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
  • Cardiovascular Medicine Department
  • Clinical Cardiology Section
  • Perioperative Cardiac Management
View all 4 Treatment & Services +


Is Cleveland Clinic Part of Your Insurance?

Review a list of accepted insurance plans for our Northeast Ohio locations or learn more about purchasing a contracted managed care plan.

View All Plans

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 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 5/24/2018, 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

284 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 4.6
Courtesy, Respect & Concern 4.9
Patient Rating of Doctor 4.9

68 Patient Comments

Reviewed on Feb 27, 2020

Had to wait about a Month but Dr Hammand is worth the wait.

Reviewed on Feb 26, 2020

I did a lot of research before selecting Dr Hammer, and I have not been disappointed in my choice. Very competent and very caring

Reviewed on Feb 21, 2020

Wow! My family has great respect for Dr. Hammer. He is a physician who truly cares about helping. He takes time to explain thoroughly his feelings of what is happening and also what the best Treatment. I appreciated that he made my care and treatment his priority. Dr. Hammer even used his out of office time to share his findings with me. Thank you, Dr. Hammer. You are the best!

Reviewed on Feb 19, 2020

Dr. Hammer was very professional and thorough in his consultation and analysis of my health condition. He instilled confidence, knowledge and experience as he advised on and diagnosed my condition.

Reviewed on Feb 11, 2020

Very pleased with the care and time given at Cleveland Clinic. Top notch provider and staff. Will recommend him to anyone in need.

Reviewed on Feb 4, 2020

I have worked with Dr. Hammer for about 25 years. He is very competent. . like a. friend.

Reviewed on Jan 29, 2020

Dr. Hammer is a very caring DR. Specifically followed up regarding treatment and medications

Reviewed on Jan 27, 2020

Dr. Donald Hammer is always very thorough with his examination of me. He always explains everything in detail and should I have any questions, he answers them without hesitation. For this, I am very appreciative. When I leave his office, I am completely happy because any questions I may have had, have been answered.

Reviewed on Jan 15, 2020

Very pleased with all doctors and their teams.

Reviewed on Dec 20, 2019

Dr Hammer does a great job. He is an excellent doctor.

Reviewed on Dec 20, 2019

Dr. Hammer was very thorough in his assessment. I appreciated his expertise and concern for my problems.

Reviewed on Dec 13, 2019

dr. Hammer is the best he is great I love doctor hammer he goes over everything with you in detail and explains it to you so you understand

Reviewed on Dec 13, 2019

like I said before the doctor Hammer is the best he is great

Reviewed on Dec 12, 2019

I got the impression Dr. Hammer was having a bad day and not on top of his game. He seemed a bit distracted going off in many directions about healthcare in general and not focused entirely on his patient. I asked for my cardiac rehab script, and he asked me to go get a chest x-ray and that he would order the script. Upon my return Charlie was unavailable and I waited another ten minutes and then left.

Reviewed on Dec 11, 2019

I had a great experience . I'm very happy with Dr. Hammer.

Reviewed on Dec 5, 2019

Dr. Donald Hammer is a. very professional doctor at the Clinic. He is knowledgeable about my issues and explains them to me so I can understand them. Cleveland Clinic is very fortunate to be him on staff.

Reviewed on Nov 22, 2019

excellent physician goes the extra mile

Reviewed on Nov 22, 2019

Dr. Hammer is phenomenal!

Reviewed on Nov 21, 2019

Have always had the best care with Dr Hammer.

Reviewed on Nov 20, 2019

dr Hammer is great

Reviewed on Nov 14, 2019

As always, I was very impressed with Dr. Hammer.

Reviewed on Nov 14, 2019

Dr. Hammer was very caring,informative and timely. He took his Time in explaining my problem in addiction . I did not feel rushed nor did I feel intimidated to ask a question.

Reviewed on Nov 14, 2019

I did not have any bad experiences at the Cleven clinic . All personell were , caring and cordial. All doctors and nurses made you feel that your health needs were going to be met and they truly cared about the outcome . The facility was extremely clean.

Reviewed on Nov 11, 2019

Dr. Hammer is great!!!

Reviewed on Oct 17, 2019

Dr. Hammer is just awesome takes time with me and is very knowledgeable. I wouldn't go anywhere else . Dr. Hammer has such a good bed side manner he is perfect. He saved my life.

Reviewed on Oct 17, 2019

Dr. Hammer so knowledgeable and has awesome bedside manner . we all love Dr. Hammer.

Reviewed on Oct 16, 2019

dr. Hammer and his staff worked hard to get all of my appointments scheduled while I was here from Northh Carolina.

Reviewed on Sep 25, 2019

this was a regular follow up appointment for my aortic valve stenosis. a student accompanyed Dr. Hammer which did not negatively affect the quality of the visit in any way.

Reviewed on Sep 25, 2019

love Dr Hammer

Reviewed on Sep 19, 2019

wonderful physician!!

Reviewed on Sep 12, 2019

superb provider

Reviewed on Sep 10, 2019

love Dr. Hammer

Reviewed on Sep 10, 2019

I did a lot of research in selecting Dr Hammer and I was very satisfied with my initial visit. He spent 45 mins with me reviewing my medical history and asking me a lot of questions. I am confident I made a good decision to have Dr Hammer as my cardiologist.

Reviewed on Sep 9, 2019

The entire staff and fellow were excellent.I will wait as long as necessary for Dr. Hammer as he is exceptional. Scheduling tends to over schedule him. but with his work ethic he takes the time necessary and beyond making certain the patient understands.

Reviewed on Sep 9, 2019

experience very good, DR Hammer is always responsive to questions and so very courteous and dear....

