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Department Cardiovascular Medicine
Primary Location Cleveland Clinic Main Campus
Type of Doctor Adults Only
Languages English
Surgeon No
Cleveland Clinic Main Campus
Primary Location

Cleveland Clinic Main Campus


Additional Locations

Specialties & Treatments

Treatment & Services

  • Advanced Ischemic Heart Disease Center
  • Atrial Fibrillation Center
  • Biventricular Pacemaker
  • Cardiac Electrophysiology
  • Cardiac Electrophysiology & Pacing Section
  • Cardiovascular Medicine
  • Cardiovascular Medicine Department
  • Cardioversion
  • Catheter Ablation
  • Clinical Trials
  • Implantable Cardioverter Defibrillator
  • Lead Extraction (ICD, Pacemaker)
  • Lifevest
  • Pacemaker Implant
  • Pulmonary Vein Ablation Procedure
View all 15 Treatment & Services +

Specialty in Diseases & Conditions

  • Abnormal Heart Beats - Women
  • Abnormal Heart Rhythms
  • Arrhythmogenic Right Ventricular Dysplasia
  • Atrial Fibrillation
  • Atrial Flutter
  • Bradyarrhythmias
  • Cardiac Implantable Electronic Device Infection
  • Heart Palpitations
  • Long QT Syndrome (LQTS)
  • Sudden Cardiac Death (Sudden Cardiac Arrest)
  • Supraventricular Tachycardia
  • Syncope
  • Ventricular Fibrillation
  • Ventricular Tachycardia
  • Wolff-Parkinson-White Syndrome (WPW)
View all 15 Specialties +


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About Thomas Callahan, MD

Thomas Callahan, IV, MD, is Staff Physician and Director of Inpatient Services in the Section of Pacing and Electrophysiology of the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute at Cleveland Clinic. He is also the Associate Program Director for Cleveland Clinic’s cardiology and electrophysiology fellowships.

In addition to office visits, Dr. Callahan also offers scheduled follow up virtual visits to select patients, through the Cleveland Clinic Express Care ® Online app. This platform allows patients to see their physician live, using their smartphone, tablet or computer.

Specialty interests: Abnormal heart rhythm, atrial fibrillation, sudden cardiac death, supraventricular tachycardia, ventricular tachycardia, PVCs, Wolff-Parkinson-White syndrome, biventricular pacemaker, catheter ablation, implantable cardiac defibrillator, lead extraction

Number of Procedures Performed: Dr. Callahan has performed more than 900 catheter ablation procedures throughout his career.

Success rates: Cleveland Clinic has been ranked the #1 hospital for cardiology and heart surgery by U.S. News & World Report since 1994. Success rates for specific procedures are available at

Education and Training: Dr. Callahan received his undergraduate degree from Oberlin College, OH. He received his master's degree from the University of Michigan, and he earned his medical degree from Eastern Virginia Medical School, Norfolk. He joined Cleveland Clinic in 2003 and completed fellowships in Cardiovascular Medicine Cardiac Electrophysiology and Pacing. Prior to coming to Cleveland Clinic, he was a resident at the Hospital of the University of Pennsylvania, where he was Chief Resident in internal medicine.

Publications and Speaking:  Dr. Callahan has authored and co-authored many articles published in leading medical journals.

About Dr. Callahan: “I enjoy my field because we have the ability to make many patients feel dramatically better. I am also excited by the constant advancement in the field.”

Leisure Activities: Dr. Callahan is a private pilot. He also enjoys skiing and spending time with his family.

Education & Professional Highlights

Education & Professional Highlights


Education & Fellowships

Fellowship - Cleveland Clinic
Cardiovascular Medicine
Cleveland, OH USA

Residency - Hospital of the University of Pennsylvania
Internal Medicine
Philadelphia, PA USA

Internship - Hospital of The University of Pennsylvania
Internal Medicine
Philadelphia, PA USA

Medical Education - Eastern Virginia Medical School
Norfolk, VA USA

Graduate School - University of Michigan
Ann Arbor, MI USA

Undergraduate - Oberlin College
Oberlin, OH USA


  • Internal Medicine - Cardiovascular Disease
  • Internal Medicine - Clinical Cardiac Electrophysiology
  • Internal Medicine - Cardiovascular Disease

Specialty Interests

Abnormal heart rhythm, atrial fibrillation, sudden cardiac death, supraventricular tachycardia, ventricular tachycardia, PVCs, Wolff-Parkinson-White syndrome, biventricular pacemaker, catheter ablation, implantable cardiac defibrillator, lead extraction

Awards & Honors

  • 2006, Dawson Award for Clinical Excellence and Humanism
  • 2004, Frederic J. Pashkow Award for Clinical Excellence
Research & Publications

Research & Publications

See publications for Thomas Callahan, MD.

