Abstract 14176: Assessment of Atrial Septal Defect Dynamic Changes Within the Cardiac Cycle With Cardiovascular Computed Tomography

Abstract

Objectives: Successful and safe percutaneous closure of atrial septal defects (ASD) is contingent upon the accurate measurement of defect size and adjacent rim tissue, as well as the spatial relationship to other cardiac structures. Previous studies utilizing three-dimensional echocardiography have found significant changes in ASD defect size throughout the cardiac cycle. Cardiac computed tomography (CT) provides excellent spatial and temporal resolution of cardiac structures. Our study examines the efficacy of cardiac CT as a modality for evaluating dynamic changes in ASD defect size throughout the cardiac cycle. Methods: Thirty patients with an ostium secundum ASD underwent cardiovascular CT imaging prior to percutaneous or surgical repair. Cardiovascular CT was performed with a multidetector scanner and images were analyzed using a GE Advantage Workstation capable of advanced image processing and manipulation. ASD defect size was measured in the axial, coronal, and sagittal views at (end-systolic phase) 35% and (end-diastolic phase) 95% of the cardiac cycle. Results: In 30 participants the mean defect size was not significantly different across the three planes, axial mean was 22.4±15.3, coronal 23.7±16.2, and sagittal at 22.3±16.9, p=0.923. However, the change in defect size during the cardiac cycle was significantly different in all three views, P<0.0001 for all. On the axial view, the mean change from 35% to 95% was 6.5±4.9, while the coronal view change was 7.4±5.7, and the sagittal view change was 4.3±3.9. Additionally, the change in size increases with the defect size (figure 1). Conclusions: Cardiac CT imaging accurately depicts dynamic changes in ASD defect size throughout the cardiac cycle, and as such, may be considered a valuable and non-invasive imaging modality for patients undergoing pre-procedural evaluation.