Joydeep Ghosh, MD, FACC.
Assistant Professor of Medicine, Maimonides Medical Center, 4802 Tenth
Avenue, Brooklyn, NY 11219, USA.
Address for
correspondence: Joydeep Ghosh, MD, FACC., Assistant Professor of
Medicine, Maimonides Medical Center, 4802 Tenth Avenue, Brooklyn, NY
11219, USA. E-mail: jghosh@maimonidesmed.org
Abstract
Sudden death in athletes is a
rare event but brings with it an impact that goes beyond sport. There
are many causes of sudden death during exercise. While the
responsibility of preventing or treating them lays with us physicians,
preparticipation screening is largely ineffective and impractical.
Definitive, large scale prospective research is required in order to
design the most cost-effective system for screening of athletes. In the
meanwhile rapid access to defibrillators by trained personnel remains
the best possible approach to abort sudden death.
Key Words: sudden
cardiac death; exercise; athletes
With the World Cup in soccer -
arguably the most passionate sporting event of our times - only a few
days away, it is appropriate to look at the lessons we have learned
over the past few years about sudden death in competitive sport.
In 490 BC
Phidippides ran 26.2 miles from Marathon to Athens, delivering the news
of the Greek victory over the Persians (the first 'marathon' in
recorded history), but then immediately collapsed and died. This is
probably the first recorded incident of sudden death of an athlete.
More recently the death of some high-profile athletes have
focused public interest on this infrequent event and current data
reveal that in the United Sates alone, about 100 athletes - ranging
from schoolchildren to professionals - die every year while engaged in
sporting activity
1. In India
accurate data are not available but recently media attention was
focused on a Brazilian soccer player who died while playing for his
adopted club. Across societies around the world athletes are considered
to be the pinnacle of health and given high status; death of a young,
well-trained athlete on the field represents a particularly tragic
event that leads to utter dismay within the family and the community
and often a barrage of negative media attention.
The paradox of
exercise is that while in the long-term it generally attenuates the
risk of sudden cardiac death, the relative risk is actually increased
during the time of exercise and up to 30 minutes following it
2. This is especially so in patients with
hypertrophic cardiomyopathy, congenital anomalous coronary artery
abnormalities, and inherited ion channelopathies like long QT syndrome
and catecholaminergic polymorphic ventricular tachycardia, or
Arrhythmogenic Right Ventricular Cardiomyopathy, and it is no surprise
that patients with these conditions have a risk of sudden death with
sport that is well above normal. Other conditions implicated in sudden
death in athletes include accessory pathways with antegrade conduction
properties, bicuspid aortic valve, myocarditis, ruptured aortic
aneurysm, Marfan syndrome, mitral and tricuspid valve prolapse and
ingestion of stimulants like cocaine and anabolic steroids. In
addition, sudden death on the field can also be caused by certain
activities like trauma to the chest (commotio cordis) or to the neck
(causing asystole from carotid sinus reactivity)
3.
Given the
myriad causes listed above, the question we have to answer is whether
pre-participation screening works. Since the early eighties, Italy has
been in the forefront of efforts to identify athletes perceived to be
at risk and withdraw them from competitive sports, with a
preparticipation screening program based on 12-lead ECG, a family and
personal history and physical examination.
4
Data presented recently
5
reveal a striking decline in mortality in the population studied (12-35
year olds, in the Veneto region) with the incidence of sudden death
declining to one-tenth of what it was at the beginning of the study.
Most of this was attributed to fewer cases of athletes dying from
cardiomyopathies that were detectable on ECG. To the best of my
knowledge, there are no other prospective studies (of any magnitude)
that look at the effect of preparticipation screening in athletes.
Whether the
result of this study is applicable to other countries is of course,
questionable. Northern Italy has an unusually high incidence of ARVD in
its homogenous population, and unless one is dealing with similar
circumstances the results may not be reproducible. In the United States
currently there is no advocacy for routine ECG's, and the diagnostic
tool used most frequently is a detailed history and physical
examination, with particular attention paid to syncope, palpitations,
chest pain or sudden death in the family. ECG, stress testing and
echocardiograms are used only if there is a suspicion of high risk from
the history elicited. Interpretations of 'quick-screen'
echocardiograms, while being effective in diagnosing HCM or ARVC in a
short period of time, may be particularly challenging given the
similarities between "athletes heart" and hypertrophic cardiomyopathy.
With regard to
India and other developing countries, such preparticipation screening
will need an enormous increase in the Government's commitment to public
health given the huge population of people that needs to be screened
and the low incidence of disease that cause sudden death (a notable
exception may be hypertrophic cardiomyopathy, which has been reported
to have an incidence of 1 in 500 in the Western population).
Unfortunately I doubt that this 'high investment, low return' policy
will find many takers in a country like India, though saving even one
young adult or child's life ought to be seen as making an investment in
the future. The other significant problem with screening is identifying
false positives, with the unnecessary psychological burden it places on
athletes and their families
6.
If any kind of screening policy is indeed adopted, we need physicians
who are well-trained to identify the diseases they are seeking, and who
know how to proceed with borderline cases without causing unnecessary
alarm.
If
preparticipation screening is far away in a country like India, the
least we can do is provide external defibrillators in as many athletic
events as possible, and train paramedics to use them properly. In
particular they must be able to recognize cardiac arrest quickly, and
deliver defibrillation promptly. A successful outcome depends primarily
on time to defibrillation, with about a 10% per-minute decrease in
survival
5.
In the
meanwhile, enjoy the World Cup. Strict compliance to FIFA guidelines at
all venues in Germany regarding availability of rapid access
defibrillation will hopefully ensure that no gifted athlete dies
suddenly on the field.
References
1. Zipes DP. The athlete with
cardiovascular disease and an implanted device. ACCEL 2006; 38 (5).
2. Albert CM, Mittelman MA, et al.
Triggering of sudden death from cardiac causes by vigorous exertion.
New Engl Jour of Med 2000; 343: 1355-1361.
3. Crampton DM. Arrhythmias and sudden
death in athletes. New Engl Jour of Med 2001; 344 (7): 535.
4. Pelliccia A, Maron BJ. Preparticipation
cardiovascular evaluation of the competitive athlete: perspectives from
the 30-year Italian experience. Am J Cardiol 1995: 75:827-829.
5. Estes NA, Zipes DP. Cardiosource.com
(rapid news summaries). Sudden death in Athletes. Accessed:
3/15/06.
6. Maron BJ, Zipes DP, et al. 36th Bethesda
Conference eligibility recommendations for competitive athletes with
cardiovascular abnormalities. J Am Coll Cardiol 2005; 45: 1312-1375.