(Disclaimer: This search is powered by PubMed, a service of the U.S. National Library of Medicine. PubMed is a third-party website with no affiliation with Cleveland Clinic.)

Industry Relationships

Industry Relationships

Cleveland Clinic physicians and scientists may collaborate with the pharmaceutical or medical device industries to help develop medical breakthroughs or provide medical expertise or education. Cleveland Clinic strives to make scientific advances that will benefit patient care and support outside relationships that promise public benefit. In order for the discoveries of Cleveland Clinic physicians' and scientists' laboratories and investigations to benefit the public, these discoveries must be commercialized in partnership with industry. As experts in their fields, Cleveland Clinic physicians and scientists are often sought after by industry to consult, provide expertise and education.

To assure professional and commercial integrity in such matters, Cleveland Clinic maintains a program that reviews these collaborations and, when appropriate, puts measures in place to minimize bias that may result from ties to industry. Cleveland Clinic publicly discloses the names of companies when (i) its physicians/scientists receive $5,000 or more per year (or, in rare cases, equity or stock options) for speaking and consulting, (ii) its physicians/scientists serve as a fiduciary, (iii) its physicians/scientists receive or have the right to receive royalties or (iv) its physicians/ scientists hold any equity interest for the physician's/scientist's role as inventor, discoverer, developer, founder or consultant.* In publicly disclosing this information, Cleveland Clinic tries to provide information as accurately as possible about its physicians' and scientists' connections with industry.

As of 2/20/2023, Dr. Callahan has reported no financial relationship with industry that is applicable to this listing. In general, patients should feel free to contact their doctor about any of the relationships and how the relationships are overseen by Cleveland Clinic. To learn more about Cleveland Clinic's policies on collaborations with industry and innovation management, go to our Integrity in Innovation page.

Public Health Service-Reportable Financial Conflicts of Interest. Cleveland Clinic scientists and physicians engage in basic, translational and clinical research activities, working to solve health problems, enhance patient care and improve quality of life for patients. Interactions with industry are essential to bringing the researchers' discoveries to the public, but can present the potential for conflicts of interest related to their research activities. Click here to view a listing of instances where Cleveland Clinic has identified a Public Health Service (PHS)-Reportable Financial Conflict of Interest and has put measures in place to ensure that, to the extent possible, the design, conduct and reporting of the research is free from bias.

* Cleveland Clinic physicians and scientists subscribe to the guidance presented in the PhRMA Code on Interactions with Healthcare Professionals and the AdvaMed Code of Ethics on Interactions with Health Care Professionals. As such, gifts of substantial value are generally prohibited.

Patient Satisfaction Reviews

225 Patient Satisfaction Reviews

The Patient Satisfaction Rating is an average of all responses to the care provider related questions shown below from our nationally-recognized Press Ganey Patient Satisfaction Survey. Patients that are treated in outpatient or hospital environments may receive different surveys, and the volume of responses will vary by question.

Responses are measured on a scale of 1 to 5 with 5 being the best score.

The comments are submitted by patients and reflect their views and opinions. The comments are not endorsed by and do not necessarily reflect the views of Cleveland Clinic.

Overall Star Ratings
4.9 out of 5
Explains 4.9
Listens 4.9
Courtesy, Respect & Concern 4.9
Patient Rating of Doctor 4.9

37 Patient Comments

Reviewed on Feb 3, 2023

He was very approachable and was well abreast of my medical history especially since I was his new patient (2 visits only).. He listened to my concerns and answered my questions. He also spent time with me during my visit when many doctors barely give you 20 minutes of their time. I think that I will really like being his patient.

Reviewed on Feb 3, 2023

Doctor and his staff were top rate

Reviewed on Jan 13, 2023

Excellent medical staff. I'm very happy with doctor

Reviewed on Dec 30, 2022

Dr. Callahan was excellent. He took significant time to listen to the details of the episode and history. He spent a significant amount of time explaining the condition, likelihood of recurrence, risk stratification scoring system that contributed to decision making, and the various approaches available. We went over home monitoring devices. He included my input in decisions regarding approach to care. He made sure that my understanding was good and that all of my questions were answered, and he provided educational literature to take home as well as his phone number as needed for future questions and concerns. It was a wonderful example of patient engagement and personalized care.

