Melanie Cole, MS (Host): Welcome to AHN Med Talks, an informative resource for physicians across various specialties as we delve into the latest medical insights and best practices, ensuring you stay at the forefront of your field. I'm Melanie Cole. And today, we're talking about aortic disease, when to refer, when to transfer, and why center experience matters.

Joining me is Dr. Aryan Meknat. He's a cardiothoracic surgeon in the Department of Cardiothoracic Surgery at the Allegheny Health Network and an Assistant Professor at the Drexel University College of Medicine.

Dr. Meknat, thank you so much for joining us today. Can you start by describing a little bit about the current state of aortic surgery? Help us to understand the historical context and the current trends when we think of open repair versus endovascular approaches.

Aryan Meknat, MD: Well, thank you for having me. Aortic surgery like cardiac surgery continues to evolve. And what we've found in the past several decades is both with dissection, emergent intervention of aortic disease, along with aneurysmal elective intervention of aortic disease.

We've seen a significant improvement in early mortality, in outcomes, and what we're able to provide our patients, which is more durable repairs. And I think that comes with a mixture of both technological advancement with the type of grafts we've been able to place, where we place those grafts, but also with our technique, technique with respect to cerebral protection, with cardio protection along with having a true multidisciplinary approach to these diseases.

And when it comes to both cardiac and vascular surgeons working together alongside interventional radiologists to really manage these complex disease, I always say you have to have dynamic solutions for a dynamic pathology.

Melanie Cole, MS: Thank you so much, Dr. Meknat. So, speak a little bit about recognizing the patient that needs an aortic evaluation. Tell us about clinical presentations, risk factors, and imaging findings that should prompt surveillance or referral to an aortic specialist.

Aryan Meknat, MD: Well, aortic disease really in the grand scheme of things comes in two flavors. You have emergent dissection disease versus you have elective aneurysmal disease. And with the former, typically these patients will come into the emergency department hopefully sooner rather than later with either an extremis or with significant pain due to an underlying tear in their aorta.

And these are going to be best found on CAT scans. And once these are found, the best course of action is to really initiate impulse therapy for these patients. And what that entails is either a combination of medications, whether it be esmolol or calcium channel blocker in the form of a drip initiated very soon and then reaching out to these comprehensive centers, these larger centers where you can transfer them ASAP.

The latter, these aneurysmal disease of the aorta from the root all the way down to the bifurcation, really, these are most typically found incidentally. And what do we do with these when we find these? And typically, what we tell our network is we have pretty established guidelines of when to transfer these patients because the best place for these patients to be is under surveillance of a cardiologist and/or a cardiac surgeon or vascular surgeon.

And what we tell patients when they find an aneurysm anything greater than four centimeters to immediately reach out to either a cardiologist or a cardiac surgeon who can really determine and triage how often these patients should be surveilled. Because it's not just these static numbers we look at. Oftentimes, we'll look at the size of the aorta, but what is that relative to their height or their body surface area? We use more dynamic measures to determine their overall risk for potential rupture or dissection, which is why we even look at these aortas.

In terms of risk factors, family history is a big one. Patients with any sequela of some spectrum of connective tissue disease should raise or heighten our index of suspicion for underlying aortic disease, and we should have a low threshold to either scan these patients or even send them for something as simple as an echocardiogram to really evaluate their aorta and their chest.

Melanie Cole, MS: So along those lines then, Dr. Meknat, what information should accompany the patient when we think of the difference between expedited evaluation and emergency transfer versus that routine surveillance?

Aryan Meknat, MD: Well, with emergency transfer really once you have the CAT scan, it's really about getting their blood pressure and heart rate under control to facilitate their transfer to a center that can take care of them. In terms of the patients with incidentally encountered aneurysmal disease or those who might have been found because there was a higher index of suspicion, what needs to accompany them really is just the imaging findings.

And the cardiac and/or vascular surgical team will take it from there. And then, what that comes down to is really determining what else they might need and facilitating what they might need outside if we're setting them up for surgery, if that's what they need. If not, then it's simple surveillance that they're on.

What helps us determine if they need surgery outside is just these sizes is sometimes concomitant disease. So if they have other issues that need to be dealt with, sometimes our thresholds are lower to intervene on the aorta. My favorite conversations, though, quite frankly, to have with patients is once they have this aneurysmal aortic disease found, my favorite conversation is to say, "Hey, you don't need surgery. Let's continue surveillance," and to educate the patients and to try to alleviate some of the anxieties they might have in coming to the office and letting them know, "You know what? This is a disease we're going to keep a close eye on, but it's nothing that needs surgical intervention at this time." And those are, quite honestly, the best conversations to have.

Melanie Cole, MS: Now, tell us about your center, Dr. Meknat. Why program experience matters? What does your research show about the relationship between center experience and type A dissection outcomes and how standardized pathways, and we're going to talk more about this, the multidisciplinary collaboration can improve care and outcomes.

Aryan Meknat, MD: National data and our own data, we actually published a paper in the past two years looking internally within our network to see within all our cardiac surgical centers that are performing dissection surgery, what were our outcomes like? And what we did found very much mirrored national data to date, which is when you have centers that are performing more dissection surgery, more aneurysmal aortic surgery, their outcomes are inevitably going to be better.

And the reason that it is not only the technical prowess of the surgical team performing these procedures, but it's very much the perioperative care that these patients require. And that starts both preoperatively in their workup, intraoperatively with the assistance of cardiac anesthesiologists who are well-versed in how to take care of these patients, perfusionists running the heart and lung machine that are very comfortable with periods of circulatory arrest which are required for advanced aortic surgery.

And then lastly, and I think equally as important is the postoperative care. You know, having a center where these patients are monitored by intensivists in-house 24/7 who are very keyed in on what to look out for after big aortic surgeries like this.

