This prospective study was carried in Pediatric department, Cairo University on 30 infants (15 males and 15 females)with congenital heart diseases associated with left-to-right shunt and increased pulmonary flow and pulmonary hypertension. Pre- and post-operative echocardiography and infant pulmonary function testing (PFT) was done with follow-up up to 6 months. A statistically significant improvement in echocardiographic functions and PFT was noted as well as a statistically significant correlation between pulmonary artery pressure and PFT.