Background: Atrial septal defect (ASD) closure has become an established therapy. Novel echocardiographic methods have been developed to quantify global as well as regional ventricular function and are used for diagnostic and prognostic evaluation of various cardiovascular diseases. Objective: To assess the impact of transcatheter closure of secundum atrial septal defects on the left and right ventricular function using conventional and newer echo-Doppler modalities. Patients and methods: This study included 40 subjects with secundum ASD. Cases were assessed by transesophageal echo pre ASD closure to detect suitability for transcatheter ASD closure, then selected patients were evaluated by transthoracic echo-Doppler using conventional and recent modalities before closure, one month and three months after closure. Results: Post ASD closure there were increase in the Left ventricle (LV) dimensions and volumes, increase in LVEF, and reduction of LV-GLS compared to pre closure. The RV volumes, RV-GLS and RVEF were decreased post closure. Both LV Tei index and RV Tei index showed significant reduction post ASD closure. Conclusion: Transcatheter closure of secundum atrial septal defect leads to structural and functional changes in both ventricles in the form of: (a) reduction in RV dimensions and volumes with apparent deterioration of the RV systolic function, (b) increase in dimensions and volumes of the LV with apparent improvement of LV systolic function, and (c) apparent improvement of both left and right ventricular diastolic function post ASD closure.