Abstract Seventy-six patients (36 boys and 40 girls) with patent ductus arteriosus who had successful ductal occlusion with a Rashkind umbrella device were monitored for a period of 6 to 60 months (mean 26.7 ± 12.3 months). All patients were evaluated by pulsed and color Doppler echocardiography before and after the procedure. The prevalence of residual leff-to-right shunt and main pulmonary artery flow pattern were assessed. Residual left-to-right shunt was seen in 12 (15.7%) patients 24 hours after the procedure, but the shunt was small with a pulmonary-to-systemic blood flow ratio of < 1.3:1. Repeat echo Doppler study at 14 days showed residual left-to-right shunt in 10 (13.1%) patients. None of these patientsshowed further decrease in prevalence of residual left-to-right shunt. The patients with residual left-to-right shunt had larger ductii (mean 5.17 ± 0.88 mm, range 4.23 to 6.6 mm) as compared to patients with no residual left-to-right shunt (3.31 ± 0.86 mm, range 1.8 to 4.69 mm; p < 0.001). Two patients with residual shunt had successful ductus reocclusion, with 12 and 17 mm devices, respectively, at 28 month of follow-up. The Rashkind umbrella device is effective in closing ducti with diameters of < 5 mm in majority of patients.