John D Day



John D Day, medical director, Intermountain Heart Rhythm Specialists, Utah, USA, and second vice-president of the Heart Rhythm Society (HRS) considers that earning a degree in Mandarin before becoming an electrophysiologist has helped him to broaden and exchange his medical expertise to China. He spoke to Cardiac Rhythm News about his career achievements, the atrial fibrillation ablation programme at the Intermountain Heart Institute, his research on atrial fibrillation and Alzheimer’s disease and the key topics at the Heart Rhythm Society annual meeting (811 May, Denver, USA)

What prompted your decision to become a doctor and, in particular, why did you choose to specialise in electrophysiology?

Since I was seven I wanted to become a cardiologist. I am not really sure how this happened but it was something that was always part of me. I never really made the decision to be a cardiologist. However, the decision to specialise in electrophysiology did not come until my cardiology fellowship. I guess at the time I was influenced by the attending electrophysiologists at Stanford University, as well as my fascination with ablations, pacemakers and defibrillators.

In your view, what has been the most important development in electrophysiology during your career?

It has been in the field of atrial fibrillation. When I started my cardiology fellowship in 1997, we really did not have much to offer patients other than antiarrhythmics and warfarin. This was really frustrating as so many patients had problems with either the toxicities/side-effects of antiarrhythmics or the bleeding/lifestyle issues associated with warfarin.


It was shortly after I started my cardiology fellowship that the landmark article from Michel Haïssaguerre appeared in the New England Journal of Medicine in September 1998. Suddenly, there was the possibility of a potentially curative ablation approach for atrial fibrillation as well!

Still later in my career, the development of the new anticoagulants as well as a percutaneous strategy for left atrial appendage occlusion or excision completed the process. Now we have something more to offer patients than just antiarrhythmics and warfarin!

As someone who has been involved in various clinical trials, which piece of research are you most proud of and why?

The area of our research that I have been most proud of is our discovery from approximately 40,000 patients at Intermountain Healthcare (Murray, Utah, USA) that not only does atrial fibrillation significantly increases the long-term risk of dementia but that it is also an important cause of Alzheimer’s disease. Our follow-up research then showed that if atrial fibrillation could be eliminated by catheter ablation, then the excess long-term dementia/Alzheimer’s disease risk could be eliminated.

We have also come to learn that if an Alzheimer’s disease patient develops atrial fibrillation then his/her cognitive decline becomes particularly rapid. All of these studies point to the importance of maintaining a healthy cardiovascular system including the maintenance of normal rhythm in the prevention of long-term dementia and Alzheimer’s disease.

What are the main research priorities in electrophysiology?

One area in electrophysiology research where we have fallen short and need to focus our efforts is on preventing the disabling consequences of atrial and ventricular arrhythmias. At least 75% of my patients would not be patients if they had a healthy lifestyle. Most of what we all see everyday in our practices is totally preventable. With our current world fiscal crisis and ageing population we really need to focus much more research efforts in prevention.

What are your current research interests?

We are currently very interested in studying further the relationship between atrial fibrillation and dementia/Alzheimer’s disease as well as the prevention of atrial and ventricular arrhythmias.

Of the research you have seen in the past year, which did you find the most interesting and why?

I am most fascinated by the research from Dr Sanjiv Narayan and colleagues. For my entire career in electrophysiology, I have been very focused on catheter ablation of atrial fibrillation. While we have done an excellent job ablating paroxysmal atrial fibrillation, we really have struggled with the ablation of the persistent forms of atrial fibrillation.

If there really is something to “rotor” or “driver” ablation of atrial fibrillation, this could represent the Holy Grail of atrial fibrillation ablation! Atrial fibrillation could then become a focal ablation procedure much the same way as an ablation for supraventricular tachycardia.

You launched the atrial fibrillation ablation programme at LDS Hospital/Intermountain Medical Center. What are the main outcomes of this programme?

We are very proud of our atrial fibrillation ablation programme. We have performed approximately 5,000 of these atrial fibrillation ablation procedures with excellent results. We have published our outcomes on the first 4,212 patients who have had this procedure performed at Intermountain Healthcare and we continue to publish regularly on this very large cohort of patients.

You have been highly involved with the Heart Rhythm Society for more than 10 years. What are you most proud of?

I am most proud of the way the Annual Scientific Sessions have developed over the last 10 years. The meeting has grown tremendously and has continued to be very relevant to electrophysiologists and heart rhythm professionals. While other large cardiology meetings have suffered during this period of time, our annual meeting continues to remain a must attend meeting.

As vice chair of the Scientific Sessions of HRS 2013 and second vice president of the Heart Rhythm Society please tell us what the key themes of this year’s congress are?

This year’s theme is honouring our past and shaping our future. We truly stand on the shoulders of the giants who have been before us in the field of electrophysiology. It is in this great heritage that important discoveries have and will be made to shape our future.

We are particularly excited about former president Bill Clinton offering our keynote address at the Opening Plenary Session.


I am also particularly excited this year about our expansion of the Summits and Forums. This will be the first year we have offered both the Atrial Fibrillation (AF) Summit as well as the Ventricular Tachycardia Summit in the same meeting. In addition, we are offering a lead management forum as well as the basic science forum.

Live cases will continue to be an important aspect to this meeting and will feature some of the latest technology available. Cases that will be shown live this year include the cryoballoon for ablation of atrial fibrillation, the subcutaneous ICD, percutaneous left atrial appendage ligation, and rotor mapping of atrial fibrillation.

