Adult presentation with a bilobed membranous ventricular septal aneurysm.

Membranous ventricular septum aneurysm (MVSA) is an uncommon cardiac abnormality primarily associated with the spontaneous closure of a small membranous ventricular septal defect in childhood. Diagnosis of an idiopathic MVSA in an adult is exceedingly rare. We report on a man, aged 38 years, with a bilobed MVSA diagnosed by transesophageal echocardiography and gated computed tomography, with separate aneurysm sacs extending into the right atrium and right ventricle.