NEW YORK (Reuters Health) - A blow to the chest of a young athlete from a ball, or hockey stick, or hard collision with another player, can trigger an irregular heartbeat that leads to sudden death -- and commercially available chest protectors don't do what they're supposed to do, according to a new report.

"A significant proportion (about 40 percent) of sudden deaths reported in young competitive athletes due to blunt chest blows occur despite the presence of commercially available sports equipment generally perceived as protective," Dr. Barry J. Maron of the Minneapolis Heart Institute Foundation, Minnesota, and colleagues report in the American Journal of Cardiology.

The team reviewed 182 instances of a deadly irregular heartbeat, called commotio cordis, triggered by blows to the chest and found that 85 of the deaths occurred during practice or competition in organized sports.

For 32 of these 85 young competitive athletes (38 percent), the chest blows proved fatal even though they were wearing a standard chest protector made of polymer foam covered by fabric or hard shells -- devices believed to be capable of protecting the chest from injuries incurred by direct blows, the investigators note.

In 25 of the deaths, the padding on the chest protector did not cover a particularly vulnerable part of the chest at the time of impact. In seven deaths, the projectiles hit the chest protector head-on.

Twenty of these tragic events occurred during high school or middle school sports, five in college sports, four in professional sports, and three others in youth sports.

The athletes who suffered fatal blunt chest blows were all male and between 5 and 23 years of age; their average age was 15. Thirteen were hockey players (including one goalie), ten were football players, six were lacrosse players (including three goalies), and three were baseball players (all of them catchers).

Their findings, Maron and colleagues say, support recent laboratory data demonstrating that commercially available chest protectors are "uniformly ineffective" in protecting against a blow likely to trigger irregular heart rhythm.

Clearly, "improvement in the design and composition of chest protectors are necessary to enhance the safety of the athletic field for our youth," they conclude.