THE INFLUENCE OF EARLY LEFT VENTRICLE REMODELING OVER QTC CHANGES IN HIGHLY TRAINED PREADOLESCENT FOOTBALLERS

Aim. To assess the correlation between left ventricle remodeling induced by physical training with QTc duration in preadolescent professional football players.

Material and methods. Ninety-four highly trained male footballers (mean aged 12,85±0,84) competing in the Serbian Football League (at least 7 training hours/ week) and 47 age-matched healthy male controls were enrolled in the study. Main outcome measures: They were screened by ECG and echocardiography at a tertiary referral cardio center. The control group had sedentary life style (less than 2 training hours/week). QTc values and left ventricle dimensions were compared in these two groups.

Results. In all participants, normal values of QTc interval were registered. Mean QTc in athletes was significantly higher compared to non-athletes (419,89±13,07 msec vs 399,78±13,27 msec) (p<0,001). QTc interval had strong positive correlation to left atrium dilatation, LV dilatation, LV mass and LV mass index. There was no correlation between QTc interval and LV wall thickness, but there were correlations between QTc interval duration and specific LV mass indexes (LVM/BSA 1,5 and LVM/h 2.7).

Conclusion. QTc interval prolongation is present in early stage of athlete’s heart remodeling, hence QTc prolongation could be the early ECG marker of physiological LV remodeling in young preadolescent footballers, without any other standard ECG and echocardiographic signs of early LV hypertrophy. This could be explained by a different pattern of left ventricle remodeling in preadolescent period, where LV wall thickness increase cannot usually be seen and the predominant characteristic is left ventricle dilatation.

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