How successful is AF ablation?

Let’s talk about success.

At first glance, knowing whether a medical or surgical intervention achieves success seems quite simple. An antibiotic clears an infection–or it does not. A surgery removes a tumor with clean margins–or it does not. An angioplasty and stent open an artery during a heart attack–or it does not.

In the case of treating atrial fibrillation, however, it’s not like that. And this is especially true when one considers the use of catheter ablation–the biggest hammer in the toolbox of an electrophysiologist.

The doubters ask: why can’t it be simple? They say ablation cures other types of arrhythmia, such as supraventricular tachycardia (PSVT) and atrial flutter. In these cases, a patient is wheeled into your lab with an arrhythmia and wheeled out without it. Black and white. Success or not.

The confusion with AF stems from two big themes: One can be explained by looking at the definition of success:

 …the accomplishment of an aim or purpose.

When we speak about treating AF, aims and purposes are not as binary as whether an infection clears with antibiotics. I explain this to people using the aging analogy. Caregivers are not expected to cure aging, rather, we try to manage it. In many ways AF is the heart’s way of showing grey hair and wrinkles. (This is oversimplification, but allow me some leeway please.) So, at least in 2014, the aims and purposes of treating AF are often to manage it–gracefully.

It is true, sometimes we get lucky: a patient with AF hears our explanation; he stops inflaming himself, and, just like the patient with high blood pressure who starts exercises and stops overeating, the disease is rendered dormant. Did we cure AF or simply stave it off a decade or two?

That leads me to the second source of confusion surrounding AF: We simply don’t understand enough about what causes and maintains AF. A 34-year-old cyclist with an irregular heart beat has AF. So does an 80 year-old elderly woman with diabetes, arthritis, obesity and congestive heart failure. These two people are said to have the same disease, but surely they warrant different approaches to treatment.

Key-point alert: Treating a person is not the same as treating a disease.

Where I am going with this? What about AF ablation?

Last month, the highly influential academic cardiologist Sanjay Kaul said he wouldn’t be surprised if AF ablation turned out to be no better than a sham procedure. (Read the last paragraph of this post.)

I stewed about that comment for days. It got me thinking about the aims and purposes of AF ablation. What are we trying to do with this procedure? Are we looking to cure, as in eliminate all episodes of AF? Because if we could cure the disease that would greatly reduce the risk for stroke–a very “hard” outcome.

Or…is it enough to help another human being live a better life, one with less shortness of breath and better exercise tolerance, albeit with a continued stroke risk because of occasional AF breakthroughs? One’s view of this image surely depends on the perspective of his or her lens. When you can’t walk down the street because of breathlessness (perhaps due to the disease or its drugs), your aims and purposes change. Yes, 10-year stroke risk is important, but so is going to work next week.

Further, just because a procedure may not cure, should we withhold discussing it with a patient? How perfect does a procedure have to be? Who gets to judge that? Here we wade into deeply philosophical territory. How valuable is quality of life? What if a patient understands the risk of a procedure and is willing to accept the tradeoff? And this zinger: who gets to judge whether an $100K ablation is worth it?

A Twitter conversation I had recently sheds some light on these tough question.

Dr Prash Sanders (Australia) started the Friday evening discussion: (Ed note: an ILR is an implantable loop recorder–a $4000 USB-looking device that gets implanted under the skin in the chest. It records and downloads–with arguable accuracy–the heart rhythm for 36 months.)

His question gets to the issue of aims and purposes. When we ablate AF are we aiming to eliminate the disease, or, are we aiming to improve the quality of another person’s life? For if our aim is to cure AF, as if it is aging, we need more than a patient’s word that he feels better. (Perhaps we need a $4000 device made by a Fortune 500 company.)

Dr. Nassir Marrouchee (University of Utah) underscored the complexity of defining success of AF ablation:

Venture capitalist Dr.Justin Klein writes the word “dubious” in the same tweet as “reporting by patients.”

I’ve read somewhere that VCs like data:

With the ache of Dr Kaul’s sham-comment still buzzing in my head, I offered this to the doubters:

Dr Sanders closed the evening with this beauty:

—-

The next day, health policy expert Dr. Farzad Mostashari seemed to suggest that procedures need to do more than just improve symptoms and quality of life:

Dr Sanders nails it again:

There is much more to learn about both the disease AF. My guess is that as our knowledge of AF grows so will our aims and goals.

We may move from managing to treating. For now, helping patients with AF is a lot about managing aims and purposes.

JMM

Small things, big things

lisa+climbing

I ran up the hill. It seemed shorter, and less steep than I had remembered. I was barely winded at the top. I looked into the front office windows as I ran by the old high school. I don’t run fast anymore, yet the image was gone in seconds. My … [Continue reading]