The large majority of these sudden deaths are related to underlying cardiac conditions that were undiagnosed beforehand. The sudden death is usually caused by a life-threatening cardiac arrhythmia—either ventricular tachycardia or ventricular fibrillation.
These heart rhythm disturbances cause the heart to pump blood poorly or stop pumping blood altogether. In most cases with young athletes, intense exercise triggers life-threatening arrhythmia.
This article discusses cardiac conditions that can cause sudden cardiac death in young athletes. It also looks at what symptoms to watch for and how screening can help.
Cardiac Conditions That Increase the Risk
The age that seems to divide “young” athletes from “non-young” athletes is 35 years. Above 35 years of age, sudden death in athletes is usually caused by coronary artery disease due to atherosclerosis.
Below 35 years of age, sudden death in athletes is commonly related to congenital or genetic heart conditions. Some cases can also be caused by infections or inflammatory disease.
The cardiac conditions that may increase the risk for sudden death fall into two general categories: structural and non-structural causes. Structural heart disease is when the heart is structurally, or anatomically, abnormal. With non-structural heart disease, the heart has “electrical” abnormalities causing abnormal heart rhythms.
Structural Heart Disease
Here is a list of structural heart diseases that can increase the risk for sudden death in young athletes:
Hypertrophic cardiomyopathy Congenital abnormalities of the coronary arteries Mitral valve prolapse Myocarditis Arrhythmogenic right ventricular cardiomyopathy Marfan syndrome Congenital heart disease
Non-Structural Heart Disease
The following non-structural heart diseases are shown to increase the risk of sudden cardiac death in young athletes:
Long QT syndrome Brugada syndrome Catecholaminergic polymorphic ventricular tachycardia (CPVT)
Which Causes Are the Most Common?
In the United States, the most common causes are hypertrophic cardiomyopathy and congenital abnormalities in the coronary arteries or the aortic valve. Myocarditis contributes to a smaller, but still significant amount of deaths.
The common causes of sudden cardiac death are different for various locations. For instance, a study in Northern Italy found that arrhythmogenic right ventricular cardiomyopathy was a common cause of sudden death in young athletes, while it is rare in the United States.
In general, for most of these conditions, the risk of sudden death is highest during physical activity that requires:
Bursts of extreme exertion, such as sprinting, football, soccer, basketball, and tennisIntensive training programsExercise in extreme conditions of heat, humidity, and/or altitude
Physicians may recommend limiting certain activities depending on the condition involved.
Symptoms of Cardiac Conditions
Some cases of sudden cardiac death can happen without warning. In other cases, symptoms and signs may be apparent in the weeks and months before, especially during exercise.
Some signs of cardiac distress include:
Dizziness or faintingChest discomfort or painHeart palpitations, which feel like your heart is fluttering, skipping a beat, or beating too fastUnexplained fatigue with usual exerciseShortness of breath
See your doctor immediately if you experience any of these symptoms or warning signs.
Screening Young Athletes
Cardiac screenings can help to identify “silent” cardiac abnormalities that are potentially deadly. The American Heart Association recommends that athletes undergo a 14-point medical history and examination before participating in sports.
However, standard physical exams have been found to miss some of the conditions that cause sudden cardiac death. In a study of 115 cases of sudden cardiac death, only one was correctly identified through a physical examination and medical history.
Some diagnoses may be missed because the athletes don’t have any symptoms. Research shows that 60% to 80% of athletes who had sudden cardiac death did not have any symptoms or warning signs.
An electrocardiogram (ECG) can help detect some silent cardiac conditions more than just a physical exam alone. Research shows that ECG is about five times more sensitive than medical history questions and 10 times more sensitive than a physical examination. It also has a lower false-positive rate than medical history and physical exam.
The AHA hasn’t recommended mandatory ECG screening programs for young athletes. However, it does encourage athletes to attend local ECG screening programs that are well-organized and have adequate resources. That should include participation from medical professionals, including pediatric cardiology specialists.
If your physician finds abnormalities during your examination or ECG screening, you’ll be referred to a cardiologist for further testing.
Summary
Sudden cardiac death in young athletes can be caused by a number of different conditions, including both structural and non-structural heart disease. Sometimes, symptoms may be present beforehand, but most of the time it can happen without warning.
Cardiac screenings can help to identify abnormalities. Research shows that ECG can help detect some cases that wouldn’t be found by physical exam alone.
A Word From Verywell
Exercise has clear benefits for your overall health. The risk of sudden cardiac death is rare, but it’s important to be aware of symptoms and get regular check-ups with your doctor.
Talk with your doctor about your personal and family history of cardiac disease. If you experience any symptoms, like dizziness or chest pain, stop exercising and contact your doctor.
