Rania Habib, MD (Host): Mitral valve disease is the most common form of heart valve disease in the US. And it is estimated that this diagnosis contributes to at least half a million hospital admissions each year.

Welcome to AHN MedTalks, 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 your host, Dr. Rania Habib.

Joining me today is Dr. Walter McGregor, the Director of Cardiac Surgery at Allegheny Health Network. He is here to discuss the power of early referral to a cardiac surgeon in the management of mitral valve disease. Welcome, Dr. McGregor. We are honored to have you on the podcast today.

Walter McGregor, MD: Dr. Habib, it's my pleasure and excited to chat about an area of cardiac surgery that's a passion of mine and something that we have fair amount of expertise with at Allegheny Health Network, and looking forward to share some of that to our physician community.

Host: We are so excited. Mitral valve disease encompasses several main diseases. Could you describe the main types?

Walter McGregor, MD: Sure. I think, oftentimes, we break mitral valve disease down into rheumatic fever inducing mitral valve disease, and then anything that's not rheumatic fever. And certainly around the world, rheumatic heart disease is probably the most prominent form especially in non-first world countries that just don't have the same access to healthcare. But in first world countries, non-rheumatic mitral valve disease really is the most prominent. And most of the time, we're talking about what we call a degenerative disease or floppy valve disease. Certainly, mitral valve disease can relate to other disease states as well. Sometimes people with heart failure have mitral valve leakage or people with atrial fibrillation have mitral valve leakage. But oftentimes, the mitral valve disease is secondary to those diseases. So, worldwide at least in developed countries, degenerative or floppy valve diseases is the area of mitral pathology that we really focus on the most from a surgical perspective.

Host: Now, we often hear about that leaky mitral valve, which can often be prolapse versus regurgitation. Could you go into a little bit of detail about that?

Walter McGregor, MD: Sure. And they're kind of the same, or they're used interchangeably, let me put it that way. If you look at mitral regurgitation, regurgitation just means blood traveling in a reverse direction through the valve. And sometimes that regurgitation or reversed direction of blood flow is related to a floppy or prolapsed valve. Sometimes that reversed or regurgitant blood flow is related to too much stretch on the structure around the heart valve, again, citing the examples of atrial fibrillation or people with heart muscle failure, ventricular dilation. But most of the time, what we're talking about is regurgitant or reversed blood flow is related to more floppy mitral valve disease.

Host: What are some of the main signs and symptoms that a patient might present that indicate mitral valve disease?

Walter McGregor, MD: Yeah. It's oftentimes more breathing limitations. So, dyspnea, orthopnea can certainly play in later in the stages of the disease processes. Early on, sometimes it's very difficult. People can present with just fatigue. They're not feeling well, they don't have the same drive or energy that they used to. They're not sure whether this is related to the fact that they're now two or three years older and just resuming an exercise routine or whether this is truly something that's a problem. And so oftentimes, people find their physicians to provide some guidance, and that's just when kind of a new murmur is detected. So, it's somewhat incidental at times. But I think really most of the time, it's just an astute primary physician or an astute clinician that picks up on the fact that this may just be something more than we're a few years older than we used to be.

Host: Now, we're all familiar with the dyspnea and the murmurs that may be associated with mitral valve disease. But what are some of the subtle findings that physicians may miss in our exams?

Walter McGregor, MD: Yeah. It's truly, I think, a great auscultatory exam with a stethoscope helps to clarify. And so, there aren't too many subtle findings early in the disease process. Clearly, if patients are a little bit more prone to heart failure, they can look for irregular heart rhythms that may be consistent with atrial fibrillation, check for a little bit of edema in the legs. Sometimes edema in the abdomen is overlooked. The legs look okay, but a little bit of abdominal bloating is a sign of volume retention. But I would say that the subtle aspects of early stages of mitral disease are most often best clarified just with a great stethoscope exam and then, low threshold for obtaining an echocardiogram.

Host: Absolutely. Now, if mitral valve disease is suspected, when should a patient be referred to a cardiologist versus a cardiac surgeon?

