Transaortic closure of residual intramural ventricular septal defect

Background. Residual intramural ventricular septal defect is an unusual cause of left-to-right shunt after biventricular repair of conotruncal anomalies. It results from the insertion of the patch within the trabeculated right ventricular free wall related to the ventriculoinfundibular fold creating a communication through the intertrabeculated spaces to the right ventricular cavity. This complication often leads to unsuccessful reoperations unless the exact mechanism of the shunt has been identified. Methods and Results. Five patients presented with residual intramural ventricular septal defects. Three had double outlet right ventricle, one pulmonary atresia with ventricular septal defect, and one tetralogy of Fallot. One patient was unsuccessfully reoperated on for closure of the residual ventricular septal defect through the fight ventricular approach. The surgical treatment, which consisted of patch closure of the residual intramural ventricular septal defect through aortotomy, was successful in 3 patients. In the 2 remaining patients the hemodynamically insignificant residual intramural ventricular septal defect remained untouched. No mortality or morbidity occurred. Conclusions. Residual intramural ventricular septal defect should be suspected in presence of a residual ventricular septal defect after biventricular repair of conotruncal anomalies. It is not accessible through either atriotomy or right ventriculotomy. The transaortic approach allows an easy treatment of this rare complication. (C) 2000 The Society of Thoracic Surgeons.