Since 2006, the National Basketball Association (NBA) has required all players to undergo stress echocardiograms during each preseason. It is the only U.S. professional sports league with such a cardiac program.
In 2013, the NBA began working with Columbia University’s Medical Center to conduct annual health and safety reviews of the echocardiograms. Physicians for each of the league’s 30 teams send the echocardiograms they performed to David J. Engel, MD, a cardiologist at Columbia. Engel accesses the data through a league-wide electronic medical records system, analyzes the information and shares his findings with the NBA.
In JAMA Cardiology earlier this year, Engel and colleagues published results of echocardiograms performed on 526 athletes during the 2013 and 2014 preseason and at the 2014 NBA draft combine. The NBA supported the work as part of a medical services agreement between the NBA and Columbia. The NBA Players Association, the union representing the players, also approved the manuscript for publication.
“The impetus for doing this was not only for the NBA to promote their own player health and safety, but to provide reference for their team physicians who are caring for the players,” Engel told Cardiovascular Business in a telephone interview. “They were getting all these results and not really still knowing if the findings they were seeing were normal or not.”
Engel said the NBA adopted the policy in 2006 after Atlanta Hawks forward Jason Collier died of an abnormally large heart the previous October. He added that previous research found that basketball players have a 30 times higher incidence of sudden cardiac death compared with other athlete groups. In addition, a higher proportion of basketball players have hypertrophic cardiomyopathy, a genetic heart condition where the heart muscle becomes abnormally thick and predisposes individuals to life-threatening arrhythmias.
The incidence of hypertrophic cardiomyopathy is higher in African Americans, according to Engel. Of the athletes in this study, 77.2 percent were African American, 20.3 percent were white, 2.3 percent were Hispanic and 0.2 percent were Asian.
“Hypertrophic cardiomyopathy is the most common cardiac condition causing sports-related sudden cardiac death,” Engel said.
The mean age was 25.7 years old, while the mean height was 6 foot, 6 inches and the mean weight was 223 pounds.
The researchers found that African American athletes had increased left ventricular wall thickness and left ventricular mass compared with white athletes. Further, 27.4 percent of athletes had left ventricular hypertrophy and 1.0 percent had a left ventricular ejection fraction of less than 50 percent. The athletes’ left ventricular cavity sizes were larger than in normal adults, but the size was proportional to an athletes’ body size.
“We have everything scaled to both height and body surface area,” Engel said. “Everything is scaled to their unique height. We haven’t compared positions like a point guard versus a center where the hemodynamic demands are a little bit different. We haven’t broken it down into that level of detail, but everything is correlated to their height and body surface area.”
Engel said this was the largest cardiovascular study of U.S. athletes. He added that almost all of the data on athletes’ hearts come from Italy, where the government mandates cardiovascular screening and testing for athletes who compete at the national or Olympic level. The information is publicly available, too.
“Everything that we know or we talk about the athletes’ heart comes from this group in Italy that has published the studies of their athletes over the last 20 years,” Engel said. “The U.S. doesn’t have these kinds of policies. There is no type of screening like this for U.S. athletes. We’ve typically been comparing our American athletes to Italian soccer players. You can’t always make that extrapolation and know you’re seeing the right things.”
Engel said he wasn’t sure if other professional sports leagues would follow the NBA in requiring stress echocardiograms. The program demands a lot of resources such as time and money. Plus, management and players must agree on the echocardiograms through a collective bargaining process, which may prove difficult.
Still, Engel said the information is now public to anyone who wants access and is potentially helpful to sports medicine physicians and other doctors who treat athletes. The researchers plan on following the athletes throughout their career and after they retire to understand what happens to their heart over time.
“It’s important when you analyze an athlete, there’s a different frame of reference,” Engel said. “What we’ve put out there now will provide people a frame of reference to compare their athletes, whether they’re white or black of 7-foot-1or 6-foot-3. We’ve already gotten a lot of very positive feedback not only from team physicians in the NBA but other sports medicine doctors around the country.”