Supracristal ventricular septal defects: spectrum of associated lesions and complications.

The clinical records and radiographs of 46 patients with a supracristal ventricular septal defect are reviewed to illustrate the spectrum of associated lesions and complications seen with this defect. The presence of a supracristal ventricular septal defect compromises the normal conal muscular support of the aortic valve, usually in the region of the right sinus of Valsalva, and, consequently, complications involving the aortic valve are frequently noted. Decreased sinus support may lead progressively to prolapse of the right aortic cusp through the supracristal ventricular septal defect into the right ventricular infundibulum effecting sequentially aortic regurgitation, right ventricular outflow obstruction, and ultimately right sinus of Valsalva-right ventricular fistula. This potential progression is an indication for early recognition and repair of the supracristal ventricular septal defect. A supracristal ventricular septal defect is also an integral component of the Taussig-Bing malformation, is present in the majority of patients with aortic arch interruption, and may be seen in as many as 25% of Oriental patients with tetralogy of Fallot.