Between December 1992 and December 1997, 55 consecutive children underwent repair of complete (31) or partial (24) atrioventricular septal defect. Mean age at operation was 5.3 months for complete (cAVSD), and 4.7 years for partial atrioventricular septal defect (pAVSD).
Associated lesions were coarctation (4/55), interrupted aortic arch (1/55), small left ventricle (5/55) and pulmonary stenosis (2/55).
One patient had a previous pulmonary artery banding.
In cAVSD, repair was performed with a double-patch technique and closure of the mitral cleft in all patients. In pAVSD, the primum septum defect was closed with a patch, and the mitral cleft was closed in all but 2 patients with a double orifice mitral valve.
Early deaths (3.6%) were confined to 2 infants with cAVSD, suffering from preoperative respiratory tract infections and intractable pulmonary hypertension. Late mortality was 5.4%.
Follow-up ranged from 8 to 68 months, and was 100% complete. Mitral valve insufficiency at latest follow-up or before reoperation was mild in 75% (40/53), moderate in 11% (6/53) and severe in 13% (7/53).
Reoperation was performed in 9 patients (17%), 7 with severe mitral regurgitation, and 2 with left ventricular outflow tract obstruction requiring a modified Konno operation. Mitral valve treatment consisted of further closure of the cleft in 7 patients, and l mitral valve replacement.
Risk factors for reoperation are small left ventricle, age less than 1 month at first operation, non-Down patients, and incomplete closure of the cleft. Stable primary repair of atrioventricular septal defect with complete closure of the mitral valve cleft can be performed with low mortality and acceptable intermediate results.