Spontaneous closure of secundum atrial septal defect in infants and young children.

The records of 264 pediatric patients with uncomplicated ostium secundum atrial septal defect (ASD) were reviewed. Eighty-seven patients were younger than age 4 years at the time of cardiac catheterization. Subnormal weight gain, frequent pneumonia, cyanosis or tachypnea were present in 26 patients (30%). Of the 36 infants at catheterization, 17 (48%) had the previously described symptoms, including 12 (33%) who had congestive heart failure. Eight of the 36 infants were found to have closed their defect at a subsequent catheterization. Six of 18 patients who underwent cardiac catheterization between 1 and 2 years of age also had spontaneously closed their ASD at subsequent study. Statistical analysis of hemodynamic data revealed no difference (except a smaller shunt size) between ASDs that closed and those that did not in patients who were less than 4 years at initial catheterization. Analysis of hemodynamic data revealed no statistical differences between groups of patients with an ASD who were younger than and those older than 4 years at time of diagnostic study. Patients with ASDs that closed were significantly different from patients with atrial level shunting thought to be secondary to a valve-incompetent foramen ovale with respect to age at initial study (11 versus 2 months, p less than 0.001), mean left atrial pressure (7.7 versus 12.3 mm Hg, p less than 0.02) and difference between mean right and left atrial pressures (1.0 versus 4.2 mm Hg, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)