Systemic to pulmonary artery shunt is one of the important treatments in pulmonary atresia–ventricular septal defect (PA-VSD). There are controversial views about the effects of shunt on the growth of pulmonary artery tree. The aim of this study was to assess the early and late effects of systemic to pulmonary shunt by angiography on the increase of pulmonary artery indices (Nakata and Mc Goon), and development of complications in patients with PA-VSD. We retrospectively reviewed the results of 19 PA-VSD patients having systemic to pulmonary shunt and had pre and post operation angiography (inclusion criteria). None of them had large collateral or PDA (exclusion criteria). The mean age of the patients was 5 ± 3.6 years. Ten patients had left shunts, 8 cases had right shunts and one case had a central shunt. After shunt the mean increase in Nakata index was 40.8 mm2/m2 (P=0.08) and in McGoon index was 0.11 (P=0.23). A major stenosis was observed in 1 case. The increase of McGoon index was higher in right shunts and in early years after the operation. We can conclude that systemic to pulmonary shunt can be performed with low risk, providing good palliation and is associated with relative increase of pulmonary artery indices (not significant), and low incidence of major stenosis, especially when the shunt was performed in more than two years old patients
