The role of echocardiography in the evaluation of cardiac re-modelling and differentiation between physiological and pathological hypertrophy in teenagers engaged in competitive amateur sports

SOX4 as a potential therapeutic target for pathological cardiac hypertrophy

Pathological cardiac hypertrophy can lead to heart failure, making its prevention crucial. SOX4, a SOX transcription factor, regulates tissue growth and development, although its role in pathological cardiac hypertrophy is unclear. We found that the SOX4 expression was elevated in hypertrophic hearts and angiotensin II (Ang II)-treated neonatal rat cardiomyocytes (NRCMs), and knocking down the SOX4 expression in NRCMs and mouse hearts significantly reduced the hypertrophic response. Mechanistically, SOX4 can bind to the SIRT3 promoter, inhibit SIRT3 transcription and expression, and thus affect downstream MnSOD acetylation levels, leading to abnormal increases in ROS and oxidative stress levels and promoting the occurrence of cardiac hypertrophy. In conclusion, this study identified a new role for SOX4 in regulating cardiac hypertrophy, and decreasing SOX4 expression may be a potential treatment for pathological cardiac hypertrophy.

Training intensity influences left ventricular dimensions in young competitive athletes

Background

In young athletes, exercise causes changes in the heart that include growth in wall thickness and mass of the left ventricle and expansion of the heart’s chambers. The heart’s function is either preserved or enhanced, but this may change to the opposite over time.

Objective

This study aimed to assess structural and functional cardiac adaptations in relation to exercise training time, intensity, and performance in young competitive athletes.

Methods

A total of 404 children and adolescents (14.23 ± 2.0 years, 97 females) were enrolled in the Munich Cardiovascular Adaptations in Young Athletes Study (MuCAYA-Study). Eighty-five participants were examined two times a year. Two-dimensional echocardiography was performed to assess left ventricular structure and function. Training time and intensity was measured with the MoMo physical activity questionnaire, maximum aerobic capacity by cardiopulmonary exercise testing, and strength with the handgrip strength test.

Results

Maximum aerobic capacity significantly influenced interventricular septal thickness in diastole. Training intensity significantly influenced left ventricular internal diameter in diastole and systole, and left ventricular mass indexed to body surface area. Within one year, interventricular wall thickness, relative wall thickness and left ventricular mass, indexed to body surface area and height, increased significantly. Training intensity and aerobic capacity contributed to cardiac adaptations in young competitive athletes, as represented by altered structural parameters but preserved cardiac function. Within a year, however, structural changes and a decline in diastolic performance were observed within the longitudinal sub-sample.

Conclusion

Our results confirm the hypothesis that cardiac adaptations to exercise occur at a young age. Cardiac adaptation in our cohort was influenced by exercise intensity and maximum aerobic capacity.