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Ask the Expert:

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ John Hayes, M.D.

John Hayes, M.D.
Sees patients at Marshfield Clinic locations in Marshfield and Weston Centers.

​​Question: What causes an athlete to suddenly collapse?​

​One of the most unexpected and tragic events to occur during athletic competition is sudden cardiac arrest, which causes a young athlete to collapse with no warning.

Sudden cardiac arrest is rare, estimated to affect one in 200,000 high school athletes per year.

These cardiac arrests can occur because of trauma or heat stroke, but the majority of cases happen because of underlying cardiovascular disease.

With the intense demands of physical exertion, this disease makes the heart prone to developing a rapid, chaotic rhythm called ventricular fibrillation.

The heart rhythm can be restored to normal and the athlete’s life saved only if it is rapidly recognized and external defibrillation is performed.

Many of the conditions that put athletes at risk can be identified through careful screening at the pre-participation sports physical and, if necessary, further diagnostic testing.

Warning symptoms may include:

  • Chest pain during exertion
  • Shortness of breath
  • Light headedness
  • Fainting spells
  • Sensations of rapid heart beating (palpitations)

Any prospective athlete with these symptoms needs further assessment and testing.

We look for certain, specific cardiac diseases; if they are identified, the student should not participate in competitive athletics.

Many of these conditions are hereditary, so parents should be aware of their family history regarding heart disease, especially if any relatives have died suddenly and at a young age.

When an athlete goes down, it obviously requires immediate attention.

Cardio-pulmonary resuscitation (CPR) must be started without delay and an automatic external defibrillator (AED) applied as soon as possible.

Communities should strive to have AEDs available at all athletic events for just such an emergency.

Activating the 911 emergency response system is also critical, but the time it takes for responders to arrive may be too long.

While sudden cardiac arrest is rare, we need to be prepared to deal with it. Seeing a young person survive this potential tragedy is one of the most heroic events to occur in sports or medicine.

Marshfield Clinic provides heart care​ in a number of our centers. Your primary care doctor can refer you to the appropriate specialty and location. ​