About Jag Singh, MD, PhD

Jag Singh, MD, DPhil is a Professor of Medicine at Harvard Medical School. He served as the Clinical Director of the Cardiology Division and the Roman W. DeSanctis Endowed Chair in Cardiology from 2015-2020. He is also the Founding Director of the Resynchronization and Advanced Cardiac Therapeutics Program, at the Massachusetts General Hospital Heart Center. Dr. Singh received his medical degree from BJ Medical College, Pune University, India. He completed his internal medicine residency, cardiology and cardiac electrophysiology fellowships at Mass General. He also earned a doctorate from Oxford University, a master of science in clinical investigation from MIT-Harvard and a research fellowship at the Framingham Heart Study.

Dr. Singh's research interests are in clinical cardiac electrophysiology. Dr. Singh is the national & global principal investigator on 5 ongoing multi-center clinical trials in device therapy for heart failure and catheter ablation for atrial fibrillation. He is also a member of several steering committees for multicenter research studies. Much of his other efforts are focused on the delivery of cardiovascular care while adapting to health care reform, population health initiatives and furthering the digital footprint of the Heart Center. Dr. Singh is on the editorial board of several medical journals, Deputy Editor of the Journal of American College of Cardiology: Clinical EP and editor-in-chief of the Current Treatment Options in Cardiovascular Medicine. Dr. Singh is an internationally recognized speaker and frequently gives lectures at national/ international educational forums. Dr. Singh has over 300 publications inclusive of original research articles, text book chapters, review articles and editorials. He has edited a Textbook on Imaging in Electrophysiology.

Clinical Interests:




Mass General Heart Center
55 Fruit St.
Boston, MA 02114
Phone: 866-644-8910

Mass General: Demoulas Center for Cardiac Arrhythmias
55 Fruit St.
Boston, MA 02114
Phone: 617-724-4500

Medical Education

  • MBBS, University of Poona, B.J. Medical College, India
  • Residency, David Sassoon General Hospital,Poona, India
  • Residency, King Edward Memorial Hospital, Bombay, India
  • Residency, Massachusetts General Hospital
  • Fellowship, Framingham Heart Study, BU School of Medicine
  • Fellowship, John Radcliffe Hospital

American Board Certifications

  • Cardiovascular Disease, American Board of Internal Medicine
  • Clinical Cardiac Electrophysiology, American Board of Internal Medicine

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  • Risk stratification for sudden cardiac death and worsening heart failure. Dr. Singh has done extensive work with the Framingham Heart Study and the MADIT Study group and published several landmark manuscripts.
  • Patient selection and predicting response to cardiac resynchronization therapy. Dr. Singh has developed and built a new multidisciplinary program at Massachusetts General Hospital to care for patients with heart failure and implanted devices. His research work has led to the development of a novel response score to predict clinical outcome in this patient group.
  • Coronary venous anatomy and novel ventricular lead implantation strategies. Dr. Singh has used novel rotational venography and imaging techniques to propose and substantiate new coronary venous anatomy classification and redefine the best views for lead implantation. Dr. Singh published on the importance of left ventricular lead position and developed new implantation protocols, some of which are being tested prospectively in clinical studies.
  • Image integration strategies and multimodality imaging for cardiac resynchronization therapy. Dr. Singh has done some novel work integrating computed tomography, ultrasound and fluoroscopy to create better clinical strategies to facilitate device implantation.
  • Device diagnostics and remote monitoring in heart failure patients. Dr. Singh's recent work has focused on the use of remote monitoring and device diagnostics to prognosticate and manage patients.
  • Newer drugs and catheter ablation strategies of atrial fibrillation. Dr. Singh is actively engaged in research examining newer drug therapies for atrial fibrillation. His research interests also examine novel approaches to enhance patient selection, imaging and ablative techniques for treating atrial fibrillation.


  • Select Publications:

    • Singh JP et al. Abnormal rate adaptation of the QT interval is associated with hypertensive left ventricular hypertrophy. J Am Coll Cardiol 1997;29:778.
    • Singh JP et al. Heritability of heart rate variability: the Framingham Heart Study. Circulation, 1999;99: 2251.
    • Singh JP et al. Factors influencing appropriate firing of the implanted defibrillator for ventricular tachycardia/fibrillation: findings from MADIT II. J Am Coll Cardiol 2005 46:1712.
    • Singh JP et al. Coronary venous anatomy: a segmental approach to aid cardiac resynchronisation therapy. J Am Coll Cardiol . 2005;46:68.
    • Heist EK et al, Singh JP. Usefulness of a Novel Response Score to Predict Hemodynamic and Clinical Outcome from Cardiac Resynchronization Therapy. Am J Cardiol. 2006;97:1732-6.
    • Singh JP, et al. Left ventricular lead electrical delay predicts response to cardiac resynchronization therapy Heart Rhythm. 2006;3:1285.
    • Tournoux F et al, Singh JP. Echocardiographic Measures of Acute Hemodynamic Response after Cardiac Resynchronization Therapy Predict Long-term Clinical Outcome. European Heart Journal, 2007;28:1143.
    • Singh JP. Electrical Therapy for Advanced Heart Failure: Is it Time for a Multidisciplinary Approach or a New Subspecialty? Expert Rev Cardiovasc Ther. 2007;5:811.
    • Singh JP et al. Patient selection and classification for atrial fibrillation ablation: Thinking beyond duration. 2009;6:1522.
    • Upadhyay G et al, Singh JP. Cardiac Resynchronization in Patients with Atrial Fibrillation: a Meta-analysis of Prospective Cohort Studies. J Am Coll Cardiol 2008;52:1239.

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