By: Lindsay May, MD, FAAP, FRCPC & Shaji Menon, MD, MS, FAAP, FACC, FASE
An 8-year-old boy playing his first season of peewee football dies suddenly after practice. A 10-year-old girl's heart stops beating just as she takes her long-awaited turn to go down a water park slide. A 16-year-old high school basketball player collapses on the court after making the game-winning shot.
What is sudden cardiac arrest?
Sudden Cardiac Arrest (SCA) is a life-threatening emergency that happens from an "abrupt and unexpected loss of heart function leading to loss of consciousness and collapse." SCA can be fatal if not treated within minutes. Survival outside a hospital depends on people nearby
calling 911 and prompt bystander emergency response.
Are there warning signs for SCA before it happens?
When SCA happens to seemingly healthy young people, there is usually no obvious injury or medical reasons the patient or family knew about. Some young people who suffer SCA may have previously experienced heart-related symptoms, such as shortness of breath, chest pain, or
fainting, that weren't thought to be anything life-threatening. Others never had any symptoms of heart problems until the SCA event.
When can sudden cardiac death happen to young people?
Sudden cardiac arrest is thought to be a leading cause of death in young athletes, but it also affects young people not involved in organized sports. It can happen during exercise or at rest, or even during sleep. In some cases, young people can die from sudden cardiac arrest days or weeks later from brain damage that happened during the SCA.
What causes sudden cardiac arrest in young people?
Some possible causes of sudden cardiac arrest in children and young adults with no previously known heart problems:
Hypertrophic cardiomyopathy. Usually inherited and often undiagnosed, this is the most common cardiovascular cause of SCA in young people. Muscle cells in the heart's lower chambers, called ventricles, thicken. This can cause abnormal heart rhythm, especially during exercise. Other types of
pediatric cardiomyopathy may also play a role.
Coronary artery abnormalities. Defects in the way the coronary arteries connect to the heart can lead to decreased blood supply to heart muscle during exercise and cause cardiac arrest. Young people with coronary artery abnormalities usually are born with them but may not notice any symptoms until they are older.
Primary arrhythmias. In people with structurally normal hearts, sudden cardiac arrest can sometimes be caused by undiagnosed genetic conditions that affect the heart's electrical impulses. For example, these include:
Arrhythmogenic right ventricular dysplasia (ARVD). With this inherited condition, some of the heart's muscle tissue gets replaced with scar tissue.
Myocarditis. Usually triggered by
an infection, myocarditis means the walls of the heart are inflamed. Most myocarditis cases in children happen when a virus such as an
enterovirus gets into the heart. It can also be caused by bacterial, fungal or parasite infections, and allergic reactions to some medications.
Marfan syndrome. This connective tissue disease can lead to tears in the heart's aortic blood vessel. People born with the condition, who tend to be tall and have long arms, may not realize they have it.
Commotio Cordis. Caused by a blow to the chest directly over the heart at certain points in the heartbeat cycle, commotio cordis is more common in sports with projective objects such as ice hockey, lacrosse, and
Stimulants and medications. Certain prescription medications and stimulant drugs can affect heart function. With
energy drinks popular among adolescents, there are concerns that large amounts of caffeine combined with other substances contain
could contribute to irregular heartbeats and sudden cardiac arrest.
Are there ways to help prevent sudden cardiac death?
There are steps families and communities can take to lower their risk of sudden cardiac death in young people:
Regular well-child visits and sports physicals. The American Academy of Pediatrics (AAP) recommends all children receive regular
wellness visits. These visits are a chance to get a complete physical exam and detailed
health history to help identify risk factors that may contribute to SCA.
Pre-participation exams also are important, even if a child is not involved in organized sports because gym class and recreational activities can―and should―involve plenty of
exercise! A screening form that can be completed anytime by patients and parents with their primary care provider, to help decide whether a visit with a
specialist is needed.
Know your family history. Gather the heart health history of blood relatives (children, siblings, parents, aunts and uncles, nieces and nephews, grandparents and cousins), and share with your medical provider. This can help guide questions during well-child check-ups and sports physicals.
Community life support training and automated external defibrillators. The AAP supports age-appropriate life-support training for students, including
CPR for older children and all staff, in all schools starting with the primary grades. It also encourages having automated external defibrillators (AEDs) near school athletic facilities and training so school personnel and older children know how to use them. In cases of sudden cardiac arrest, AEDs can quickly deliver an electrical shock to return the heart rhythm to normal.
Should all young people be screened for sudden cardiac arrest risk?
Performing mass screening
tests like electrocardiogram (EKG) and echocardiogram (ultrasound of heart) for all young people or in athletes to identify risk factors for sudden death is not currently recommended. The concern is that high falsely positive test results in young people resulting in anxiety and additional testing. Also, not all events can be picked up by these tests.
However, recognizing warnings signs and risk factors, accurate history-taking and cardiology and
genetic screening for patients at higher risk because of family members with concerning heart conditions or an SCA can be very effective ways to help reduce the risk of sudden death.
What's the outlook on sudden cardiac arrest statistics in the young?
There is a lack of reliable information about the incidence and cause of sudden cardiac death in young people. However, the CDC recently established a
Sudden Death in the Young Case Registry for babies, children and young adults up to age 20. The goal of this registry is to help create a better understand how often and why SCA happens in young people—and how to help prevent it.
Although sudden cardiac death in young people isn't common, even one life lost is too many. Take steps that can help reduce the risk of these tragedies, such as scheduling regular well-child visits sports physicalsm and encouraging CPR and AED training in your community.
About Dr. May:
Lindsay May, MD, FAAP, FRCPC, is an Assistant Professor of Pediatric Cardiology and on faculty at Primary Children's Hospital, University of Utah. Her medical training was primarily in Canada, with her cardiology fellowship and advanced heart failure and transplant training done at Stanford University. Within the American Academy of Pediatrics, Dr. May is a member of the Section on Cardiology and Cardiac Surgery (SOCCS).
About Dr. Menon:
Shaji Menon, MD, MS, FAAP, FACC, FASE, is an Associate Professor of Pediatrics and Radiology at Primary Children's Hospital, University of Utah and the Medical Director of Single Ventricle Survivorship Program at the University of Utah. Within the American Academy of Pediatrics, he is a member of the Section on Cardiology and Cardiac Surgery (SOCCS) and the Section on Child Death Review and Prevention (SOCDRP) and a contributing author to
Common Cardiac Issues in Pediatrics (AAP, April 2018). Dr. Menon is also a fellow of the American College of Cardiology and the American Society of Echocardiography.