At HRS 2013 you will give a talk on “The five most important things to avoid complications with atrial fibrillation ablation”, could you tell us which is the most important thing and why?

Number one on this list is to protect the oesophagus. The rare occurrence of an atrio-oesophageal fistula is a catastrophic complication, which usually results in death or severe disability. The only way to prevent this complication is to limit energy delivery to the posterior wall. This can be a challenge as the posterior wall is a common location that needs to be ablated as part of a successful ablation procedure. There are certainly some techniques which can help and will be discussed at this lecture in the AF Summit.

Could you tell us what has your most memorable case been and why?

One case that comes to my mind is a 60 year old man with severe obesity and severe left atrial enlargement who suffered from many years of uninterrupted atrial fibrillation. He had tried many different antiarrhythmics all without success. He had also undergone two atrial fibrillation ablations without success. After each ablation or cardioversion he would only hold rhythm for a very short period of time. However, during these brief periods of sinus rhythm his breathing was dramatically improved which allowed him to be physically active without disabling shortness of breath.

On his third ablation for atrial fibrillation, we used the non-contact balloon mapping system to identify atrial fibrillation drivers based on a new technique that we have developed at our institution. After using this mapping, we were able to find several focal areas within the left atrium that were driving his atrial fibrillation. Ablation at these focal sites not only terminated his atrial fibrillation but it has also allowed him to continue to maintain sinus rhythm now almost one year later without the need for antiarrhythmic medications. Cases like this one have convinced me that for at least certain patients, focal ablation of atrial fibrillation rotors or drivers may be curative even in patients where traditional ablation approaches would have probably failed.

Before becoming a physician you earned a degree in Mandarin Chinese, how have these former studies contributed in your medical career?

Yes, I was a Chinese major at university before entering medical school. I have been fascinated with the culture, language, and Chinese people for the last 27 years of my life. This major, while it may appear has nothing to do with the field of electrophysiology, actually has been quite helpful. Each year I make at least one trip to China to lecture at various cardiac meetings. It has been fun for me to give my usual presentations in Chinese at these meetings. Also, it has allowed me to develop many close relationships with electrophysiologists throughout China.

It was through these relationships and my trips to China that I came to learn of China’s Longevity Village. This is a small village of just 530 people deep in the mountains of southwest China near the Vietnam border. Its residents often continue to do manual labour in the fields until their 90s and 100s. They live together in happy four or five generational homes. Heart disease is almost unheard of in this village, they do not take any medications or undergo any surgeries, and they do not develop the disabling diseases of ageing that we see in Western societies. In fact, it was my research of these villagers, particularly the seven centenarians in the village, in remote China that led to my upcoming book entitled “The Longevity Plan: Lessons Learned from China’s Longevity Village on How to Lose Weight, Feel Great, and Live Healthy to 110.”

You participated in a joint statement from six societies (SCAI/ACCF/HRS/ ESC/SOLACI/APSIC) on the use of live case demonstrations at cardiology meetings in 2010, could you tell us what are the pros and cons of this practice?

Live cases are an important aspect to the education of proceduralists. We all initially learned how to perform these complex procedures by watching our mentors. The same is true with live cases. The further out you are from training the more important these live cases become. So much can be learned from a live case as you can see into the head of these highly skilled operators as they encounter difficult challenges in real time.

Of course, the primary concern with live cases has to be for patient safety. Concern for the patient needs to come first. The operator cannot be distracted from the procedure and the best approach needs to be performed for the patient. With these important patient safeguards in place, live cases will continue to be a critically important component to ongoing physician education.

Outside of medicine, what are your hobbies and interests?


Outside of medicine, I love to spend time with my wonderful wife and three great children. We also love skiing together every week as a family or just being together in the mountains. I also have a passion for climbing mountains to ski or with my mountain bike in the summer. In fact, I regularly climb mountains with my skis or my mountain bike early in the morning before I start my first ablation at the hospital at 7.30 am!


Fact File

Current appointments

-Medical director, Intermountain Heart Rhythm Specialists, Intermountain Heart Institute, Murray, Utah, USA

-Visiting professor of Cardiology, Dalian University, Liaoning, China

-Second vice-president, Heart Rhythm Society

-Board of Trustees, Heart Rhythm Society

–Editor in chief, The Journal of Innovations in Cardiac Rhythm Management


1999–2001 Cardiac Electrophysiology and Arrhythmia fellow, Stanford University Medical Center, Stanford, USA

1997–1999 -Cardiovascular Medicine clinical fellow, Stanford University Medical Center, Stanford, USA

1995–1997 -Internal Medicine resident, Department of Internal Medine,Stanford University Medical Center, Stanford, USA

1991–1995 -Doctor of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland

1985–1991 BA, Mandarin Chinese; Graduated Magna Cum Laude Brigham Young University, Provo, Utah, USA

Honours and awards


2012 -International Friendship Award, China Society of Pacing and Electrophysiology

2008 -International Cooperation Award, Great Wall International Congress of Cardiology, Beijing, China

2001–2002 -Outstanding Faculty Teaching Award, Department of Internal Medicine, University of Utah School of Medicine


Fellow, Heart Rhythm Society (2008–present)

-Fellow, American College of Cardiology (2003–present)