Definition:

Pulmonary atresia with ventricular septal defect (PA-VSD) is a rare and complex cyanotic congenital heart malformation that has a high incidence of early mortality. PA-VSD presents with complete absence of any communication between the right ventricle and the pulmonary arteries. The blood supply to the pulmonary arteries is provided by a patent arterial duct or by major aorto pulmonary collateral arteries (MAPCAs). Two-thirds of the cases with pulmonary atresia are associated with MAPCAs, which can vary greatly in number and site of origin. PA-VSD shares similarities with tetralogy of Fallot (TOF) and has been considered a severe end of the spectrum of TOF. Although surgical interventions have been employed successfully for a number of years, the long-term prognosis has remained poor with an increased incidence of sudden death. An association between conotruncal cardiac abnormalities and 22q11.2 deletion during fetal life has been investigated and reported to occur in 20% of cases of PA-VSD.