Michael Smith, MD (Host): This is Meaningful Medicine, a Novant Health Podcast. I'm your host, Dr. Mike. And Dr. William Hammill, a pediatric cardiologist, joins me today, and we're going to discuss sudden cardiac arrest in young athletes. Dr. Hammill, welcome to the show. So, sudden cardiac arrest is obviously a rare thing, thank God, but it's very serious, incredibly serious. So, maybe we can start, just so everybody understands, what are we really talking about here? What's going on, and how is it different from just a regular heart attack?

William Hammill, MD: Sure. Well, great question. We'll start with a heart attack. Most heart attacks in older adults are usually because of coronary artery disease. So, an easy way to think about it is not enough blood flow to the heart muscle, so goop in your coronary arteries. And over time, that narrowing doesn't allow enough blood flow to go to the heart muscle. And ultimately, if the supply, meaning the amount of blood going to the heart muscle doesn't meet the demand that the heart has for blood flow, then the heart has a heart attack. And that can cause lots of different things like rhythm changes and those sorts of things. But basically, it's just not enough blood flow going to the heart muscle that ultimately leads to the problems.

In kids and young adults, we don't typically think about them having goop in their coronary arteries. So, a sudden cardiac event is usually secondary to a rhythm change of the heart. And there are a host of things that can cause those rhythm changes that ultimately lead to that. So, to put in perspective, Mike, there's 350,000 adults going down in our country every single year. So, that means three 747s a day every single day, 365 days a year. That's how many adults have an acute cardiac event. In pediatrics, it's about one in a hundred or 200,000 kids. So, there's 2000 kids a year in our country. So, to put that in perspective to 350,000 adults, 2000 kids.

The challenge is every single one of those 2000 kids we read about in the Charlotte paper, whether it was in Iowa or Los Angeles, or in your state of Texas, because it's devastating, right? This is a young life. It's a devastating loss of life when that happens. So while it is very rare, it pulls at all of our heartstrings as parents, as communities and really as providers to say, "Hey, what can we do to minimize the risk for our kids to try to pick these things up when we can?" Because it is so devastating when it does happen.

Host: What are some of the underlying conditions that you have discovered that can maybe lead to this, type of sudden cardiac arrest in, otherwise, healthy kids, right?

William Hammill, MD: Absolutely. Yeah. That's also one of the challenges, right? It's not one thing. So, it's not one thing that we say, "Okay, this caused all 2000 of these events that occurred in the last calendar year."

So, probably the most common one is something called hypertrophic cardiomyopathy. It's when the heart muscle is not normal. It tends to be bigger and thicker than normal, and there's risk of not only obstruction, not like coronary obstruction, but obstruction to blood flow, but also acute rhythm changes of the heart so that you're in a normal rhythm and then you suddenly go into an abnormal rhythm that makes you pass out and, ultimately, doesn't provide enough circulation. So, that's the most common one. And some people think that the incidence of that is as high as one in 500 people. So, that means you and I both went to high school with somebody with hypertrophic cardiomyopathy, and they may or may not have even known it. So, that's a big, thick heart.

The other side of that are people that have enlarged or dilated hearts. And we're learning more and more that sometimes that's hereditary, but sometimes that's after just a bad viral illness. They had a bad illness one to six or so months before this event, and their heart was damaged and it got big and dilated and ultimately led to the problem.

They're things like coronary anomalies, so not goop in the coronaries like we talked about with the adults, but where the coronary arteries don't come off in the normal space where they're supposed to. So, it can cause compromise to a coronary and that's always really scary because you don't know that you have a coronary issue sometimes until you begin to have symptoms.

 And then, there are rhythm things, meaning that the plumbing is all normal, right? So some of these are plumbing problems, meaning that the pipes, the heart itself is not normal. Sometimes it's electrical problems, meaning the heart, if you could hold it in your hand, would be perfectly normal. But there are electrical problems, rhythm problems that can occur. Many of them are hereditary. And so, you can be in a normal rhythm and then suddenly go into an abnormal rhythm. So, things like long QT and arrhythmogenic right ventricular dysplasia. And all have crazy long names, but they are almost all inherited 50/50 from one of the parents, and sometimes there's new mutations or new cases. But that becomes part of what's important for us as communities, as families, as providers, is to sort of try to see if we can figure out who are those kids that are at most risk.

Host: So, are there any early warning signs then that maybe parents and coaches can be more aware of? Understanding that what you had just said is that some of these conditions, some kids don't even know they have them.

William Hammill, MD: Sure.

Host: is there any symptoms at all or what could parents and coaches look for?

