A Boston-based researcher has found that prompt CPR and the use of automated external defibrillators (AEDs) can save the lives of young people who suffer sudden cardiac arrest (SCA) due to blunt trauma to the chest. Known as Commotio Cordis, which can occur in children who are struck by a baseball, softball, lacrosse ball, fist or other object, the condition often claims the lives of its victims within a matter of minutes.

Mark Link, M.D., assistant professor of medicine, Tufts University, reported the results of his research today at the 22nd annual scientific sessions of the North American Society of Pacing and Electrophysiology (NASPE).

"It's important to realize that sudden cardiac arrest happens to children as well as older persons," said Link. "Typically, in Commotio Cordis, the SCA occurs during a sporting event, when a child sustains a chest wall blow and collapses. Onlookers often assume the child has simply had the wind knocked out of him or her. But this can be a catastrophic assumption because, in fact, the child may have experienced a potentially fatal event."

Adults attending such sporting events may not realize that the child's heart has stopped and that immediate help is needed. Automated external defibrillators like the Medtronic Physio-Control LIFEPAK(R) 500 AED are designed to sense that the heart is experiencing ventricular fibrillation, a condition that makes the heart unable to pump blood effectively. If ventricular fibrillation is detected, the AED provides a brief, intense pulse of electricity to the heart, delivered through pads that are applied to the chest, to terminate the episode and save the victim's life.

Commotio Cordis is increasingly being reported in youth sports. The condition is triggered by impact that occurs within a 15- to 30-millisecond window during the vulnerable phase of the heart cycle. Young athletes are especially at risk because of the pliability of their chest walls. Despite wearing chest protectors and taking other precautions, children have died from Commotio Cordis while playing baseball, lacrosse, hockey and softball. More than 125 cases have been documented since the formation of the United States Commotio Cordis Registry three years ago, but the true number of deaths is unknown because of underreporting and misclassification.

Link and his colleagues used a swine model of Commotio Cordis to study the effects of AEDs in recognizing and terminating ventricular fibrillation and to determine the necessity of using cardiopulmonary resuscitation (CPR) following defibrillation to ensure survival. The AED recognized ventricular fibrillation 98 percent of the time in the study, and all episodes were successfully terminated using an AED. In those animals where ventricular fibrillation was present for more than four minutes, CPR instituted after defibrillation increased the likelihood of survival from 0 percent to 65 percent.

"Our study demonstrates that AEDs can recognize and terminate fatal arrhythmias in young athletes, and suggests the need for wider availability of AEDs in the community, potentially even in schools and on the playing fields where our young people are participating in sports," said Link. "Furthermore, it should prompt adults who are engaged in supervising youth athletics to recognize the signs of SCA, learn CPR and have an AED readily available."

Victims of SCA generally collapse without warning, do not have a pulse and are not breathing normally. Adults who witness such accidents involving children should immediately call 911, begin CPR promptly and locate the nearest AED. AEDs are not approved for use in children who are younger than eight years old.

Recent studies published in the New England Journal of Medicine proved that persons with minimal training can successfully use simple, portable defibrillation devices in public places to save lives that might otherwise be lost to sudden cardiac arrest. The studies said, however, that the defibrillators must be close at hand and easily available. Many initiatives are underway in the United States to increase the rapid availability of AEDs where people gather, including pending legislation that will fund the purchase of AEDs by schools.