Melanie Cole, MS (Host): Welcome to UF Health MedEd Cast with UF Health Shands Hospital. I'm Melanie Cole. And today, we're highlighting aortic dissections. Joining me is Dr. Eric Jeng. He's the Director of the UF Health Aortic Disease Center and an Associate Professor in the Division of Cardiovascular Surgery at the University of Florida.

Dr. Jeng, thank you so much for being with us today. Can you explain how the clinical presentation of aortic dissections differ between classic and tearing chest pain and more subtle or atypical symptoms, especially in women, as we're learning more and more about that, older adults and patients with connective tissue disorders?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: Thank you for having me, Melanie. Really appreciate being on with you guys. Dissection, sometimes they present in women a little bit differently, but they present with tearing back pain to the chest. One of the big things to differentiate is a DeBakey type I or type II dissection versus a type III dissection. Sometimes they're also classified as the Stanford A or Stanford B dissections. The Stanford A is a surgical emergency, and the DeBakey I or II, which is also Stanford A, is also a surgical emergency. And then, the DeBakey type III or Stanford B can be a surgical emergency, but it can also be managed medically.

Melanie Cole, MS: Thank you for explaining that to us. So from your clinical experience, what are some of the common pitfalls or delays in diagnosis that you see? How can the frontline clinicians reduce missed or late diagnoses of aortic dissection?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: You know, clinical suspicion is the key indicator. Everybody knows about strokes and everybody knows about having campaigns like FAST where you have them basically build all over the place and everybody knows, "Oh, let's look for stroke," but looking for dissections isn't as common Fifteen thousand aortic dissections happen in the United States alone and about almost half a million, so 400,000 worldwide each year. And so, the-these are real problems that cause real mortalities and having an index of suspicion is the key component. So, I mean, anytime anybody has chest pain, they start thinking heart attack or if you have some numbness on one side of your face or you can't move one side, you'd start thinking about a stroke. But patients, number one, and even providers don't always immediately think about a dissection happening.

Melanie Cole, MS: Before we get into guideline-based approach to managing Stanford type, I would like you to speak a little bit about what you feel is important for providers and indeed patients to notice. As you said, we've got Be Fast, we've got these campaigns, but what would you like them to know about not missing these things? You mentioned the tearing back pain in your chest. You've mentioned a few, but expand a little bit on that, what you directly look for.

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: By the time they find me, usually, they have the problem already. So, I don't see these people on the front line. Where I see these patients are in clinic when they have an ascending dissection, a known ascending aneurysm

Patients with ascending aneurysms, you know that that dissection is a possible sequelae of an ascending aneurysm. So, a dissection is just a tear of an aneurysm or even non-aneurysmal tissue, but it more often occurs when the tissue or the aorta is aneurysmal already. So, patients with a known history of aneurysms, patient with a known history of connective tissue disorders or known hypertensive problems where they present frequently with hypertensive issues, are on multiple medicines for high blood pressure, those are patients that, really, you should have a high index of suspicion for.

Melanie Cole, MS: Can you walk us through the current guideline-based approach to managing Stanford type A versus type B dissections and where in the real-world practice sometimes that has to diverge from the guidelines?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: Just to break it down from a standpoint of incidence, about two-thirds of patients present with a Stanford type A dissection, and that's that surgical emergency I was talking about before, where you have to have emergency heart surgery they usually talk about. And the Stanford type B is also a tear. It's just a tear in a different part of your aorta. Most of the time, a Stanford type B dissection can be managed medically, meaning impulse control. Impulse control means having your heart rate lower and then having your systolic blood pressure lower. Usually, the goals for heart rate are around 80 and a systolic blood pressure less than 120. That's called impulse control.

If there is no what we call end-organ malperfusion, that could be malperfusion to the legs, malperfusion to the guts, malperfusion to the kidneys. If there is end-organ malperfusion, even those Stanford Type B dissections have to be managed surgically. In those same cases, usually, a stent or an endovascular procedure is enough to fix that problem.

Type A dissection is that surgical emergency part. You have to go to surgery, otherwise half of those patients will die no matter what you do. A Stanford type A dissection means there's a tear in the aorta really close to your aortic valve or as close as your heart as it can get.

The reason why that's a surgical emergency is because the tear can propagate down to your coronary arteries. So, it goes down to the level of where the blood vessels feed your heart, and therefore kill you like that. They can cause what you call tamponade, which is blood around the heart, around the pericardial sac, and then make it so you have tamponade physiology and die that way, or cause malperfusion to not only the brain, but the rest of the body.

