Transcription:
An Alternative Treatment for Heart Rhythm Disorders: Convergent

Prakash Chandran: Welcome back to HeartSpeak, the podcast from Baylor Scott & White Heart and Vascular Hospital. I'm your host, Prakash Chandran. According to the Heart Rhythm Society, there are roughly 2.3 million people living with atrial fibrillation. And heart rhythm disorders in general are fairly common.

On our HeartSpeak podcast, we've addressed AFib and ablation for heart rhythm disorders among some of our topics. And today, we'll be discussing a fairly new treatment option approach for heart rhythm disorders called a convergent procedure. This procedure is a collaborative effort between a cardiac surgeon and an electrophysiologist, and we'll be learning more about it today with Dr. Dan Enter. He's a cardiothoracic surgeon on the medical staff of Baylor University Medical Center and Baylor Scott & White Heart and Vascular Hospital Dallas.

Dr. Enter, really great to have you here today. You know, before we talk about a convergent procedure, I just wanted to start with the basics. What exactly is atrial fibrillation or AFib?

Dr. Dan Enter: Yeah, Prakash. Thank you for having me on the show. I really appreciate it. Atrial fib also called atrial fibrillation or AF is a quivering or irregular heartbeat; in medical terms, an arrhythmia, that can lead to blood clots, stroke, heart failure, and other heart-related complications. And as you already mentioned, at least two and a half million Americans are living with AFib.

Normally, your heart contracts and relaxes in a regular beat. In AFib, the upper chambers of the heart called the atria beat irregularly. You could think of it as quiver instead of beating effectively to move blood through the ventricles. And if a clot breaks off and enters the bloodstream, it can lodge an artery leading to the brain, which can result in a stroke. And in fact, about 15 to 20% of people who have strokes ended up having atrial fibrillation that they may not have been aware of. And so this risk of a clot is why many patients with atrial fib are put on blood thinners. Untreated atrial fib doubles the risk of heart-related death and is associated with a five-fold increase in stroke.

Prakash Chandran: So, thank you so much for the definition. I'm trying to understand people with AFib, what symptoms do they experience? You know, you kind of talked about an irregular potential heartbeat. Do they experience like fluttering or pain in the chest? Maybe talk about some of those symptoms.

Dr. Dan Enter: Yep. There's a wide variety of symptoms. And they can include feeling not well overall. But one by one, they are general fatigue, rapid and irregular heartbeat, fluttering or thumping in the chest, dizziness, shortness of breath and anxiety, weakness, faintness or confusion, fatigue when exercising and sweating. And so, although having an attack of atrial fibrillation can be odd and frightening, it usually doesn't have harmful consequences in itself. It's really that risk for stasis in the upper chamber of the heart and ultimately stroke. And so that's why it's important that people seek treatment and potentially get put on blood thinners if they do have atrial fib.

Prakash Chandran: So let's talk about how one actually gets a AFib diagnosed. You know, if they're, you know, experiencing some of the symptoms that you just talked about, is this something that they, you know, identify on their Apple Watch? I know the apple watch now can track some of this stuff. Or do they go in to see their doctor? Maybe talk a little bit about that initial diagnosis.

Dr. Dan Enter: Yeah, it's fairly easy to diagnose. It's done by electrocardiogram, which looks at the electrical activity of your heart through a couple of small monitors placed on your chest. And so that can be done in a primary care physician's office. And typically, they would refer you to a cardiologist and we can talk about treatment later in the podcast. But in addition, an Apple Watch, if it can't already do that, it will be able to in a year or two. It's fairly easy to diagnose.

Prakash Chandran: Understood. And before we get into the treatment, are you able to talk about some of the risk factors that lead to AFib?

Dr. Dan Enter: Sure. Yeah. So who is at higher risk? Essentially, people of advanced age. So people in their 60s, 70s, 80s, high proportion of them do have atrial fib, greater than 15%, 20% in some age groups. People with high blood pressure. In particular, people with underlying heart disease with valve issues, hypertrophic cardiomyopathy, people who've had heart attacks, people who've had heart surgery. Actually, typically after heart surgery, one-third of people have atrial fibrillation.

