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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

Specialties & Treatments

Treatment & Services

  • Aorta Center
  • Cardiology
  • Cardiovascular Medicine
  • Cardiovascular Medicine Department
  • Clinical Cardiology Section
  • General Cardiology
  • Perioperative Cardiac Management
View all 7 Treatment & Services +


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About Donald Hammer, MD

Dr. Donald Hammer is Director of Cardiology Surgical Services and a staff cardiologist in the Section of Clinical Cardiology, the Robert and Suzanne Tomsich Department of Cardiovascular Medicine, at the Sydell and Arnold Miller Family Heart, Vascular & Thoracic Institute. He is board certified in internal medicine and cardiology. Dr. Hammer's specialty interests are ischemic heart disease and perioperative cardiac management.

Dr. Hammer graduated summa cum laude from Case Western Reserve University (Phi Beta Kappa) with an undergraduate degree in chemistry. He received his medical degree from The Ohio State University College of Medicine, in Columbus, Ohio, where he was inducted in the Alpha Omega Alpha honor society. He completed his clinical internship and residency in internal medicine at The Ohio State University Hospitals, where he went on to receive a fellowship in cardiology.

Dr. Hammer served 10 years in the United States Naval Corps and retired as a Lieutenant Commander, U.S. Naval Medical Corps. He has had multiple academic appointments, which include Clinical Instructor in Internal Medicine at The Ohio State University Hospitals; Director of Education, Internal Medicine at the Naval Regional Medical Center at Camp Pendleton, CA; Assistant Clinical Professor of Medicine and Associate Medical Director of the Cardiac Transplantation Program at The Ohio State University Hospitals; Education Coordinator for Cardiology at Wright State University in Dayton, OH, where he was also Director of the Cardiology Fellowship Training Program; Director of the Echocardiography Laboratory and Chairman of the Cardiology Research Panel at Good Samaritan Hospital in Dayton, among others. In 1998, Dr. Hammer was appointed to the Cleveland Clinic Foundation as Director of Cardiology Surgical Services.

Dr. Hammer has long been involved in clinical studies on his specialty interests and heart related issues. His post basic research endeavors included high-energy phosphate analysis in dilated cardiomyopathy and CHF. He currently is the principal investigator on a retrospective comparison of second and third generation beta blockers and post-operative atrial fibrillation prophylaxis, and is a co-investigator on the safety and efficacy in low molecular weight heparin in selected patients post open heart surgery. Dr. Hammer has participated in many other clinical trials including the QUIET STUDY and in the GUSTO trials.

He has presented his research findings and addressed his specialty interests at many national conferences and symposia. He is the author or co-author of articles related to his work in leading publications, including Circulation, Heart, and the New England Journal of Medicine, to name a few. In addition, he has co-authored a chapter on endogenous inotrope in a medical textbook on Cardiotonic Drugs.

Dr. Hammer is Fellow in the American College of Cardiology and a member of the American Medical Association, the American Society of Echocardiography and the Medical Society of Northeastern Ohio.

Education & Professional Highlights

Education & Professional Highlights


Education & Fellowships

Fellowship - The Ohio State University Hospitals
Columbus, OH USA

Residency - The Ohio State University Hospitals
Internal Medicine
Columbus, OH USA

Internship - The Ohio State University Hospitals
Internal Medicine
Columbus, OH USA

Medical Education - The Ohio State University College of Medicine and Public Health
Columbus, OH USA

Undergraduate - Case Western Reserve University
Cleveland, OH USA


  • Internal Medicine
  • Internal Medicine - Cardiovascular Disease

Specialty Interests

General cardiology, heart disease, aorta disease, perioperative cardiac management

Research & Publications

Research & Publications

See publications for Donald Hammer, 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 5/10/2021, Dr. Hammer 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

305 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 5
Courtesy, Respect & Concern 4.9
Patient Rating of Doctor 4.9

74 Patient Comments

Reviewed on Jun 23, 2021

Very good staff and excellent Doctor and assistants!!

Reviewed on Jun 23, 2021

I will certainly recommend (I have already been doing so) this doctor and staff as the best of the best!

