NONOBSTRUCTING ACCESSORY MITRAL-VALVE TISSUE AND VENTRICULAR SEPTAL-DEFECT

A 4-month-old boy with ventricular septal defect was found to have acc essory mitral valve tissue attached to the anterior leaflet of the mit ral valve. Operation was successfully performed to excise the accessor y mitral tissue in the left ventricular outflow tract and close the ve ntricular septal defect. Most previously reported cases with accessory mitral valve tissue were associated with left ventricular outflow tra ct obstruction. This boy had no pressure gradient across the left vent ricular outflow tract. The indications for prophylactic excision of no nobstructing accessory mitral valve tissue in a patient with other for ms of congenital cardiac disease are discussed.