Background: The most common congenital heart abnormality in neonates is the patent ductus arteriosus (PDA). The preferred course of treatment for PDA is transcatheter device closure (TCC) in people of all ages. Adequate imaging is important to delineate the PDA. Echocardiographic and angiographic measurements of PDA both can guide device selection for transcatheter patent ductus arteriosus closure (TCPC). Currently angiographic imaging of ductus is the gold standard. Echocardiographic imaging may be good enough to substitute angiography for device selection in the Zagazig University Hospitals. Objectives: The aim of the current work was to investigate the efficacy of transthoracic echocardiography (TTE) in determining type & dimensions of PDA and to anticipate device size to be used during TCC. Patients and methods: This prospective cohort study included a total of 24 patients with hemodynamically significant PDA aged 44.04 ± 44.9 months, both male and female and their weight more than 6 kg, treated at Pediatric Cardiology Unit, Department of Cardiology, Zagazig University Hospitals. Echocardiographic and angiographic examination were done. Results: There were no statistically significant differences between either the aortic ampulla diameter, narrowest PDA diameter and detection of type of PDA measured by echocardiogram and that measured by angiography.  Conclusion: It could be concluded that using TTE-guidance can make echocardiography even simpler with fewer complications. Routine echocardiography is a useful tool for planning interventions and, in some circumstances, for directing transcatheter closure.