Reviewed on Jun 21, 2021

Dr. Hammer is a wonderful cardiologist my husband trust him and that what we love about Dr. Hammer he tells you how it is has a wonderful bed side manner . We Love You Dr. Hammer

Reviewed on Jun 21, 2021

very pleased with our doctors visit

Reviewed on May 13, 2021

Dr. Hammer has reversed a declining problem I was having with medication, But continues to monitor my progress. I think very highly of him and value his knowledge. Easy to talk to and ask questions.

Reviewed on May 13, 2021

Have recommended Cleveland Clinic and Dr. Hammer to others.

Reviewed on May 6, 2021

Dr. Hammer is the best! He always been very caring to my needs and concerns. Explains everything in detail.

Reviewed on May 6, 2021

Coming to the Cleveland Clinic, for me, is coming to the best place for all my health needs. I have been recommending Dr. Hammer and the Clinic to everyone.

Reviewed on May 3, 2021

As far as I am concerned, Dr. Hammer is one of the best doctors at the clinic.

Reviewed on Apr 29, 2021

Dr. Hammer is wonderful. He is very knowledgeable, professional, and never seems in a rush.

Reviewed on Apr 23, 2021

Donald F. Hammer MD gave me an excellent review of the results of my echocardiogram tests pointing out specific views of my heart and areas of note for my attention. His explanations were thorough and easy to understand since he simplified his communication. I have always admired how well he relates in understandable detail what is most important for my health.

Reviewed on Apr 22, 2021

Dr. Hammer was very thorough.

Reviewed on Apr 15, 2021

Dr. Hammer is awesome. I would recommend him to anyone!

Reviewed on Apr 9, 2021

I was not feeling well, so Dr Hammer was able to squeeze me in his schedule for an earlier appointment.

Reviewed on Apr 9, 2021

Dr Hammer is an incredible man and doctor. He explains things very well and truly cares about his patients.

Reviewed on Apr 9, 2021

Dr Hammer explained in detail what needs to happen to get to the bottom of my symptoms. He looked back at my previous test results and really put a lot of research and thought into the next step.

Reviewed on Apr 8, 2021

I certainly enjoyed my visit with Dr.Hammer! I felt confident with my cardiac issues after my appointment ! He does a great job !

Reviewed on Apr 8, 2021

My experience was very good ! I would recommend Dr. Hammer to anyone needing care!

Reviewed on Mar 29, 2021

very impressed with Dr Hammer and the staff

Reviewed on Mar 27, 2021

*Dr. Hammer, and his whole team, was outstanding.

Reviewed on Mar 19, 2021

Dr. Hammer is an excellent physician.

Reviewed on Mar 16, 2021

Dr Hammer gave me good direction/information that was/is very helpful in preparing me for what to expect regarding surgery/immediate post surgery and the recovery period. His information has reduced unnecessary anxiety and will help guide me thru recovery.

Reviewed on Mar 16, 2021

I can't express enough how much I appreciate Dr.Hammer's time, courtesy, concern, and care if me as a patient. He always takes time with me, answering any questions, and sharing his knowledge.

Reviewed on Mar 15, 2021

Very smooth process to get an appt with Dr. Hammer

Reviewed on Mar 15, 2021

Dr. Hammer is very good, he takes every opportunity to assure me as a patient that he is totally interested in my condition. Also, I asked Dr. Hammer that my life partner who had a recent suspected cardiac issue and I wanted him to accept her as a patient, he readily said yes and took steps to get her into his practice. Very thankful for his actions.

Reviewed on Feb 23, 2021

dr. hammers deserves to have the most effective support staff. he is the best.

Reviewed on Feb 19, 2021

providers have always been up front and courteous

Reviewed on Feb 12, 2021

Excellent communication and accessibility due to Dr.Hammer's cell phone use and responsiveness of his secretary.

Reviewed on Feb 10, 2021

Dr. Hammer is very professional, informative and understanding

Reviewed on Feb 10, 2021

I already have recommended Dr Hammer to friends.

Reviewed on Feb 2, 2021

Dr. Hammer always explains everything. He never rushes. Very thorough!

