The aim of this study was to evaluate the impact of balloon pulmonary valvuloplasty on longitudinal ventricular dysfunction and cardiac dyssynchrony in children with congenital moderately severe pulmonary stenosis (PS). Forty-eight children with congenital moderately severe valvular pulmonary stenosis and 36 age-matched normal children were included. Successful percutaneous balloon pulmonary valvuloplasty was performed for children with PS. Longitudinal Cardiac function and myocardial synchrony was assessed by echocardiography with tissue Doppler imaging (TDI). Mitral annular plane excursion (MAPSE), tricuspid annular plane excursion (TAPSE), left ventricular systolic wave (LVs), right ventricular systolic wave (RVs) and myocardial synchrony was assessed by echocardiography with TDI. TAPSE, RVs, TAPSE/MAPSE ratio and RVs/LVs ratio were significantly lower in children with PS compared to control subjects: (P < 0.001, P < 0.001, P < 0.001 and P < 0.001). All these parameters were significantly improved after balloon valvuloplasty in children with PS. Intra& inter-ventricular dyssynchrony were significantly increased in PS patients than in control group, (P < 0.03, <0.001 and 0.02 respectively). All these variables were significantly reduced after pulmonary valvuloplasty. In children with valvular PS, balloon valvuloplasty restored longitudinal function and cardiac Synchrony. This gives good insights for the importance of early intervention in children with PS to prevent the progression for cardiac deformation.