Sudden cardiac arrest in young people is very rare, with approximately 2,000 events in the U.S. annually in people under age 25. So, when two young, high-profile athletes made national headlines in 2023 after suffering cardiac arrest on the field and court, the sudden and extreme nature of these medical events further rattled the nerves of parents and pediatricians when identifying potential heart issues in kids.
In the Talking Pediatrics episode, “In a heartbeat: Outpatient screening to determine cardiovascular risk,” host Dr. Angela Kade Goepferd talks with pediatric cardiologist Dr. Chris Carter about screening student athletes and all young patients for heart issues in the primary care office. Dr. Carter is co-medical director of the electrophysiology program at The Children’s Heart Clinic.
Cardiac arrest in kids
Sudden cardiac arrest happens when the heart suddenly and unexpectedly stops pumping, causing blood to stop flowing to the brain and other vital organs. Kids who play sports are about two and a half times more likely to have cardiac arrest than kids who aren’t participating in sports, but heart events happen in non-athlete populations as well.
The two most common causes of cardiac arrest in kids are:
- Hypertrophic cardiomyopathy (HCM) accounts for approximately 40-45% of cardiac arrests in kids. HCM is a genetic abnormality that increases the risk for ventricular arrhythmias (abnormal heartbeats in the lower heart chambers) and can cause cardiac arrest.
- Coronary artery anomalies (CAAs) are a group of rare congenital heart defects. In particular, anomalous left main coronary artery (LMCA) arising from the right sinus of Valsalva (RSV) is often asymptomatic and carries a high risk of sudden cardiac arrest.
Other things that can put young people at an increased risk for a sudden medical event on the sports field or during other activities include trauma (e.g., a blunt force hit), heat stroke, drugs, supplements, and eating disorders.
Pediatric heart conditions that can lead to cardiac arrest
Cardiomyopathy is a rare disease of the heart muscle that makes it harder to pump blood effectively. There are various types of cardiomyopathies and in most cases, it causes the heart muscle to become enlarged, thick, or rigid.
One in every 100,000 children in the U.S. under the age of 18 is diagnosed annually with primary cardiomyopathy. This estimate, however, excludes children affected by secondary cardiomyopathy and potentially children who are undiagnosed because they are asymptomatic. The majority of children diagnosed with cardiomyopathy are younger than 12 months, followed by children 12-18 years old.
Symptoms associated with cardiomyopathy include shortness of breath, fatigue, chest pain, and poor appetite. However, many people with cardiomyopathy will not exhibit any symptoms.
Anomalous coronary arteries (ACAs) are abnormally connected blood vessels that supply blood to the heart. In some cases, these blood vessels could have problems with size, connections or don’t arise from the right place. ACAs are present at birth, but they aren’t usually diagnosed until the late teen years or adulthood because they don’t often cause symptoms.
Family history is a crucial part of cardiac screening
Most school athletes are required to have a sports physical exam prior to playing any sports. It’s also important to obtain a thorough family history to identify athletes at risk for heart problems.
“[Physical exams] are better than nothing, but the difficulty is we are talking about very rare problems [and] the majority of things that are going to cause sudden cardiac events have a genetic basis,” said Dr. Carter. “For example, very commonly in patients with hypertrophic cardiomyopathy, there will be a positive family history. So, a good [family] history and physical exam are really the best things we have to identify athletes with risk.”
Some good questions to include in a family history screening include “Has anyone in your family died…”
- Suddenly from an unexplained death under the age of 50?
- In a single car accident? In an unexplained drowning? Any death in a relatively young person without an obvious explanation is useful.
- From a heart attack? There can be a range of understanding of heart attacks, but the question can lead to other relevant information.
Specific cardiac questions can also be useful in a family screening, such as “Has anyone in your family been diagnosed with…”
- Hypertrophic cardiomyopathy
- Coronary artery anomalies
- Long QT syndrome (LQTS; a conduction disorder)
- Catecholaminergic polymorphic ventricular tachycardia (CPVT; irregular heart rhythm)
- Brugada syndrome (predisposed to fatal cardiac arrhythmias)
- Wolff-Parkinson-White Syndrome (WPW; an extra electrical connection in the heart)
“[Sometimes] people will say no to a general screening question, but specifically naming, at least from a cardiac point of view, the more common ones we worry about will trigger a light, and someone in the room will go, ‘Hold on, didn’t cousin so-and-so have something like that?’ So, there is utility in specifically naming those as well,” said Dr. Carter.