Reviewed on Feb 2, 2021

Dr. Hammer provide s an excellent experience in very way.

Reviewed on Jan 28, 2021

Dr. Hammer is extremely kind,, courteous and very polite. I am blessed to have such an attentive cardiologist.

Reviewed on Jan 28, 2021

Dr. Hammer is a great Cardiologist. He takes time and is not rushed.

Reviewed on Jan 27, 2021

Dr. Hammer is absolutely superb! One of the best doctors ever.

Reviewed on Jan 25, 2021

I have recommended to Dr. Hammer to other people I know in Sylvania, Ohio. I trust him explicitly. He takes the time to review my history and explains test results without being demeaning which I appreciate greatly. I feel that he cares about me through congruency of his words, actions, and body language.

Reviewed on Jan 25, 2021

Dr Hammer is the best in his field. wonderful experience meeting him.

Reviewed on Jan 22, 2021

I was very pleased with the entire experience and the concern that Dr. Hammer showed helping me with my concerns.

Reviewed on Jan 18, 2021

Dr. Hammer clearly cares about me as a person, and is genuinely concerned for my well-being. He is an extremely good listener who takes the time to deeply understand my struggles and concerns. Then he addresses my issues clearly and thoroughly. I live far from Cleveland in central Mexico and have no ties to Ohio. But I will keep Dr. Hammer as my Cardiologist as long as he continues practicing because of his outstanding level of care. I would strongly recommend Dr. Hammer to anyone.

Reviewed on Jan 5, 2021

A great experience from beginning to end. The professionalism at CCF stands out far beyond most other organizations. the sonographer for my echo "Jen" was very very good. Dr. Hammer and the resident he was working with were thorough and explained everything. Very fortunate to be treated at CCF.

Reviewed on Dec 18, 2020

I was treated with respect, care and nurturing from all the doctors and nurses.

Reviewed on Dec 18, 2020

Dr. Hammer is a very kind and compassionate doctor

Reviewed on Dec 17, 2020

Dr. Hammer is excellent.

Reviewed on Dec 15, 2020

excellent care provider

Reviewed on Dec 8, 2020

Dr McCurry's team did an amazing job planning my visit at the Cleveland Clinic There was little I needed to do in the area

Reviewed on Dec 3, 2020

Dr. Hammer & his assistant, Charlie, are fantastic!!

Reviewed on Nov 10, 2020

Dr.Hammer is an exceptional physician who not only displays exceptional clinical competency but also compassion and empathy.

Reviewed on Nov 10, 2020

Dr. Hammer truly manifests the professed goals of Cleveland Clinic.

Reviewed on Nov 6, 2020

doctor hammer is very compassionate regarding my concerns. took time to help me understand my concerns I grateful for is for his knowledge and compassion

Reviewed on Nov 6, 2020

Dr. Hammer is always extremely well prepared and informed, thorough and patient.

Reviewed on Nov 5, 2020

Very pleased with the care, especially Dr. Hammer, he was outstanding!

Reviewed on Oct 29, 2020

Dr. Hammer gave me all the time I needed to answer any questions i had and made sure I understood thank him and his staff for a good visit

Reviewed on Oct 7, 2020

dr hammer is an excellent care giver who always takes whatever time is necessary to understand and analyze my conditions or concerns

Reviewed on Oct 1, 2020

Dr. Hammer is the best!

Reviewed on Sep 30, 2020

My husband and I both see Dr. Hammer and we cannot say enough good things about Dr. Hammer. We have recommended Dr. Hammer to four people all of whom followed our recommendation and allfour of them love him as much as we do. Best doctor ever!!!!

Reviewed on Sep 24, 2020

The appointment was a good and informative doctor visit.

Reviewed on Sep 24, 2020

I would recommend DR HAMMER TO FRIENS AND FAMILY in fact we already have.

Reviewed on Aug 19, 2020

Have been consulting with Dr. Hammer for 12 years now. I feel blessed and fortunate to have him as my Doctor. Without question, he is first class in all aspects of his profession.

Reviewed on Aug 19, 2020

dr hammer was very informative

Reviewed on Aug 17, 2020

No bad experience Dr. Hammer has been my doctor for 12 yrs. Thank you Dr. Hammer for choosing cardiologist as your profession.

