Fascination with pulmonary atresia and intact ventricular septum (PAIVS) reflects its diversity and evolving management strategies. We will discuss PAIVS with situs solitus and concordant atrioventricular and ventriculoarterial connections.

Usually the cavity of the right ventricle (RV) is small (hypoplastic), the RV myocardium is thickened, and the RV pressure is at supra systemic levels. In a minority with severe tricuspid regurgitation the RV is dilated and thin walled and postnatally the RV pressure is low. Also contributing to the morphological heterogeneity are the size and structure of the tricuspid valve (TV), whether RV outflow tract obstruction (RVOTO) is muscular or valvar, and the presence or absence of coronary artery abnormalities. Postnatal survival initially is dependent on persistence of the arterial duct. Management strategies are influenced by the nature of the RVOTO and whether the RV is considered suitable for eventual inclusion in the circulation. Should there be a biventricular, univentricular or one-and-a-half ventricle repair?

INCIDENCE

In a 20 year population based study in Sweden (1980–1999)1 84 children were born with PAIVS, giving an incidence of 4.2 per 100 000 live births. In the UK/Eire from January 1991 to December 1995 all fetuses and infants born with PAIVS were documented in a multicentre, population based collaborative study.2 There were 183 live births with an overall incidence of 4.5 per 100 000 live births. Significant (p = 0.01) regional differences were found with an incidence of 4.1 per 100 000 in England and Wales, 4.7 in Scotland, 6.8 in Eire, and 9.6 per 100 000 in Northern Ireland. There were 86 fetal diagnoses made at a mean of 22 weeks gestation leading to elective termination of pregnancy (TOP) in 61%, four intrauterine deaths (5%), and 29 (34%) live births. If there were no TOP or spontaneous deaths, the incidence at birth would be 5.6 per 100 000 in …