Natural course of atrial septal aneurysm in children and the potential for spontaneous closure of associated septal defect.

Atrial septum aneurysm (ASA), usually involving the region of the fossa ovalis, has rarely been described in children. In this study, the incidence and natural course of this anomaly were prospectively evaluated in 3,500 children referred for echocardiographic examination. ASA was found in 35 patients, 19 female and 16 male (1.0%). Patients were 6 years of age or younger at the time of diagnosis and 18 were neonates. None of the 750 children with normal echocardiograms had ASA. The most common associated lesion was atrial septal defect (ASD), which occurred in 24 of the 35 patients (69%). Other associated cardiac lesions were ventricular septal defect in 10, pulmonary stenosis in 5, patient ductus arteriosus in 4 and coarctation or interruption of the aorta with subaortic membrane in 2. No clinical complications were associated with ASA. Six patients with complex heart disease died. When associated with ASD, the direction of the ASA motion and that of the shunt found by Doppler echocardiography were similar. Fourteen patients with ASD were followed for 0.5 to 4 years. In 8 the ASD closed and in 6 the ASA disappeared. In 6 patients the ASD and ASA persisted until the end of the follow-up (p less than 0.01). Thus, the incidence of ASA in children in this series was higher than previously presumed and usually was associated with other cardiac anomalies, mainly ASD. In children, ASA tends to disappear with age and may have a role in spontaneous closure of associated ASD.