Michel Haïssaguerre

1192

Michel Haïssaguerre, electrophysiologist, chairman of the International Symposium on Catheter Ablation Techniques, speaks to Cardiac Rhythm News about how he started in the specialty, the French Bordeaux group and his actual research.

Why have you chosen a career in medicine?

I was brought up in a small village at the base of the Pyrenees, in the Basque country. No one in my family was in medicine, indeed they were working in the countryside or in commerce. As a child I loved visiting the old chateaux, ruins and caves from my region and I wanted to be an archaeologist. However, in my late teens, I inclined towards psychology, and so entered medical school with that interest in mind to become a psychiatrist.

 

What brought you to electrophysiology (EP)?

It was in 1979, as a second-year intern in cardiology, that I discovered my passion: electrophysiology. I owe my introduction to the specialty to Professor Warin, then the head of the cardiology service at the Hôpital St Andre in Bordeaux. Professor Warin was working at the beginning of a French group of rhythmologists (with Puech, Coumel, Fontaine and others) and although this is not well known, he was the first to describe idiopathic fascicular VT (inducible by atrial or ventricular stimulation). I learned about the world of electrophysiology in his department. I became fascinated that, from the examination of a simple 12-lead ECG trace, it was possible to deduce an invisible electrical mechanism operating within the heart. We could often manipulate the arrhythmia and understand its mechanism by electrophysiological mapping.

 

Professor Warin recommended me to Dr Philippe Coumel, Professor of Cardiology at Lariboisiere Hospital in Paris at this time. This happened in 1980, at the dawn of interventional electrophysiology – electrophysiology was moving from a purely diagnostic speciality to a curative speciality. Scheinmann and Gallagher had recently reported their initial experience of fulguration of the His bundle by intracardiac application of a DC shock. Their results were magic to me. Not only could we describe and debate a putative mechanism, but we could now prove the correct one while at the same time treat the condition.

 

In 1982, I returned to Bordeaux to work with Professor Warin as senior resident. Three weeks later, we saw a young man with ventricular fibrillation and an accessory pathway. After nine hours of mapping, we successfully fulgurated his accessory pathway. This began our series of fulguration of accessory pathways rapidly growing with patients referred from all of Europe. Later on, we had the opportunity to perform the initial intracardiac fulguration of Mahaim fibers and atrioventricular nodal tachycardias. The use of DC was a hard school because the catheters were not steerable and only two shocks were allowed for safety reasons (compared to current day practice of multiple RF energy applications). Thus 98% of time was devoted to precise mapping of the electrophysiological parameters, to be sure that we were at the site of earliest activity, the true accessory pathway potential, the optimal unipolar potential etc. This paved the way to current day practice of treating these arrhythmias.

 

Who were your main professional influences?

I believe we are influenced by all the exceptional electrophysiologists around the world who have contributed to our speciality. After Professor Warin died, I moved from the inspirational department of Professor Coumel to Hôpital Cardiologique du Haut-Lévêque. This was under the kind direction of Professor Jacques Clementy, who gave me total freedom to pursue my passion.

 

What do you consider your greatest achievement so far?

Elimination of accessory pathways and AVNRT – both linked to discrete structures –by a catheter transmitting energy whatever DC, RF or cryo energy was a great improvement compared to surgery but conceptually this was a gradual progression.

 

In contrast, cardiac fibrillation – atrial or ventricular – was described as a chaotic or incessantly changing substrate, which seemed at first sight inaccessible to ablation. The merit of our group, including Pierre Jais, Dipen Shah, Meleze Hocini and many bright and passionate colleagues from around the world, was to demonstrate that many fibrillations were associated with discrete structures, the PVs in AF and the Purkinje network in VF.

 

Ten years ago, in 1998, your group, the French Bordeaux group, published a groundbreaking article demonstrating how atrial fibrillation (AF) is initiated by ectopic beats in the pulmonary veins. This article helped develop catheter ablation as it is performed today and many patients have been cured of AF thanks to this pioneering research. How did you get involved with this?

At the time the gold standard treatment for atrial fibrillation was Maze surgery, which was designed to sever the atria into compartments, directing the electrical impulse along discrete channels.

 

Whilst we were attempting to emulate the Maze procedure, we fortuitously observed the spontaneous initiation of atrial fibrillation and isolated ectopy, with the same morphology as the initiating beat of atrial fibrillation, on the 12-lead ECG. This led us to track these elusive ectopic beats, and finally after many hours each day (sometimes all day) we found that the sources of paroxysmal AF were the pulmonary veins.

 

So, in total contrast to the general belief that any atrial site could generate atrial fibrillation, we found that in most cases the sources of ectopy were clustered around venous tissue. More surprisingly, the electrical impulse came from a simple venous conduit that was believed to be electrically inert (thus of no possible interest to an electrophysiologist…).

