INTRODUCTION:

Pulmonary atresia with ventricular septal defect (VSD) belongs to a group of complex congenital cardiac malformations, characterized by lack of luminal continuity and blood flow from ventricle/pulmonary artery with variable sources of pulmonary blood supply and arborization abnormalities. The pulmonary blood supply in these anomalies can be derived from a variety of sources, including native pulmonary artery, patent ductus arteriosus and major aorto-pulmonary collaterals(MAPCA) with significant variability in pulmonary blood supply from patient to patient. As MAPCAs supply  pulmonary circulation in congenital cardiac disease when  the  native  pulmonary  circulation is underdeveloped, these are seen in the other congenital anomalies as well, eg:  Tetrology of Fallot, Tranposition of great arteries,double outlet right ventricle (1,2,3,4)