But in fact, it's well-treated because we're doing EKGs on our patients daily. And so we see it, pick it up, put them on blood thinners. And in fact, this could be the topic of another podcast. But after coronary surgery in particular, a recent randomized trial showed that clipping off the appendage reduces strokes by a third, after all coronary surgeries. And clipping off the appendage is something that we do in the convergent procedure also. But to get back to who's at higher risk, heavy alcohol drinkers, people with a family history of AFib; people with sleep apnea, it's not proven, but we've shown a strong link between sleep apnea and atrial fib, and then other chronic conditions including hyperthyroidism, diabetes, asthma among others.

Prakash Chandran: Okay. So let's move on to treatment options. What has been the traditional or conventional treatment option when AFib is initially diagnosed?

Dr. Dan Enter: Yep. So there's things that can be done on the patient side and then there's things that physicians do. So, our overall goals are to restore the heart to a normal rhythm and that's called rhythm control. Another way to look at treating AFib is reducing overly high heart rate and that's called rate control. We want to prevent blood clots, that's what blood thinners are used for. Manage the risk factors for stroke and then prevent additional heart rhythm issues and heart failure.

So what a patient can do to reduce their risk of complications are to get regular physical activity; eat a heart-healthy diet, low in salt, saturated fats, trans fats, and cholesterol. Manage high blood pressure. Avoid excessive amounts of alcohol and caffeine. Avoid smoking. Look at their cholesterol and also maintain a healthy weight.

On the physician side, we typically use medications such as beta-blockers and calcium channel blockers, which work on part of the electrical system of the heart. And they may slow the heart rate and help improve symptoms.

Prakash Chandran: Okay, great. And I've also heard of a procedure called ablation. Is that also a treatment option?

Dr. Dan Enter: Yep. There's a couple things people typically get. Many patients who come with atrial fib initially get back and well-controlled with medications. If those aren't working as well, they may undergo a cardioversion, which is a procedure in which they have some mild anesthesia and receive an electrical shock, which can reset the heart to a normal rhythm.

And so, you know, that's usually a first step and then subsequent to that, ablation can be performed. And so that's done by a cardiologist who has a specialty in electrophysiology. And so a catheter, which is a thin flexible tube is inserted to the patient's blood vessel through the groin and is gently guided to the heart. And that physician then carefully applies energy to the malfunctioning tissue that they identify on the inside of the heart. And there's a couple of different ways to do that, to produce scar in the problematic areas so that they are no longer sending the abnormal electrical signals. And if this is successful, the heart returns to a normal rhythm.

Prakash Chandran: So we're talking today about this convergent procedure. And as you mentioned, this is something that is typically for patients with long-term AFib. Talk a little bit about what the procedure is and who it is ideally for.

Dr. Dan Enter: Yeah. This is a procedure I really enjoy doing. I do the full spectrum adult cardiac surgery. So heart transplant, artificial heart, bypass surgery, valve surgery, most of that I do minimally invasive, and also aortic surgery, which is the biggest blood vessel coming off the heart. But I think my favorite out of all these is the minimally invasive procedures because really the patients do so well. They go home in a couple of days and, you know, pending a good result, everyone's happy. the convergent procedure is really one of those.

So most of these on Mondays. The patients go home typically Wednesday, maybe Thursday. And who is a candidate for this procedure? Someone who has had long-standing atrial fib. So not for three or six months, but more for a year or two years. And I would say typically they've had an ablation procedure in the past, maybe two of them. And ultimately, they're still in symptomatic atrial fib. So they're not feeling well. They go to their doctor, they're still in atrial fib. And let's say they get a cardioversion, the electrical procedure we talked about, it doesn't put them back into normal sinus rhythm. So some of those patients have an understanding, 'Well, I'm just going to be in AFib forever," but actually there's more that we can do.

the convergent is a minimally invasive procedure. We make a few small incisions. We apply energy to the back wall of the heart and we can achieve an ablation that's actually fairly large in area in a different area compared to what can be done endocardially through the ablation procedure we discussed.. In addition, we clip off the left atrial appendage where 80% to 90% of blood clots form that can become strokes. So we're taking away the main modality in which stroke can happen.

the one reason I got into this is that there was a major randomized study looking at over 150 patients showing convergent procedure versus conventional treatment. And when we look 18 months later, 74% of convergent patients had a 90% reduction in atrial fib compared to 55% of patients in the conventional treatment group, so that's an endocardial catheter ablation. And this is the most clinically relevant outcome, you know, is 90% of the AFib gone. then we can get into other parts of, well, are we comfortable taking the patient off blood thinners and taking them off the antiarrhythmic medications? Because these medications can have very serious side effects for some of our elderly patients.

