Balloon Occlusive Diameter of Non-Circular Atrial Septal Defects in Transcatheter Closure with Amplatzer Septal Occluder

BACKGROUND AND OBJECTIVES The aim of this study was to investigate the balloon occlusive diameter (BOD) of non-circular defects in the transcatheter closure of atrial septal defect (ASD). SUBJECTS AND METHODS A total of 67 patients who had undergone transcatheter closure of an ASD were reviewed retrospectively. A non-circular defect was defined as the ratio of the short diameter to the long diameter of the defect on the en-face image less than 0.75. The BOD was compared with the long diameter of the defect and then compared between the two groups. RESULTS There were 22 patients with circular defects and 45 patients with non-circular defects. The difference in BOD measuring from the long diameter of the defect was quite different between the two groups and significantly smaller in non-circular morphology (0.1±4.0 vs. 2.3±2.1, p=0.006). The difference in BOD measurement from the long diameter of ASD showed a positive correlation with the ratio of the short diameter to the long diameter of ASD (b/a) (r(2)=0.102, p=0.008). In the non-circular morphology of ASD, the difference in BOD measured from the long diameter had a significant negative correlation with the long diameter of ASD (r(2)=0.230, p=0.001), whereas in circular ASD, no significant correlation was found between the difference in BOD and the long diameter of ASD (p=0.201). CONCLUSION The BOD compared with the long diameter measured from three-dimensional transesophageal echocardiography was smaller in non-circular ASD than in circular ASD. This difference was much smaller in non-circular ASD with a large long diameter.