Reviewed on Dec 27, 2022

Excellent service from Cleve Clinic and Dr. Callahan .

Reviewed on Dec 27, 2022

Dr callahan is the best

Reviewed on Dec 23, 2022

Dr.researched my problem and reassured me of his thoroughness. A very valuable asset to the Cleveland Clinic staff.

Reviewed on Dec 21, 2022

This experience with this provider was great-in general, contacting a provider is usually very difficult unless you have his direct number

Reviewed on Dec 21, 2022

Provider offered a thorough discussion of my problem and options to solve the issue - answered all questions in detail and made an effort to schedule an immediate procedure

Reviewed on Dec 9, 2022

The doctor took a long time to describe my condition in plain language and what treatment options were available.

Reviewed on Nov 29, 2022

Dr Callahan and is entire staff was very knowledgeable, informative and helpful in my family's meeting with them.

Reviewed on Nov 25, 2022

Dr. Callahan is terrific!

Reviewed on Nov 25, 2022

I was very pleased with Dr Callahan I believe he will help I was a surgical nurse for years and just can tell

Reviewed on Nov 18, 2022

Very organized and prompt service. Dr. Callahan explained everything and was very professional! Loved his socks!

Reviewed on Nov 15, 2022

My meeting experience with Dr.Callahan was fantastic. The interview went smoothly Dr. Callahan made my wife and I feel very comfortable and relaxed. We never felt rushed and had an excellent conversation about my issues. Dr.Callahan explained everything to us and answered all our questions in great detail in a way that we could understand. Could not ask for a better session. Some of the news was not that great but he did put us at ease with his delivery and explanation in detail.

Reviewed on Oct 28, 2022

Wonderful dr and place to go too

Reviewed on Oct 28, 2022

Love dr Callahan

Reviewed on Sep 30, 2022

I appreciated meeting with a knowledgeable doctor who was extremely focused on the question of the appropriate procedure for my medical problem

Reviewed on Sep 14, 2022

Dr Callahan and his Staff are truly excellent

Reviewed on Sep 9, 2022

Dr was very professional and very knowledgeable

Reviewed on Aug 31, 2022

My experience with Dr. Callahan is always very good. And he is a very good listener and gives sound advice. He is my physician since 2016 and I appreciate all his help.

Reviewed on Aug 23, 2022

Dr. Callahan listened closely and spent a fair amount of time during my appt

Reviewed on Aug 23, 2022

Dr Callahan was very thorough, knowledgeable and helpful

Reviewed on Aug 12, 2022

Dr T. Callahan did an excellent job in talking to me about my condition and I did not feel rushed. Concerning the overall assessment, the wait time for a test before seeing the doctor, I felt was somewhat excessive. Regarding getting care, I think that being switched around to different people on the "call tree" took more time than necessary.

Reviewed on Jul 29, 2022

Dr. Callahan was very thorough explaining everything to me and took the time to answer all my questions. He listened to all my concerns, and addressed each one. I have complete confidence in him.

Reviewed on Jul 22, 2022

No problem with doctor at all. Wait time was very long with no explanation from anyone.

Reviewed on Jul 8, 2022

Dr Callahan listened to my concerns and provided options.

Reviewed on Jun 14, 2022

Very satisfied, as usual, with Dr. Callahan.

Reviewed on Jun 10, 2022

This part of my visit was excellent. Dr. Callahan and the nurse were very nice. Dr. Callahan went over my test results and explained them to me. Everything was good.

Reviewed on May 4, 2022

Again, my.Again, my experience was outstanding. Dr. Callahan helped me decide on a PVI ablation and my follow up course of treatment. It was a real two way discussion.

Reviewed on May 3, 2022

Dr Callahan is a very compassionate dr, listens well.

Reviewed on Apr 29, 2022

Dr. Callahan was amazing! He went above and beyond in every way! I would highly recommend him to anyone needing to be seen for cardiology

Reviewed on Apr 14, 2022

The care provided by the physicians/doctors was outstanding.

Reviewed on Apr 11, 2022

*Dr. Bhat, *Dr. Courson & NP *Jessica Lebecray were wonderful and I'm grateful for the care they gave me.. Thank you!

Reviewed on Apr 8, 2022

Dealing with Dr Callahan and his support group couldn't be better

Reviewed on Apr 5, 2022

Great visit with Dr Callahan

Reviewed on Apr 5, 2022

Dr. Callahan is the BEST. He is caring, kind, and extremely helpful, I know, I can't have a better DOCTOR. Thank goodness, I made the decision many years ago to entrust my care to the Cleveland Clinic.

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