophysiology, and internal medicine trainees. His current research interests include MRI-compatible implantable cardiac devices and atrial fibrillation.

Dr. Daniels has published a number of peer-reviewed articles and delivered several invited lectures related to cardiac arrhythmias. He serves as an ad hoc reviewer for publications that include the Journal of Cardiovascular ElectrophysiologyJournal of Investigative Medicine, and American Journal of Cardiology.

Dr. Daniels is an active member of several professional organizations, including the American Heart Association, American College of Cardiology, Heart Rhythm Society, and the American Medical Association.

Dr. Daniels was included in D Magazine's Best Doctors list for 2022, 2021, 2020, and 2018.

Personal Note

Dr. Daniels and his wife, a dermatologist, have three children.


Medical School
UT Southwestern Medical School (2001)
University of New Mexico Health Science Center (2004), Internal Medicine
University of New Mexico Health Science Center (2005), Internal Medicine
UT Southwestern Medical Center (2008), Cardiovascular Disease
UT Southwestern Medical Center (2009), Cardiac Electrophysiology

Research Interest

  • Aldosterone antagonism to reduce myocardial fibrosis and arrhythmogenesis
  • Cosmetic pacemaker and defibrillator implantation
  • Reduction of procedural fluoroscopy (X-ray) exposure


Featured Publications LegendFeatured Publications

Honors & Awards

  • Fellow
    American College of Cardiology (2009)
  • Fellow
    Heart Rhythm Society (2009)
  • Certificate of Recognition
    University of New Mexico Hospital (2005)

Professional Associations/Affiliations

  • American College of Cardiology (2009)
  • American Heart Association (2009)
  • American Medical Association (2009)
  • Heart Rhythm Society (2009)