Reviewed on Aug 17, 2020

My 3 Cardiology appointments were scheduled by Dr Hammers office. They assumed they were doing me a favor to make all three on the same day... As I live 5 minutes drive from the clinic, two separate days would have been far better!By the time I saw Dr Hammer st the end ofthe day, he apologized for being over an hour late. I was ok with that, until he reported having just spent 90 min. with each of two new patients. (The appointments are scheduled for 30 - 40 min.) I realized Dr Hammer was on hisway to a departmental meeting, as he hastilydescribed my own aortic stenosis & scribbled some drawings.I am also a first time patient. Perhaps my appointment should have been rescheduled? I have a PhD in Medieval History- no preparation for a rapid fire run through of gradients , et alia.I am believing this is a confidential response!If not, I will be off to UH, where my seconddaughter is an Attending physician in Critical care ( There was no response requested for the Echocardiogram... Ten days later, I stillhave bruises on and below my left breast.)Final point: YOU MUST notify patients that only one door is open at the fountain. As I parked at Carnegie/ E. 100th, I ended up jogging 3/4 mile to avoid being late for the first appointment. Dr Hammer later joked that would "do" as a stand in for stress test.

Reviewed on Aug 12, 2020

we Love Dr Hammer!!!

Reviewed on Aug 11, 2020

Dr. Hammer always takes time to answer any questions or concerns. He really seems to care about his patients health and well being.

Reviewed on Aug 11, 2020

Dr Hammer provided excellent care.

Reviewed on Aug 10, 2020

I like this method as it places great focus on the discussion between the doctor and patient

Reviewed on Aug 10, 2020

very professional service. I am very happy to have Dr. Hammer and his staff providing my cardiac care.

Reviewed on Aug 6, 2020

Dr. Hammer and his staff are always very attentive. Neither the assistant,nor Dr. Hammer ever make me feel like I am being rushed through. Dr. Hammer always takes whatever time necessary to be sure all my questions are answered and I understand test results.

Reviewed on Aug 4, 2020

Excellent. Dr. Hammer is so good to us. Great doctor for my mother.

Reviewed on Aug 4, 2020

Nothing will ever replace seeing Dr. Hammer in person. But this was 2nd best.

Reviewed on Aug 3, 2020

Doctor Hammer was very honest and I felt like I was his only patient. he is very professional. thank you.

Reviewed on Jul 30, 2020

Dr. Hammer is always supportive, concerned, informative, and patient. It's clear that he cares about his patients and he explains things well.

Reviewed on Jul 29, 2020

After my initial contact with Dr. Rosellis office by phone, communications between myself and the Cleveland Clinic, requests for my medical records and tests which I promptly provided, and subsequent scheduling of appointments and tests at the Clinic went very well.

Reviewed on Jul 29, 2020

My morning appointment with a Resident cardiologist, and then with Dr. Hammer (prior to the CT scan and Echocardiogram tests I had) went well. The Resident cardiologist, looking at my CT scan from January at Union Hospital, and echocardiogram performed at Aultman Hospital in February, measured my aneurysm at 4.8 to 4.9. This was larger than the 4.5 to 4.6 diameter as measured by Dr. D'Agostino at Aultman, from the same tests. I didn't get a very good explanation of the different aneurysm size measurements by Aultman and Cleveland Clinic physicians from the same tests. My visit with Dr. Rosellis was very short, as he was called to surgery after only 5-6 minutes with me. I didn't get to ask him a single question regarding my aneurysm condition, limits to physical activity, details of surgery to repair the aneurysm, how long would be in the hospital following surgery, how long to recover, and so on. This is in no way a criticism of Dr. Roselli - if and when I need to have my aneurysm surgically repaired, I would certainly want Dr. Roselli and his surgical team to perform the operation. I am just expressing my disappointment in the brevity of my consultation with him. I fully understand that he was unexpectedly called away in urgency.

Reviewed on Jul 15, 2020

I deeply appreciate Dr. Hammer's concern for me and my well-being.

Related Videos Featuring Donald Hammer, MD

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