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athlete’s heart
Eric Prystowsky MD
Director
Clinical Electrophysiology Laboratory
St Vincent Hospital
Indianapolis, IN
Barry Maron MD
Director
Hypertrophic Cardiomyopathy Center
Minneapolis Heart Institute Foundation
Minneapolis, Minnesota
Athlete’s heart
A case history: presentation
Identification
16 year-old boy
History
2 year history of sudden onset and
termination of a regular, rapid palpitation
causing dizziness, occurring at rest
Holter monitoring revealed 1 asymptomatic 6beat run of nonsustained VT at 140 bpm
Echocardiogram and MRI of his heart are
normal
Athlete’s heart
Hypertrophic cardiomyopathy
Cardiovascular diseases in a healthy, young
person who is also an athlete are all
uncommon in the general population.
Most such diseases are complex and often
require sophisticated testing for diagnosis.
The single most common disease causing
sudden death in young athletes (responsible
for 1/3 of all cases) is hypertrophic
cardiomyopathy (HCM).
Athlete’s heart
Congenital coronary anomalies
The second most frequent group of diseases
are the congenital coronary anomalies of
wrong sinus origin.
Of these, the anomalous origin of the left
main coronary from the anterior or right
sinus of Valsava is the most frequent.
This is a surgically correctable condition, and
a high index of suspicion is required in any
young athlete with impaired consciousness
on exertion.
Athlete’s heart
Additional diagnoses
Additional diseases account for no more than
5% of the overall population of sudden
death.
These include aortic valve stenosis,
atherosclerotic coronary disease, dilated
cardiomyopathy, and arrhythmogenic right
ventricular (RV) dysplasia.
A small subset of these athletes at autopsy
are found to have grossly normal hearts on
anatomic and histological examination. This
group of diseases includes the long-QT
syndrome.
Athlete’s heart
Arrhythmogenic RV dysplasia
For > 20 years Italy has instituted a
systematic annual screening program of all
athletes in organized sports, which includes
a 12-lead ECG and echocardiogram if
necessary.
Arrhythmogenic RV dysplasia is the most
common cause of athlete sudden death in
the Veneto region of the country. Screening,
coupled with a genetic substrate, are likely
responsible for the low incidence of HCM as
a cause of sudden death.
Corrado D, et al. N Engl J Med 1998;339:364-9
Athlete’s heart
An Italian cohort
Causes of sudden death in athletes  35 years
in the Veneto region, Italy, 1979-1996 (N=49)
Arrhythmogenic RV dysplasia
Atherosclerotic coronary artery disease
Anomalous origin of coronary artery
Conduction system disease
Mitral valve prolapse
Hypertrophic cardiomyopathy
Other
11
9
6
4
5
1
13
Corrado D, et al. N Engl J Med 1998;339:364-9
Athlete’s heart
Prevalence data
Over a 12-year period in Minnesota, the
prevalence of sudden death in young
athletes (interscholastic sports, grades 912), was 1 per 200 000.
This has become a significant public health
issue, not because of the absolute numbers,
but because of the symbolism of the death
of a young adult who is otherwise the
epitome of perfect health.
The visibility of these events is also
increased substantially by the news media.
Athlete’s heart
The issue of screening
“Anytime you have rare diseases that
constitute a very small proportion of the
population…it's sort of like looking for a
needle in a haystack... But this is part of our
customary practice in the United States and
has been for 50 years…high school and
collegiate athletes have the advantage at
least of attempting to identify abnormalities
that could be injurious.”
Barry Maron MD
Director
Hypertrophic Cardiomyopathy Center
Minneapolis Heart Institute Foundation
Athlete’s heart
The difficulty in screening
A screening system is already in place, but
the diseases in question are difficult to
detect from a history and physical alone.
For example, patients with nonobstructive
HCM may not present with syncope or have
a family history of sudden death. A loud
murmur may not be present on exam.
In addition, a large proportion of colleges
and states (>30%) do not have in place the
questionnaires recommended by the
American Heart Association as guides for
history taking and physical examination.
Athlete’s heart
The results of screening
Due to confidentiality restrictions, the actual
effectiveness of screening interventions in
the United States has not been determined.
The Italian experience demonstrates the
involvement of government in the screening
process.
If funded by government sources, an ideal
screening intervention would include
echocardiograms in addition to 12-lead
ECGs. Newer, handheld 2-dimensional
echocardiographic instruments may be
useful additions to screening programs.
Athlete’s heart
The ECG as screening test
Hypertrophic cardiomyopathy may be
identified by a screening 12-lead ECG.
Coronary anomalies which are difficult to
identify clinically may appear normal on ECG
testing, because of the presence of periodic,
or “burst” ischemia.
Altogether, the ECG is empowered, and a
reasonable compromise based on cost
comparisons.
Athlete’s heart
Screening is not cost-effective
“…it is one of those discussions that truly
pits money against saving lives. Because it
will never, I don't care how you do it, be cost
effective. You said to begin with, 1 in 200
000. My goodness, I don't care if the test
costs a dollar. If the test costs a dollar, it's
not cost effective, according to the current
guidelines.”
Eric Prystowsky MD
Director
Clinical Electrophysiology Laboratory
St Vincent Hospital
Athlete’s heart
Commotio cordis: etiology
This is the phenomenon of a blunt blow to
the chest causing instantaneous sudden
death.
Commotio cordis occurs in the absence of
heart disease, and is a circumstance in which
mechanical energy is immediately converted
to an electrical distortion.
The blow (hockey puck, baseball) is
positioned directly above the heart on the
left side of the chest and is precisely timed
to the vulnerable part of repolarization, 1520 msec prior to the T-wave peak.
Athlete’s heart
Commotio cordis: prevention
Any “chest barrier” used for protection needs
to be compatible with the game in question,
and should be effective in preventing the
transfer of mechanical-electrical energy.
Softer than normal balls may also be an
effective preventive measure.
Experimental models have not yet validated
these possibilities.
An automated external defibrillator (AED), if
present in a public facility (sports stadium,
for example), could certainly be lifesaving in
this situation.
Athlete’s heart
A case history: diagnosis
Differential diagnosis
Wolfe-Parkinson-White syndrome
versus
AV-node reentry
A normal MRI of the heart does not
show fat replacement in the wall of the
RV, and is therefore not consistent with
arrhythmogenic RV dysplasia.
Occasionally, a work-up requires
diagnostic coronary angiography.
Athlete’s heart
A case history: management
Electrophysiologic testing is the diagnostic
procedure of choice, and very likely would be
followed by an ablation procedure if the
diagnosis of paroxysmal supraventricular
tachycardia were confirmed.
Nonsustained VT in this normal heart is not a
risk factor for sudden death and this 16-year
old boy should be able to return to a normal
life in sports.