Assessment of atrial septal defect size and residual rim using real-time 3D transesophageal echocardiography

Accurate preoperative determination of defect location and size is important for successful transcatheter closure of atrial septal defects (ASD). Real-time 3D transesophageal echocardiography (3DTEE) has the potential to delineate the shape of ASD in 3D space.

Full volume and 3D zoom datasets by 3DTEE were acquired in 17 ASD patients. Using quantitative software, maximal/minimal diameter, defect area and residual rim length were measured and compared to the standard 2D measurements.

Real-time 3DTEE allowed delineation of the en-face view of the ASDs. The defect typically had an oval shape, and its size changed dynamically, having its minimal size at end-diastole and maximal at end-systole. A good correlation was noted between the maximal defect area by 3DTEE and 2DTEE (r = 0.93, p < 0.001). Successful delineation of rim length to the specific cardiac structure was 100% by 3DTEE and 88% by 2DTEE. There was a fair correlation of residual rim length between 3DTEE and 2DTEE (r = 0.69, p < 0.001). Eight patients underwent transcatheter closure of the ASD. Excellent correlation was noted between 3D-derived maximal defect diameter and device diameter (r = 0.97, p < 0.001).

Real-time 3DTEE allows measurements of the temporal and spatial changes of ASD size and shape. This methodology provides detailed information on defect dynamics.