Positive exercise testing in athletes: What does that mean?

Sep 02, 2008

Sudden cardiac death (SCD) during sports activity is an uncommon, but catastrophic event. Different efforts to reduce the risk of SCD related to sports have been undertaken. What is the role of the exercise test in this context? What does a positive exercise test mean?

Regular physical activity reduces cardiovascular risk factors and is associated with reduced cardiac mortality and morbidity. However, the risk for triggering cardiac events increases during vigorous physical activity, especially in individuals with underlying coronary artery disease (CAD). Several factors potentially contributing to oxygen depletion of the heart muscle (myocardial ischemia), may be specifically related to a high level of competition, such as release of stress hormones, increased risk for blood clot formation, thermal stress (heat/cold), altitude, dehydration and electrolyte disturbances.

Coronary artery disease is a very uncommon cause of SCD in young athletes, where underlying (most often unknown) inherited cardiovascular abnormalities are dominating causes. But, CAD is by far the most common cause of SCD in athletes >35 years of age. To reduce the incidence of SCD related to sports, the European Society of Cardiology (ESC) has proposed recommendations for cardiac screening of competitive athletes, consisting of family and personal history (including symptoms), physical examination and 12-lead electrocardiogram (ECG). If any abnormality is found during the screening, additional testing, including often a maximal exercise test, are undertaken to rule out/confirm the presence of an underlying cardiovascular abnormality.

In younger athletes (<35 years), an important indication for the exercise test clinically, is the suspicion of underlying cardiac arrhythmias and/or syncope. In athletes with underlying structural heart disease, such as hypertrophic obstructive cardiomyopathy, the exercise test may show a blood pressure drop or arrhythmias, giving important prognostic information.

The main role of the exercise test in athletes, however, is for the evaluation of "master" athletes (>35 years of age) with a high-risk profile. According to the ESC, the regular use of the exercise test in asymptomatic athletes with a low-risk profile for future cardiovascular events, <35 years of age (men) and <45 years of age (women), is not recommended.

But, in competitive athletes >35 years of age and with a high-risk profile for future cardiovascular events, the exercise test is mandatory to rule out/confirm the presence of (silent) underlying ischemic heart disease. For recreational sports/leisure-time activity, the exercise test today is recommended on an individual basis.

Exercise tests do have proven weaknesses, showing both false positive and false negative results, making additional testing necessary, especially in uncertain cases. If CAD is confirmed, athletes should be treated according to established protocols, and evaluated regarding eligibility for future sports competition, according to international recommendations.

To summarize, the exercise test is an important tool, used for:

-- cardiovascular evaluation of athletes with increased risk for underlying coronary artery disease or
-- on clinical suspicion of exercise-related arrhythmia, chest pain or syncope, or
-- risk stratification of athletes with different known cardiac abnormalities
-- A positive exercise test has to be complemented by additional testing, to confirm/ exclude the presence of underlying cardiovascular abnormality
-- When a final diagnosis has been made, the athlete must be treated according to established protocols and evaluated for future athletic eligibility according to existing international (ESC) recommendations

Source: European Society of Cardiology

Explore further: Most people want it, but the UK isn't ready to legalise assisted dying

Related Stories

Charter nears deal for Time Warner Cable

36 minutes ago

Charter Communications Inc. is close to buying Time Warner Cable for about $55 billion, according to two people familiar with the negotiations.

The monopoly of aluminium is broken

2 hours ago

Discovering Majorana's was only the first step, but utilizing it as a quantum bit (qubit) still remains a major challenge. An important step towards this goal has just been taken, as shown by researchers ...

Yik Yak's frat-bro founders shrug off growing pains

2 hours ago

The most popular post of all time on Yik Yak is a dirty joke. Less than 2 years old, the Atlanta-based social network is geared mostly toward college students who access and post unsigned announcements through an app on their ...

Fears for pink iguanas as Galapagos volcano erupts

2 hours ago

A volcano in the Galapagos islands erupted for the first time in more than 30 years Monday, sending streams of lava flowing down its slopes and potentially threatening the world's only colony of pink iguanas.

Recommended for you

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.