Aneurysmal formation in the setting of muscular ventricular septal defects

To emphasize the formation of fibrous aneurysmal structures in the setting of muscular ventricular septal defects

Among patients with muscular ventricular septal defects followed in our institute, we described six who were diagnosed with formation of fibrous aneurysms. Of the patients, one was female and others were male. The age at diagnosis ranged from eight days to 16 years. In one, the defect opened between the ventricular inlets, but in the others the defects occupied the middle part of the apical trabecular septum.

The sizes of defects at initial echocardiographic evaluation ranged from 2.9 to 8 millimetres. The period of follow up for four patients was from 5 months to 7 years, one patient could not be followed up, and the other had already been diagnosed when first seen in our Institution. In our second and third patients, no aneurysm was seen during the initial echocardiographic evaluation, and it was recognized during follow-up. In these two patients, sequential echocardiographic examinations showed that the formation of the aneurysm made the defect smaller, with it almost closing in one.

Although seen most frequently in the setting of perimembranous defects, fibrous aneurysms can also form adjacent to, and reduce the size of, muscular ventricular septal defects.