SIGNIFICANCE OF AN ATRIAL SEPTAL ANEURYSM IN THE PRESENCE OF AN OSTIUM-SECUNDUM ATRIAL SEPTAL-DEFECT

The aim of this study was to elucidate the mechanism by which an atria l septal aneurysm is formed in the presence of an atrial septal defect by characterizing the distinguishing echocardiographic features of at rial septal defects between patients with and without an atrial septal aneurysm. The transesophageal echocardiograms of 30 consecutive patie nts who underwent surgical closure of a secundum atrial septal defect were compared with those of 8 normal controls. In patients with secund um atrial septal defect, the maximal diameter (mean +/- SD) of the fos sa ovalis was 21.73 +/- 3.43 compared to 11.43 +/- 1.00 mm in the cont rol group (p < 0.01). In the 7 (23%) patients with atrial septal aneur ysm, the mean maximal diameter of the fossa ovalis was 25.28 +/- 3.03 compared to 20.65 +/- 2.78 mm in those without an atrial septal aneury sm (p < 0.01). The atrial septal defect was smaller in patients with t han in those without an atrial septal aneurysm. In 4 patients with atr ial septal aneurysm who had a history of a cerebrovascular event, the interatrial communication was only detected by contrast echocardiograp hy. In conclusion, in patients with atrial septal aneurysm, atrial sep tal defects tend to be smaller but the incidence of cerebrovascular ev ents is greater.