When it’s time to refer to cardiac specialists
Sorting through lengthy questionnaires about a patient’s health history in search of a possible heart concern can be like searching for a needle in a haystack. Dr. Carter points to a few factors that elevate the need for further screening, including:
- Exertional symptoms such as chest pain during activity, especially atypical chest pain. Kids commonly experience chest pains that are musculoskeletal, but chest pressure or discomfort that’s out of the ordinary is concerning.
- Exertional syncope (fainting during exercise) is also a red flag.
- Dyspnea upon exertion (excessively short of breath) that is out of proportion for what is otherwise normal in a health patient.
- History of a previous cardiac evaluation or intervention is another red flag. Heart surgeries that happened years prior might no longer be a concern, so it’s not uncommon for them to go unmentioned by the patient or their family.
“If any red flags come up, getting a baseline [pediatric electrocardiogram] EKG [in the primary care clinic] is a very reasonable thing to do,” said Dr. Carter. “If there’s a level of concern, I think it’s good to see a pediatric cardiologist – one, to help interpret that EKG in terms of whether it’s normal or not. Then two, to have those discussions about potential things families have questions about. I never think it’s wrong for us to see those kids.”
Note: many EKG machines in primary clinics or family practice offices aren’t set to read pediatric EKGs, so it’s important to have staff that can do a pediatric EKG to decipher results that are normal and abnormal for kids.
Dr. Carter advises primary physicians to wait to order an echocardiogram (echo) until the child has been seen by a pediatric cardiologist because often times it’s unnecessary for diagnosis and the family history usually dictates when screening begins. For example, genetic hypertrophic cardiomyopathy is almost never seen pre-adolescence; it shows up during adolescence. Even with a parent with hypertrophic cardiomyopathy, current recommendations are to start screening kids at age 10. For long QT (LQT), an EKG in a two-year-old will show if that is present. An MRI is needed for arrhythmogenic right ventricular cardiomyopathy because an EKG can actually look normal in those patients.
“Something that’s also becoming more important in [heart] screening is genetic testing,” said Dr. Carter. “Being able to discuss that and direct [families] to appropriate [genetic] testing is very useful. The genetics team [at The Children’s Heart Clinic] is a big part of the evaluation as well.”
Every child does not need an echocardiogram
Understandably, parents want to do whatever they can to avoid an injury or other medical events for their child and the idea to screen every child with an echo has circulated among families with student athletes. “[Cardiac arrests in kids] are very rare events. However, when they do happen, they are very traumatic and usually have a huge impact on the community,” said Dr. Carter.
Yet Dr. Carter advises there are several reasons why an echo for every child isn’t recommended, including:
- An echo isn’t always going to identify or rule out a pediatric heart problem – and an echo without a complete cardiac screening can provide a false sense of security to families.
- It’s important to have a pediatric cardiologist or pediatric electrophysiologist involved with the screening. An adult cardiologist or other health care practitioner who is not a pediatric heart expert can miss important pieces of information with an echo that a fuller screening can catch.
- Echoes are focused on hearts and valves; they don’t closely examine the coronaries, which is the second most common structural abnormality that is of concern in cardiac arrest cases in kids.
- Echocardiograms are expensive tests.
“I do think the [community-led] screening programs are set up with really good intentions, but appropriate screening with the appropriate tests with the appropriate people evaluating those tests is really important, and it’s just not always something that’s available at those [events],” said Dr. Carter.
The Children’s Heart Clinic at Children’s Minnesota
For more than 40 years, Children’s Minnesota and The Children’s Heart Clinic have partnered together to provide comprehensive care for children and adolescents with heart and blood vessel conditions. This partnership gives The Children’s Heart Clinic more resources and access to pediatric specialists to provide the best possible care for every child from birth into young adulthood.
The cardiology program at Children’s Minnesota treats the most pediatric cardiology patients in Minnesota and our outcomes are some of the best in the country. The cardiovascular program is the only one in the region that is part of a health system dedicated exclusively to caring for children. Read more information about the program and patient referrals here.
Project ADAM Minnesota
In 2021, Children’s Minnesota and The Children’s Heart Clinic started Project ADAM Minnesota with the mission to provide education and resources that help prevent and respond to sudden cardiac arrest in Minnesota schools. Read more about the program here.