Walter McGregor, MD: Sure. That's a great question. And what you're looking for is to get the patient into the hands of someone who has expertise in mitral valve disease. And I use the word passion to open our podcast. I think someone that has a passion for mitral valve disease is very important too. And so, if there's a leading cardiologist in anyone's medical community or a leading cardiac surgeon in anyone's community that really champions themselves as being a leader in the mitral valve space, that's the person to get your patients into for an evaluation.

Certainly from a surgical standpoint, we engage very early on in people's disease processes. It's very common for me to see someone in the office and have a conversation with them about options. Sometimes options can be close, watchful waiting. Sometimes the options that are best are to think about heart surgery, you know, in the next six months or so. And sometimes, it's more urgent. Sometimes, it's, "Hey, we really should be talking about surgery here in the upcoming weeks." So, a lot of the decision-making on whether or not to proceed with surgery, what type of surgery, what type of procedure, and, of course, the timing is best made by someone who has a lot of experience managing patients with mitral disease. And so, I'd say, you know, less to do with the title and more to do with someone who has some experience in the space is the best person to get your patients over to.

Host: Absolutely. And we're showing in medicine that the expertise within that little niche is really improving patient outcomes. What are the long-term patient outcomes specifically associated with early referral to a cardiac surgeon?

Walter McGregor, MD: Yeah, I think I'll take a step back even. I mean, of course, I'm going to promote early referral to a cardiac surgeon because I'm a cardiac surgeon, right? There's got to be a little self-promotion in this podcast, huh?

Host: Absolutely. We want your expertise and we to see your take on it.

Walter McGregor, MD: But I think early referral to someone who has experience is key. And if you can get your patients into someone with an experienced eye in the mitral disease space, what you're going to find is that they're better able to make the decision as to who can wait and who can continue to carry out their life without having to take a pause in their personal lives and undergo surgery versus this is, you know, understanding who really should be proceeding sooner than later.

What we've seen, Dr. Habib, over honestly decades of data are that if we're able to get our patients to people who have experience with judgment, experience with their technical skills and their ability to achieve mitral valve repair with a high rate of success and a very low complication rate. What we see is that we're actually adding years onto their lives, whether they have symptoms or not, and their quality years as well. So, patients that have especially floppy valve disease or degenerative valve disease and those most specifically that have a ruptured chord or kind of a disruption in the mitral support mechanism and a true anatomic abnormality, operating on those patients earlier in the disease process decreases the future of heart failure admissions and actually adds time onto their life expectancy.

Host: That's fantastic.

Walter McGregor, MD: So yeah, it is pretty powerful stuff. In the world of heart surgery, there aren't a lot of things that allow us to keep people on a normal life expectancy curve, and this is one of them. It's truly a chance to almost cure a disease state and eliminate it from a patient's month in and month out life. And so, it's pretty exciting.

Host: I love that you highlighted, you know, these patients have better long-term expectancy. But more importantly, they have better quality of life. How does early referral to a cardiac surgeon also empower the patient, if we want to specifically talk about improvement of empowerment of the patient?

Walter McGregor, MD: Yeah. And I think that's one of our main missions when we sit and have consultations with people just to take a step back at data, if you kind of look back over the last couple of decades, there was a lot of leadership provided by the Mayo group, Dr. Enrique Serrano and Dr. Schaff, who kind of dealt with, some people kind of in the mitral world view their patient population as maybe being a little exceptional. The executive that can afford to fly to Rochester, Minnesota and undergo mitral surgery and, of course, their results are all going to be good. But really, what we've seen over the last couple of decades is that in people who have kind of dedication to the field and to the specialty, those same outcomes can be achieved. And those outcomes are really along the lines of greater than 95% likelihood of undergoing a valve repair and a less than 1% risk of having any major troubles with surgery, meaning 1% or less mortality risk. And so in people that are experienced with mitral valve work, they're able to achieve those types of outcomes on a pretty consistent basis for patients, whether they're in Rochester, Minnesota, Pittsburgh, Pennsylvania, which is where I'm based, and a lot of other high profile mitral centers throughout the country.

And so, sitting and talking with patients and empowering them allows them to make decisions for themselves about not just whether or not they should undergo mitral valve treatment. But when they want to undergo this and also whereabouts throughout the country they want to undergo this type of therapy and take an interruption in their life and devote two or three months to recovery and then move on with life.

