Treating Atrial Fibrillation (AFib) with Cryoablation

Intro: This is Weekly Dose of Wellness, brought to you by MemorialCare Health System. Here's Deborah Howell.

Deborah Howell (Host): Welcome to the show. This is your Weekly Dose of Wellness. I'm Deborah Howell, and today's guest is Dr. Paul Drury. Dr. Drury is board certified in internal medicine, cardiovascular disease, and nuclear medicine and has advanced training in echocardiography. He's currently a cardiologist at Saddleback Memorial Medical Center. Dr. Drury is here to talk to us today about AFib. It's the most common type of arrhythmia or heart rhythm disorder. The incidence of AFib increases with age, affecting one in ten people and can lead to stroke or other cardiac complications if not treated. We'll be talking about the causes, symptoms, and risks of AFib as well as some treatment options, including cryoablation. Welcome, Dr. Drury.

Paul Drury, MD: Good morning.

Deborah Howell (Host): Glad to have you. What is atrial fibrillation or AFib?

Paul Drury, MD: So atrial fibrillation is, as you mentioned, the most common heart rhythm disorder. It's a condition where the top part of your heart, which is the atrium, instead of beating in a regular fashion, beats very fast and very irregularly. It can be associated with a very fast heart rate that you feel or sometimes just an irregular heart rate that you feel. But it's just disorganized, irregular heart rate is the easiest way to describe it.

Deborah Howell (Host): Got it. What are the causes of AFib?

Paul Drury, MD: Atrial fibrillation is multi-uh factorial. I think the most common time we see it is in people who are at an older age. We mentioned that over the age of seventy, over age of the eighty, almost one one in four to five people can be found to have atrial fibrillation. Other significant causes are any type of heart disease, from having long standing high blood pressure to having a heart attack or congestive heart failure. It's also commonly seen if you have a heart surgery or can be caused just by stress. There are a few patients, especially younger patients, who have a genetic predisposition to atrial fibrillation. However, the exact genes and latest screen for that hasn't been discovered yet.

Deborah Howell (Host): Understood. What symptoms might patients experience if they have AFib?

Paul Drury, MD: Most commonly the symptoms are from feeling a rapid heart rate. Sometimes it'll just be feeling an irregular heart rate, and there are patients who have no symptoms at all. But if the patient feels an unexplained racing of their heart, especially if it just feels a little bit off. It doesn't feel like a regular when you're exercising type of rapid heart rate. That's that's normally what people will feel.

Deborah Howell (Host): Okay, and they're just sitting there or they're not doing much.

Paul Drury, MD: Right, sitting there, not exercising, all of a sudden the heart's going at a hundred and fifty, hundred and sixty beats per minute and that's that's often what people will feel.

Deborah Howell (Host): And how would you feel that? What's the sensation of that?

Paul Drury, MD: Often people will feel maybe a little bit of dizziness, a little bit of trouble breathing, a little chest pain. Sometimes those symptoms aren't present, but those are the most common ones. And then oftentimes it'll just be you can't do what you used to if you're in atrial fibrillation. Some people have symptoms of just feeling tired and just not being able to do what they normally were used to doing.

Deborah Howell (Host): It's gotta be a little scarier, at least unsettling.

Paul Drury, MD: It's very, very unsettling. Especially if it happens at rest and the heart rate's going really fast. It feels like you're exercising even though you're not, and it often prompts patients for their first episode to seek medical care in the emergency room to figure out what's going on.

Deborah Howell (Host): Okay. Now if not treated, what is the risk factor for stroke and heart failure?

Paul Drury, MD: So stroke is the big one. A lot of people have atrial fibrillation, especially older people that stay in atrial fibrillation for years and do just fine as long as they're on the right medications and mainly to prevent stroke. So stroke risk varies a lot by risk factors. Someone who has atrial fibrillation who is young, who's healthy, who has no other heart conditions, high blood pressure or diabetes, their risk of stroke is very low, almost what the normal population is less than one percent. As you start adding chronic medical conditions such as high blood pressure, diabetes, congestive heart failure, age above seventy-five, or previous heart attacks or even strokes, those risk factors start adding up and the risk per stroke builds up to the point where if you have all of those that I mentioned, almost about fifteen percent per year risk of stroke, which is incredibly high.

