Sudden Cardiac Death in Athletes

It is estimated that 1 to 3 out of 100,000 healthy young athletes suddenly go into cardiac arrest.⁽¹⁾ For a lot of time now, it has remained a problematic medical challenge to figure out how to prevent sudden cardiac death of athletes. Sudden cardiac arrest is the sudden loss of heart activity because of an irregular heart rhythm. While survival is possible, but it is only possible if immediate and appropriate medical assistance is provided. Meanwhile, sudden cardiac death is the unexpected and swift end to all cardiac activity, with the blood flow and breathing stopping right away. Within a matter of seconds, the person loses unconsciousness and dies.

Sudden cardiac death is a rising concern amongst seemingly healthy young adults under the age of 35 years, especially in males and athletes. When sudden cardiac death takes place in athletes, it can be due to a previously undiagnosed heart condition such as congenital heart disease.⁽²⁾ This undetected heart issue might cause any young adult to suddenly die while performing physical activity, such as playing competitive sports. However, in some cases, it is also possible for sudden cardiac death to take place without any physical exertion.

Most athletes, however, are able to compete every year without having any heart-related incidents. Most sudden cardiac sudden deaths are observed in older adults, especially those with a history of heart disease. However, a sudden cardiac arrest has become the leading cause of death in young athletes. While the exact estimates differ, it is believed that 1 in around 50,000 to 1 in 80,000 young athletes die every year due to sudden cardiac death.^{(3, 4)}

Sudden cardiac death in athletes is believed to be caused by a fault in the electrical signaling process of the heart. Having a very fast heartbeat can cause the lower chambers of the heart (known as ventricles) to quiver unnecessarily rather than pumping blood as they should. This irregular heart rhythm is known as ventricular fibrillation.⁽⁵⁾

Any condition that puts a lot of strain on the heart or causes damage to the heart tissue can significantly increase the risk of sudden cardiac death. Some conditions that can cause sudden cardiac death in athletes are as follows:

• Disorders in Heart Rhythm: Long QT syndrome is a type of condition related to the heart rhythm that causes chaotic and fast heartbeats. It is usually believed to be the reason behind unexplained fainting and sudden cardiac death, especially in young athletes. Long QT syndrome might be present at birth, a condition known as congenital long QT syndrome, or it may be caused by an underlying medical condition or even by certain medications. This is known as acquired long QT syndrome.^{(6, 7, 8)} There can be some other types of heart rhythm disorders as well that cause sudden cardiac death, such as the Wolfe-Parkinson-White syndrome and the Brugada syndrome.
• Hypertrophic Cardiomyopathy: This condition causes thickening of the heart muscle, and it is known as being one of the most common causes of sudden cardiac death in athletes. This is a genetic condition that causes the heart muscle to grow and become too thick, which makes it difficult for the heart to pump blood. This also causes your heartbeat to speed up drastically, especially when under stress.^{(9, 10)}
• Blunt Chest Injury: Taking a hard hit directly to the chest can also be a cause of sudden cardiac death. This is known as commotio cordis. Commotio cordis tends to occur in athletes who get hit very hard right in the chest by another player or sports equipment. However, this condition does not cause damage to the heart muscle. Instead, this changes the electrical signaling of the heart. The blow right to the chest can lead to ventricular fibrillation, especially if it strikes at a particular time in the signaling cycle.^{(11, 12, 13)}
• Congenital Heart Defect: This is a problem in the heart structure that is present at birth. Some people are just born with certain changes in the heart and blood vessels that can decrease the blood flow and also cause sudden cardiac death.^{(14, 15)}

Many times sudden cardiac death takes place without any prior warning. And it is also possible that when the warning signs do occur, they simply go unrecognized. It is essential for parents, coaches, and others involved in the life and career of an athlete to take note and schedule a health checkup for anyone who experiences the following:

• Shortness of Breath Or Sudden Chest Pain: These symptoms could also be a sign of a heart problem. However, these symptoms could also be an indication of asthma, so it is important to undergo a thorough health checkup.
• Unexplained Fainting (Known As Syncope): Fainting that happens unexpectedly during exercise or any activity could be an indication of an underlying heart problem.
• Family History Of Sudden Cardiac Death: If there is a history of sudden cardiac death in the family, it makes a person more susceptible to also having the same type of heart problem. It is also essential to talk to your doctor about screening options if there is a history of unexplained and sudden deaths in your family.

It can sometimes be possible to prevent sudden cardiac death in athletes. The fact is that if you are already aware that you are at a high risk of sudden cardiac death, your doctor is likely to recommend that you avoid taking part in competitive or contact sports.

Depending on what the underlying condition is, surgery or medication may help in reducing the risk of sudden death. In some cases, a medical device known as an implantable cardioverter-defibrillator (ICD) might have to be implanted in the chest to keep on monitoring the heart’s rhythm. In case a life-threatening heart rhythm issue occurs, the ICD will send electrical shocks that will reset the heart.^{(16, 17)}

Many athletic training centers have a device known as an automated external defibrillator (AED) that is always kept at hand and available to use.^{(18, 19)} An AED is a portable medical device that is used to treat someone in cardiac arrest. This device sends a shock to reset the heart.

If you are at risk of sudden cardiac death, you should always let your doctor know about any kind of sports or physical activity you are thinking of doing. Whether you can safely take part in sports or even exercise depends on your individual condition. For example, you should avoid playing full contact sports if you have any type of medical device implanted in your chest for detecting and stopping irregular heartbeats. A direct blow to the chest in contact sports may cause the device to move.

Your doctor will be the best person to tell you about which types of exercise and sports are safe for you.

References: