Abnormal electrocardiographic findings in athletes: Correlation with intensity of sport and level of competition

Introduction: Athletes can exhibit abnormal electrocardiogram (ECG) phenotypes that require further evaluation prior to competition. These are apparently more prevalent in high-intensity endurance sports. The purpose of this study was to assess the association between ECG findings in athletes and intensity of sport and level of competition. Methods: A cohort of 3423 competitive athletes had their ECGs assessed according to the Seattle criteria (SC). The presence of abnormal ECGs was correlated with: (1) intensity of sport (low/moderate vs. at least one high static or dynamic component); (2) competitive level (regional vs. national/international); (3) training volume (≤20 vs. >20 hours/week); (4) type of sport (high dynamic vs. high static component). The same endpoints were studied according to the ‘Refined Criteria’ (RC). Results: Abnormal ECGs according to the SC were present in 225 (6.6%) athletes, more frequently in those involved in high-intensity sports (8.0% vs. 5.4%; p=0.002), particularly in dynamic sports, and competing at national/international level (7.1% vs. 4.9%; p=0.028). Training volume was not significantly associated with abnormal ECGs. By multivariate analysis, high-intensity sport (OR 1.55, 1.18-2.03; p=0.002) and national/international level (OR 1.50, 95% CI 1.04-2.14; p=0.027) were independent predictors of abnormal ECGs, and these variables, when combined, doubled the prevalence of this finding. According to the RC, abnormal ECGs decreased to 103 (3.0%), but were also more frequent in high-intensity sports (4.2% vs. 2.0%; p20 horas/semana); 4) tipo de desporto (elevados componentes dinâmico versus estático). Os mesmos endpoints foram estudados pelos Refined Criteria (RC). Resultados: De acordo com os SC, 225 (6,6%) atletas tinham alterações patológicas, mais frequentes nos envolvidos em desportos de elevada intensidade (8,0 versus 5,4%; p=0,002), sobretudo dinâmica, e em nível nacional/internacional (7,1 versus 4,9%; p=0,028). O volume de treino não esteve significativamente associado a estas alterações. Em análise multivariada, desporto de elevada intensidade (OR 1,55, IC 95% 1,18-2,03; p=0,002) e o nível nacional/internacional (OR 1,50, IC 95% 1,04-2,14; p=0,027) foram preditores independentes de ECG anormais, variáveis que combinadas duplicaram a prevalência. Com os RC o número de ECG patológicos decresceu para 103 (3,0%), também mais frequentes nos desportos de elevada intensidade (4,2 versus 2,0%; p