Sudden cardiac death occurs more frequently in young athletes than in
previous estimates, but event rates are still relatively low, a new
study has shown [1]. In the past six years, when reporting has been
the most robust, fewer than 100 athletes in the US have died each
year, according to investigators.

"The low overall event rate reported here should provide a measure of
reassurance regarding sports participation but underscores the need
for mandatory reporting of sudden deaths in young athletes, and it is
also relevant to the question of whether a national screening program
with noninvasive testing should be considered for US athletes," write
lead investigator Dr Barry Maron (Minneapolis Heart Institute
Foundation, MN) and colleagues online February 16, 2009 in
Circulation.

Sudden cardiac death, as the investigators point out, particularly
among young, competitive athletes, are highly visible events that
generate a lot of attention in the media, as well as have a large
impact in the medical and lay communities. Despite the visibility of
these deaths, the magnitude of sudden death in this population is
still unknown, the researchers write.

In this analysis, Maron and colleagues estimated the absolute number
of sudden deaths in US competitive athletes from registry data at the
Minneapolis Heart Institute Foundation.

From 1980 to 2006, 1866 athletes died suddenly in 38 diverse sports.
Of these sudden deaths, 56% were caused by cardiovascular disease,
but 22% also died from blunt trauma causing structural damage, and 3%
from commotio cordis. The most common cardiovascular causes of death
were hypertrophic cardiomyopathy (30%) and congenital coronary artery
anomalies (17%).

On average, there were 66 deaths from cardiovascular causes per year
over the most recent six years. In this period, the incidence of
sudden death was estimated at 0.6/100 000 person-years. Overall,
reports of sudden deaths were less common from 1980 to 1993, with
only 576 reported during this time period, compared with 1290
individuals who died suddenly between 1994 and 2006.

"It is likely that the steady increase in the number of sudden deaths
observed over the 27 years of this registry reflects enhanced public
recognition due to increased media attention and the more robust
search strategies that have become available recently, rather than a
true acceleration in the occurrence of these events," explain the
researchers.

Preparticipation Screening

At present, the American Heart Association (AHA) does not believe it
is practical or financially feasible to support a large-scale
preparticipation screening involving standard 12-lead
electrocardiogram (ECG) testing for cardiovascular abnormalities in
competitive athletes [2].

As reported previously by heartwire, the AHA recommendations contrast
with programs proposed by the European Society of Cardiology (ESC)
and the International Olympic Committee (IOC), which include
combining noninvasive testing, such as a 12-lead ECG, with the
standard history and physical examination. The ESC and IOC
initiatives are based on the long-term Italian experience with a
state-subsidized national screening program. In Italy, all
individuals 12 to 35 years of age participating in organized sports
are required to obtain annual medical clearance by accredited sports-
medicine doctors.

In their paper, Maron and colleagues suggest that the relatively low
absolute number of cardiovascular sudden death events reported in
young athletes raises some doubt regarding the ambitious
considerations for preparticipation cardiovascular screening.
Instead, the investigators call again for a systematic and mandatory
reporting system for sudden cardiac deaths in young competitive
athletes to determine the true absolute number of these events.

In an editorial accompanying the published study [3], Dr Paul
Thompson (Hartford Hospital, CT) writes that athletes deserve better
data and a more thoughtful "consideration of the benefits and
untoward consequences of any recommended screening program." The
Italian results, for example, are from a single center and do not
include a controlled comparison of different screening strategies.
Moreover, there remain questions about whether an asymptomatic
athlete with a cardiac condition detected by screening has the same
prognosis as an athlete with symptoms. A reliable estimate of the
cost of such extensive screening is also unavailable, notes Thompson.

"Experience suggests that when experts disagree, there is a dearth of
reliable data," writes Thompson. "The present data suggest that the
problem, at least in the United States, is not so huge that we must
leap into action."


Maron BJ, Doerer JJ, Haas TS, et al. Sudden deaths in young
competitive athletes. Circulation 2009; 119: 1085-1092. Abstract
Maron BJ, Thompson PD, Ackerman MJ, et al. Recommendations and
considerations related to preparticipation screening for
cardiovascular abnormalities in competitive athletes: 2007 update.
Circulation 2007; 115:1643-455. Abstract
Thompson PD. Preparticipation screening of competitive athletes.
Circulation 2009; 119: 1072-1074.Abstract