Echocardiographic features of a giant aneurysm of membranous ventricular septum.

We describe the echocardiographic features of a 22-year-old female with a giant aneurysm of membranous ventricular septum (AMVS). Both transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) demonstrated significant dilatation of the aortic annulus and severe aortic regurgitation. A giant aneurysm was detected extending from a large membranous ventricular septal defect (MVSD) to the anterior surface of the aortic root. Contrast-enhanced CT and three-dimensional CT revealed a giant aneurysm located below the aortic root and connected to the left ventricular outflow tract (LVOT). The diagnosis was confirmed by surgery and postoperative pathological examination.