Cross-sectional echocardiographic measurement of right atrial and right ventricular size in children with atrial septal defect before and after surgery.

A total of 25 children operated on for atrial septal defect were studied by cross-sectional echocardiography before and after operation. Right atrial and right ventricular dimensions and areas were measured preoperatively and 1-4 years (median, 32 months) postoperatively. The length, width, and area of the right atrium (RA) and the right ventricle (RV) were measured in the apical and the subcostal four-chamber views. The dimension of the RV outflow tract (RVOT) was measured in the parasternal short-axis view. Preoperatively, all group mean values except the subcostal four-chamber length of the RV were significantly larger than normal. After surgery, there was a significant decrease in all of the parameters studied, except for RV length. The mean postoperative values of RA measurements in the apical four-chamber view and of RVOT were still significantly larger than normal. The RV four-chamber measurements except the apical four-chamber length were not significantly enlarged. The greatest decrease in RA and RV size occurred in the first postoperative year. Longer follow-up periods did not change the measurements significantly.