Measuring Athlete's Risk of Cardiovascular events

Although regular physical activity is the cornerstone of every effort to
prevent cardiovascular events, (vigorous) exercise is associated with a
transiently increased risk of acute cardiac events, particularly in untrained
persons. More than 90% of acute exercise related cardiac events occur in men,
predominantly those aged 45 years or over. Acute events in young athletes (aged
35 years or younger) are mainly caused by inherited cardiac diseases, whereas
events in older athletes are largely caused by coronary artery disease. Despite
the rare occurrence of cardiac events in young athletes (approx. 1 per 100.000
athletes per year) the study group of sport cardiology of the European Society
of Cardiology (ESC) recommends mandatory pre-participation screening of
athletes aged 35 years or younger. Intuitively, it would make more sense to
direct screening efforts at older athletes as they have a higher risk of acute
cardiac events. Effectively this would imply screening for the presence of
coronary artery disease in (largely) asymptomatic athletes to identify those at
a high risk of cardiovascular events. Minimally invasive cardiac imaging is
likely to play an important role in this group.

Primary objective:
- To assess the prevalence and severity of coronary artery disease in
asymptomatic older (> 45 years) men who undergo exercise testing as part of a
sports medical evaluation, with minimally invasive cardiac multidetector
computed tomography (MDCT) imaging (determining the Agatston score, total
coronary atherosclerotic burden and the presence of coronary artery disease -
defined as luminal narrowing of at least 50%), irrespective of future
cardiovascular disease (CVD) risk as estimated with SCORE and the results of
the exercise test.
Secondary objectives:
- To determine the relation between conventional CV risk factors and coronary
artery disease (CAD) in this group.
- To determine the relation between lifetime physical activity and CAD in this
group.

The MARC study will be a cross-sectional diagnostic study of 300 asymptomatic
men aged 45 years or older undergoing exercise testing as part of a sports
medical work-up at Meander Medical Center, Amersfoort, who will be invited to
undergo minimally invasive cardiac MDCT imaging. The cardiac MDCT results,
combined with the conventional CV risk profile, will be used to provide the
participants with a tailored cardiovascular advice, based on the prevailing
Dutch guidelines and participants will be followed up for an additional five
years to determine the occurance of hard cardiovascular end-points.

For a detailed review of the potential risks, i.e. risks associated with
cardiac MDCT, refer to page 12 of the protocol. In brief:
• Adverse reaction to the contrast medium (nausea, skin hives in 1 to 3% of
participants, fatal adverse reactions in 0.001%)
• Contrast medium-induced renal insufficiency
• Cancer due to exposure to ionizing radiation (estimated to equal 1 year of
background radiation)
• Accidental findings in the scan field may lead to additional diagnostic tests
with extra costs and risks not covered by this study.
• Administration of sublingual nitroglycerin prior to CT scanning may cause
transient sensations of headache and flushing.
• Administration of metoprolol to lower heart rate prior to CT scanning may
cause transient sensations of headache and dizziness. It is expected that only
a minority of participants will receive metoprolol to lower heart rate below 70
beats/minute.