So, that's why a Stanford type A also categorized as a DeBakey type I or II, it becomes a surgical emergency where you have to go to the operating room and operate on those patients with a heart surgeon.

Melanie Cole, MS: Dr. Jeng, what are the major advances in open surgical repair for acute Type A dissection, such as cerebral protection strategies, arch replacement techniques, valve-sparing procedures? Tell us what's exciting in your field for that.

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: There are so many exciting things that have happened in aortic surgery in the last fifty years. We have so many different types of hybrid technologies. At the University of Florida, we're a part of every type of hybrid technology there is in clinical trials in development. And a lot of our patients have the option of being enrolled in those same trials. We have stents, inside stents, and then even what we call dissection stents or AMDS devices. We have specialized hybrid stent/gel weave grafts. There's so many of these different nuances to the care in aortic surgery that we provide at the University of Florida that makes it so much so exciting.

The reason for that really is because we happen to be the second busiest by surgical volume aortic center in the whole country. We do about a thousand aortic cases every year, and we're one of the few centers where our case mix index, which is how complex our patients are are among the top ten in the nation, our case volume is among top ten in the nation. And then, our mortality index, which is how well people do, is also top ten in the nation. So, not only do we do it at a high volume, we do it at high quality in very complex patients, and the patients survive.

Melanie Cole, MS: That is amazing to hear. So, how have endovascular and hybrid approaches, you just mentioned one, like TEVAR and frozen elephant trunk, changed that treatment landscape for complex arch and descending aortic dissections?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: Well, first and foremost, what that can provide is it provides a more comprehensive repair. So instead of simply replacing a segment of the aorta called the ascending aorta, maybe around 2 to 3 centimeters, we replace this large segment of the aorta that includes the entire arch. And what that does is it makes it so that there's lesser downstream surgeries you may need.

In many community hospitals, the surgeons aren't as used to doing aortic surgery. What happens is that if given no other option, they save the patient, and that's a great thing, and they replace the ascending aorta. But there are sequelae to that. Sometimes the aortic root gets bigger, and then you have to operate on that. Sometimes the aortic arch gets bigger, and you have to operate on that. Sometimes the descending aorta gets bigger, and you have to operate on that separately. So, one problem can mean three, four, five operations later if you don't get a very comprehensive solution from the jump.

Melanie Cole, MS: For patients with genetic syndromes such as Marfan, Loeys-Dietz, or those with bicuspid aortic valve, how has genetic testing do you feel, Dr. Jeng, and family screening changed your approach to prevention and timing of prophylactic surgeries?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: We actually have several genetics counselors that we utilize all the time. We send out genetic testings all the time. We provide, again, a lot of the genetics component counseling to our families all the time. Does it change for the patient?

Again, sometimes I meet these patients when they already have a dissection. So, not necessarily for the patient themselves, but a lot of times for their families. One time I met with a patient that I operated on with Marfan's. And the next clinic run, she brought about 20 family members in the clinic room with her. And each one of those patients eventually saw us. But this disease process travels in families, and understanding what everyone's relative risk is, is important. Because at the end of the day, with elective surgery, your outcomes are immensely better than if you have to have emergent surgery.

I'll give you an example. In a patient that's followed with an ascending aneurysm, I generally quote them a 1% mortality, a 1% stroke risk. We know in a patient that presents with an aortic dissection, at some of the best centers, at best, it's 15% mortality in-house. Our mortality in those same patients happen to be around 8% or less.

But again, that 8% or 10% is a lot more than one. So, treating these patients prophylactically when their aortas, when they're aneurysmal, they become a certain size, is very important. What that size is for patients with connective tissue disorders like Marfan's, Loeys-Dietz, is usually around 4.5 centimeters. In the regular population, it's around 5.5 centimeters. So, it's a centimeter less. So, you intervene a little earlier when you're dealing with those connective tissue problems.

Melanie Cole, MS: Dr. Jeng, and this is such an interesting discussion that we're having. And as you talk about the pure volume that you're doing there at UF Health, when you think of training residents and future surgeons, and so much of today is robotics and learning, do you feel that there's this gap? Because you were talking about open repair and in emergent situations. What would you like to say to residents and trainees about being able to switch at the last minute, go in and do that open repair, and planning for that, training for that so that there's not that gap

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: So I am also the program director for the Integrated Cardiovascular Surgery Program at the University of Florida. The integrated program is a surgical residency where we take residents that come directly out of medical school. These are the cream of the crop, basically. The residents that have the most research papers have the highest USMLE scores, do the best in amongst their medical school class. We are able to recruit these same medical students. And in our center, they flourish. So, I'll give you an example.

