ECG screening in athletes

In the lead article of the December issue of the Journal of Sports Medicine, U of T professor Roy Shephard weighs the importance of electrocardiogram screening against the costs of mandatory implementation.

An electrocardiogram measures the electric activity of the heart. European cardiologists argue that mandatory ECG testing of athletes leads to a significant decrease in sudden cardiovascular deaths triggered by exercise. SCDs occur when the heart suddenly stops beating, usually because of a underlying genetic condition.

North American cardiologists do not agree that ECG screening should be mandatory—they insist that ECG screening does not meet the World Health Organization guidelines for a successful screening program. The WHO stresses that a successful screening program must test for what is prevalent in the population. They also specify that the screening test used must be sensitive and specific. Finally, the screening must benefit the patient more than it negatively affects them.

In his article, Shephard outlines the reasoning behind the proposed mandatory ECG screening. Italian researchers and cardiologists found a sharp decrease in the number of SCDs after Italy implemented a mandatory screening program for its athletes. The rate dropped from 3.6 deaths per 100,000 athletes in the year before mandatory screening to 0.4 deaths afterwards.

Shephard provides an alternative explanation for the drop: it could have occurred as a result of changes in the environment, better control of doping, the availability of emergency services, or random year-to-year variations. Also, in North America, where screening rarely occurs, the rate of SCDs is already only 0.5 deaths per 100,000 athletes.

Shephard also argues that ECG testing only correctly diagnoses SCD-vulnerable athletes 51–70% of the time. Moreover, even if the screening did work perfectly, SCD doesn’t occur frequently enough to have a huge impact on the population; Shephard estimates that on average only one or two adult athletes per 100,000 will die of SCD each year.

As he writes, “ECG screening seems inappropriate, and efforts in preventative medicine would be better directed to more common causes of premature death in the young adult.” These more frequent causes of death in youth include suicides, car accidents, and sports injuries.

Mandatory ECG screening may also discourage high-risk athletes from participating competitively in sports. However, countless studies have shown that there is little health benefit in prohibiting an athlete with abnormal ECG results from participating in sports. A study done in Veneto, Italy showed that 791 athletes needed to be disqualified from competing in sports in order to save one person from SCD.

Another Italian study showed that Italian sports doctors discouraged two percent of athletes from playing sports because of their results from an ECG screening, but these doctors admitted that at most only 0.2% of the athletes had conditions that could lead to SCD. Meanwhile, the other 1.8% could be negatively affected by the lack of exercise and practice.

Even if there were good reasons for implementing mandatory ECG screening, it would pose a huge problem for the medical system in the U.S. and Canada. In the U.S. up to 10 million athletes could require ECG screening, which would cost $2 billion annually. It would also be difficult to find enough medical professionals qualified to interpret ECG results and to perform secondary testing to eliminate false positives.

Shephard concluded that in order to develop a more successful screening program, doctors would need to narrow down the number of athletes that required ECG testing. He suggests only testing athletes with a family history of SCD.