Clinical practice is discrepant regarding routine enlargement of the interatrial communication (IAC) in patients with right-sided atrioventricular valve atresia. We determined the percentage and risk factors of those who develop a restrictive IAC.

Medical records were reviewed for patients treated from 1985 to 2006, including those admitted in the first 6 weeks of life (group A), and those referred at a later age (group B), some of whom had routine atrial septal procedures. In group A, we analyzed the initial postnatal echocardiogram.

Group A consisted of 79 patients, 16 of whom had an atrial septectomy as part of the initial surgical procedure. Of the remaining 63 patients, 9 (14%) developed atrial septal restriction. In group A, an atrial septal aneurysm (ASA) (OR 16, P = .006) and IAC diameter <5 mm (OR 13, P = .009) were associated with atrial septal restriction. Atrial septal restriction occurred in 80% of patients with both features, 20% with IAC ≥5 mm and ASA, 18% with IAC <5 mm and no ASA, and 2% with neither feature. Group B consisted of 95 patients, 27 of whom had an atrial septal procedure. Of the remaining 68 patients, 11 (16%) developed atrial septal restriction.

Routine enlargement of the IAC is not necessary in patients with right-sided atrioventricular valve atresia. Patients with ASA or IAC <5 mm are at increased risk for development of atrial septal restriction.