The American Heart Association and the Mitral Foundation designated roughly about maybe a little over 20 reference centers throughout the country for mitral valve repair work. We were fortunate to be one of them. It's also a lot of hard work that we've put in to be one of them. So, I think what we really try to do is empower patients in consultation to learn about their disease, decide when they want to take an interruption in their life and dedicate to this, to invest in this to provide better quality of life and more longevity going forward. But we also really offer them our recommendations on where they should obtain opinions. By and large, this is elective work or semi-elective work. And so, people often have the opportunity to obtain multiple opinions. And so, we openly provide guidance for them.

Host: It's certainly so impressive that at Allegheny, you guys have achieved that referral center status because it is so elite if there's only 20 centers across the country, very impressive work. And that less than 1 percent mortality rate is also an incredible number. As a fellow surgeon, you don't often see major surgeries like that, that have a less than 1% mortality. So, I definitely applaud you for that rate. Now, once a patient is referred to you, what is involved in their workup?

Walter McGregor, MD: Sure. Now, first of all, thank you for commenting on your observations. I mean, it's a learned observation and it's a very high bar. The centers that are included in that, it takes lot of work and it's also true dedication by our entire mitral valve team. We work very hard to understand every individual's disease state, make sure that we have a genuine appreciation of any risks that they might have so we can mitigate that risk and come up with the best therapy option for them.

You know, part two of your question was what's involved with the workup. And a lot of our workup focuses around understanding what the risks are for any given patient as well as what are some of the nuances to their valve repair. I think, for sure, one of the foundations of imaging is a transesophageal echo. And so, sometimes patients come to us most of the time with a surface echo, transthoracic echo. Sometimes even with a transesophageal echo. And if the quality of our outside transesophageal echo is high end, then we don't need to repeat it. But sometimes even if the quality is high end, we find ourselves repeating just to look at more specific therapeutic options. And so, periodically, our patients will need to have repeat transophageal echos, but really just to make sure that we're making the best decisions for them.

I think additionally heart catheterization is important. Most of the time a heart catheterization is not really necessary until the decision has been made to move ahead with some sort of mitral treatment or mitral surgery. And then, CT scanning has revolutionized healthcare. In the medical world, of course, you all make the joke that's replaced the physical exam, which of course is not true.

Host: Not at all.

Walter McGregor, MD: Yeah, far from it. But it really does provide a lot of insight. And the fidelity of the imaging is so high end anymore that allows pretty precise surgical planning. And so, we have a special CAT scan protocol that we perform for all of our patients that were contemplating surgery, which really helps us to clarify, "Hey, are they best with some transcatheter approach to mitral repair? Are they best approached with robotic heart surgery or more traditional heart surgery through a sternotomy approach?" And so, it's this constellation of transesophageal echo, CT scanning, and then ultimately heart catheterization that allows us to make good decisions for people. I think in the not too distant future, we already have a protocol established to potentially obviate left heart catheterization for patients as well and rely more on dynamic coronary CT imaging, which would really wrap up the workup with all kind of minimally invasive workups, which would be a great step forward for our patients.

Host: Oh, definitely. I mean, if you can take a CT scan over catheterization, that just saves the patient one additional procedure.

Walter McGregor, MD: It really does.

Host: Now, you mentioned different types of surgery. So, what are the main differences between minimally invasive surgery, robotic surgery, open heart valve surgery, and how do you determine patient eligibility?

Walter McGregor, MD: Sure. The first thing that I really try to emphasize for our patients is that no matter what treatment that we guide them towards and recommend, we're always looking to partner with our patients on these decisions. Oftentimes, the safe answer is fairly obvious, but sometimes it's not. Sometimes there are options that are less invasive and more invasive and what helps us to make final recommendations and provide guidance for patients is, "Hey, what's going on in their lives?" Sometimes, patients they're in a life position where they don't have the ability to invest three months for a full recovery from standard open heart surgery. And so, then we start to look at more temporizing options that gets them to a station of life where they can really make that investment in their own health. And so, we're truly trying to invest with our patients on a one-on-one basis to help them make good decisions for themselves.

