Another story of a probable case of commotio cordis –  this one occurring during a softball game.

Sad situation, especially since patients often die when the injury occurs. When CPR is started by trained professionals within 3 minutes, only about 25% of patients survive. If resuscitation is delayed more than 3 minutes, more than 97% of patients die. There have only been about 250 cases of commotio cordis reported to the national registry, most occurring during baseball games, but it is likely that the cases are underreported. More than 97% of victims are male and the mean age of victims is 15 years.

The cause of commotio cordis is related to the timing of the impact to the chest, not to the force of the impact. Impact during a 15 ms interval at the beginning of cardiac repolarization (about 1% of the total cycle of a complete heartbeat) reliably causes ventricular fibrillation. [Crawford’s Cardiology, 3rd edition]. Projectiles don’t have to be traveling at a high rate of speed in order for commotio cordis to occur. Baseballs and lacrosse balls traveling 40 mph were able to cause ventricular fibrillation in up to 50% of cases – even when chest protectors were used.

However, the firmness of the object causing the impact does affect the incidence of cardiac arrhythmias. Commotio cordis tends not to occur with air-filled projectiles such as tennis balls or basketballs, but rather occurs in sports with solid playing objects such as baseball, hockey, and lacrosse. [Netter’s Cardiology, 2nd edition] It has also been reported in football hits, karate strikes, and in one instance where a dad punched his infant child in the chest because he wouldn’t stop crying.

The best chance at survival occurs when CPR is started within one minute of the injury and when rapid defibrillation occurs. That’s where AEDs come into play. If you see someone drop after getting hit during a sports event, performing rapid chest compressions without mouth-to-mouth (to the beat of “Staying Alive” by the Bee Gees) and using an Automated External Defibrillator as soon as possible may just save that person’s life.

Of course, if you don’t resuscitate someone from what likely to be a fatal condition, there are always lawyers willing to penalize you for doing something “wrong.”

This entry was posted on Tuesday, August 9th, 2011 at 5:55 am and is filed under Medical Topics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.