CHICAGO – Results of the first-ever large study of ECG-based criteria for use in sports preparticipation screening in adolescent athletes demonstrate that the so-called Refined criteria decisively outperform the European Society of Cardiology and Seattle criteria, Dr. Aneil Malhotra reported at the annual meeting of the American College of Cardiology.
All three sets of 12-lead ECG criteria maintained an overall 92% sensitivity for the detection of serious cardiac pathology. However, the Refined criteria provided a major boost in specificity – and a markedly lower false positive rate, according to Dr. Malhotra of St. George’s, University of London.
The Refined criteria performed particularly well in the black adolescent athletes. That’s important because of black athletes’ historically high false positive rates with other ECG criteria, which lead to the time and expense of further testing, needless anxiety for the athletes and their families, and susceptibility to erroneous disqualification, he added.
The ESC recommendations for ECG interpretation in athletes were published in 2010 (Eur Heart J. 2010 Jan;31:243-59). Because of their high false positive rates and the fact that the ESC criteria were derived exclusively from white athletes, an international consensus panel subsequently issued the Seattle criteria, which were developed based upon data from both black and white athletes (Br J Sports Med. 2013 Feb;47:122-4).
While the Seattle criteria performed better than the ESC criteria, many sports cardiologists felt there was further room for improvement in setting criteria that differentiate between physiologic ECG patterns and those indicative of serious cardiac disease. Thus, another international expert consensus panel came up with the Refined criteria. And while the Refined criteria clearly outperformed the ESC and Seattle criteria when applied to a large group of young adult athletes (Circulation. 2014 Apr 22;129:1637-49), the fact is that all three sets of criteria were developed with data from adult athletes. None had been tested in adolescent athletes, even though they are vastly more numerous than were adult athletes in every country. It was the need to validate the applicability of the adult-based criteria in adolescent athletes that was the impetus for Dr. Malhotra’s retrospective study.
He and his coinvestigators applied all three sets of criteria to a unique data set: 10,156 elite adolescent soccer players in the English Football Association’s program for the development of soccer professionals. The cohort consisted of 9,262 white and 894 black players, making this the largest-ever study conducted in adolescent black athletes. The subjects averaged just over 16 years in age and trained on average for more than 12 hours per week.
The English Football Association’s preparticipation screening program included a full history and physical examination, a 12-lead ECG, and – most importantly – an echocardiogram for every athlete, which enabled investigators to validate the ECG findings. The cost of echocardiography in young English footballers is covered by Cardiac Risk in the Young, a charitable organization.
Application of the ESC criteria resulted in an abnormal ECG requiring further investigation in 12.9% of the white athletes. With the Seattle criteria, this rate dropped to 4.2%. With the Refined criteria, it fell further to 2.8%.
In black adolescent athletes, the abnormal ECG rate was 16.2% with the ESC criteria, 5.8% with the Seattle criteria, and 3.8% using the Refined criteria.
A total of 36 cases of cardiac conditions predisposing to sudden cardiac death were identified in the overall cohort. Thirty-three of the 36 affected athletes were correctly identified by all three sets of ECG criteria, including all 28 cases of Wolf-Parkinson-White syndrome and the three cases of hypertrophic cardiomyopathy.
Armed with the true positive rates, the investigators were able to determine that the false positive ECG rates were 12.6% in whites and 15.5% in blacks with the ESC criteria, 3.9% in whites and 5.3% in blacks with the Seattle criteria, and 2.5% in whites and 3.1% in blacks by the Refined criteria.
The positive predictive value of the 12-lead ECG was more than fourfold higher with the Refined as compared with the ESC criteria: 11% versus 2.5% with the ESC and 7.5% with the Seattle criteria, Dr. Malhotra continued.
He explained that the Refined criteria differ from the other two sets of criteria as follows: There are a series of normal ECG findings in the adolescent athletes that are unrelated to training, and that experts agree don’t warrant further evaluation, such as incomplete right bundle branch block or sinus bradycardia. And there are well established ECG abnormalities that necessitate further testing. The Refined criteria establish an evidence-based set of borderline ECG findings that are deemed normal in isolation: atrial enlargement, axis deviation, and complete bundle branch block. Only if two or more of these findings are present is the ECG deemed abnormal.