Reviewed on Aug 30, 2019

Dr Hammer is an amazing Dr. He has been keeping up with everything as he tries to come up with my final diagnosis and treatment plan.

Reviewed on Aug 22, 2019

Dr. Hammer is a very caring and thorough individual. He explains all procedures and strategy thoroughly - sometimes too thoroughly, a lay person sometimes becomes lost in a complicated explanation..

Reviewed on Aug 21, 2019

Dr. Hammer is outstanding.

Reviewed on Aug 20, 2019

Really liked Dr. Hammer. He spent more time with me in one appt than my local cardiologists have in total over the past several years. Answered all my questions and provided some very insightful input re my condition and upcoming surgery.

Reviewed on Aug 19, 2019

My visits with Dr. Hammer are always professional and caring.

Reviewed on Aug 5, 2019

Always a pleasure and reassuring having a visit and exam with Dr. Hammer.

Reviewed on Jul 12, 2019

thank you Dr. Hammer for you care, detailed explanation of my cardiac issues, and future procedures. Dr. Hammer, I am so grateful to have come under your care.

Reviewed on Jul 10, 2019

*Dr. Hammer and his entire staff spent a great deal of time with me and I received tremendous care!

Reviewed on Jul 8, 2019

Dr. Hammer always spends as much time as needed with his patients therefore if we wait to see him we know that he is giving prior patients the time they need. We do not mind if we wait,

Reviewed on Jul 8, 2019

dr hammer was very polite and informative. he made me feel like i was his only patient. he did not rush me and listened to everything i had to say

Reviewed on Jul 2, 2019

dr Hammer is a very approachable person.very good at listening

Reviewed on Jul 1, 2019

Dr Hammer is very good at explaining my heart condition, long term prognosis and options.

Reviewed on Jun 26, 2019

Dr. Hammer was determined to find the cause of my heart trouble. In no time at all he had my blod pressure under control and my heart pumping better. i found him to be a kind and compassionate doctor.

Reviewed on Jun 26, 2019

I wish all the doctors I deal with and have dealt with could be like doctor Hammer but I know that is impossible. He actually makes me feel like he is concerned and cares about me and my well being.

Reviewed on Jun 19, 2019

great doctor

Reviewed on Jun 14, 2019

Dr. Hammer is a joy to meet with. He's also very pleasant, informative, knowledgeable, and genuinely concerned. Plus, he really takes the time to get to know you. At the morning of our day at the Clinic, we spent some time in the bookstore at main campus. Dr. Hammer was there, and he saw us before we saw him, and he walked over to us, said hello and talked briefly, and knew what time our appointment with him was in the afternoon. He truly cares for his patients.

Reviewed on Jun 3, 2019

Even though all of the above were "Very Good", the appointment went badly when Dr. Hammer found out that the tests he had wanted done were not even scheduled. Fortunately we were staying at a friends house in Cleveland and I was able to come back the following day and avoid a two hour drive to get the test he wanted done. Furthermore, I really enjoy and appreciate Dr. Hammer's demeanor and personality, and he followed up on the botched visit in a very professional way. Dr. Hammer is "A-#1" in my book. rrc

Reviewed on May 30, 2019

Dr. Hammer is the best. He literally saved my life. I couldn't be happier with a Doctor.

Reviewed on May 30, 2019

I always speak highly of my care from Dr. Hammer and the Cleveland Clinic.

Reviewed on May 22, 2019

Dr. Hammer was very nice and comfortable to talk to. He listened and cared about what my concerns were. I will definitely see him again and refer him to others

Reviewed on May 22, 2019

Dr. Hammer is an excellent cardiologist and has a great personality in the office. He answered all of my and my wife's questions concisely. When I came to the clinic two months ago, I wasn't sure what could be done to correct my heart issues. Dr. Hammer provided me with realistic expectations and gave me peace of mind about my upcoming procedures and surgery. I wish I lived closer to the clinic.

Reviewed on May 16, 2019

Dr Hammer - the greatest cardiologist on the planet !

Reviewed on May 8, 2019

Dr. Hammer took his time talking to me and was very thoughtful on his answers. So far very impressed!

Reviewed on Mar 28, 2019

very knowledgeable in outcome analysis and as a Doctor is able to translate research and my clinical test results into actionable plans for my ultimate benefit. Felt very confident in all Dr Hammer's decisions concerning my needs for long term care of my arteries and heart.

Reviewed on Mar 28, 2019

the Cleveland Clinic heart is ranked number 1 due to its excellent staff and Dr Hammer is a great example of the quality of care provided by this hospital.

Reviewed on Mar 7, 2019

i love that Doctor Hammer up front honest and caring doctor

Reviewed on Feb 28, 2019

I had an excellent experience with Dr. Hammer.

Reviewed on Feb 28, 2019

I would highly recommend Dr. Hammer to any prospective patient.

Reviewed on Feb 28, 2019

I couldn't be happier with Dr.Hammer. I'm sure he has saved my life. He will always be thought of with the highest respect.

Reviewed on Feb 28, 2019

As I said earlier. I will recommend Dr. Hammer and the Cleveland clinic to everyone when heart health issues are discussed.

Reviewed on Feb 15, 2019

I was impressed by how much time the Dr. spent with me.

Reviewed on Feb 14, 2019

Dr. Hammer was very professional answered all my questions in great detail . Dr. Hammer was very prompt and very very reliable . Dr. Hammer is a very excellent Dr. I would recommend him to my friends and fellow workers.

Reviewed on Feb 1, 2019

Dr. Hammer was caring empathetic and showed genuine interest in helping me. He was thoroughl in his history taking and examination and listened to my concerns. He impressed me as an excellent clinician.

Related Videos Featuring Donald Hammer, MD

Related Videos Featuring Donald Hammer, MD

Back to Top