Cardiac Rehabilitation of Children and Adolescent With Long QT Syndrome

Children and adolescents with inherited cardiac arrhythmia su ch Long QT Syndrome (LQTS) have lower physical and quality of life than their healthy peers. A multi-component cardiac rehabilitation, including an exercise training program and education program, might counteract those effects. The goal of this pilot study is to evaluate the security, feasibility, and benefits of a cardiac rehabilitation program in children with LQTS aged between 6 to 18 years old. The main question\[s\] it aims to answer are: * Is center-based cardiac rehabilitation safe and feasible for children with LQTS? * Does a 12-week cardiac rehabilitation program improve physical fitness and quality of life?