defect with common atrioventricular junction and malformations of the ventricular outflow tracts presents a significant challenge for the surgeon. In the most common of these, the association with tetralogy of Fallot, several surgical techniques have been described, and shown to deliver excellent results. 1-10 On the other hand, in the setting of more extreme malformations, such as double-outlet right ventricle, discordant ventriculo-arterial connections, or common arterial trunk, albeit rare lesions, the combination presents a more formidable surgical challenge, as evidenced by the few reports of successful repair of these lesions. This challenge is both physiological, when dealing with a very sick neonate or infant, as well as anatomical in terms of the complexity of the malformation and the ability to achieve a successful biventricular repair. Our goal in this review is to discuss the surgical treatment in the setting of tetralogy of Fallot and double outlet right ventricle, with emphasis on biventricular repair.
Incidence and classificationAlthough the incidence of common atrioventricular junction in the setting of tetralogy of Fallot can be estimated from published clinical series, the true incidence of more complex anomalies, such as double outlet right ventricle, is harder to gauge due to the paucity of published reports. The true incidence of these anomalies can be obtained from a landmark paper published by Bharati and associates, 11 which described the association of a common atrioventricular junction with tetralogy of Fallot, double outlet right ventricle, or discordant ventriculo-arterial connections. These anomalies were found in 81 out of 507 specimens with common atrioventricular canal, with 30 specimens having tetralogy of Fallot, 34 double outlet right ventricle, and 17 discordant ventriculo-arterial connections. Bharati et al. 11 further found that, amongst the cases with tetralogy of Fallot, almost all of the specimens had a common atrioventricular valvar orifice, which they nominated as "complete" defects, the remainder having a common atrioventricular junction, but with separate valvar orifices for the two ventricles, albeit, with the potential for interventricular shunting. They called these "intermediate" defects, although the junction is just as common, and the valve has the same basic morphology, apart from the separateness of the valvar orifices for the right and left ventricles. Similar proportions of morphologies were observed among the cases with double outlet right ventricle and transposition. It is well recognized that, in these settings, there can be any arrangement of the atrial appendages, common atrioventricular junction being frequently found in the setting of heterotaxy syndromes.The classification of the specific morphology of the common atrioventricular junction in the setting of tetralogy of Fallot or transposition is straightforward. On the other hand, the classification with double outlet from the right ventricle can be more complex and