Subpulmonary and subaortic ridges in doubly committed subarterial ventricular septal defect: an echocardiographic...

Certain conditions, including discrete subaortic stenosis and right ventricular outflow tract obstruction are well-known associations with ventricular septal defect. However, the association of discrete type subpulmonary and subaortic stenosis with ventricular septal defect has not been described to date.

In this report we present our experience in nine patients with doubly committed subarterial ventricular septal defect in whom associated discrete subpulmonary and subaortic stenosis were diagnosed by two-dimensional echocardiography. The mean age of the patients was 5.7 years, and eight of them were male. Two patients had additional hypertrophied anomalous muscle bundles with pressure gradients across the right ventricular outflow tract. Aortic valve prolapse was detected in two patients with one of them having mild aortic regurgitation.

Cardiac catheterization was performed in four patients, and three underwent surgery. Doubly committed subarterial ventricular septal defect was closed, and subpulmonary and subaortic ridges were resected in each patient. Histological findings were similar for both ridges, which were composed of thin, short and irregularly arranged elastic fibres covered by endothelial cells.

The finding of fibrous ridge on both sides of the doubly committed ventricular septal defect, where the turbulence is likely to be maximum, and the histopathological similarities of subpulmonary and subaortic ridges, may suggest a common mechanism for the development of fibrous ridges.

Serial echocardiographic assessment of patients with doubly committed ventricular septal defect is recommended.