Deborah Howell (Host): Yeah, that is very, very high. So what are some of the treatment options for AFib?

Paul Drury, MD: So number one, if you're on have atrial fibrillation you need to see a cardiologist to once again go over the risk factors and come up with a treatment plan. Further treatment typically depends on symptoms. So when I always when I see someone with atrial fibrillation, first they always go over their stroke risk and we decide on whether they need to be on no blood thinners. If they're very, very low risk consider just aspirin. And if they have higher risks, consider a more potent blood thinner such as Pumidin, or now the novel anticoagulants which include Zeralto, Eloquis, and Pradaxa. Once we assess the stroke risk and come up with a treatment plan, we decide what we do about the actual rhythm. There are a couple ways to treat it. For someone who is very mildly symptomatic or minimally symptomatic, often we'll try medications first and that can be done to either control heart rate or to try and maintain them in a normal heart rhythm. And those can be done with multiple medications. If someone is highly symptomatic from their atrial fibrillation then there are two plans of action. One of them is to try medications first to try and keep that heart rate out of atrial fibrillation. There are many medications available but often there are side effects to those medicines, but if you try the right combination it will work. The other option is ablation for atrial fibrillation.

Deborah Howell (Host): Okay. Let's get into that.

Paul Drury, MD: Ablation can be done in a couple ways. It is where we take catheters, which are small tubes that we can insert through the veins or large blood vessels in the leg and and bring them up to the heart. Once we get up there we're able to find the heart tissue that causes the atrial fibrillation and then either burn it or freeze it to get rid of the triggers for the atrial fibrillation and help maintain normal heart rhythm.

Deborah Howell (Host): So you're really deadening that tissue so it can't receive those signals?

Paul Drury, MD: Exactly. So atrial fibrillation, just to get in a little bit more detail, is typically caused by a large set of veins. And these veins bring the blood from the lungs back into the heart. And we have discovered that these pulmonary veins typically drive the atrial fibrillation and cause the atrial fibrillation to start. So what we're trying to do is disconnect these veins from the heart electrically.

Deborah Howell (Host): Yes.

Paul Drury, MD: There's still blood flowing through them. There's just no way for electrical signals to go from the vein into the heart. Kind of like clipping wires is kind of a way to describe it.

Deborah Howell (Host): Is it similar to when people have the nerve on their neck burned so they can't feel that pain through their spine?

Paul Drury, MD: Yeah, similar. Similar to that.

Deborah Howell (Host): Okay.

Paul Drury, MD: And it's not specifically nerves, it's all your heart muscles and have electrical conduction properties, but they all function like nerves. And so what we do is want to disconnect those so those nerves and those signals cannot escape those veins. And when this procedure was first started approximately fifteen years ago, it was always done by burning. You'd have to go in a circle, very slow, almost like spot welding on the just outside of these veins to get those signals to go away and clip those nerves. Very long, tedious process. Now we have a mechanism called cryoablation and we use something called a cryoballoon, which is a balloon that we can inflate right inside that vein. And then instead of burning, it freezes. And it freezes a big circle. And that big circle is able to take out all those nerves and clip all those wires in a circular fashion in one shot. It's a much faster, more efficient process.

Deborah Howell (Host): Incredible, I love it. And what are the benefits of cryoablation?

Paul Drury, MD: So the main benefit is freedom and treatment of atrial fibrillation. It's not a perfect procedure but it's getting better. We're up to about for the right patient, about eighty percent long term success rate for not having return of the air to their atrial fibrillation. That's pretty good, an eight out of ten chance of staying out of the atrial fibrillation without taking specific medications to control it.

Deborah Howell (Host): Absolutely. Just getting off the medications itself is a huge victory.

Paul Drury, MD: That is the main goal.

Deborah Howell (Host): Well, thank you so much, Dr. Drury. I have many more questions, but sadly we're out of time. So please, can you come back and talk to us more about cryoablation?

Paul Drury, MD: Absolutely, be very happy to.

Deborah Howell (Host): Fantastic. To learn more or to listen to a podcast of the show, please visit memorialcare.org. I'm Deborah Howell. Join us again next time as we explore another Weekly Dose of Wellness. Have yourself a fantastic day.