Even with criteria modified for athletes, National Basketball Association (NBA) players are more likely than other athlete groups to have abnormal electrocardiographic (ECG) findings, according to a report in JAMA Cardiology.

Among 519 NBA athletes, 81 players (15.6 percent) had results classified as abnormal under international criteria developed in 2017. Using Seattle and refined interpretation criteria—two earlier iterations of athlete-specific criteria—ECG abnormalities were present in 25.2 and 20.8 percent of study participants, respectively.

“A limitation of these criteria is that they are not sport-specific, so they cannot encapsulate how the wide variations in hemodynamic demands of different sports and the varied baseline characteristics of athletes engaged in these sports might affect the ECG results,” wrote lead author Marc P. Wasse, MD, PhD, with the division of cardiology at Columbia University Medical Center, and colleagues.

“Because basketball is one of the leading sports in the world and elite male basketball players have been shown via echocardiographic findings to develop significant athletic cardiac remodeling, the generation of normative ECG data in this athlete group offers important reference value.”

The researchers studied preseason ECG examinations of NBA athletes who played in the 2013-14 and 2014-15 seasons, plus participants from the 2014 and 2015 NBA predraft combines. All abnormal ECG findings were compared with matched echocardiographic data.

The studied athletes were 78.8 percent black, 18.5 percent white and 2.7 percent other ethnicities/races. Older players and those with increased left ventricular relative wall thickness (RWT) were significantly more likely to have abnormal ECG classifications, the authors reported. Abnormal T-wave inversions (TWI) were present in 6.2 percent of the athletes and associated with smaller left ventricular cavity size and increased RWT.

“We observed a higher prevalence of abnormal ECG findings in NBA players compared with other athlete groups in a wide variety of sports from amateur to professional levels whose ECG findings have been published,” Wasse et al. wrote. “The NBA players in this study were generally older (mean age, 24.8 years; range, 18-39 years) than most athletes included in other published studies of athlete groups, and this fact, combined with the finding of more ECG abnormalities in the oldest group of NBA athletes in the present study, might demonstrate that athlete age and cumulative years of intense training are important factors that influence athletic ECG changes.”

The researchers noted they lacked serial follow-up measures for the athletes and cautioned against applying the findings to participants in other sports or youth basketball players.

In an accompanying editorial, Sanjay Sharma, MD, FRCP, pointed out Wasse et al.’s study is the first time the international guidelines for ECG interpretation in athletes has been assessed in a predominantly black population.

“This study is an important contribution to sports cardiology,” Sharma wrote. “It emphasizes the need for more detailed investigation in larger cohorts of black athletes to ascertain whether assessing the pattern, depth and/or width of inferior/lateral TWI might help predict more precisely which black athletes might be at risk of cardiac disease or death. The association of concentric left ventricular remodeling or hypertrophy with inferior and/or lateral TWI raises the question of whether left ventricular hypertrophy induced by sports in black athletes might be a harbinger for serious arrhythmias, as is the case in black patients with hypertensive heart disease.”

Sharma pointed out sudden cardiac death in the presence of exercise occurs more often in Division I male basketball players (one death per 3,126 student-athletes per year) than in the total population of NCAA student-athletes (one death per 43,770 per year). Like the NBA, Division I basketball is largely composed of black players.

“Until further data are available, it would be prudent to routinely investigate black athletes with inferior and/or lateral TWI for cardiomyopathy,” Sharma wrote.