Friday, March 20, 2009

Living With Atrial Fibrillation

I read this recent article by New York Times business writer Duff Wilson regarding his mother's difficulties managing atrial fibrillation: the need for anticoagulation, ineffectiveness of cardioversion, the side effects of the antiarrhythmic drugs, and her indecision regarding future drug or device therapies. For now she has decided leave her rhythm alone and (hopefully) stick with just anticoagulation. For some, doing nothing might just be the best option, provided the heart rate is well-controlled.

Our drugs are just not that effective for atrial fibrillation. Any of them. Even the upcoming dronedarone. Certainly some may work better in some patients than others, but once you fail one drug (especially amiodarone), the odds of having long-term success with another drug is limited (dofetilide might be an exception here, but can only be used in patients with normal or near-normal kidney function).

Sometimes, though, I find its helpful to try to determine what causes some one's fatigue. Is it the rapid heart rate, the irregularity of the heart rhythm, or the loss of mechanical synchronization between the atria (top chambers) and the ventricles (bottom chambers) of the heart.

If the patient complains of racing heart rhythms, then using rate control medications like beta blockers or calcium channel blockers may be all that's needed to improve their symptoms.

If the patient complains that the irregularity of the rhythm is what bothers them, then there is a good chance that a pacemaker might improve their symptoms since their rhythm can be regularized after implanting the pacemaker and then ablating the AV node. While this has the downside of rendering someone pacemaker-dependent for their heart to beat, in the older age group, this therapy has been shown to demonstrate marked improvement in symptoms with only the need for ongoing anticoagulation without the potential side effects and toxicities of antiarrhythmic medications. In the older crowd, this might not be such a bad option.

Finally, if the person's primary complaint centers on fatigue, there are two options: (1) do nothing and continue anticoagulation (since fatigue may be a difficult symptom to resolve) or (2) consider catheter ablation of the atrial fibrillation - provided the risks of the procedure are carefully reviewed. In a small subset of patients, octogenarians were thought to be as safely treated with catheter ablation as younger adults. This study was limited, however, by its retrospective design and limited numbers. What has not been shown yet is a mortality advantage to this approach and certainly there are plenty of risks with this procedure.

Finally, the need for follow-up after any one of these therapies is undertaken might vary and influence which therapy to recommend. The take-home message here is that no two patients' needs are alike and sometimes it's tough to always make the "perfect choice."

Anyway, just some thoughts. It'd be interesting to read what others might recommend.

-Wes

6 comments:

Anonymous said...

Dr. Wes,
Do you have any thoughts about the MAZE procedure? I spent several weeks last summer tracking down patients who had it done at my institution, to get long-term follow-up for a study. Most of the patients I talked to were happy with their results, and a sizable group just went on and on about how much it had changed their lives. On the other hand, it seemed like a lot of them, especially those who had the surgery in the early days, were relatively young and healthy, aside from the atrial fibrillation.

DrWes said...

Xerxes1729-

The surgical MAZE procedure has many varieties, but the common theme in each is the creation of non-conducting lines in the atria using surgical techniques. As such, these procedures involve entering the chest cavity, be it by a full sternotomy (through the breastbone), lateral thoracotomy (between the ribs on the side of the chest) or via a scope with smaller incisions on the side(s) of the chest. All of these procedures cause one or both lungs to collapse. After the procedure, one or more chest tubes are inserted into the chest after the procedure and connected to vacuum suction to help re-inflate the lung(s). Therefore, recovery with this procedure takes a few extra days compared to catheter-based procedures (which are done entirely through the veins).

There are also various types of Maze procedures: the typical "cut and sew" Maze, creation of these lines with radiofrequency lines using unipolar (Boston Scientific’s Thermaline probe) or bipolar (Atricure) energy sources, ultrasound lines (St. Jude's Epicor system), and cryoablation (freezing), to name a few.

While most surgical techniques are effective, and in some cases might be slightly more effective than catheter-based procedures, they all still have a significant recurrence rate, sometimes carry a need for permanent pacemaker after the procedure, and often require follow-up catheter-based ablation procedure(s) to get rid of other complicated atrial arrhtyhmias created by incomplete ablation lines. (These can occur with catheter-based afib ablation procedures, too).

Because of the relatively invasive nature of surgical Maze procedures and the associated pulmonary issues involved, typically younger, healthier patients are more likely to be referred for this more invasive surgical approach. Younger patients, by their relatively healthy nature compared to folks over 80, typically have more favorable outcomes compared to their octogenarian counterparts. Interestingly, bother catheter-based and surgical procedures have good outcomes in paroxysmal (intermittent) atrial fibrillation, but poorer results in patients with chronic (permanent) atrial fibrillation. (By the way, patients who do not feel their atrial fibrillation (i.e., are asymptomatic) should not be referred to EITHER procedure, in my opinion.)

Not all surgical ablation techniques (or clinical circumstances) are created equal, so people would be well-advised to discuss their individual situation with their doctor(s) and consider getting a second opinion. Certainly, I would hope that people do not listen entirely to this doctor’s opinion (yeah, mine) who knows nothing about your particular clinical situation.

Just my $0.02.

Anonymous said...

Hey doc - I have a question. Has there been an increase in cases of AFib? Seems to me every time I turn around I run into someone else being diagnosed with it.

DrWes said...

Anony 11:18-

I'm not really sure if there's been an increase in cases of atrial fibrillation lately. More likely, we're all getting older and the incidence of afib increases with age...hence, we tend to see more of it as we walk along the path of life...

dhmosquito said...

Dr Wes--I consider myself fortunate, as a 56 yr male paroxysmal ATF patient (primarily nocturnal & highly symptomatic; prevented me from sleeping), to have had good luck with flecainide, 100mg daily. It took me a while to determine that there are 2 types of cardiologists: "plumbers" and "electricians". Once I determined that I needed what I found out was your specialty, a Cardiac Electrophysiologist, and once my doctor got a good "capture" on a Holter Monitor, he prescribed the flecainide after the nuclear stress test and an echocardiogram, and I never looked back. Five years later, and a second stress test, no problems. Hopefully the medication, which is thankfully generic, will continue to work well. For me, at least, it's a triumph of modern pharmacology. I enjoy your commentary on this blog; you've referred me to a number of informative sources that have helped educate this engineer as to what ATF is all about. Keep up the great work!

Anonymous said...

Had a pacemaker 5 years ago because of sick sinus syndrome. Have been feeling tired and weak, never got my old health back. Now have atrial fib. Need lopressor and aspirin for now.
I thought a pacemaker is used for Afib. I am confused. More tired than before.
Should I seek the advice of an Electrophysiologist.