I think taking a step back and kind of looking at some of the more medical decision-making, if we look purely at mitral valve disease, I would say most patients with isolated mitral valve disease are equal candidates for both minimally invasive approaches, as well as kind of standard sternotomy approaches. What I mean by that is that most of the patients that we see with isolated mitral valve disease, we really look at them through the lens of you're probably a robotic heart surgery candidate.

Robotic heart surgery provides a lot of advantages. Obviously, it's less invasive, it's small incisions. There's a cosmetic benefit, there's a return to independence benefit too. But, you know, it's not magic, it's still heart surgery, but people do regain their independence. They're back to driving and even getting back to work much sooner. But all of that is countered by whatever we think is the safest approach.

Patients that have a fair amount of iliofemoral calcification on CT scanning or patients that have a moderate or greater amount of calcium around their mitral valve, we tend to stick with more traditional heart surgery for those patients. Debriding the calcium around heart valves, for example, can create some calcific embolization and our ability to scavenge that embolization and remove it as a potential source of stroke or embolic event is just greater and safer through a traditional approach. But outside of that specific circumstance, we really view most patients just based on their mitral valve pathology as being good candidates for robotic heart surgery.

Host: Now, you did mention that there are some obvious differences between robotic minimally invasive surgery, open surgery, you know, smaller incision, less downtime. Are there any other main reasons that minimally invasive mitral valve surgery enhances the patient experience?

Walter McGregor, MD: Yeah, I think that what patients are looking for is to come in and have an exceptional mitral valve repair result, meaning, yes, they want ideally less invasive and speedier recovery is nice. But the fundamental elements of mitral valve surgery are that you have an exceptional mitral valve repair result, meaning a repair that looks almost as good as the way the Lord made it, if those are your beliefs, or nature made it. And so, robotic repair, in our hands at least, does contribute towards that goal. The robotic technology is pretty sophisticated. It allows up to 10 times magnification of the mitral valve. The dexterity of the robotic instrumentation really mimics almost all of the degrees of freedom that a human wrist has. And so, our ability to magnify the valve, make precise cuts and precise reconnections of the valve leaflets, all through small incisions, it adds to what the patient experience is from a recovery perspective. But most importantly, it adds to a durable valve repair. And we're always trying to find the treatment that is safest and also provides the best durability. We want our patients ideally to undergo this once and move on with the rest of their lives and not have to worry about it again. And our experience is that the robotic repair does lend to that ultimate goal of one time and a lifelong repair.

Host: That's fantastic. Well, thank you so much for joining us today, Dr. McGregor. You shared so many tidbits about how early repair and early referral to a mitral valve disease specialist can improve outcomes and life expectancy of the patient. Are there any other take-home points that you would like to leave with our audience today?

Walter McGregor, MD: Yeah, I think probably the biggest take home is what you all have achieved here today, Dr. Habib, and that's increasing education and increasing awareness. I had mentioned that some of the studies that were referenced from the Mayo Group, for example, have publication dates all the way back to like year 2000 or even 1999. And so, data had been around. Anything that you can do to increase awareness and education throughout our physician community is extremely powerful.

I guess the take-home message I would just leave for all of my fellow physicians is when in doubt, early referral to someone who has an interest in mitral valve disease is best. We Never mind sitting and talking with someone who doesn't need surgery. We like to spread that good news every now and then ourselves as surgeons. So, feel free to utilize us as a resource.

Host: If somebody wanted to refer a patient specifically to your center, how would they make that referral?

Walter McGregor, MD: Yeah, I am personally available on our website. Reaching us through our website is great. 1-800-DOCTORS is Allegheny Health Network's standard referral line. And so, I think that's something that's easy for all referring physicians to remember. They can always pick up the phone or ask their patients to pick up the phone, call 1-800-DOCTORS and just ask to have an appointment set up for myself, Walter McGregor. I'm easily found on the internet as well, so I think some good options that are easy to remember for people.

Host: Perfect. Thank you so much, Dr. McGregor, and enjoy the rest of your day.

Walter McGregor, MD: You as well, Dr. Habib. Take care.

Rania Habib, MD (Host): Thank you for listening to this edition of AHN Med Talks. To learn more or to refer a patient, please call 844-MD-REFER, that's 844-MD-REFER, or visit ahn.org. I'm your host, Dr. Rania Habib, wishing you well.