The rate of sudden cardiac death in young athletes is higher than previous estimates - but the problem is still relatively rare, according to the results of a 27-year registry reported in Circulation: Journal of the American Heart Association.

These data add to the debate about whether the United States should implement a broad and mandatory screening program for young athletes to receive an electrocardiogram (ECG) before playing sports. The American Heart Association currently recommends a physical exam and family history questionnaire as a first-line screening, with further examination based on the results of those initial steps.
In contrast, the European Society of Cardiology and the International Olympic Committee promote the use of routine ECGs for athletic pre-participation screening. Italian athletes have a rigorous pre-screening program.

"Sudden deaths in young competitive athletes are highly visible and tragic events with a huge impact on the community," said Barry Maron, M.D., lead author of the report and director of the Hypertrophic Cardiomyopathy Center at the Minneapolis Heart Institute Foundation, Minn. "However, the magnitude of this problem as a public health issue is controversial. We set out to assemble data that would put the issue into a more realistic context."

The researchers created a large registry that included 1,866 athletes in 38 different sports who died suddenly or survived cardiac arrest throughout the United States from 1980 to 2006. The athletes ranged in age from 8 to 39 years old. Of the deaths:

• 56 percent (1,049) were due to cardiovascular disease. Hypertrophic cardiomyopathy was the most frequent cardiovascular cause of death, accounting for about one-third of these deaths.
• 22 percent (416) were due to blunt trauma causing structural damage to the heart.
• 4 percent (65) were due to commotio cordis.
• 2 percent (46) were due to heat stroke.

Among the 1,049 deaths due to cardiovascular disease, the highest number of events in a single year was 76, with an average of 66 events per year over the last six years; 30 percent of the cardiovascular abnormalities would not be expected to be reliably identified by preparticipation screening, even with ECG, Maron said.

The authors note that the absolute number of all sudden deaths reported is significantly less than deaths associated with many other risks for this age group -cancer, leukemia, cystic fibrosis, automobile fatalities and homicides, as well as accidental electrical fatalities, meningitis deaths and phenylketonuria diagnoses - and were similar to the rate of lightning-related fatalities.

Maron said they focused on the most recent six years of the study because reporting methods in recent years are more robust. The researchers found the frequency of sudden deaths at about 0.6 deaths per 100,000 person-years -a rate similar to the 0.87 per 100,000 person-years reported for competitive athletes from the Veneto region of Italy over a recent 11-year period. In Italy, a 12-lead ECG is a mandatory part of athletic pre-screening.

"Indeed, the relatively low absolute number of cardiovascular sudden death events reported here in young athletes raises some doubt regarding the ambitious considerations for pre-participation screening based on the rigorous Italian model," Maron said in the report.

Nevertheless, he said, even the small risks of athletic training and competition support continued efforts at obtaining adequate pre-participation screening under the current guidelines, and highlight the importance of disqualification standards.

"The low overall event rate reported here should provide a general measure of reassurance regarding sports participation, but underscores the need for mandatory reporting of sudden deaths in young athletes," Maron said.

Co-authors are: Joseph J. Doerer, B.S.; Tammy S. Haas, R.N.; David M. Tierney, M.D.; and Frederick O. Mueller, Ph.D. Author disclosures are available on the manuscript.

The national Operating Committee on Standards for Athletic Equipment in Chapel Hill, N.C. and the William Randolph Hearst Foundation in San Francisco, Calif. funded the study.