And so, what we tell our partners both in-network and out-of-network is that what service we can provide these patients is high level of technical surgical care, but also perioperative care and a multidisciplinary approach, so that if they have issues that require our partners in vascular surgery or interventional radiology or interventional cardiology, we have them at our disposal 24/7 with advanced level of care that we can provide them.

And so, as I said before, complex diseases require a complex approach, a dynamic approach, and that's what these comprehensive aortic centers of excellence can provide.

Melanie Cole, MS: Doctor, when we think of open repair versus the endovascular approaches and all the technology that's happening so quickly in your field, I'm curious about the proficiency of open versus endovascular when you think of trainees. So when you're working with trainees, new vascular surgeons, are there any tips that you have when you're doing shared decision-making with your patients to think about which one is best or in an emergent situation, which one you have to use?

Aryan Meknat, MD: That's a great question because as we evolve, I think there i-inevitably is going to be a shift towards endovascular approaches, which I think in, in a lot of ways is, a fantastic option for patients to have both in the emergent and elective setting. But what I would say is I think having a multidisciplinary approach for all these diseases is extremely important because the cardiac surgical perspective versus the vascular surgical perspective can slightly differ.

But the conclusion we typically come to is what's going to be the best for this specific patient, both with what they can tolerate surgically, along with what are their own goals, own personal goals. And lastly, and probably most importantly, is what's going to be the most durable option for this patient?

So yes, ideally, in every patient, we'd like to perform an endovascular procedure that's going to be the least morbid option. But quite honestly, what we want to provide is not only improvement in survival, but improvement in quality of life and have a durable option so that if we need to do something open, do we set them up for something endovascular down the road so that we don't have to go back into that chest?

And similarly, with dissection surgery, in the emergent setting, the old dogma was get in and get out and have a life-saving surgery. And it very much still is in some ways. But as we move forward, as we evolve, in particular with these comprehensive aortic centers, our thinking is shifting. Our expectation is now survival, but how do we set this patient up for the future so that we don't have to reenter this chest and do a redo open big procedure? Can we set them up for a future endovascular procedure? Because our expectation is that hopefully, you know, not only do we have survival, but long-term survival as well.

Melanie Cole, MS: Tell us how treatment is evolving. Which patients may benefit from valve-preserving, hybrid, minimally invasive approaches? How are these technologies really changing care in your field?

Aryan Meknat, MD: It really comes down to the patient and their pathology. So to your point, if you're talking about down in the root, if they have aneurysmal disease of the root, you can't talk about the aortic root without talking about the aortic valve and vice versa. And so, it really comes down to, does this patient have a valve that's preservable? And if it is, we're going to do everything in our power to preserve that valve and reconstruct the root.

Similarly, if they have an arch disease or descending thoracic aortic disease, where that aneurysm lies, where that tear or dissection lies really matters. And what we look at is age, comorbidities, you know, cerebral protection strategies, cardioprotection strategies, whether they have concomitant cardiac disease. That helps us determine whether an endovascular approach is better versus an open approach. So for example, if they have an arch disease or a descending thoracic aortic disease in the very proximal portion, is this patient going to be better served with a total arch replacement and a frozen elephant trunk, or is the patient going to be better served with arch debranching, which doesn't require cardiopulmonary bypass, doesn't require a period of circulatory arrest, and we can debranch them and then subsequently place a TEVAR across their arch, the TEVAR being a stent graft within the aorta.

And it comes down to we keep using the same term, but it's so, I think, key and so important is durability. Similar to how we look at structural heart and cardiac surgery, I think we have to have the same perspective in the aortic space is durability. We can put a stent graft in someone who's younger, but how long is that going to last?

Is it going to maintain seal because that aorta is inevitably going to grow, or do we replace that diseased aorta completely with graft material that won't grow and then sets them up for a future endovascular option? So, I think that's why it's so important to have a multidisciplinary approach. It's important to have a comprehensive aortic center where there's extremely cordial relationship between cardiac and vascular surgery so that we can really analyze and look at these patients side by side.

I'm lucky enough, as are my partners, to share an office right across the way from our vascular surgery colleagues, so we're always coming into each other's rooms and talking about cases, and it's extremely cordial, and we all play well in the same box together.

Melanie Cole, MS: That's great to hear, and you made so many great points. As we wrap up, Dr. Meknat, what advice would you give to vascular surgeons as they're working with patients in that shared decision-making on open versus endovascular aortic disease surgical planning and some of the more important referral and transfer messages that you want other physicians to remember?

Aryan Meknat, MD: Well, specifically to vascular surgery colleagues of mine who are out there, I would say, work closely with the cardiac surgery team who are comfortable in the aortic space because I think perspectives are different, and I think working side by side to find the best procedural option for individual patients, I think is key.

For referral, I think it's really important to be not shy about referring these patients. I think it's important to get these patients surveil or on the pathway of surveillance sooner rather than later because quite honestly, we don't know what underlying genetic disorder this patient might have, what family history they might have, or what other atypical risk factors they might have for dissection.

We know that more than 60% of dissections happen less than 5.5 centimeters. And the national guidelines are to not intervene on aortas until they're 5.5 centimeters. So, I think it's important to get these patients referred sooner rather than later so they can be assessed and their own specific surgical risk can be analyzed, and then we can get them taken care of, or at the very least, get them on a surveillance pathway sooner rather than later.

Melanie Cole, MS: Thank you so much, Doctor. What a fascinating episode. Great discussion and such great information. Thank you so much for sharing your expertise with us today. And to learn more or to refer your patients, you can call 844-MD-REFER or visit findcare.ahn.org. Thank you so much for listening to this edition of AHN Med Talks with the Allegheny Health Network. I'm Melanie Cole.