New guidelines from the American Heart Association and the American College of Cardiology have loosened some restrictions placed on competitive athletes with certain heart conditions.
Cardiologists at Washington University School of Medicine in St. Louis led two of the task forces responsible for updating the guidelines that help doctors decide when it is safe for a heart patient to participate in competitive sports, from high school athletics to Olympic or professional-level competitions.
"We want people to be active, but we also want them to be safe," said cardiologist Alan C. Braverman, MD, the Alumni Endowed Professor in Cardiovascular Diseases in the Department of Medicine, and a co-author of the guidelines. "The good news is sudden death in athletes is thankfully very rare. But there are certain types of cardiovascular diseases associated with that risk. The goal of these guidelines is to help doctors recognize when someone has an increased risk of sudden cardiac death and help change activity levels to lower that risk."
The guidelines recently were published simultaneously in two leading heart journals: Circulation and the Journal of the American College of Cardiology. These recommendations apply to athletes with diagnosed heart conditions who participate in organized sports led by a coach, not recreational sports.
Braverman led the task force revising the guidelines for patients with disorders of the aorta, the large artery that carries blood from the heart to the body. Washington University pediatric cardiologist, George F. Van Hare, MD, the Louis Larrick Ward Professor of Pediatrics, led the task force updating the guidelines for patients with congenital heart disease - defects in the heart that are present at birth.
When a young athlete dies suddenly during play or practice, the cause is often cardiac arrest. Unlike a heart attack, when blood flow to the heart is blocked, in this case the heart stops because an undetected condition causes its electrical signals to misfire.
In general, the new guidelines allow participation for certain patients who would have been heavily restricted by earlier versions of the recommendations. This includes patients with certain heart rhythm disorders such as long QT syndrome and patients with implanted pacemakers. The new guidelines acknowledge that the risk of death in these patients is lower than previously thought.
According to Braverman and Van Hare, the changes come from improved understanding of genetic mutations associated with high-risk heart conditions and better diagnostic and screening techniques. For high-risk patients, such as those with a weakened aorta due to Marfan syndrome or with a thickened heart wall due to a condition called hypertrophic cardiomyopathy, strict restrictions on participation remain in place.
"With exceptions for known high-risk conditions, these guidelines are more lenient than they have been in the past," Van Hare said. "The new recommendations were written in recognition of the fact that physical activity is incredibly important to a person's overall health, and even those with cardiovascular disease will benefit. The shift also recognizes the rarity of adverse events for patients with congenital heart disease."
"While it is important to restrict some patients with specific conditions, we are encouraging the vast majority of our patients to avoid a sedentary lifestyle," Van Hare added. "And that's really new. That hasn't been in prior sets of recommendations."
Braverman, who treats patients with Marfan syndrome and other conditions associated with an enlarged aorta, said the new guidelines will help doctors decide whether patients whose aortas are on the borderline of being too large are safe to participate in sports. Enlarged aortas can be a sign of an underlying disease and with intense physical exertion can be at increased risk of a life-threatening rupture or dissection.
"For patients with aortas that are clearly dilated, that's a red flag for avoiding high-intensity sports," Braverman said. "But there are healthy people out there, especially people who are very tall, whose aortic measurements are just above the normal range. In the past, we would have restricted these athletes from competing. Now we can perform genetic testing to evaluate for Marfan syndrome and other high-risk genetic conditions. We also have better techniques for measuring the aorta. In the appropriate setting, we will follow these apparently normal patients to ensure the aorta is not changing, and these athletes can continue to compete in their sports."
And even those patients with restrictions may not be excluded from sports entirely. The guidelines also classify sports according to how they place loads on the heart muscle. Weightlifting, for example, causes a large increase in blood pressure. Long-distance running, in contrast, increases the volume of blood the heart pumps. With many activities that fall between these extremes, doctors can help patients choose sports that are safe for them, depending on the disorder and the risks involved.