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Posts Tagged ‘mechanical valves’

Heading out-of-town for a conference for a few days – but in the meantime, I’ll be working one several case reports from recent surgeries.

We will also be talking about the latest stories from the Heart.org about the recent rise in off-label use of dabigatran (Pradaxa) use.

Rise in Pradaxa (dabigatran) linked to off-label use

Off-label uses

While this new anti-coagulant has been touted as the ‘easy’ alternative to warfarin since serum monitoring is not required – it is currently approved for the use of non-valvular atrial fibrillation only in the United States.

While it is approved for deep vein thrombosis prevention (DVT prophylaxis) in Europe – it is not, and should not be used for anti-coagulation in patients with mechanical valves.  

Off-label use in Canada leads to life-threatening complications

However, that is apparently exactly how doctors in Canada have been using it – with life-threatening consequences.  In a separate article at the Heart.org, doctors report that two female patients with mechanical valves who were recently switched from warfarin to dabigitran suffered from valvular thrombosis.

The “easy button” strikes again

More concerning, these patients had previously been successfully managed on warfarin without problems prior to the switch.  (So they were taken off a drug that was working well – and switched to a drug that is not approved for this condition because it was perceived to be easier to use.)

Within one month of the switch both patients began experiencing symptoms and were then diagnosed with valvular thrombosis.  Fortunately, neither of these patients died – but they certainly could have.

My former boss had a saying, “the enemy of good is better” meaning that if we try too hard to improve on something that is already working  – we unnecessary risk the lives and health of our patients.

Anticoagulants are not all the same

This just brings home the message that drugs that may seem similar, aren’t.  The way that dabigatran works is very different that warfarin, aspirin, clopidogrel (Plavix), abciximab (Reopro) or the other myriad of anti-coagulation type drugs.  Some of these drugs work on platelets – some of these drugs work on different parts of a complex mechanisms of coagulation (the coagulation cascade).   ‘Anti-coagulants’ is just a blanket term for these medications – and certainly doesn’t fully cover the intricacies of the pharmacology involved.  ‘Easy’ it isn’t – but medicine rarely is.

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As part of our continuing discussions on Valvular disease, we are talking to Dr. Didier Lapeyre, a French cardiothoracic surgeon who currently resides in Switzerland.

if you look close you can see the valve leaflets

Talking with Dr. Didier Lapeyre, MD

I spent the morning talking to Dr. Didier Lapeyre, a cardiothoracic surgeon (via Skype). It was a fascinating discussion, and opportunity to ‘pick the brain’ of one of cardiac surgery’s elite surgeons and researchers. As we’ve mentioned before, Dr. Lapeyre is the ‘Father of the modern valve” and a true innovator in the field. His developments in artificial heart technology, mechanical valves and assistive devices have changed the field of cardiac surgery immeasurably, and have saved countless lives around the globe, so it was a pleasure and an honor to speak with him.  Since he is such an accomplished surgeon, and has such a wealth of knowledge, we had a lot of talk about.  It’s also too much to talk about in just one post, so I will be breaking into a couple of different discussions since it is such a great opportunity to bring to his many years of knowledge and experience to my readers here – which in itself, is a daunting but certainly worthwhile task. (It’s not everyday that I get to speak with one of the pioneers of the field).

I. Introduction to Dr. Didier Lapeyre

II. The Lapeyre devices and contributions to cardiac surgery

III. Current issues in cardiac valve replacement

IV. The future of valve replacement

But first, an introduction: Dr. Didier Lapeyre, MD, Cardiothoracic surgeon

Dr. Didier has spent the majority of his fifty + years in the field researching and developing valve technology and he is arguably, the expert in this field.  He has developed several heart valves and in addition to the current valve he is developing, holds five patents for these devices.  He also has four other patented artificial heart designs.  He is the Director and CEO of Lapeyre Medical LLC, and the former president and director of medical affairs for Triflo Medical Incorporated[1].

Learned from the best

After graduating from medical school at Claude Bernard University, Alexis Carrel Medical School in Lyon, France in 1957, he completed his general surgical residency at Claude Bernard University before becoming the chief resident in the cardiothoracic surgery program under Dr. Pierre Marion, one of the French pioneers in cardiac surgery in 1967.

Dr. Lapeyre then traveled to Rome, Italy and joined the department of surgery at the School of Medicine where he designed and developed a ventricular assist device for use in cardiovascular research.  He then returned to France in 1972 to work with Dr. Alain Carpenter, who is known as the father of mitral valve repair[2].  During the ten years he worked with Dr. Carpentier, Dr. Lapeyre helped to develop the first totally artificial heart.

Dr. Didier Lapeyre then headed the Aerospatial Total Artificial Heart Program, while he served as an assistance professor at the illustrious Texas Heart Institute.  While serving as a designer and medical officer at the Aerospatial program, he submitted four patents for his developments.

In 1987, he went on to work at another heart valve program, the Dassault – Aviation Heart Valve Program, which was affiliated with Texas Heart Institute.  While this seems like an unlikely partnership between heart surgery and aviation, during this period, Dr. Lapeyre submitted four patent applications for mechanical valves.

In 1996, he became president of Triflo Medical before establishing his own company in 2002, which is dedicated to the design, development and innovation of prosthetic heart valves.  He is currently working on a new artificial valve that addresses the current problems in existing technologies by eliminating the need for anti-coagulation.


[1] Dr. Lapeyre was previously involved in a legal action with this corporation in the ninth circuit court of the United States (central California).  Dr. Lapeyre ultimately won a multi-million dollar countersuit in this action.

[2] In 2005, Dr. Carpentier received the prestigious Medallion of Scientific Achievement from the American Association for Thoracic Surgery (AATS).  It was only the fifth time such an honor was bestowed, and the first time it was awarded to someone outside the United States.  (Other notable recipients include the mega-giants of cardiac surgery, Michael E. Debakey and rival, Denton Cooley.)

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