One of our fourth-year resident, me and him, we did emergent surgery on a mitrtal tricuspid yesterday. We did aortic surgery on a different patient the day before. these residents are getting to be trained out the gates. I am very confident that these same residents will be appropriately trained, not only to be certified, but independent aortic surgeons and complex cardiovascular surgeons when they graduate.

From a standpoint of robotic surgery, I think robotic surgery, there are certain avenues that I believe that robotic surgery is best applicable. I think in gynecology, it's super applicable because you're working inside the pelvis. Same with urology. Also in thoracic surgery, where you're doing lobectomies, lung-related surgery, I think you get a little bit less time in the hospital because of the pain scores and whatnot.

In cardiac surgery, I think robotics is a little bit different. There is no robotic application to aortic surgery. You can do minimally invasive or less invasive surgery with cardiac surgery. I think the robotic platform is probably best suited for mitral valve potential applications, sometimes aortic valve applications, and sometimes coronary applications.

So, robotic surgery is not probably the best platform for minimally invasive cardiac surgery. I think there are other approaches endovascularly that are better suited for aortic surgery as opposed to robot.

Melanie Cole, MS: Yeah, that's an interesting point that you made. So, how do you structure a multidisciplinary aortic program or aortic center of excellence? What impact does that specialized team you're discussing does that care have on outcomes compared with standard care?

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: It's super huge. I believe actually the multidisciplinary team—so, we have an aortic conference every other Tuesday, where the vascular surgeons ourselves and sometimes the cardiologist, and then also the interventional radiologist meet. We talk about all the cases that each one of our respective aortic surgeons sees, and then what they think about it. Sometimes, there's an open solution. Sometimes there's an endovascular solution to a complex problem. And sometimes there isn't a surgical solution, and we look to our interventional radiology colleagues for a plug or somehow to embolize something.

There are so many ways to tackle these problems. I think being in silos prevents a comprehensive solution for each patient. And the aortic center for us, what it does is it brings together all these specialties, and enhances the care for the patient because it breaks down these silos. And because of that, I think the patients get optimal care, the best care they can in the nation.

Melanie Cole, MS: And looking ahead 10, 15 years, how do you envision the care pathway for patients at risk or living with aortic disease changing, particularly with advances in genetics, endovascular technology, AI-driven prediction models? What do you see happening? What do you hope will happen? And please offer your best advice and final thoughts.

Eric Jeng, MD, MBA, FACS, FACS, FACC, FCCP: The AI part is exceptionally huge for us. And the reason for that is we know that computing power is more than any human can do, the artificial intelligence computing power. Especially with, all the resources we have, including the HiPerGator at the University of Florida, we've been able to leverage all of these resources, and we've created AI models, especially for our sepsis prediction in our cardiovascular unit. Aortic surgery and cardiovascular surgery inherently go hand in hand. Sometimes it's complex cardiovascular surgery that includes the aorta. Sometimes it's aortic surgery that includes the heart. And so, these go hand in hand for us.

I think with a center like ours, where we have very little silos, we have all of these subgroups working together hand in hand, in addition to having prediction models, not just of sepsis, but also aneurysmal growth, and having all of the capabilities, either endovascular, open, hybrid technologies, to utilize all these approaches in combination, you really get what I like to call a precision model of medicine that is important for every patient. That way, you get a customized approach to what you . As opposed to a blanket one type of solution for every problem, you get a very customized solution for the patient. And I think that is what will be different going forward. Everybody will get a customized approach to what they need. I think an individualized precision model medicine is the key to the future. And utilizing AI to help with that.

And AI, sometimes we believe that, you know, AI is the solution to everything, and everybody's probably put in something in ChatGPT and realized it's wrong. So, there is the human component that really standardizes everything and the checks and balances between that and ensuring that we're not just believing whatever's input. That these models where real surgeons, expert clinicians take into account the real-world changes and how that affects the modeling of this and adapting to the different changes that you're seeing is going to be key.

Melanie Cole, MS: Well, it certainly is very exciting time. Thank you so much, Dr. Jeng, for joining us today. And to learn more about this and other healthcare topics at UF Health Shands Hospital, please visit innovation.ufhealth.org. And to listen to more podcasts from our experts, you can always visit ufhealth.org/medmatters. That concludes today's episode of UF Health MedEd Cast with UF Health Shands Hospital. I'm Melanie Cole.