In the Journals

ECG abnormalities common in NBA athletes

In a new study, 1 in 5 National Basketball Association athletes had abnormal ECG classifications, some of which may be influenced by left ventricular concentric remodeling.

Marc P. Waase, MD, PhD, electrophysiology fellow at NewYork-Presbyterian Hospital, and colleagues analyzed preseason ECG examinations of 519 NBA athletes. The mean age was 25 years and 79% were black. Participants were active-roster (n = 404) or predraft-combine athletes (n = 115). ECGs were performed in the 2013-2014 and 2014-2015 preseasons, in addition to the 2014 and 2015 predraft combine. Three athlete-specific interpretation criteria were used on each ECG: Seattle, refined and international.

Overall, 89% of athletes had at least one physiologic, training-related ECG change, and 63% had two or more changes. An abnormal ECG finding was observed in 25.2% of athletes using the Seattle criteria, 20.8% using the refined criteria and 15.6% using the international criteria.

Athletes aged 27 to 39 years were more likely to have ECG abnormalities compared with those aged 18 to 22 years (22.6% vs. 9.1%; OR = 2.9; 95% CI, 1.6-5.4).

Abnormal T-wave inversions, the most common abnormality in this athlete population, were observed in 6.2% of athletes and were linked to increased LV relative wall thickness and smaller LV cavity size. Athletes in the lowest LV relative wall thickness tertile were less likely to have abnormal T-wave inversions vs. those in the highest tertile (0.6% vs. 14.7%; OR = 29.5; 95% CI, 3.9-221).

“Continued work is required to understand the precise importance of the higher prevalence of repolarization abnormalities in this elite athlete population,” Waase and colleagues wrote in JAMA Cardiology.

Sanjay Sharma, MD, FRCP, professor of cardiology and lead for the inherited cardiomyopathies and sports cardiology unit at St. George’s, University of London, discussed the implications of these findings in a related editorial.

“The association of concentric left ventricular remodeling or hypertrophy with inferior and/or lateral [T-wave inversion] 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 wrote. “This point is pertinent because exercise-associated sudden cardiac death is much more common in (predominantly black) Division I male basketball players (who experienced one such death per 3,126 student-athletes per year) than in National College Athletic Association athletes overall (who had one sudden cardiac death per 43,770 student-athletes per year).” – by Darlene Dobkowski

Disclosures: Waase and Sharma report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.

In a new study, 1 in 5 National Basketball Association athletes had abnormal ECG classifications, some of which may be influenced by left ventricular concentric remodeling.

Marc P. Waase, MD, PhD, electrophysiology fellow at NewYork-Presbyterian Hospital, and colleagues analyzed preseason ECG examinations of 519 NBA athletes. The mean age was 25 years and 79% were black. Participants were active-roster (n = 404) or predraft-combine athletes (n = 115). ECGs were performed in the 2013-2014 and 2014-2015 preseasons, in addition to the 2014 and 2015 predraft combine. Three athlete-specific interpretation criteria were used on each ECG: Seattle, refined and international.

Overall, 89% of athletes had at least one physiologic, training-related ECG change, and 63% had two or more changes. An abnormal ECG finding was observed in 25.2% of athletes using the Seattle criteria, 20.8% using the refined criteria and 15.6% using the international criteria.

Athletes aged 27 to 39 years were more likely to have ECG abnormalities compared with those aged 18 to 22 years (22.6% vs. 9.1%; OR = 2.9; 95% CI, 1.6-5.4).

Abnormal T-wave inversions, the most common abnormality in this athlete population, were observed in 6.2% of athletes and were linked to increased LV relative wall thickness and smaller LV cavity size. Athletes in the lowest LV relative wall thickness tertile were less likely to have abnormal T-wave inversions vs. those in the highest tertile (0.6% vs. 14.7%; OR = 29.5; 95% CI, 3.9-221).

“Continued work is required to understand the precise importance of the higher prevalence of repolarization abnormalities in this elite athlete population,” Waase and colleagues wrote in JAMA Cardiology.

Sanjay Sharma, MD, FRCP, professor of cardiology and lead for the inherited cardiomyopathies and sports cardiology unit at St. George’s, University of London, discussed the implications of these findings in a related editorial.

“The association of concentric left ventricular remodeling or hypertrophy with inferior and/or lateral [T-wave inversion] 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 wrote. “This point is pertinent because exercise-associated sudden cardiac death is much more common in (predominantly black) Division I male basketball players (who experienced one such death per 3,126 student-athletes per year) than in National College Athletic Association athletes overall (who had one sudden cardiac death per 43,770 student-athletes per year).” – by Darlene Dobkowski

Disclosures: Waase and Sharma report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.

    Perspective

    John P. Higgins

    The findings add that physiologic ECG changes are common in NBA athletes (89%) and higher than in other studied athlete groups. Most NBA players are African-American, and this ethnicity has been associated in the past with larger cardiac dimensions than either Caucasian or West Asian ethnicity (Riding NR, et al. Br J Sports Med. 2017;doi:10.1136/bjsports-2012-091258). Yet, of note, the most common abnormality, T-wave inversion, did not relate to age, height, body surface area, ethnicity LV mass; it was more prevalent in athletes with the smallest LV cavity size and the highest LV relative wall thickness.
    While the newer 2017 international athlete-specific interpretation criteria (16%) are better than Seattle criteria (25% abnormal), there is still more progress to be made in the criteria. Those who are older (aged 27-39 years) were more likely to have abnormal ECGs. With excessive training, the physiologic development of LV concentric remodeling occurs, and this is the likely reason for the high prevalence of abnormal ECGs in this NBA athlete group.     
    Endurance training is associated with a mild to moderate dilatation of the LV combined with a mild to moderate increase in LV wall thickness, whereas strength training causes an increase in LV wall thickness. The NBA athlete may have both of these effects, as they are doing both endurance and strength training.
    Professional basketball players will often have ventricular remodeling that leads to abnormal ECG. After having an echocardiogram, the physiologic hypertrophy and ventricular remodeling can be correctly diagnosed. Given that the ECG abnormalities increase with age, it is likely that cumulative volume of intense training over the years may contribute to high prevalence in the older NBA players.
    In addition to T-wave inversion, left atrial enlargement (13%), right atrial enlargement (9%), long QT interval (5%) and right bundle branch block (5%) were other common findings noted.
    Future research should include prospective studies following teens with ECGs and echocardiograms and uncover the natural history of the physiological changes and the factors most important in influencing them over time.
    Can a model that incorporates both the ECG and echocardiogram information be the best screening tool to differentiate athletic physiologic changes/remodeling from true cardiac abnormalities?
    While ECG changes are noted commonly in NBA players, most have excellent CV health and a low risk of sudden cardiac death. It is important to be aware of normal variants on their ECGs that can appear abnormal to the untrained physician or ECG automatic interpretation algorithm.

    • John P. Higgins, MD, MBA
    • Sports Cardiologist
      McGovern Medical School
      UTHealth, Houston

    Disclosures: Higgins reports no relevant financial disclosures.