An update on Atrial Fibrillation: Notes from HRS 2011

Earlier this month, heart rhythm professionals from all over the world met in San Francisco. I found the 2011 version of the Heart Rhythm Society meeting an incredible learning experience–a buffet of knowledge on all matters electric.

Here’s a book report of sorts on a few atrial fibrillation (AF) related issues:

From above the trees, looking down at the forest, the first point to make about the meeting’s content was that AF dwarfed all other topics. It wasn’t even close. Not only did AF topics dominate in the number of papers presented, these were also the best attended.

Not surprisingly, there were scant few talks on how to convince patients that lifestyle choices can help prevent AF. (That’s not what EPs do; we fix things once they occur.)

No one was talking about treating AF with rhythm-controlling drugs. There were only a couple of abstracts on Multaq, none of which showed anything positive. Thank goodness, let’s close this chapter and move on. People make mistakes.

It was a little surprising that the paradigm-changing blood-thinner, dabigatran, didn’t get much attention. I can’t help but wonder whether the heart rhythm community is already on board, or perhaps, it’s just too early yet (dabigatran was released just six months ago). To be honest, I’d like to see a little data on dabigatran from something other than the RE-LY cohort. Look for more on the safety of doing ablations on patients taking dabigatran in upcoming meetings.

The second most striking thing to report about AF was the lack of consensus on how best to ablate it in the EP lab.

As many know, AF severity is a continuum, with earlier stage disease having intermittent and self-terminating episodes and minimal to no structural heart disease. Later stages of AF are characterized by persistent (non-terminating) episodes which frequently ‘keep the company’ of a more stretched, scarred and dilated atria.

This distinction is important because the approach to AF ablation is different: earlier stage disease–in general–requires less burning than later stage AF. But even this simple and intuitive statement was contested amongst the experts.

Here we are more than ten years after the Bordeaux group described burning within a pulmonary vein to eliminate AF, and we still are not in agreement on how to best ablate AF. That’s striking–blog-able even.

At this year’s HRS, for instance, in one session, in one room, four leaders in AF ablation from across the globe presented significantly different strategies (and results) for ablating long-standing AF. You would think after a decade, there would be more agreement, or, that the strategies wouldn’t be so different. In this particular session, there were four speakers that detailed four different variations of AF-abalation; if there were ten speakers, we might have heard ten different methods.

Which strategy is best? Which expert is right?

It’s a tough call.

One camp advocates a minimalist approach, while others recommend more extensive ablation. Some believe that extra-pulmonary vein triggers (and drivers) of AF are common, and others don’t. Since both the smart bombers and the carpet-bombers report similar results, even doctors have trouble knowing which strategy is best. We are left to weigh the evidence and then…drum roll please…make a judgement!

At least we can all agree that pulmonary vein isolation forms the foundation for success, and strategies to make our burns (electric fences) more durable would be warmly welcomed.

That brings me to the final note. Here is a take-home message relevant to both docs and patients: getting rid of AF will be a journey–often a long one, frequently with creek-crossings, log piles and sheer drops. (Sorry, it’s hard to keep the mountain-bike similes at bay.) Seriously, I want to tell everyone who will listen: AF ablation works, but it is not Mickey-mouse!

Why such a journey?

Primarily because we don’t really understand the disease that well. AF is really complicated, and smart people are still learning about how best to approach such a diverse disease.

There was, however, unanimous agreement that AF recurs too frequently after successful ablation. It’s now okay to say, “multiple ablations may be needed.” For more advanced cases of long-standing AF, the chance of needing two procedures is more than fifty percent. What’s more, all of the experts now talk freely about the increasing number of patients requiring third, fourth and fifth ablation procedures. (As our “small pond” experience with AF ablation approaches its eighth year, third procedures are increasing in number, though we usually say ‘uncle’ after three.)

That’s all for now.

There were indeed other topics at HRS, including lively discussions about ICDs, as well as some interesting news on genetic testing for inherited disorders.

And of course, there was largesse.

JMM