Julie B. Shea, NP
Atrial fibrillation is an abnormal heart rhythm that affects anywhere between 2.5 and 3 million Americans annually. It’s a rhythm disturbance that affects the upper chambers of the heart which are known as the atria. When the patient goes into atrial fibrillation, they actually get a quivering of the upper chambers. So normally, during normal conduction, the atria will squeeze and relax and fill the lower chambers. However, when the patient’s in atrial fibrillation, they get this quivering type pattern. And the result of that is that it can make the heart beat very rapidly and irregularly.
Atrial fibrillation can cause a variety of symptoms. And it actually occurs along a continuum. On one end of the continuum we have patients who are highly symptomatic. So they know the second that they go into atrial fibrillation, they feel the palpitations; they feel the irregularity of the heart. They just become acutely symptomatic. And then, we have patients on the other end of the spectrum who have absolutely no awareness, whatsoever, that they’re in atrial fibrillation. So they may walk into their doctor’s office for a routine office visit, where the doctor notices that their heart rate’s going 180 beats per minute. And they have absolutely no awareness of this.
Most patients, however, fall within that continuum, from either mildly to moderately symptomatic. Some of the symptoms include palpitations, lightheadedness, activity intolerance. But typically what we see are the feelings of shortness of breath and fatigue are most commonly symptoms felt by most patients.
Diagnosing atrial fibrillation is actually quite easy. All it requires is an electrocardiogram in the doctor’s office. And we can easily see that you’ve gone into atrial fibrillation. Some of the EKG characteristics that we look for are the presence of an irregular heart rhythm.
When patients are diagnosed with atrial fibrillation, they're sometimes referred to an electro physiologist, which is a board-certified cardiologist who is specialized in the management of patients with heart rhythm disorders. I think it’s important to remember, when you're dealing with patients with atrial fibrillation, is that each patient is treated as an individual.
Now the different treatment options that are available, most commonly are medications. These are typically the first line agents that we use to treat atrial fibrillation. So, as healthcare providers, when we’re thinking about how we’re going to manage someone with atrial fibrillation, we have two predominant goals in mind. First and foremost is to prevent stroke. That is one of the leading causes, or the leading co-morbidities of atrial fibrillation. And oftentimes, that’s the initial way patients present with atrial fibrillation, is that they’ve come in having had a stroke. So the use of blood thinners is first and foremost.
The second piece that we look at is heart rate control. As I mentioned that the atria, when you're in atrial fibrillation, can be beating anywhere from three to 400 times per minute. We know that patients who have rapid ventricular rates like that, over a period of days or weeks or months, they can actually develop a weakening of the heart muscle called a cardiomyopathy. So again, controlling the heart rate and preventing it from going too fast in atrial fibrillation is another important consideration. So we use drugs such as beta blockers or calcium channel blockers to help the AV node work more efficiently, thereby slowing down the pulse.
So it’s important when you are trying to decide upon what type of treatment is best for you, to have a detailed conversation with your electro physiologist to decide whether medical therapy would be a better option for you, or whether you would be a suitable candidate for treatment with ablation therapy. As it stands, typically in order to qualify for an ablation procedure, you would have at least had to be tried on an anti-arrhythmic medication and failed that medication.
However, the thought process of this is evolving. And there's actually a clinical trial going on currently called the Cabana Trial, which Brigham and Women's Hospital is a participating center of. That actually is doing a direct comparison of catheter ablation to the use of anti-arrhythmic medications to see which is a superior treatment for patients.
Within the field of electrophysiology, we have learned so much about atrial fibrillation and the mechanisms behind it. However, there's still a lot we don’t understand. Things like genome therapy, looking at the genetics of atrial fibrillation, and you know, why a 34 year old individual would develop atrial fibrillation with no known risk factors. These are important things that are being researched currently. The technology is continuing to evolve. Different catheters are being developed that will allow the users to specifically target tissue areas better, provide for better delivery of different types of ablative therapies, such as radiofrequency, energy or CRYO therapy. New mapping technologies are continuously being developed.
So there's a lot of research going on, both around the world and here at Brigham and Women's Hospital, looking at ways to provide you with the best care we can for managing your atrial fibrillation.