Natural history of medium-sized atrial septal defect in pediatric cases

BackgroundThe indication for surgical repair of atrial septal defect (ASD) is pulmonary to systemic blood flow ratio (Qp/Qs) > 2.0, and therapeutic strategy depends on the facility in cases of Qp/Qs 1.5–2.0. Defect size increases with age, but hemodynamic changes of medium-sized ASD (Qp/Qs 1.5–2.0) are unknown.Methods and resultsFrom April 1, 1985 to March 31, 2008, we experienced 125 cases of cardiac catheterization for ASD. Twelve cases were re-evaluated without surgical repair. The first and second catheterizations were performed at median ages of 7 years (range, 2–13 years) and 16 years (range, 5–19 years), respectively. The mean follow-up period was 7 years. Qp/Qs increased from 1.6 to 2.0 during follow-up (p < 0.05). Of four cases with Qp/Qs < 1.5 at initial presentation, three had Qp/Qs ≥ 1.5 at second inspection. Right ventricle diastolic volume (RVEDV/LVEDV) also increased.ConclusionsQp/Qs and RVEDV/LVEDV of medium-sized ASD increase together in childhood. Re-evaluation before adulthood should be considered in patients with no indications of ASD closure in childhood.