 

From these beginnings, atrial fibrillation ablation has grown rapidly and its various mechanisms are now the focus of research and targets for therapy worldwide. In chronic atrial fibrillation, the contribution of the pulmonary veins is lesser because of the importance of other cardiac structures, such as the coronary sinus and the left atrial appendage.

Interestingly, the observation of a discrete structure initiating and maintaining atrial arrhythmia can be applied to the ventricular tissue.

We reported that ventricular fibrillation in normal hearts, as well as in ischaemic heart disease, is driven from the Purkinje network – the specialised conducting system representing only 2% of the ventricular mass. Again, ablation of these sources is very effective in eliminating ventricular fibrillation in those patients with frequent episodes.

 

What differentiates the Bordeaux Group’s approach to treatment from other groups?

We are always trying to learn from our patients with the hope of improving our understanding of arrhythmias. The humble 12 lead ECG is still of interest. Over the past 10 years we noticed that a lot of patients with idiopathic VF had so-called early repolarisation in the inferolateral leads of the surface ECG. By talking to my many colleagues throughout the world, we found out that this phenomenon occurred in 30% of patients with idiopathic VF, compared to only 5% of the general population, thus providing the beginning of an explanation for idiopathic sudden death.

 

What areas of research are you investigating at the moment?

We have many areas of ongoing research, but our major focus is on the fibrillating heart, and the mechanisms underlying fibrillation. As well as trying to understand chronic AF and VF, we are actively investigating specific pharmacological treatments and diagnostic test for patients with early repolarisation and VF, including those with the concealed form of this condition.

 

Additionally, we are trying with genetic centres to determine the genetic mutations responsible for these changes, and so far the group from Nantes has identified new mutations in two ion channels. Through the greater understanding of the molecular basis of arrhythmias we may be able to determine exactly which patients are at risk and develop specific treatments for them.

 

Finally, we are working with our colleagues in industry to develop new tools to facilitate both mapping and ablation.

 

In your opinion, is EP in France and Europe behind or ahead the developments of the discipline in the US?

In today’s society when we can communicate with email, and with our publications published online, the whole world advances at the same pace. There are many active groups contributing to our understanding throughout the world.

 

You are also actively involved in education, being the chairman of ISCAT (International Symposium on Catheter Ablation Techniques). Given that technology is evolving very quickly, do you believe that education has a more relevant role in EP than in other areas of medicine?

Education is important in all areas of life, not just medicine, and not just EP. The technology we use on a daily basis is evolving very quickly. When I started in electrophysiology each case would use reams of paper that we went over with callipers, whereas now we have computer based systems, 3D imaging and robotic manipulation of catheters. However, the fundamentals of EP have not changed, based on signals emitted by the heart. We need to understand the basic principles so that we can make optimal use of the many technologies available.

 

How do you envisage the future of EP? What can we expect as the next step in catheter ablation for AF?

At the start of invasive EP, we were happy to spend all day mapping an accessory pathway prior to fulguration. Nowadays, if an electrophysiologist spends more than 15 minutes ablating an accessory pathway, he is unhappy. We hope that the rate of progress will be similar to shorten the time required for mapping and ablation of AF.

 

What are your interests outside medicine?

I like to restore ancient houses and buildings. For example, I spent three years restoring a16th century convent. I try to find original materials to replace features that have to be replaced, so that the building is as original as possible.

 

Fact file

 

Born
5.10.1955, in Bayonne, France

 

Medical studies and hospital/academic appointments
1979–1984 – Intern at Hôpitaux de Bordeaux
1982 – Masters in Human Biology
1982 – Doctor of Medicine
1984 – Assistant physician at Hôpitaux
1984 – Certificate of Special Studies in Cardiology
1987 – DEA Biology-Health
1988 – Physician at Hôpitaux de Bordeaux
1994 – Professor of Cardiology

 

Societies memberships
Associate member of the French Society of Cardiology since 1984
Member of the Rhythmology Group of the French Society of Cardiology since 1984
Member of the Rhythmology Group of the European Society of Cardiology
Member of the North American Society of Pacing and Electrophysiology since 1994

 

Reviewer of the following journals
Annales de Cardiologie et d’Angéiologie
Archives des Maladies du Coeur et des Vaisseaux
European Heart Journal
Pacing and Clinical Electrophysiology
Circulation
Europace
Journal of Cardiovascular Electrophysiology
Journal of the American College of Cardiology
Heart Rhythm
Nature Medecine
Journal of Interventional Cardiac Electrophysiology
Circulation Electrophysiology
Circulation Japan

 

Awards
Prix Robert Debré (1982)
Prix Ela Medical (1988)
Prix de l’Information Cardiologique (1990)
Prix Ela Medical (1992)
Nylin Prize 2002 (Swedish Society of Cardiology)
Best Scientist Award Grüntzig 2003 (European Society of Cardiology)
Best Scientist Award 2004 (North American Society of Pacing and Electrophysiology)

 

Publications
342 scientific publications, particularly on Electrophysiology and thermoablation of cardiac arrhythmias

(Visited 470 times, 1 visits today)