It’s time to write an update on AF ablation. Things have changed.
The major change is that I am doing many fewer ablations for AF.
The reason is we have a better understanding of the disease, or should I say, condition? In the last 2-3 years, good science has changed the way specialists see AF. The old-thinking had AF in its own silo. Your ECG showed AF so you had the disease AF. And if you had a disease, we had a fix–say drugs or ablation.
My partners would say, “John, we are sending you this patient with AF; please fix him.” And by fix, they meant drugs or ablation. Like a blockage–make it go away.
That’s not how AF treatment works. I’m surprised it took this long to figure that out.
The new thinking is that AF (often) occurs as a symptom or sign of something else.
Before I expand on that something else, let’s set out that there exists a small (but very vocal) minority of patients with AF that have no underlying disease or cause. This type of AF, the focal kind coming from an isolated source, usually within or around the pulmonary veins, was the type of AF first described by Dr. Michel Haïssaguerre and colleagues in the NEJM in 1998. If this was the only AF we ablated, AF ablation would be as curative as it is in supraventricular tachycardia.
It is not.
Most AF in developed countries is not a focal or primary problem with the heart. Most AF has a root cause outside the heart.
“Things” outside the heart that lead to AF include obesity, sleep apnea, alcohol, high blood pressure, inflammatory conditions (infections, trauma), excess exercise and probably stress. A blog post can’t explain the biology of how these signals affect the heart, but most experts now agree that each of these conditions, either alone or together, create the milieu in which AF starts and perpetuates.
The overly simplistic explanation goes like this: the above conditions (with inflammation and excess being the common thread) cause atrial chamber dilation, enlargement of individual atrial cells, loss of atria skeleton, change in cell membrane connections and deposition of scar. In total, we call these effects remodeling, and remodeling favors the development and persistence of AF.
We have always known to look for underlying causes of AF before treatment. In the past, though, this search was limited to conditions like high thyroid levels and valve issues.
What’s new now is the evidence linking lifestyle to disease in the atria. Dr. Prash Sanders and his team in Adelaide Australia have demonstrated that attention to risk factor reduction, such as weight loss, gains in fitness, alcohol modulation, and treatment of high blood pressure reduce AF burden–whether or not a patient comes to ablation. That last phrase is key: risk factor management bolsters AF ablation success rates.
When I see a patient with AF, I check for sleep apnea, discuss weight loss, alcohol intake and make sure we’ve got blood pressure under control. I also inquire about stress. A patient frazzled by the transient stressors of life–care-giving for a loved one, grief, or marital problems–will likely get better when the stress passes. What’s so fascinating about athletes with AF is that the excess exercise can have the same effects on the atria as does obesity–oh the irony.
The first step in AF treatment, therefore, is to focus on the root causes of AF. To do this, you first have to spend a fair amount of time removing fear. Patients with AF have to understand AF. They have to know AF is serious but not deadly.
For patients with ongoing symptoms, these long-term treatments must be combined with something now.
In the short-term, I use temporizing measures to relieve AF symptoms: drugs for rate control, anticoagulants for stroke prevention, and maybe even cardioversion with or without anti-arrhythmic drugs. The key is that these treatments are temporary. We aren’t shocking or medicating an AF patient with the idea that this is the fix; we are doing those things to buy time for risk factor management to work. And it does. I’ve seen it work.
Of course, in medicine not all things work perfectly. Risk factor management doesn’t always succeed. Here is where ablation still has a role–later, after we have given time a chance to heal; after we have given risk factor management a chance to heal, and most importantly, once we have gone slowly enough that patients aren’t having ablation out of fear of the disease or the mistaken belief that putting 60-80 ablation lesions in the left atrium is an “easy” fix.
Perhaps the coolest aspect of this new thinking is that even when we end up doing ablation, risk factor management not only improves success rates but it also makes the person healthier overall.
Since embracing this holistic approach to people with AF, I’ve done far fewer ablations and redo ablations.
The take-home message for patients and doctors alike is that AF ablation remains a reasonable option for carefully selected patients. But we should no longer rush to treat a condition caused by scar by creating more scar.
Go slowly; look for causes; treat these causes; give peace a chance. There is almost always a fix for AF. It’s rarely with a catheter alone.