Evaluation of electrical and structural changes in adolescent athlete's heart

Evaluation of Electrical and Structural Changes in Adolescent Athlete's Heart Introduction: Training causes electrical and structural adaptations in the heart. At times these adaptations may be confused with findings of diseases that cause sudden cardiac death. Therefore, it is of great importance to distinguish between training related changes and pathological changes. Although there are studies focusing on the cardiac findings of adult athletes, the interaction of the growing and maturing heart of child athlete with sports is not a subject that has been studied sufficiently. Aim: We planned to record the electrical and structural differences in the hearts of adolescent athletes' from different sports branches and to investigate the effects of age and training period on these changes. Materials and Method: A total of 93 athletes between the ages of 10-18, from the branches of water polo, swimming, football and triathlon who have been training more than 5 hours a week for at least 2 years, were included in our study. A control group of 41 healthy children between the ages of 10-18 who were matched to athletes in terms of mean age and anthropometric measurements and engaged in physical activity for less than 2 hours per week was formed for comparisons. Cardiovascular anamnesis and physical examination of all participants were completed according to a standard form. Following the physical examination, the patient's electrocardiography was taken. In addition, echocardiographic evaluation of 27 athletes was done. Results: In the athlete group the heart rate was slower by 14 beats / minute (p<0.000) and QTc distance was longer (407.4 ± 19.0 msec vs 398.8 ± 22.2 msec, p<0.03) compared to control group. The incidence of sinus bradycardia, partial right bundle branch block, early repolarization was higher in athletes (16% vs. 0, p<0.000; 50.5% vs. 22%, p:<0.02; 60.2% vs. 22%, respectively, p<0.00). More athletes meet with Sokolow-Lyon left ventricular hypertrophy criteria, Pegueri-Lo Presti left ventricular hypertrophy criteria, and Sokolow-Lyon right ventricular hypertrophy criteria than controls (42% vs 19,5% p <0,012; 61% vs 27% p<0.001 and 26% vs %5, p<0,000 respectively). Heart rate was lower, PR interval was longer, sinus bradycardia and early repolarization were more common in athletes older than 14 years old. While the frequency of negative T waves was found to be similar between athletes and controls, negative T waves and negative T waves in V1-V2 were more common in those under 14 within the athlete group. Premature ventricular contractions were detected in two participants in the athlete group. Apart from this, no pathological ECG findings were observed in any participant. In the echocardiographic evaluation of water polo players; IVSd Z-score was 3 ± 1.5 and IVSs Z-score was 2.9 ± 0.8. Other echocardiographic measurements were within normal reference ranges. IVSd, IVSs, IVSd Z-score, IVSs Z-score and IVS / LVPW were found to be increased in water polo players aged 14 and older (p <0.05). IVSs, IVSs Z-score and IVS / LVPW were higher in athletes training for five years or more (p <0.05). Conclusion: Our study confirms that regular and long-term training is associated with bradycardia, sinus arrhythmia, partial right bundle branch block, repolarization changes and ventricular hypertrophy in children and adolescent athletes. It is observed that the frequency and distribution of some of these changes are affected by chronological age and duration of training. In our study, we also showed that the thickness of the interventricular septum in echocardiography was greater than the upper limit of the accepted reference range and that its thickness increased compared to the posterior wall of the left ventricle in water polo players who trained regularly and for a long time. Keywords: Adolescent athlete's heart, electrocardiography, echocardiography