Every year, professional athletes with no prior heart disorders suffer from sudden cardiac arrest and sudden cardiac death. While this is rare, it is the leading cause of sports-related deaths. This article examines why healthy and fit athletes with no prior heart history suffer sudden cardiac arrest, screening recommendations to prevent these, and whether COVID-19 and the mRNA COVID-19 vaccines are linked to these events.
While rare, sudden cardiac events occur in professional athletes.
Sudden cardiac events in professional athletes are usually due to an undiagnosed underlying heart condition.
Exercise decreases the risk of heart disease.
While the COVID-19 virus and mRNA COVID vaccine can have adverse effects on the heart, there is insufficient data to link them to the cause of sudden cardiac arrest or heart disorders in athletes.
While there are clear health benefits of exercise, we continue to see professional athletes like Damar Hamlin (NFL Buffalo Bills American Football Player) and Christian Eriksen (Danish professional footballer for Manchester United) collapse on the field due to heart problems. Professional athletes follow strict training programs to remain physically fit. So why are professional athletes with no prior heart or health concerns experiencing sudden cardiac events?
Sudden cardiac events in professional athletes are not new. While cardiac events in professional athletes are rare, sudden cardiac death remains the leading cause of sport-related death. Due to this, automated external defibrillators (AED) have become a requirement on the sidelines of any sporting event. Studies show that sudden cardiac death has an incidence of about 1 in 40,000 to 1 in 80,0000 athletes per year. Media coverage of the sudden cardiac events in young professional athletes has created an increased awareness of this issue. This has led to questions on why this is happening and what can be done to prevent it. Discussion of implementing additional testing and screening to ensure the heart health of all players has been a topic of debate.
Common causes of cardiac arrest in athletes
When a professional athlete suffers a cardiac event, examination and screening take place to determine the cause. Studies have shown that the majority of athletes who suffer from a sudden cardiac event have an undiagnosed underlying heart condition. These have been determined as the most common causes of cardiac events occurring in professional athletes:
- Primary electrical disease (abnormal heart rate and rhythm);
- Idiopathic left ventricular hypertrophy (thickening of the lower left heart chamber for an unknown reason);
- Coronary anomalies (a coronary artery that is abnormal or malfunctions);
- Myocarditis (inflammation of the heart muscle);
- Genetic disorders such as hypertrophic cardiomyopathy (a disease of the heart muscle that makes it harder to pump blood to the rest of the body).
Correlation between COVID-19 and cardiac arrest
There is currently no definitive proof that the COVID-19 virus or mRNA COVID-19 vaccine contribute to sudden cardiac events seen in professional athletes. There has been speculation that the perceived increase in sudden cardiac arrest in professional athletes coincides with the COVID-19 virus and vaccine mandates. Here is what we know about the COVID-19 virus and the mRNA COVID-19 vaccine and how they affect the heart.
The COVID-19 virus has known cardiac effects. It can cause the heart to beat faster than normal and produce blood clots in the deep veins and lungs. It can also cause inflammation of the heart, known as myocarditis. This inflammation can damage the small blood vessels within the heart, which can lead to the production of small blood clots in the heart. These blood clots can cause blockages that prevent blood and oxygen from flowing to or from the heart.
COVID-19 may also cause stress cardiomyopathy, which leads to a weak heart that can no longer pump blood effectively. When this happens, a stress response occurs that releases massive amounts of adrenaline. Excessive adrenaline causes the small arteries in the heart to narrow. The excess adrenaline can also attach to the heart cells, causing an increase in calcium to get into the bloodstream, which can cause the heart to not beat properly.
Studies have shown that out of 100 patients who recently recovered from COVID-19 infection, 78% of them had cardiac involvement. Ongoing inflammation of the heart, known as myocarditis, occurred in 60% of those patients. This suggests the need for continued research on the long-term cardiovascular effects of COVID-19. Additional data needs to be analyzed on high-performance athletes to determine if additional precautions are needed due to the cardiac-related effects of the COVID-19 virus.
The Centers for Disease Control (CDC) states that cardiac complications are rare after a COVID-19 infection or mRNA COVID-19 vaccination.
There are currently four COVID-19 vaccines authorized for use in the United States: Pfizer-BioNTech, Moderna, Novavax, and Johnson & Johnson Janssen (only to be used in certain circumstances due to safety concerns). Side effects will vary from person to person after receiving the vaccine. Commonly reported side effects include:
- Redness and swelling at the site of the shot
- Muscle pain
While rare, there have been reported cases of developing myocarditis, which is inflammation of the heart muscle, and pericarditis, which is an inflammation of the heart's outer lining. This was found in adolescents and young adult males within several days after receiving the Pfizer and Moderna mRNA COVID-19 vaccines. This occurred more frequently after the second dose of the vaccine.
