Melanie Cole, MS (Host): Welcome to UAB MedCast. I'm Melanie Cole, and today we're delving into the clinical practice guidelines on surgical treatment for atrial fibrillation with Dr. Panayotis Vardas. He's a Cardiac Surgeon and Associate Professor at UAB Medicine. Dr. Vardas, it's always a pleasure to have you join us on the show.

I'd like you to start by outlining the key aspects of past clinical practice guidelines for surgical treatment of atrial fibrillation for us.

Panayotis Vardas, MD: Melanie, thank you again for having me here. It's always a pleasure. So as we know, atrial fibrillation is a substantial public health concern, with increasing incidence and prevalence in the general population. Actually projections expect fibrillation patients to double between 2010 and 2060.

So as you know, this is really major public health concern, not just individual patient problem. It is particularly common among patients with other cardiovascular pathologies, especially those patients that they have valvular heart disease. In fact, there are studies that from 30 to 50 percent of patients undergoing surgical or even transcatheter aortic valve replacement present with atrial fibrillation.

And this is associated with worse prognosis after valve replacement, including worse procedural outcomes, bleeding events, mortality at two years. There was a recent review of the Society of Thoracic Surgeons Adult Cardiac Surgery Database and it was found that the adaption of surgical ablation and surgical left atrial appendage occlusion has not changed substantially in the last five years, although there's strong recommendations from the 2017 Society of Thoracic Surgeons guidelines.

Again, this demonstrated that there is substantial room for changes in cardiac surgery practice to align more with what is the current scientific evidence. In 2022, only 43 percent of all patients with documented atrial fibrillation undergoing first time cardiac surgery, which is not emergent, were treated with surgical ablation plus left atrial appendage occlusion.

Thirty percent of this patient population received neither surgical ablation nor any left atrial appendage management. This was the background of what happened between the 2017 and 2023 guidelines. In 2017, the SDS published a comprehensive clinical practice guideline review for surgical treatment of patients with atrial fibrillation.

And that document summarized the relevant literature at that time, the outcomes, the results, and provided recommendations for the clinical practice. As you know, clinical practice guidelines are due for an update every five years to ensure that the guidelines reflect the current body of literature and the most current evidence. That was the background before the 2023 update.

Host: Dr. Vardas, thank you for that. That was a comprehensive answer and you specialize in valve reconstructive surgery, as you were just speaking about, and arrhythmia, and you're actively engaged in cardiac surgery research. So you co-authored the article, The Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Management of AFib, in the annals of thoracic surgery. So Dr. Vardas, tell us about these new guidelines, compare and contrast for us. Why should more surgeons and cardiologists be more informed on this topic?

Panayotis Vardas, MD: Absolutely. Thank you, Melanie, for this question, because it's really a very important question. The Society of Thoracic Surgeons Workforce on Evidence Based Surgery assembled a writing group in 2022 to review the current literature and how it has changed. And we focused on randomized controlled trials, meta analysis, registries, observation, and descriptive studies.

After the review of all the new data was done, there was a confidential voting and the consensus document was produced. So, nonemergency cardiac operations in patients with atrial fibrillation should include surgical left atrial appendage occlusion during the operation. And the guidelines reinforce the long term benefits of surgical ablation of AFib during those operations.

It is important that every patient with atrial fibrillation undergoing elective open heart surgery, have their atrial fibrillation treated and their left atrial appendage managed. And this is a wake up call for the surgical community. In fact, in 2017 was given the highest level of recommendation, Class 1, to surgical ablation for patients with atrial fibrillation undergoing first time non emergent operation of the mitral valve due to the safety and long term benefits. The 2017 guidelines gave a Class 1 recommendation for surgical ablation during concomitant aortic valve and coronary artery bypass operations. However, the 2023 guidelines extend this Class 1 indication to all first time non emergency heart surgery. That means, for example, aortic surgeries, surgeries for intracardiac defects like ASD closures.

All these patients should be treated. That's one big difference. The second one, because of new evidence and randomized trials. In 2017 guidelines, the left atrial appendix exclusion or excision in conjunction with surgical ablation was deemed reasonable, was given a class 2A recommendation. Instead, the 2023 guidelines upgraded this to a Class 1, and this is very important because if you have a patient with atrial fibrillation, whether or not you perform a surgical ablation and the patient undergoing first time, not emergent cardiac surgery, at least as a surgeon, close the left atrial appendage.

This is a very strong message to the surgical community, given the outcomes from these randomized trials, with a decreasing of the risk of stroke, and, the other sequelae that can happen in the setting of set of atrial fibrillation. The 2023 guidelines also add a class 2B recommendation for consideration of isolated surgical appendage obliteration in patients with longstanding persistent atrial fibrillation at high stroke risk in whom long term oral anticoagulation is contraindicated or has failed.

