Hugh Calkins

Why did you decide to become a doctor and in particular, why did you choose to specialise in electrophysiology?

I decided to go into medicine when I was a teenager growing up in the small town of Hamburg, New York, which is a suburb of Buffalo. Both my parents are physicians. My father, a rheumatologist, was chief of Medicine at the University of Buffalo and my mother was a general physician at a psychiatric hospital in Gowanda, New York. I am the sixth of their nine children. Three of us (of the children) went into medicine.

When I started my cardiology fellowship at Johns Hopkins, I was initially interested in heart failure. However, during my first year of fellowship, I met Joe Levine who was an attending physician on the electrophysiology (EP) Service. He convinced me that EP was the most interesting field to pursue and took me under his wing. We designed several research studies, one of which resulted in me being the recipient of the North American Society of Pacing and Electrophysiology (NASPE) Young Investigator Award. It was this experience that helped fuel my interest in an academic career.

Who in your career has had the greatest influence on you and why?

I have been very fortunate to have worked with a long list of superstars in cardiology and electrophysiology. Some of these individuals include (ordered by institution and chronological date): Jeremy Ruskin, Warren Harthorne (Massachusetts General Hospital), Michel Mirowski, Myron Weissfeldt, Ken Baughman, David Kass, Tom Guarnieri, Jeff Brinker, Gordon Tomaselli, Ron Berger, Joe Levine (Johns Hopkins), Fred Morady, Alan Kadish (University of Michigan), Eric Prystowsky, Sonny Jackman, Frank Marcus, Al Waldo, Doug Zipes, and many others from the broader EP community. I recognise that this is a very long list. Any success I may have enjoyed did not happen in a vacuum. I was very fortunate and was provided outstanding opportunities.

It is very difficult to rank each of these individuals in terms of their influence on my career. But if I was forced to identify two individuals that I would want to especially acknowledge, it would be Joe Levine who convinced me to go into EP and helped foster my early research experience and Fred Morady. I spent two months as a visiting fellow at the University of Michigan in 1988. I was lucky enough to join their faculty in 1989.

During my first year on the faculty, I worked as a fellow in the EP lab under Fred Morady. Fred was a remarkable teacher and role model. Much of what I have learned about EP and about being a physician and an academic electrophysiologist, I learnt from Fred. He is a great teacher, a great electrophysiologist, and a great friend.

In your view, during your medical career, what has been the most important development in the management of heart rhythm disorders?

I would have to vote for radiofrequency catheter ablation. The field really began when I joined the faculty at the University of Michigan in 1989. You cannot imagine the excitement associated with performing our radiofrequency first ablation procedures for Wolff Parkinson White syndrome, atrioventricular nodal re-entry tachycardia and ventricular tachycardia. My second vote would be for the implantable defibrillator.

When I arrived at Johns Hopkins in 1986, implantable cardioverter defibrillators (which were referred to as AIDs at the time) were being implanted in the operating room by Levi Watkins on a regular basis. It was remarkable to see how nonthoracotomy lead systems revolutionised this therapy.

Your list of research activities is extensive with more than 400 published manuscripts. Which piece of research are you most proud of?

I am most proud of my research on two topics. The first is catheter ablation. As I mentioned above, I was on the scene when the field was in its infancy and I was provided with material to write clinically oriented manuscripts. These manuscripts, which I wrote with Fred Morady, helped to define the field of radiofrequency ablation. In 1991, I was the first author of a paper published in the NEJM, titled “Diagnosis and Cure of the Wolff Parkinson White syndrome or paroxysmal supraventricular tachycardias during a single electrophysiologic test” (N Engl J Med 1991; 324:1612–18). Fred Morady was the senior author.

This was a great moment. Since these early days, my interest in catheter ablation has continued. My research has focused on catheter ablation of all types of cardiac arrhythmias including atrial tachycardia, atrial flutter, and ventricular tachycardia. For the past decade, I have focused predominantly on catheter ablation of atrial fibrillation. The second body of research which I have been particularly proud of is my series of publications on arrhythmogenic right ventricular dysplasia (ARVD). I got interested in this disease 14 years ago and since then have had a wonderful time examining interesting questions concerning the diagnosis and management of ARVD. Our database now contains information on more than 1,000 patients.

At Boston AF, you reviewed the 2012 update of the 2007 HRS/EHRA/ECAS consensus document on atrial fibrillation ablation. Logistically, how did you ensure that all views of the writing committee members and societies involved were considered and that a consensus was reached?

Last year (2011), I had the opportunity to lead this joint effort by the HRS, EHRA, and ECAS. Karl-Heinz Kuck and Riccardo Cappato helped lead this effort with me. We used anonymous surveys to identify where there was and was not a consensus. The process began by having the 45 members of the writing group submit questions to be included in anonymous surveys of the group. All members of the writing group were responsible for answering each question and also to add comments. We then examined the responses to determine where there was and was not a consensus. We also included this information throughout our manuscript. In the section where we discuss sedation, for example, we included a sentence that approximately 50% of writing group members routinely perform atrial fibrillation ablation procedures under general anaesthesia.

You said that the most important change in the document is probably that there is now a class and level-of-evidence designation for each indication for ablation for atrial fibrillation. Why is this the most important change and why was it felt necessary to add it?

These changes reflect the fact that there is now a very large body of literature that has defined the outcomes of atrial fibrillation ablation.

Another important change is that the document now has updated recommendations on anticoagulation therapy. Of these updates on anticoagulation therapy, what do you think is the most important “take-home” message?

One of the most important is the acknowledgement that it is now very reasonable to perform an atrial fibrillation ablation procedure in a patient therapeutically anticoagulated with warfarin. Another important message is that a patient’s stroke risk profile, and not the perceived presence or absence of atrial fibrillation, should be used to guide decisions regarding long-term anticoagulation therapy following catheter ablation. This reflects the fact that atrial fibrillation recurrences are not uncommon following ablation, that recurrent atrial fibrillation may be asymptomatic, and that patients “pick up” stroke risk factors over time.

The new document also recommends that the CHA2DS2-VASc score is used to assess the risk of stroke in patients with atrial fibrillation. What are the additional benefits of this system compared with the CHADS2 system?

I am convinced that the CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischaemic attack, vascular disease, age 65–74 years, sex category) score is superior to the CHADS2 scoring system. This reflects the fact that many patients who have a CHADS2 score of 1 remain at significant risk of a stroke. The CHA2DS2-VASc score helps divide these patients into those with a higher and those with a lower risk of stroke. This information can then be used to guide decisions about anticoagulation. I recognise that some in our field find that general cardiologists cannot even remember the CHADS2 scoring system and that it would be a mistake to teach them an even more complex system. I am more of an optimist in this regard.