Prakash Chandran: You know, I'd love to learn a little bit more about the dynamics of how the convergent procedure works. You know, you talked about it being minimally invasive, faster recovery time. But maybe talk through how you first identify that a patient might be a good candidate for it and then what the procedure ends up looking like at a high level.

Dr. Dan Enter: Yeah, this is what I really enjoy about being a part of different areas of medicine. So in valve disease, aortic valve disease, mitral valve disease, it used to be entirely surgical. And now, it's moved toward, certainly in aortic valve disease, mostly interventional. what I mean by that is that in these changing of the treatment paradigms, we evaluate the patient, but with both medical and surgical doctors and other specialists and identify the plan that's best for them.

in valve surgery, for example, we do this through a valve. We meet and discuss every patient in a multidisciplinary fashion. And then we'd go out and talk to the patient together. And if they have any questions from either side, we can answer them. And that's a lot better than the patient going to one specialist, going to another specialist, hearing a different answer, not quite having a clear picture of, one, what is going on with them, two, what is the best next step?

what we've done with atrial fib is develop a rhythm center. then a patient can come in. Let's say they've had AFib for two years. They've had an ablation. They're very symptomatic. They're on medications that make them feel poorly. And let's say they had a fall and then they had bleeding and they're concerned about being on a blood thinner. So we can review all those patients studies and imaging and let them know if they're a candidate for either the convergent procedure, a different type of conventional ablation. A cardioversion would help, a medication change and see what medical or surgical strategy would be best for them. And so that's why we developed a rhythm center to help every patient evaluate and get a full answer on the day of their visit.

Prakash Chandran: Yeah, that's pretty awesome and a comprehensive way to really look at all of the options and narrow in on what is best for the patient. You know, you talked a little bit about managing that left atrial appendage during a convergent procedure. Is that something you want to speak to at a high level here?

Dr. Dan Enter: Yeah. Basically, we think that that prevents at least one-third of strokes from atrial fibrillation. I do that through two small scopes from the left side of the chest. And what's nice in particular about that is that the clip is on the outside of the heart. So that means from the perspective of the inside of the heart, it's just regular heart tissue to regular heart tissue. So the patient doesn't need additional anticoagulation past that, and that can be a big deal for some of these patients. They've had blood thinners, but they have atrial fibrillation and they're really worried about having a stroke, because they can't take blood thinners. when we clip off the appendage then, we believe their risk of stroke is significantly lower. And so that even by itself as an isolated procedure outside of a rhythm portion of the conversion procedure offers significant benefit.

Prakash Chandran: Awesome. So Dr. Enter, thank you so much for your time today. This has been super informative. Is there anything else that you'd like to leave our audience with regarding heart rhythm disorders, AFib or the convergent procedure?

Dr. Dan Enter: No, Prakash. Thank you. I really appreciate it. Just that if someone has complex and difficult to treat AFib, you know, we're happy to evaluate them and see if there's something that we can do.

Prakash Chandran: Awesome. Well, thank you so much again. That's Dr. Dan Enter, cardiothoracic surgeon on the medical staff of Baylor Scott & White Heart and Vascular Hospital Dallas and Baylor University Medical center.

Thanks for checking out this episode of HeartSpeak. To find a specialist on the medical staff at Baylor Scott & White Heart and Vascular Hospital in Dallas or Fort Worth, please visit bswhealth.com/dfwdoctors, or call (844) 279-3627. For more information about the convergent procedure, please contact the Heart Rhythm center in Dallas at (214) 820-5306. If you found this podcast helpful, please share it on your social channels and be sure to check out the entire podcast library for topics of interest to you.

My name is Prakash Chandran. Thank you so much, and we'll talk next time.

Host: Baylor Scott and white heart and vascular hospital, Dallas and Fort worth joint ownership with physicians.