Commotio cordis occurs when a person is hit in the chest and that impact triggers a dramatic change in the rhythm of their heart.

The blow could come from an object, such as a baseball or hockey puck, and may not seem especially serious in the moment. However, commotio cordis is often fatal.

Commotio cordis is an uncommon injury, and it most commonly affects male teen athletes. Without immediate treatment, this condition can cause unexpected cardiac death.

Immediate first aid treatment with CPR and defibrillation with an automated external defibrillator (AED) may be able to restore the heart’s healthy rhythm and save a life.

After being hit in the chest, a person with commotio cordis may stumble forward and lose consciousness. The injury won’t cause any outward trauma to the chest. There may not be a bruise or any indication of a serious blow.

You may not be able to detect a pulse following the injury, because a person with commotio cordis may stop breathing. The injury may cause the heart to stop pumping blood effectively. This leads to decreased perfusion (blood flow) to the extremities and organs such as the lungs, which is why their breathing may stop.

Just getting hit in the chest isn’t enough to cause commotio cordis. The blow must take place at a precise moment during a heartbeat and strike an area near the center of the heart’s left ventricle. The left ventricle is the lower left chamber of the heart.

This blow can trigger ventricular tachycardia, which refers to an abnormally fast beating of the heart in the lower chambers. This is a serious condition. If the same type of contact to the chest takes place a moment later or an inch to one side, it may be harmless.

Some of the main causes of commotio cordis include being hit by a:

  • baseball
  • hockey puck
  • lacrosse ball
  • softball

Playing any sport where you’re at risk for blunt trauma to the chest increases your chances of commotio cordis. Some of the sports that are most likely to result in commotio cordis include:

  • baseball
  • cricket
  • hockey
  • lacrosse
  • softball

People who engage in full-contact martial arts are also at higher risk.

Diagnosed cases of commotio cordis are unusual. In the United States, fewer than 30 events are reported each year. More cases may occur annually but aren’t reported as commotio cordis due to poor public understanding of the condition.

This condition is most commonly seen in boys between the ages of 8 and 18. One reason why commotio cordis may be more common in younger people is that their chest walls are less developed.

If you suspect commotio cordis, fast treatment is essential. For every minute that passes after a person loses consciousness, the survival rate drops by 10 percent. To help treat commotio cordis:

  1. Have someone call 911 or your local emergency services, and perform CPR immediately.
  2. If you can’t feel the person’s pulse, use an AED right away. The AED can assess whether the person should receive an electrical shock, and it may even help restore the heart to a healthy rhythm. CPR can be performed while the AED is being used.
  3. Continue CPR and AED use until an ambulance arrives, unless the person has regained consciousness and appears to be stable.

A person with commotio cordis who survives should be hospitalized and observed for a few days, depending on their recovery and overall health. Anti-arrhythmic medications may be administered to help keep the heart in a steady, healthy rhythm.

If the heart is beating normally and there are no other health problems, the person may be released and allowed to resume normal activities. Follow-up appointments with a cardiologist may be recommended so that they can perform periodic checks on the heart’s rhythm and function.

Successful treatment of and recovery from commotio cordis may result in no further heart problems. A person with commotio cordis may, however, need an electrocardiogram (ECG or EKG) to check their heart for any rhythm disturbances and a doctor’s approval before they’re cleared to play sports again.

Continued abnormal heart rhythms (arrhythmias) are rare because commotio cordis typically affects young people with no structural heart issues. If arrhythmias occur, they may require treatment with medication and possibly a pacemaker. People with continued arrhythmias may be advised against contact sports or activities in which chest trauma is possible.

It may be impossible to prevent injuries to the chest in sports or in other circumstances, such as car accidents. However, there are steps that can be taken to reduce complications from commotio cordis, including loss of life.

Some important steps youth teams or leagues can take to combat commotio cordis include:

  • having an athletic trainer present at practices and games
  • making sure an AED is available at all athletic facilities and that coaches and others involved know how to access it easily
  • educating trainers, coaches, parents, and athletes about how to recognize commotio cordis symptoms, perform CPR, and use an AED

Efforts to reduce the likelihood of the chest injury itself include:

  • making sure pads and other protective equipment are worn properly and consistently
  • teaching athletes how to avoid being hit with a ball, puck, or other implement that could cause this injury
  • avoiding strength and weight disparities between athletes whenever possible
  • using safety baseballs and hockey pucks, which are cushioned

Commotio cordis is a dangerous — and rare — condition.

If you have a child playing a sport in which a chest injury is possible, make sure available protective equipment is worn and that the school or league involved has an AED and trained users available at all times.

Fast intervention can save the life of someone experiencing commotio cordis.