Evaluation of causal heart diseases in cardioembolic stroke by cardiac computed tomography

Figure 19  Atrial septal aneurysm with atrial septal defect. A 66-year-old man underwent cardiac computed tomography (CCT) to further evaluate outpouching of the interatrial septum observed on transthoracic echocardiography. Transthoracic echocardiography did not detect interatrial shunt flow. A: Horizontal long axis reformatted CCT image shows right bulging atrial septal aneurysm [Atrial septal aneurysm (ASA), asterisk]. B: Above ASA, in upper portion of interatrial septum just below aortic valve, atrial septal defect (ASD) with contrast shunt from LA into RA is found (arrow). Measured size of ASD is 14 mm by 10 mm; C: Below ASA, in lower portion of interatrial septum, another 5 mm-sized ASD with left to right shunt is found (arrowhead). LA: Left atrium; RA: Right atrium.