Interviewer: We are here with Dr. Jared Bunch, professor of medicine and section chief for electrophysiology at 91麻豆天美直播. Now, Dr. Bunch, when it comes to atrial fibrillation or AFib, what exactly is happening with the patient, and what are they experiencing?
Dr. Bunch: That's a great question. Atrial fibrillation is the most common abnormal heart rhythm that's sustained or maintained that we see in practice. I suspect most people who are listening to this know somebody that has atrial fibrillation. One in three of us to one in four of us will develop it. In fact, we live long enough, we live over 80, 40% of us will develop atrial fibrillation. And what it is is it's an abnormal electrical rhythm in the upper heart chambers, and these upper heart chambers normally beat in a really ordinary synchronized manner at 60 to 70 beats per minute. Atrial fibrillation replaces that maybe to 300, 350 beats a minute, the upper heart chambers. And that can cause stroke, it can cause heart failure, and it can cause a lot of symptoms such as chest pains, shortness of breath, dizziness, exercise intolerance, anxiety, fatigue. You may know somebody that has atrial fibrillation that called 911 the first time they developed it. In some people, the symptoms are more mild. So it's a symptomatic abnormal rhythm that's quite common amongst us.
Interviewer: And the potential for stroke, that sounds pretty serious.
Dr. Bunch: That's our biggest worry is stroke, because these upper heart chambers aren't squeezing and pushing the blood forward. So the clots that form can be larger than other sources of stroke and cause more disability and higher risk of death. So we really focus on trying to prevent stroke as an upfront treatment strategy.
Interviewer: Now, you said that some people live with AFib their whole life, and maybe it shows up at a physical or another kind of doctor visit. And other people, they feel it, and then they call 911, and they come in. Once a patient knows that they have some sort of AFib, what is the next step, and what are some of the treatments that can help kind of alleviate those symptoms or treat the disorder?
Dr. Bunch: So we look at this in three primary pillars, three primary treatment approaches. First, we want to prevent stroke, and our best way of doing that is early use and appropriate use of anticoagulants. They're often sometimes called blood thinners, but really they don't thin the blood. They make it slower to form a clot. So they're less likely to form a clot in the heart. And they can reduce the risk of stroke less than 1% a year, or it can be as high as 5% to 10% a year.
Our second concern is the heart is just a muscle. If the heart's going too fast or too long, it can begin to dilate, weaken, just like any of our muscles. And so we use medications to slow the heart down if needed. We want the average heart rate less than 100 beats per minute on average at rest. Sometimes we need to control it with exercise as well.
And then, finally, we focus on symptoms. Some people aren't aware that the symptoms they're experiencing is related to atrial fibrillation. They don't put that correlation together till we make the diagnosis. Other people know right away. So then we begin treatments to restore the heart rhythm really to help you feel better and do better and enjoy your quality of life at a higher degree.
Interviewer: Are there any kind of treatments that could potentially fix the kind of problems that they might be seeing that goes beyond, say, medications or some of these other things you've talked about?
Dr. Bunch: There's three primary ways that we treat this. First, we work on risk factor modification. What causes atrial fibrillation? The most common causes in the community, the most common we can't do anything about, we get older. It's a disorder of aging. But the other things we can do a lot about and that is high blood pressure, getting our blood pressure well-controlled, screening for sleep apnea when we hold our breath at night and treating that, decreasing alcohol intake, treating diabetes better, losing weight, and being more active. We want people to be active 30 to 60 minutes a day, that's the dedicated time towards activity, whether that's walking, jogging, running, swimming, yoga, whichever you like. It's important to have that time where we exercise our bodies.
So that is one part that we do to help lower the risk of atrial fibrillation. In fact, if we do those things really well, it will lower atrial fibrillation by 30%. We have medications that help force the heart to beat normal, what we call anti-arrhythmic drugs. And there's a number that are currently available, and we can use them depending on the health of your heart. So sometimes we can use a lot if your heart's healthy. If your heart's weak or you've had heart attacks or surgeries, then there's only a few we can use.
Then, finally, there's approaches to do this without medication. So the most common is called catheter ablation, and that's a procedure where . . . it's a minimally invasive procedure where we advance little specialized tools that are flexible and move in your heart called catheters through the veins in your leg up into your heart and cauterize around the sources of fibrillation and block them. These electrical sources are like throwing a rock into a pond. The waves carry from outside from where the rock enters throughout the whole leg. We want to block these signals at their origin. And then sometimes also, if needed, the same procedure can be done by our surgical colleagues through open-heart surgery in patients with really advanced heart disease or disease that we can't get to from within the vessels.
Interviewer: So what kind of patient is best served by the cardiac ablation procedure? Is it the sickest of the sick or anyone with atrial fibrillation?
Dr. Bunch: Well, we've learned a lot just over this past year. A large trial came out that said, "When should we do it? Should we do it early?" And they took patients that developed atrial fibrillation within one year of diagnosis. We found that if we're going to get the most bang for your buck, the most efficacy for the procedure, we really should start looking at either using a medicine that helps the heart beat normal or an ablation within that first year. But that doesn't mean if you had atrial fibrillation longer that you wouldn't benefit from something like an ablation. Ablation is twice as effective as our medications.
And our patients that are the most sick really need their heart to be very efficient and those upper chambers to contract and squeeze just like the lower chambers. Sometimes they benefit from ablation as well and more so than medicines. And the best example of that is our patients with atrial fibrillation and heart failure. Ablation clearly is a better approach and actually can impact how long you live. If we can restore the rhythm effectively and get you off these medicines, it helps you live longer.
Interviewer: Now, one of the things I think we really need to talk about is that cardiac ablation is not necessarily a cure-all for AFib. Is that correct?
Dr. Bunch: Yeah, very much so. And it goes right back to that first thing I said regarding risk factors. If you still have risk factors that aren't treated at all, then our treatment approaches decrease in their efficacy and their success rates by as much as 50%. If you have sleep apnea that's untreated, then our success rates go down by 50%. So that's why when you see specialists, like myself, they will ask you about sleeping even though you came in with a heart problem. So you have to be diligent about the risk factors that you can control.
And then, also, atrial fibrillation, just like other chronic diseases, it can progress beyond the initial focal sources that we treat. And as it progresses, new areas can develop, and you could need a repeat ablation, or you could need a medication with the ablation to control it long term. But the good news with that is, if I am a patient that has atrial fibrillation, there's a lot I can do personally to help myself have a better outcome and to help the physician who is ultimately performing the procedure have a better outcome as well with the procedure.
Interviewer: For a patient that has been dealing with AFib for a while or maybe they just barely got their diagnosis, what advice would you give them for the treatment options available to treat their condition?
Dr. Bunch: Again, we need to work and minimize risk of stroke first. We're going to focus on that, and we're going to minimize risk of any potential injury or weakening to the heart. And then my approach has changed in the past year. I say, if we're going to do something about this rhythm, we should do it earlier, within the first year if possible, to keep the heart normal. The heart rhythm is a lot like kids. I have teenagers, and one teenager learns from the other. And the heart rhythm learns from the beat before it. So the more it's in fibrillation, the more it wants to be in atrial fibrillation. So we want to set the heart on a trajectory to want to beat normal. And so that's what we aggressively do in patients that have symptoms and want to pursue that route. People that don't have any symptoms at all, they said, "I came in for a test, and you found atrial fibrillation. I don't know why I'm here." In those people, we spend more of our time just making sure we lower stroke rates and making sure that that heart rate is well controlled, and so the muscle isn't in jeopardy of weakening.
