Cardiologists recommend screening student atheletes for heart defects

CHICAGO (CNN) -- About half of America's high schools districts are doing an inadequate job of checking students for hidden heart problems before they play sports, researchers said Tuesday.

A report in the Journal of the American Medical Association Tuesday urged schools across the United States to do more. About 30 student athletes die suddenly each year from congenital heart malformations.

Researchers who surveyed pre-sports physical check-ups found 20 states either had no guidelines for a physical exam or asked the wrong questions. One state -- Rhode Island -- doesn't require any pre-participation exam.

And in more than half of the states, the exams don't have to be performed by a doctor.

The solution, researchers say, is to implement national standards for the screening of young athletes.

In all, researchers estimated that 40 percent of state high school associations do not properly screen athletes according to American Heart Association guidelines.

An AHA panel recommends that doctors look for heart murmurs, fainting, chest pain and other signs that a heart malformation may exist.

Approximately 5 million high school students play sports each year in the United States from grades 9 through 12.

Medical Correspondent Rhonda Rowland and Reuters contributed to this report.