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Gregory S. Thomas M.D.

Gregory S. Thomas M.D.

(949) 364-3388
Primary Specialties
  • Cardiovascular Disease
  • Cardiology
  • Languages Spoken
    Primary Office
    26800 Crown Valley Pkwy #120
    Mission Viejo, CA 92691
    (949) 364-5026
    Monday :2 pm :6 pm.
    Tuesday :2 pm :6 pm.
    Wednsday :2 pm :6 pm.
    Friday :2 pm :6 pm.

    Web Page:

    Experience & Education

    Other Specialties/Certifications
    American Board of Internal Medicine

    American Board of Internal Medicine
    Medical School:
    University of California, San Francisco

    Massachusetts General Hospital

    Massachusetts General Hospital

    Massachusetts General Hospital 1986
    Cedars-Sinai Med Ctr - GME 1984

    Other Educations:
    MPH, UC Berkeley
    Areas of Expertise
    Nuclear Cardiology (stress testing), Preventive Cardiology, Research and Teaching

    Physician Bio

    Dr. Thomas serves as an MIMG clinical and research cardiologist. He directs the Nuclear Cardiology program and serves as co-director of CT Services and the Lipid Clinic. In addition, he teaches at the University of California, Irvine School of Medicine where he is a Clinical Professor of Medicine and Director of Nuclear Cardiology Education. He is a Past President of the American Society of Nuclear Cardiology (ASNC) and serves on an array of committees within ASNC and the American College of Cardiology.

    He has had a long interest in research, serving as the national or local Principal Investigator or Co-Principal Investigator of 45 clinical trials. His primary areas of research are in nuclear, preventive and clinical cardiology. He serves, and has served, as a consultant to a number of companies developing new molecules for clinical use. His research work is reflected in over 100 articles, abstracts, book chapters and the text Exercise & Health: The Evidence and the Implications. He frequently presents his work in the US and abroad.

    His major contributions in nuclear cardiology have been helping pioneer the addition of low level exercise to adenosine stress, databasing and prognostic studies of outpatient myocardial perfusion imaging, encouraging the merging of nuclear cardiology images with those of cardiac CT and developing protocols for the use of a new stress vasodilator agent, regadenoson, with low level exercise and in COPD patients.

    Beginning in 2008, he has co-led a joint US-Egyptian team that discovered that ancient Egyptian mummies housed at the National Museum of Antiquities in Cairo, Egypt had atherosclerosis. This work challenges the conventional wisdom that atherosclerosis is a disease of contemporary humans. These findings were reported in the Journal of the American Medical Association and globally both on television and the print media including features in the New York Times, the Wall Street Journal and Al-Ahram. In April of 2010, on behalf of the team’s work, he received the prestigious Award of the 1st International Scientific Conference on Ancient Egyptian Culture awarded by the Egyptian Supreme Council of Antiquities and Cairo University.

    Dr. Thomas received his undergraduate degree from the University of California, Irvine, where he was a Regents Scholar, graduating Phi Beta Kappa and being named one of two Outstanding Seniors at the university. He earned his medical degree from the University of California, San Francisco where he was also a Regent’s Scholar and received Alpha Omega Alpha honors and the Chancellor’s Public Service Award upon graduation. Concomitant with medical school he studied at the University of California, Berkeley where he received a Masters of Public Health. Postgraduate training included an Internship and Residency in Internal Medicine at the Massachusetts General Hospital and Harvard Medical School and fellowships in cardiology at Cedars Sinai Medical Center in Los Angeles and the Massachusetts General Hospital.

    He serves on the Editorial Boards of the Journal of Nuclear Cardiology and JACC-Imaging, the American Heart Hospital Journal and the Tehran Heart Journal.

    In recognition of his educational contributions to the University of California, Irvine, the graduating cardiology fellows honored him with a Faculty of the Year Award in 2007.

    Areas of Interest

    Cardiovascular Disease

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