A new European study on electrocardiogram screenings in young athletes found the results of such tests are extremely difficult to interpret, even among highly experienced doctors.

The study, published Monday in Circulation: Cardiovascular Quality and Outcomes, tackles a key component of a subject that has generated headlines around the world in recent years. The issue is whether an ECG test, which measures electrical activity of the heart, can help prevent sudden cardiac deaths among young athletes.

In a few places in Europe and also in Israel, routine ECGs are recommended for young athletes, and the tests are also recommended by the European Society of Cardiology, the International Olympic Committee and the Fédération Internationale de Football Association, or FIFA.

In the United States, however, ECG screening is generally not recommended for healthy high school or college athletes on the grounds that too often it sets off false alarms, prompts unneeded follow-up tests and unproven and potentially dangerous therapies, causes some young athletes to quit sports unnecessarily, and hasn’t been proven to save lives.

Last year, the NCAA issued ECG guidelines to colleges, but stopped short of recommending ECG screenings. In 2014, the American Heart Association and the American College of Cardiology came out against mandatory mass ECG screening, but instead, recommended health care professionals use a 14-point checklist to screen for heart disease.

Benjamin Levine, M.D., a sports cardiologist at UT Southwestern Medical Center in Dallas who helped write the AHA/ACC recommendations, said the new study outlines some of the same concerns expressed in the AHA/ACC statement.

“Even in the best of hands, with the most up-to-date criteria, this is an inconsistent test that’s hard to read well,” said Levine. “In our recent randomized pilot study here in North Texas high schools, we saw exactly the same thing they did — extraordinary variability and inconsistency, even among electrophysiologists.”

The European study looked at how cardiologists – four with ECG screening experience in athletes and four without — interpreted ECG results in 400 athletes. The study concluded that interpretation of ECGs in athletes and the resulting cascade of follow-up tests are “highly physician dependent even in experienced hands … emphasizing the need for formal training and standardized diagnostic pathways.”

Part of the problem is that “cardiologists who do not routinely evaluate young athletes are more likely to request a higher frequency of additional investigations than experienced cardiologists,” said the study’s lead author Harshil Dhutia, MRCP, a cardiologist at St. George’s, University of London.

Another challenge, he said, is that “on occasion, the electrical patterns in healthy athletes overlap with the electrical changes observed in patients with cardiovascular disease. This overlap results in a gray zone, which generates the potential for false-positive ECGs at screening.”

He added, “this issue is particularly pertinent in athletes of Afro-Caribbean origin and in athletes participating in endurance sport.”

The bottom line, Dhutia said, is that while experience helps, there’s still a great need for “appropriate training and education of physicians – and potentially accreditation – to potentially minimize variation, regardless of whether ECG analysis is being conducted for screening purposes or for diagnostic purposes.”

If doctors get the training needed to reduce false-positive ECG rates, “more and more sporting organizations are likely to endorse ECG screening to protect their athletes from sudden cardiac death,” Dhutia said. “This may allow for high school athletes and recreational athletes participating in grassroot sports to potentially reap the benefits of ECG screening.”

Levine points out that all young adults – athletes and non-athletes alike – should be guarded against sudden cardiac death. But until screening processes improve and there’s evidence that the tests help and don’t hurt young people not having heart-related symptoms, it’s best to rely on the 14-point exam recommended by AHA and ACC, he said.

“The paper reinforces the AHA and ACC’s final comment that, based on the inconsistency in the test and – even more importantly – the lack of evidence that it saves lives, we have to be very careful before mandating screenings of large populations,” Levine said.

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