Late development of functional subvalvar stenosis after repair of truncus arteriosus.

The late development of subvalvar stenosis following truncus repair is described. It may occur in patients with an overriding truncal valve and a relatively small ventricular septal defect (VSD) closed with an inappropriately sized patch. Management consisted in enlarging the VSD and closing it with a large, tailored patch. Consideration should be given to enlarging the VSD at the time of original repair if the truncal valve is overriding.