Background:
The combination of an atrioventricular septal defect with a common atrioventricular junction guarded by a common valve, and double-outlet right ventricle, is a rare lesion that presents a challenge for surgical repair. This report describes our surgical approach and results in 16 patients undergoing biventricular repair for such a combination of lesions.

Methods:
A retrospective analysis was performed for all patients undergoing biventricular repair of atrioventricular septal defect with common atrioventricular valve and double-outlet right ventricle between 1991 and 2008. Patients with tetralogy of Fallot and common atrioventricular valve were excluded from analysis. Early and actuarial outcomes were evaluated using the χ² test for categorical variables and Wilcoxon rank sum for ordinal variables.

Results:
The median age at operation was 16 months. Heterotaxy syndrome was present in 12 of the 16 patients (9 right isomerism and 3 left isomerism), and 6 had concurrent totally anomalous pulmonary venous connections. Primary repair was achieved in 6 patients, and 10 underwent one or more prior operations (most frequently a shunt, banding of the pulmonary trunk, or repair of the anomalous pulmonary venous connections). Enlargement of the ventricular septal defect by resection of the muscular outlet septum was required in 11 patients, in whom the ventricular septal defect emptied entirely or primarily to the inlet of the right ventricle. A conduit was placed from the right ventricle to the pulmonary arteries in 13. There was 1 death before discharge from hospital, 1 late death, and 2 episodes of heart block. Among survivors, follow-up was complete with a median follow-up of 66 months. No patient had late obstruction of the left ventricular outflow tract. The presence of heterotaxy with totally anomalous pulmonary venous connections was associated with combined mortality and significant morbidity (p=0.008).

Conclusions:
Although technically challenging, the surgical repair can be accomplished with acceptable early results. Heterotaxy syndrome, with concurrent anomalous connections of the pulmonary veins, represented the strongest identified risk factor for death or significant complication.