And there are several techniques you can accomplish that. The message about the left atrial appendage occlusion is so strong that currently there are large multi center industry sponsored clinical trial trying to address the issue in the setting of not atrial fibrillation. So whether or not it's a good idea or not to close the left appendage on all patients undergoing cardiac surgery, period.

And those outcomes will come out and they will evaluate this by 2032.

Host: So you don't have those outcomes just yet for us.

Panayotis Vardas, MD: We don't have this is again for patients that they don't have atrial fibrillation. We want to see whether or not the left atrial appendage occlusion is a good idea, which is essentially going to change the entire idea of how we perform cardiac surgery for all patients.

Host: Dr. Vardas, what do you expect if you were to look into the future? Because this study sets that new standard of care that's pretty significant across the United States, expected to influence how cardiac surgeons manage their patients. What do you expect to happen?

Panayotis Vardas, MD: It's hard really to anticipate those outcomes. What we know is if you address the left atrial appendage with a surgical clip, for example, you might have increased post operative atrial fibrillation incidence, but the long term outcomes in terms of stroke prevention, might be so significant that actually, might be a good idea to be implemented in all cardiac surgeries.

Melanie, the other thing I would like to underline about the 2023 guideline is the first time that actually was introduced in the guidelines, the idea, as a level 2A recommendation; when a patient is being evaluated for surgical valve repair or replacement in the setting of atrial fibrillation, it's recommended to undergo surgery, rather than trascatheter valve repair or replacement, for example, TAVR, if the patient undergoes surgery with concomitant surgical ablation and left atrial ablation occlusion, and that's a level 2A recommendation. And this is also very important in the current era with the huge change in practice that we have in the last 10 years with the introduction of the transcatheter valve therapies.

So it's something is new in the 2023 recommendations.

Host: That's a lot Dr. Vardas. These are so significant and important and I'd like you to just expand a little bit on the non emergent cardiac surgery patients with AFib and surgical ablation and how you are recommending this. You touched on it earlier, but speak about why this is significant as well.

Panayotis Vardas, MD: It's significant because atrial fibrillation is essentially what is often thought as the cancer of the heart. It can give cardiomyopathy, can give clotting within the heart that can give further thromboembolism and strokes. So it's important to address, restore to sinus rhythm and prevent this with surgical ablation.

And there are several techniques we can do that. Technology has advanced. Even for operations that we don't have to open the heart, to do open, essentially open intracardiac surgery, there are still techniques we can apply to do surgical ablation. For example, the posterior wall of the left atrium, the box lesions, as is well known, and close the appendage, address the appendage.

But the standard of care for all these operations is what we call, surgical ablation or Cox-maze III or IV procedure, where essentially what you do is you ablate specific pathways that you interrupt those circuits of atrial fibrillation to happen in addition to occlude and obliterate the left atrial appendage.

Host: Dr. Vardas, how do you envision surgical treatment and these changes for AF integrating with all these other specialties and treatment modalities. You've mentioned quite a few here today in this multidisciplinary and interdisciplinary approach. How do you envision that this is all coming together? Because it's very exciting time in your field.

Panayotis Vardas, MD: Thank you for bringing this up, Melanie, because this is addressed from 2023 guidelines and actually reiterate the value of multidisciplinary heart team assessment, treatment planning, and follow up of rhythm assessment for optimizing patient outcomes from multidisciplinary heart team, which include;

cardiologists, structural cardiologists, electrophysiologists, and cardiac surgeons. And when we make decisions like this, especially with the last recommendation I mentioned, the 2B recommendation for patients that do have atrial fibrillation and valve problem and they are low or intermediate risk, which can push us more towards surgery versus transcatheter approach is again a shared decision between the patient and the heart team.

Host: As we wrap up and what an enlightening eye opening discussion that we're having here today. You're such an interesting man and you have so much information to share. What are some final thoughts, key takeaways for other providers that you would like them to know about the importance of this article in the Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Treatment of AFib?

Panayotis Vardas, MD: I would like to see that all providers and especially cardiac surgeons would pay more attention to atrial fibrillation. We'd like to see more adoption of surgical ablation for patients that do have atrial fibrillation. And again, the message that comes out from this document and I would like to reiterate is at least, if we don't do an ablation, at least close the left atrial appendage. The patient will have benefit at least from that. However, doing an ablation, it's something we should all evaluate for patients that do come for surgery with atrial fibrillation. The other thing I would like to see is the heart teams, they take more into consideration the atrial fibrillation when we make decisions for low or intermediate risk patients to undergo transcatheter versus surgical approach of the structural heart problem to make consideration of the atrial fibrillation because we do have more tools with surgery to address this problem.

Host: Thank you so much. As always, Dr. Vardas, what a great guest you are. Thank you so much for joining us today. And for more information, please visit our website at uabmedicine.org/physician. That concludes this episode of UAB MedCast. I'm Melanie Cole. Thanks so very much for joining us today.