William Hammill, MD: Yeah, I would say at least 50% of these kids will have symptoms before they ultimately had the event that led to it, okay? So, you were correct. We can be in tune to that. So, it's things like chest pain associated with exercise or passing out with exercise, or we've all seen or been around family members or people at church or people in the choir or whatever, that will get lightheaded and dizzy and pass out, that's called a vagal thing. And it's very, very common where you vasodilate, and it just means you don't have enough blood flow and you get lightheaded and dizzy and pass out. That's very, very different from "I rounded third base and was heading to home and passed out" or "I was doing the sprint on a hundred-yard dash and passed out," or chest pain associated with exercise or palpitations with exercise, the sensation that your heart is racing or beating real fast.

So, I think that, if 50% of these kids are going to present, are going to have symptoms, usually those things are things that can be picked up if we're attuned to it as parents, as coaches, and then ultimately as providers. So if you're referred to me for chest pain associated with exercise, the onus is on me to prove that you don't have any of those yucky things that we know can be associated with a bad outcome.

Host: How important is screening young athletes before they begin a new season? And are there certain screening techniques that you recommend over others?

William Hammill, MD: Sure. Well, that's a loaded question, and I'll give you my take on it and then explain sort of both sides of the story. Here's what I would say, we absolutely know that pre-participation screening is critical, right? So, I want every child to have a physical exam, preferably by the provider that's watched them grow up, that knows their family, that's been associated with this for a long time and has been following that child for years and knows kind of the history and what's normal for Johnny or Susie or not. So, your primary care pediatrician or family physician or, advanced practice provider is that person much of the time. Now, I know that not everyone has that access to the care. And so, we do screening exams and we do offer things that can be done.

What I'll tell you with that is that there've been some good papers in the past that have shown that, if you really, really want to decrease the risk of sudden death in our communities, about 80% of the opportunity to do so is going to come from history, 10% from the physical exam, and maybe another 5% from the ancillary tests that we do. So if I could stress one thing to families, is make sure that your kids get a really good history and physical exam by somebody that knows you and your family. And I'm not opposed to the school physicals where you come into the gymnasium and do those, but I want to make sure that that history has been thoroughly gone over and reviewed. Because if you have a grandfather and a cousin and an uncle who all died suddenly, then there's a red flag there that we'd really need to look into. And you may not have ever had a single symptom. So, history, history, history, history. Physical exam after that.

And then, there are ancillary tests like electrocardiograms, EKGs that we do or even ultrasounds, echocardiograms. And clearly, those provide additional insight and help in trying to decide do you have a risk or not. But if the question is, do I line a thousand kids up and have them get an EKG? Or do I line a thousand kids up and take a really good history and do a physical exam? My money is on the history and physical exam every single time. The EKG can provide additional ancillary information. But one of the challenges is we have 100,000 kids in Mecklenburg County and the surrounding seven counties that are doing sports every year. We're going to have a sudden death every year, one or two. It's just the numbers. If we said we're going to do an EKG on all 100,000 kids, there's two major health systems in our community, we're going to divide up those EKGs. That means we're each going to do 50,000 EKGs. No one wants to read the EKGs other than having a pediatric cardiologist do it on the child. And so, that's 50,000 EKGs. We're going to take two weeks off a year. That means a thousand EKGs a week, where each of our health systems are going to read, that's 200 a day. So, unless we have AI mechanisms, unless we have other ways to help us interpret these tests, a screening for all is going to be problematic and challenging until we get to a place where we have more providers trained or we have more ability to use artificial intelligence and other ways to get the answer to that. So, that's a long-winded way to say history, history, history, physical exam, and then some of these other tests are helpful as well.

Host:  You know, with EKGs, and please correct me if I'm wrong, maybe you can catch some of the anatomical things like an enlarged heart and stuff like that. But if it's an electrical problem like you mentioned and they're not having that problem at the moment, you're just going to catch a normal rhythm and not really see anything. So, there is some limitations right there, right?

William Hammill, MD: Sure. There are a few electrical things, something called long QT where you can see it on the resting electrocardiogram. But you're right, there are a number of those where the resting, and particularly for a coronary anomaly, unless you're having symptoms, that EKG is most likely going to be perfectly normal.

The other challenge, Mike, is that between 10% and 15% of EKGs, the computer may think are abnormal or there may be a slight abnormality with it, whereas it's not something that we would necessarily restrict a child from participating in sports. So, the EKG may be abnormal, but the child's not abnormal. And so, ultimately, that's 15% of those 100,000 kids in Mecklenburg County that are going to need to have additional testing or visits or those sorts of things.

And so, when it's your kid, there is no dollar amount that you would not spend to try to make sure that they didn't have an issue on the sports field, right? But in the public health perspective, it does become problematic. And I don't want a child to sit out and not be able to participate because they couldn't get in to see me or one of my colleagues. So again, I'm for those ancillary tests when it makes sense to do it. So if there's a family history, if there's an abnormal physical finding, if there's another thing that's concerning, it makes sense to do those things, to provide you additional information to narrow it down even more, if you will.

