NEW YORK — The international criteria for electrocardiography (ECG) interpretation in athletes perform better than prior iterations in predominantly African American National Basketball Association (NBA) players, but the false-positive rate is still relatively high in these elite athletes, a new study suggests.[1]
Among 519 NBA players (78.8% African American) with no structural disease on preseason echocardiographic testing, abnormal ECG findings were identified in 25.2% by using the 2013 Seattle criteria, 20.8% by using the 2014 refined criteria, and 15.6% by using the 2017 international criteria.
It’s progress, but “Fifteen percent would still be considered a relatively high false-positive rate when you’re screening particularly large groups of athletes,” study author Dr John DiFiori (the NBA’s director of sports medicine) said in an interview.
Dr Sanjay Sharma (St George’s, University of London, United Kingdom), who coauthored the international criteria and a related editorial,[2] echoed those sentiments in an email to theheart.org | Medscape Cardiology.
“The false positive rate in white athletes is now only 3%, but we still have a way to go with black athletes,” he said. “This is because 6% have inferior T-wave inversion and 4% have lateral T-wave inversion.”
Sharma noted that false-positive rates reached almost 40% in black athletes screened with the 2010 European Society of Cardiology recommendations, which were derived from a group of white, predominantly amateur Italian athletes and considered T-wave inversion (TWI), axis deviation, atrial enlargement, and right ventricular hypertrophy as ECG anomalies that warranted further tests.
Since then, large studies have shown that TWI in the anterior leads (V1 to V4) are normal variants in black athletes and are usually preceded by ST-segment elevation. Other studies have also shown that axis deviation, atrial enlargement, and right ventricular hypertrophy are normal variants in all athletes.
The findings have been incorporated into subsequent ECG interpretation criteria, including the international recommendations, which consider TWI in the anterior leads in black athletes as normal and right ventricular hypertrophy as normal. Axis deviation and atrial enlargement are in the borderline category and are considered abnormal only if they coexist, Sharma said.
None of the ECG interpretation criteria, however, are sport-specific, note the investigators, led by Dr Marc Waase (Columbia University Medical Center, New York, NY). Elite basketball players are known to develop significant athletic cardiac remodeling. Yet the ECG criteria can’t encapsulate how the wide variations in hemodynamic demands of different sports and varied baseline characteristics of the athletes might affect ECG results.
At baseline in the present study, the 519 NBA players had a mean age of 24.8 years (the oldest group was age 27 to 39 years; the youngest group was age 18 to 22 years), a mean height of 199.9 cm, and a mean body surface area of 2.37 m2. White athletes were older than African American athletes and had a higher mean body surface area, while African Americans were more likely to have two or more training-related ECG findings (66% vs 49%), including early repolarization (72.6% vs 58.3%).
The results, published recently in JAMA Cardiology, showed no significant relationship between abnormal ECG findings and race, athlete height, body surface area, or left ventricular (LV) mass or cavity size.
Abnormal ECG findings, however, were significantly more common in the oldest vs the youngest athletes (22.6% vs 9.1%; odds ratio [OR], 2.9; 95% CI, 1.6–5.4) and in those in the highest vs lowest tertile for LV relative wall thickness (RWT) (25.2% vs 9.3%; OR, 3.3; 95% CI, 1.8–6.1).
Abnormal TWIs were present in 6.2% of athletes but did not differ significantly by athlete race, age, height, body surface area, or LV mass.
TWIs increased in prevalence, however, as LV cavity size decreased and RWT increased. The odds of a TWI were 8-fold higher in the lowest than in the highest tertile for LV end-diastolic diameter (11% vs 1.4%; OR, 8.6; 95% CI, 2.0–37.9) and nearly 30-fold higher in the highest than in the lowest RWT tertile (14.7% vs 0.6%; OR, 29.5; 95% CI, 3.9–221.0).
“This finding emphasizes the importance of these factors of left ventricular geometry and this particular left ventricular concentric geometric pattern, which appears to have a significant influence on the surface ECG,” the authors write.
That said, DiFiori cautioned that the significance of the finding “remains to be determined. To say that the ECG is quote-unquote ‘abnormal’ is by definition correct, but it doesn’t mean that there is a clinical abnormality present.”
In the editorial, Sharma writes, “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.”
This is pertinent, he says, because exercise-associated sudden cardiac death (SCD) has been shown to be far more common in predominantly black National Collegiate Athletic Association (NCAA) Division I male basketball players (1 SCD/3126 student-athletes per year) than in NCAA athletes overall (1 SCD/43,770 student-athletes per yr).
He notes that the present study lacked information on blood pressure readings, use of performance-enhancing agents, and how comprehensively the athletes were investigated to exclude the broader phenotypic spectrum of hypertrophic cardiomyopathy.
TWI is very common in hypertrophic cardiomyopathy, but given that most cardiomyopathies are rare, with prevalence rates ranging from 1 in 500 for hypertrophic cardiomyopathy to 1 in 5000 for arrhythmogenic right ventricular cardiomyopathy, “it is unlikely that all of these black athletes with T-wave inversion have anything wrong with them,” Sharma told theheart.org | Medscape Cardiology.
“In my experience the positive predictive value for lateral T-wave inversion is 8%; this means that 92% will have nothing wrong,” he added. “More research is required in black athletes to investigate whether the actual pattern, duration, or amplitude of the T-wave inversions in these leads predict cardiac disease in black athletes.”
Finally, DiFiori agreed that further research is needed and said the present results were based on a unique population of elite athletes. As a result, they aren’t necessarily generalizable to other age groups or other athletes with different anthropomorphic characteristics. Still, the study should give some people pause about simply using an ECG as a screening tool as has been suggested to target at-risk athletes, particularly at the NCAA level.
The study was funded by the NBA as part of a medical services agreement between the NBA and Columbia University Medical Center. DiFiori, Sharma, and Waase reported no conflicts of interest.
Follow Patrice Wendling on Twitter: @pwendl. For more from theheart.org | Medscape Cardiology, follow us on Twitter and Facebook.
Tidak ada komentar:
Posting Komentar