[A case of large congenital right ventricular outflow aneurysm].

A rare case of large congenital right ventricular outflow aneurysm is reported. A 5-year-old girl had been diagnosed as having atrial septal defect and pulmonary valvular stenosis. A large cavity in front of right ventricular outflow was noticed by her follow-up echocardiography. The non-contracting cavity was confirmed as an aneurysm originating from right ventricular outflow tract by angiocardiogram. Surgical resection was performed successfully with concomitant atrial septal defect closure and pulmonary valvular commissurotomy. Histological examination revealed that the wall of the ventricular outflow aneurysm consisted of dense fibrous tissue, contained no myocardium, and the cavity was lined with endocardium. It is reported that rupture of congenital ventricular aneurysm may occur even if there is no symptom. Surgical resection will be recommended especially when increasing in size is diagnosed.