[Echocardiographic assessment of atrial septal defect size (author's transl)]

In 31 patients, aged 3 to 15 years, with atrial septal defects (secundum type) and varying degrees of left-right shunt volumes, 2-dimensional echocardiography was employed to assess the percent length of the defect with respect to total interatrial septal length. Visualization of the septum was achieved through the "4-chamber view" from the apical position (Figure 2). The calculated echocardiographic defect size was expressed in percent of the total interatrial septal length for comparison with the per cent shunt calculated from standard cardiac catheterization. There was good agreement in the patient group with defects found to be associated with less than 40% left-right shunt; in those with larger shunt volumes, the echocardiographically-determined values overestimated the oxymetrically-determined values (Figure 3). Thus, the results show that this non-invasive method is capable of providing useful information with respect to atrial septal defect size and subsequent indication for surgical closure.