How exercise affects the heart
Routine exercise has shown health benefits with a decreased risk of developing heart disorders. With persistent, high-intensity exercise, the heart structure changes to allow for better blood and oxygen flow to and from your heart. This allows your heart to keep up with the demands of your body. These changes are specific to the type of exercise you are doing or the sport you are participating in. Therefore, many high-performance athletes have a slower resting heart rate and can recover from their exercise faster than the average person. In the majority of athletes, these changes cause no harm to their hearts. Exercise has shown positive effects on the body, such as better blood pressure control, improved cholesterol, and better control of blood sugars, which all lead to a decreased risk of developing heart disorders.
Studies have shown that the remodeling of the heart due to high-intensity exercise may contribute to an increased risk of developing an abnormal heart rate and rhythm that can cause the heart to stop. However, there is insufficient evidence to support these claims.
Health screening and evaluation process
There has been an ongoing debate on what health screenings are needed for professional athletes. Many cardiac conditions that cause sudden cardiac death may present with no symptoms. Identifying cardiac conditions that increase the risk of sudden cardiac arrest can prevent it from occurring in the future.
The American Heart Association has created guidelines for a pre-participation evaluation (PPE) that is recommended for athletes before competing. This consists of a 14-point history and physical and electrocardiography (ECG). An ECG shows the heart rate and rhythm and can detect any abnormal heart rhythms that can be dangerous to the heart. Due to the limitations of the ECG, there has been debate on its benefit when used in screening athletes for cardiac disorders. At this time, it is recommended to leave that decision up to the physician examining the athlete.
Professional sports across the world also initially added additional testing upon return to play after acquiring the COVID-19 virus. The return-to-play testing aligns with the American College of Cardiology recommendations and assesses the prevalence of detectable inflammatory heart disease in professional athletes with prior COVID-19 infections. Screenings in this program include drawing troponin levels and getting an ECG and echocardiography. Troponin is a protein found in your heart muscle that isn’t normally found in your blood. If troponin is found in your blood, it means that your heart has been injured or damaged. An echocardiography is an ultrasound of the heart. This takes pictures of the heart and allows a cardiologist to look at the inside of the heart, including the heart valves, and check for any abnormalities.
While the risk of an athlete suffering a sudden cardiac event is low, there is still a risk of this occurring. Most cases are related to an undiagnosed underlying heart condition. If there is a family history of a heart disorder, athletes can consider routine heart screening to identify any heart conditions before a sudden cardiac arrest occurs. The COVID-19 virus and mRNA vaccine also present a risk of adverse heart effects. High-performance athletes should consider additional monitoring after being ill with COVID-19 and follow the American College of Cardiology guidelines to return to play.
Existing data is limited to showing the effects of the COVID-19 virus on a high-performance athlete's heart. Studies suggest that there is a high percentage of patients who experienced ongoing myocarditis after COVID-19 infection. Ongoing analysis of data specific to athletes is needed to determine more specific guidelines of return to play after a COVID-19 infection.
If an athlete has concerns about how the mRNA COVID-19 vaccine could affect their heart, they should follow up with their healthcare provider regarding their concerns. Data cannot currently link the mRNA COVID-19 vaccine to cardiac disorders in athletes.
Keeping an AED on the sidelines and having professionals trained in CPR has decreased the risk of death when an athlete suffers a sudden cardiac arrest. Exercise decreases the risk of developing heart disease. Athletes should continue to follow their training programs to continue enjoying their chosen sport.
- British Journal of Sports Medicine. AMSSM Position Statement on Cardiovascular Preparticipation Screening in Athletes: Current evidence, knowledge gaps, recommendations and future directions.
- Methodist DeBakey Cardiac Journal. Sudden Cardiac Death in Athletes.
- Circulation. Can Intensive Exercise Harm the Heart?
- JAMA Cardiology. Prevalence of Inflammatory Heart Disease Among Professional Athletes With Prior COVID-19 Infection Who Received Systematic Return-to-Play Cardiac Screening.
- CDC. COVID-19.
- JAMA Cardiology. Coronavirus Disease 2019 and the Athletic Heart.
- JAMA Cardiology. Outcomes of Cardiovascular Magnetic Resonance Imaging in Patients Recently Recovered From Coronavirus Disease 2019 (COVID-19).
- The British Medical Journal. SARS-CoV-2 vaccination and myocarditis or myopericarditis: population based cohort study.