This randomized controlled trial evaluates the efficacy, safety, metabolic, and cardiovascular effects of liraglutide in children aged 6 to 12 years with severe obesity. Participants are randomized to receive liraglutide plus lifestyle intervention or lifestyle intervention alone for 6 months. In addition to primary outcomes related to weight loss and metabolic improvement, a predefined subgroup analysis evaluates cardiovascular function in participants receiving liraglutide using advanced echocardiographic techniques, including speckle-tracking-derived myocardial deformation parameters.