[Two-dimensional echocardiography in the study of aneurysms of the membranous interventricular septum].

Seven patients with angiographically proven aneurysm of the membranous interventricular septum associated with membranous ventricular septal defect were studied by two-dimensional echocardiography. In all patients a curvilinear, dome-shaped echo arising from the upper ventricular septum and bulging toward the right ventricular cavity in systole was identified. This finding was detected in all long axis views (7/7), and 4/7 short axis views, in 4/6 apex four chamber views and in 3/6 subcostal four chamber views. Two-dimensional echocardiographic studies in forty patients with angiographically proven membranous ventricular septal defect, but not septal aneurysm, revealed only one case with similar findings, suggesting ventricular septal aneurysm, in the long axis and apex four chamber views. We conclude that two-dimensional echocardiographic imaging of a curvilinear echo in the proximal interventricular septum, bulging toward the right ventricle in systole and visualized in different planes, is very suggestive of aneurysm of the membranous ventricular septum. Two-dimensional echocardiography appears to have acceptable specificity for the diagnosis of aneurysms of the ventricular septum.