But is there a test or anything that we could do that would completely eliminate any risks? The answer is no. We can eliminate most of them, and we certainly can make them feel better. I tell families that I want to put it in perspective, and I tell them that they took far more risk getting on the interstate and coming to see me. Once we've done all these testing and things, and when you put risk in perspective, probably more risky to get on the interstate once we've figured out that everything is okay.

Host: So, what can coaches in schools do then to kind of prepare for a potential cardiac event on the field?

William Hammill, MD: Sure. Well, I think making sure that every child has that history in the physical exam and plus or minus these ancillary tests are huge. So, schools really need to mandate that. A lot of states have mandated the physical forms, which is good. And I think most of our schools do a great job of that, not trying to skirt the system and get a kid in otherwise.

I think secondary prevention is also something that we don't want to lose sight of, meaning that you never want something to happen. But if it did happen, there are good things that we can do that will save a child's life, if you will. So, we've all seen the Damar Hamlins and things on the news about athletes that have dropped. Well, the same thing applies to every one of our high schools, that if we have a kid that drops on the field, we want to make sure that we have people around that are trained in CPR, that know how to access the emergency response system, that know where the AED is in their school or on their sports field, or who has the AED, and make sure they know that they have someone that's trained and knows how to use it.

So, mortality from an acute rhythm, change of the heart is 10% per minute. If you do really, really good CPR, it goes down to about 5% per minute. But if you're waiting for the ambulance to arrive and the mortality is either five or 10% per minute, depending on whether you're doing good CPR or not, I don't like that math, right? I don't like to know that I've got to wait. If it takes them 10 to 20 minutes to get there, then the likelihood of a good outcome goes way down. But there are great studies that show if you can get that AED to the patient, to the child, to the coach, to the family member in the stands, in a timely manner in conjunction with good CPR, that the outcomes are significantly better. So, making sure that everybody has that emergency response system, making sure they have people trained in CPR, they know where the AED is, they know how to use it, that's going to save a lot of lives.

Host: Right. Right. For the audience, can you just give us a one or two-sentence definition of the AED?

William Hammill, MD: Sure. It's basically a defibrillator like you would see on television on an ER show where they grab the paddles and they shock the heart. This is one that it doesn't require any hands on. So, it's a device where you'll put the stickers on the patient on the front of the chest, and sometimes on the front and back. It analyzes the heart rhythm. And then, if it senses an abnormal heart rhythm, it will deliver a shock just like we see on TV, and hopefully reestablish that normal heart rhythm.

So, they've been game changers because a lay person in a very short amount of time can be trained how to use an AED. And now, AED training is a part of every CPR training, whether you're taking American Red Cross or the Heart Association, or anyone else, they're all teaching you how to use AEDs in conjunction with CPR because, as I said, we've learned that the quicker that you can get electricity to someone to reestablish a normal rhythm, the more likely a good outcome.

Host: Yeah. To summarize Dr. Hammill, what gives you hope when it comes to preventing these tragedies? What do you see happening, hopefully, in the near future to really make an impact?

William Hammill, MD: Sure. Well, I think we're learning more and more about the genetics behind a lot of these things. We're learning more about how to look at gene mutations. And so, not only are we figuring out earlier who might be at risk, but we're also tailoring therapies on that, so that's very exciting. So, the future, once we figured something out, I think is great.

Honestly, another thing that I'm super proud of is parent advocacy. Unfortunately, it's oftentimes after a catastrophic event, but we have many, many great programs in our communities going on now. And if you look back to their origins, almost always, it's a mom and a dad who was touched or affected by this, who have started a grassroots effort to get CPR training and to get AEDs in the school and to make sure that there are some school systems where every child is trained in CPR before they graduate high school. And so, things like that are in conjunction with what we're able to do on the other end of the spectrum with the science part of it are critical. And I do think that those two are moving hand in hand, and it's great to see.

So, every year there's a sudden death conference that's put on. and A day and a half of that is all the families are invited that have been touched by these things. And to see and hear all the advocacy that's going on and the ways that families are working with school systems and working with their athletic teams is just phenomenal. It just brings a tear to your eye that they're so passionate and so involved and want to make sure that the same thing doesn't happen to somebody else's child.

Host: Dr. Hammill, I got to tell you, this was a very informative show. Thank you so much for coming on today and sharing your expertise.

William Hammill, MD: Yeah, thanks very much for having me. I really appreciate it.

Host: For more information, you can head over to novanthealth.org or explore more health insights at healthyheadlines.org. If you like this podcast, go ahead and share it on your network and take a look at our podcast library for topics that might be of interest to you. This is Meaningful Medicine. I'm Dr. Mike. Thanks for listening.